Nova (1974–…): Season 44, Episode 10 - Search for the Super Battery - full transcript
We live in an age when technological innovation seems to be limitlessly soaring. But for all the satisfying speed with which our gadgets have improved, many of them share a frustrating weakness: the batteries. Even though there ha...
REPORTER:
Developiping news...
DAVID POGUE:
They're in the news,
in your pocket...
Take a look at the hole
in this guy's shorts...
POGUE:
And on your mind.
What's going wrong
with our batteries?
REPORTER:
Turn this phone off.
(glass shatters)
POGUE:
For the last few decades,
Batteries have powered
a revolution
in personal electronics,
changing our lives.
And now they're headed
for our cars.
Are electric cars
becoming a thing?
Yes, they are.
POGUE:
Even the grid...
DANIEL KAMMEN:
Renewable energy means
that we need energy storage.
POGUE:
But are we already
pushing their limits?
THEO GRAY:
Anything which is able to
release a lot of energy,
that is a potentially
dangerous thing.
(explosion)
POGUE:
Or can they be better?
I'm not seeing any fireball.
ZIMMERMAN:
We've got to work with people
that want to introduce
the true next-generation
battery.
Y. SHIRLEY MENG:
There is definitely a race
who will invent the next
big battery technology.
The deck's stacked
against all of us,
but the rewards are so big.
POGUE:
Can we beat the odds
as we "Search for
the Super Battery"?
Right now on NOVA.
(clanging)
POGUE:
The lowly battery.
We barely notice you
when you work.
And we curse you when you don't.
You're the "no show,"
the "missing ingredient,"
"not included."
(engine sputters)
And when you die...
a piece of us dies as well.
(loud crash, shouting)
Face it, battery,
you have issues.
But cheer up, my humble friend.
Things may be changing.
Scientists all over the world
are in a race
to make you better,
to make you powerful,
to make you cleaner,
to make you cheaper.
To make you into
a super battery.
It won't be easy,
but the stakes are huge...
(thunder rumbles)
Warmer temperatures, more severe
storms, higher sea levels.
What's causing all this
climate change?
Scientists virtually all agree:
burning fossil fuels--
the oil, gas, and coal
that have powered
our civilization up to now.
The challenge is
to make the switch
to other forms of energy,
like renewables--
solar and wind--
and to trade our
gasoline-burning vehicles
for greener electric ones.
But all of these are missing
the same critical component:
the right energy storage,
a battery.
Can science transform this
Clark Kent of energy
into the super storage
of tomorrow?
I'm David Pogue, and if that
perfect future battery exists,
I'm going to find it.
Because you never know
when you might need one.
(splash)
POGUE:
All right,
castaway, deserted,
nothing to survive with
but my wits.
Let's take inventory:
Luckily I have a knife.
Hmm, a phone charging cable...
and... yes!
A phone!
This is going to be easy.
Hello, 9-1-1.
(laughs)
Oh, no.
No, no, no, no!
It's dead!
To make this phone work,
I need a portable source of
electrical power.
I need a battery.
Hmm, what do I remember
about batteries?
A battery always has
a positive electrode,
a negative electrode,
with something called an
electrolyte in between.
When there's an
external connection
between the two sides,
the battery starts working.
First, the negative side reacts
with the electrolyte,
and electrons are set free.
As they travel
through the circuit,
they do useful things
like produce light.
When they reach
the positive side,
the electrons are reabsorbed.
Chemical reactions,
where one material gives up
electrons to another,
are common.
That's what happens
when a fire burns.
Or rust forms.
Or even when you breathe.
So building a battery
isn't that hard.
All you need
are the right materials,
like the kind of stuff you might
find on a beach.
The ingredients for a battery:
a negative electrode--
an aluminum can.
A positive electrode--
in this case I've got some
charcoal in my pants.
And finally, an electrolyte.
I have some fresh,
organic seawater.
The good news is this aluminum
can battery actually works.
And if I had a device
that could measure the voltage,
I could show you.
The bad news is
I need 50 of them.
♪ ♪
All right, 50 cans, one battery,
one dead phone.
This is the moment of truth.
It's charging!
Can I make a call on this thing?
9-1-1.
Hello?
Oh, I'm so happy
to hear your voice.
Listen, I was on this cruise
ship and I fell overboard.
I think somebody pushed me.
And now I'm on this desert
island, I don't know where I am.
Can you...
Landmark?
Look for a landmark?
Oh.
Actually, never mind.
In truth, charging a smartphone
from an aluminum-can battery
is really difficult.
My cheap low-power phone barely
let me make one call.
But the point is making
a bad battery is easy.
Making a good battery?
Well, that's hard.
And I've asked the experts.
I don't know if I would call it
a super battery,
but to get to the next
generation of battery,
it'd have to be
higher energy density.
Energy density, which is
how much energy you store
in a given volume.
What that means to the consumer
is that you might be able
to run that device
for a longer period of time.
Optimistically speaking,
we should be able to double
or triple the energy density
in the next ten years.
Cost is another factor
that is hugely important.
Cost is very important.
And at the same time be safe.
Safety.
Safety and cost,
as you can see,
can play against each other
where you can make
a very cheap battery
that can be very unsafe.
So those are just
some of the ones
that we look at all the time.
And they're not easy
things to deliver.
POGUE:
So that's a lot to ask
of one battery.
But finding that
battery for electric vehicles
may be critical to fighting
climate change.
Burning fossil fuels,
like gasoline,
emits carbon dioxide, a
greenhouse gas that traps heat,
causing warmer temperatures
and climate instability.
(thunderclap)
Transportation accounts
for about a quarter
of all U.S. greenhouse gas
emissions.
Cars and oil are linked
very, very strongly.
Something like 67% of oil goes
for gasoline
and 90-some percent of
transportation fuel is gasoline.
The whole purpose of electric
vehicles is to reduce
the amount of carbon footprint,
to reduce the amount
of emissions.
POGUE:
Electric vehicles could be good
for the environment.
But it's going to take a lot
to pry the gasoline nozzle
from our hands.
The funny thing is,
this isn't the first time
that electric batteries
and gasoline have fought
to win our automotive hearts.
(car horn honking)
At the turn of the century,
no one knew which technology,
electric or gas power,
would dominate the nascent
car industry.
In fact, quiet electric-powered
cars were a common sight
on the streets of New York.
To learn more, I pay a visit
to one of the foremost experts.
Or at least one of the funniest:
Jay Leno.
And he's got some insider info
on the car of tomorrow.
I think this is the car
of the future.
This is how we'll all be
getting around: electric.
This is the car
of the future?
LENO:
Well, this is
a 1909 Baker electric.
There's no pollution.
This was high-tech back
in the day.
POGUE:
Talk about back to the future.
The 1909 Baker runs on energy
stored in batteries.
Wow.
You have six
batteries in front.
POGUE:
As with today's electric cars,
you could charge the batteries
by plugging the car in.
I'm going to stop
at exactly ten bucks.
POGUE:
In those days,
there were charging stations
all over New York City.
Do you want to go for a ride
and see what it's like?
Yeah!
This runs?
You don't take it on...
Of course it runs.
You seem so stunned by...
(laughs)
I like this.
You've got the user's
manual on the seat.
That's a good sign.
But I'll show you how sort of
maintenance-free these are.
All you do is turn the key...
(bell rings)
And you are, uh...
That's the wheel?
...ready to go.
(bell rings)
Oh, my God.
No way!
Oh, my God.
POGUE:
Even today it's a great ride--
really quiet, just the hum
of an electric motor.
But back then,
electric cars still lost out.
Their batteries weren't
dependable
and many were recalled.
By the time the problems had
been sorted out,
a former Detroit Edison
employee, Henry Ford,
had unleashed the extremely
affordable
gasoline-powered Model T.
A few years later,
one of its big drawbacks,
the hand-crank starter, was
replaced with an electric one.
That, and the growing
availability of cheap gasoline
in rural areas that lacked
electricity
eventually sealed the deal.
Today, thanks to climate change,
electric cars are getting
another shot.
Success probably depends,
once again, on the battery.
The best version
we've managed so far
is probably the one
in your pocket--
the battery in your phone,
which uses the element lithium.
MAN:
The hoverboard is on fire.
POGUE:
And you also may have heard,
they can be dangerous.
WOMAN:
Stay away!
MAN:
I am, Mom!
(explosion)
REPORTER:
This happened at a gas station
in Kentucky
when his e-cigarette
battery exploded,
literally lighting his pants
on fire.
REPORTER:
This morning,
technology giant Samsung
planning a massive recall.
POGUE:
Then, of course,
there's the Samsung recall
of over two-and-a-half million
cell phones
because of lithium
battery fires.
So if it can be so dangerous,
why lithium?
What makes that element both
the belle of the battery ball
and at times a fiery mess?
(explosion)
To learn more about lithium,
I visit my friend with all
the "elementary" answers,
mad scientist Theo Gray,
at his mad-scientist workshop
on his Illinois farm.
♪ ♪
Nice!
POGUE:
In the past,
Theo has shown me the power...
(pops)
Whoa!
...of the elements.
Oh, the humanity!
(explosion)
So what's the story on lithium?
It seems like once you start
digging into the battery world,
you hear about lithium a lot.
So, what is lithium?
Yeah, so lithium is an element
that, you know,
happens to have
properties that make it
extraordinarily well suited
for delivering a lot of
electrical power
in a very small, light package.
And I'm guessing because
we're in Storm Trooper outfits,
that it's something dangerous.
It is able to contain and
release a lot of energy,
and any time you have anything
which is able to release energy,
that is a potentially
dangerous thing.
POGUE:
Theo tells me you can learn
a lot about lithium
just by looking at its place
on the periodic table.
High up means it has
a low atomic weight.
That means lithium
doesn't weigh much.
Which is, you know, a great
thing if you're trying to make
a battery to fly a drone or,
you know, just to have something
that gives you a lot of power
and doesn't weigh very much.
POGUE:
In fact, even though it's a
metal, it floats on water.
Oh, it's silver.
Pretty.
Thank you.
You notice again,
it weighs nothing.
Wow.
POGUE:
Theo also points out
that lithium sits on the far
left of the table
in the column called
the alkali metals.
Compared to other elements, they
readily give up an electron--
exactly what you want for the
negative electrode in a battery.
The lithium in my hand
is doing just that,
giving up an electron
to oxygen in the air,
creating the blackish lithium
oxide on its surface.
Theo, would we call
this oxidizing?
It is oxidizing.
It is basically ruing.
It is the exact same
reaction as rust forming.
It's just that, you know,
iron rust is kind of
a reddish flaky thing.
Lithium rust is
this kind of black coating.
POGUE:
When Theo whips out
some lithium foil,
I get an even better look
at the oxidizing process
thanks to the foil's greater
surface area.
You see how it's darkening?
It's tarnish...
it's like tarnish.
And that's more or less
the same reaction
that would happen
inside the battery,
except inside the battery
it's happening
in a very controlled way.
Wow, now it's not shiny
and pretty anymore.
I bet it's getting
hotter too.
It's super hot.
POGUE:
The lithium foil
reacts quickly in the air.
But if you really want to see it
in action, try water.
(sizzling)
(Pogue guffaws)
(explosion, glass shattering)
(Pogue laughs)
(coughing)
That was a great one.
POGUE:
Lightweight, and willing to give
up electrons easily,
lithium is nearly a perfect
metal for use
as the negative electrode
in a battery.
Nice.
POGUE:
But it turns out
there's a big problem if you
want that lithium metal battery
to be rechargeable.
Remember the three parts
to a battery?
Okay, I left some things out.
In a lithium-metal battery
and many others,
there's a separator,
like a piece of plastic,
to keep the electrodes apart,
because if they touch...
more on that later.
That separator
isn't completely solid,
and here's why.
When a lithium-metal battery
discharges,
of course there's a flow of
negatively charged electrons
through the wires
on the outside.
But inside the battery
there's also a flow
of positively charged
lithium atoms, or ions,
in the electrolyte.
They fw from the negative
lithium-metal electrode
through the permeable separator,
to the positive electrode,
which, kind of like
an apartment building,
houses the ions in its layers.
Recharging the battery sends
both the electrons and the ions
back the other way.
And that is when using lithium
metal as an electrode
runs into trouble.
Scientists discovered
that over time,
the returning lithium ions
tend to clump
on the metal surface,
building spiky, treelike
structures called dendrites.
CRABTREE:
They get rougher, rougher,
and rougher
until they stick out
like a finger
from the surface and continue
to get longer
and longer and longer.
JEFF SAKAMOTO:
And eventually those dendrites
can reach the other side
of the battery,
which is the cathode,
or the positively
charged electrode.
And then there's-- (snaps)--
a short circuit,
instantaneous discharge.
POGUE:
Instantly,
electrons flood across,
releasing the battery's energy,
generating heat, which in turn
can cause fire and explosions.
After years of trying,
no one could find a solution
to the lithium-metal conundrum.
So scientists invented
an alternative
that became part of our lives
in the early '90s,
in products like
the Sony Handycam.
They called it
the lithium-ion battery.
The key to its success
was replacing
the negative lithium-metal
electrode
with a newapartment
building"--
a carbon electrode that housed
lots of individual lithium ions
when the battery was charged.
Everything else
still worked the same.
Discharging the battery sent
the ions through the electrolyte
over to the positive electrode.
Recharging the battery
sent them back.
But now, at least in theory,
all the welcoming spaces
in the layers of the negative
electrode stopped them
from piling up
into dangerous dendrites.
That meant lithium-ion batteries
were far safer
than lithium-metal ones.
But at a price.
They stored far less energy.
REPORTER:
The FAA has long warned airlines
of the potential dangers
presented by lithium batteries.
POGUE:
And safer doesn't mean
completely safe.
REPORTER:
Lithium-ion batteries
have already been linked
to numerous cargo crashes.
POGUE:
All those battery fires
you've been hearing about
in recent years?
Those are lithium-ion batteries.
To learn more about what really
goes into a lithium-ion battery,
I traveled to Ann Arbor
to check out the University
of Michigan's battery lab,
part of its Energy Institute.
Senior lab manager Greg Less has
offered to show me around,
and even build one with me.
Turns out lithium-ion batteries
come in different shapes.
Okay, so this we've seen before,
this is like a watch battery.
Right.
This is a little bigger
than the standard double A.
LESS:
Absolutely, that's a 18650.
And you might find that
in a rechargeable
power tool,
an older model laptop,
or the Tesla Roadster.
But I've never seen this
in a power tool.
Well, no, there's actually
a bunch of them in there,
maybe six or seven, put together
in series inside of that brick
that you plug into
the bottom of the tool.
Oh, okay.
And this--
what, for a phone?
Yup, you'd find a battery
like that either in your phone
or a laptop or
a tablet computer device.
And you actually made
all these in this room?
Yes, we sure did.
That's cool.
Walk me through it,
good sir.
I happily will.
POGUE:
Greg gives me a whirlwind tour
of the process
of making an 18650.
He mixes up the ingredients
for the electrode material,
which gets baked onto foil
and sliced into smaller rolls.
Then we enter through an airlock
into a special low-humidity
dry room.
Any moisture from water inside
a lithium-ion battery
harms the electrolyte.
Once inside...
Here we go!
...we put the rolls on this
crazy machine,
which winds them together
with a roll of plastic separator
into a "jelly roll."
Let's take a closer look.
So we have a top layer
that's the separator.
Yeah.
We'll pull that off.
Then we have our copper and
graphite negative electrode.
Another layer of separator here,
and then the positive
electrode layer
that we made together
of lithium-nickel-manganese-
cobalt oxide.
So every lithium-ion
battery
that's in one of
those cylinders,
including the ones
that are bundled together
to make laptop batteries
and power drill batteries,
they're all at heart
a bunch of these ribbons?
That's correct.
Wow.
POGUE:
After sticking the roll
into a metal can,
Greg injects the last
key ingredient,
the liquid electrolyte.
LESS:
The electrolyte is
the cream
in the jellyroll.
It's what connects
everything together.
The electrolyte is a liquid
solution that has lithium ions
dissolved in it,
and when we charge or discharge
the battery,
the electrolyte is what allows
those ions to travel back
and forth
between the positive
and negative electrodes.
(beeping)
POGUE:
With the final steps of welding,
and crimping the top onto
the metal can, we were done.
Somehow I expected more.
Because it's batteries
like the 18650
or one of the other lithium-ion
styles like these flat ones
in pouches, that will determine
if electric cars
are a viable option
to replace gas-burning ones.
So far in the U.S.,
plug-in electric cars
haven't had much success.
In 2015, they made up
less than one percent
of all new car sales.
VENKAT SRINIVASAN:
There are a few reasons
to be skeptical
of electric cars.
Probably the biggest one
is cost.
But costs of electric car
batteries
are coming down dramatically,
and they'll continue to come
down for the next five years.
They're going to find out that
more and more people can afford
to buy an electric car.
So that problem is getting
solved as we speak.
(bell rings)
POGUE:
The other concern
is called range anxiety--
how far can you go
on a single charge?
Surveys show Americans want to
be able to go hundreds of miles,
even though the average daily
auto use is only around 40.
But there is some justification.
For most of the country,
roadside charging stations
are few and far between.
Despite lackluster sales,
car makers continue to test
the waters,
with lower prices
and longer ranges.
Like the Chevy Bolt,
the first moderately priced
all-electric car
with a range
of more than 200 miles.
Or the new Tesla Model 3, which
has a similar price and range.
Anticipating a large demand,
Tesla plans to produce
500,000 cars a year
in the latter half
of the decade.
But that would require
the entire current
worldwide production
of lithium-ion batteries.
So they've built this:
the Gigafactory in Nevada.
When it's completed,
it will cover more land
than any building in the world,
and it will produce batteries,
"faster than bullets
from a machine gun."
So this is the...
I stop in at Tesla's Palo Alto
headquarters
to find out where all those
batteries fit
in the current Tesla Model S.
So the battery pack
actually runs the length
and the width of the vehicle,
so what you're seeing right
under here is our battery pack.
Oh, the batteries
are already in here?
The batteries are in here.
Now if I could go in there with
a screwdriver and rip that open,
what would the actual
batteries look like?
Are they just a whole bunch
of little double As?
They're little cells, yes.
So we've got about 8,000
individual cells in there.
8,000?
Yes.
And do, by any chance,
do they look like this?
POGUE:
In fact they do.
Early on, Tesla standardized
on the 18650
because of its availability.
But at the Gigafactory, they'll
switch to a bigger version,
which they claim is the best
and cheapest in the world.
Other electric car makers prefer
the flatter pouch batteries,
like those made here for GM
at LG Chem's plant
in Holland, Michigan.
While I was there, I stopped in
to see Denise Gray.
She's the president and CEO
of an LG Chem subsidiary
that does battery research
and design.
So we've heard for years that
electric cars are coming soon.
But are they finally,
at least almost, here?
POGUE:
This plant makes exclusively
batteries for
electric cars, right?
Like are electric cars
becoming a thing?
Yes, they are. Yes, they are.
We're still in the early
stages, but we're making
great progress and I think we
are accelerating down that plan
of having more and more
electrified powertrains
on the road.
POGUE:
How many Americans will buy
electric cars, or how soon,
remains to be seen,
but with more and more
electric vehicles on the road,
engineers are racing to make
the lithium-ion batteries
they contain even better--
cheaper to produce, longer
lasting, and, most importantly,
safer.
I travel to New Mexico
to visit the Sandia National
Laboratories.
Scientists Leigh Anna Steele
and Josh Lamb
show me the battery abuse
testing lab.
Here they do all the things
those warning labels tell you
not to do with batteries
to understand how they fail.
They take me past
a two-ton blast door
to the testing
torture chambers,
where they puncture, overcharge,
burn, short-circuit,
and drown batteries.
The walls, ceilings,
and floors of this building
are all made out of concrete,
reinforced with rebar,
anywhere from 12
to 14 inches thick.
POGUE:
Today they're performing
a crush test,
where they'll slowly smash
the middle of a battery
with up to 15,000 pounds
of force,
the sort of thing that could
happen in an electric car crash.
This is
a hydraulic lift here.
So, it's going to actually
start lifting up
and that impactor there is going
to start crushing the battery.
POGUE:
After a final check of the
setup, we are ready to go.
Okay, Chris, are we ready
to start the test?
All right.
Test is going now, it sounds
like, so we can hear...
we heard hydraulics just
turned on a little bit.
POGUE:
On the hydraulic lift,
the battery slowly rises
into the plunger.
You can start seeing
the gap is starting to close
in between the plunger
and the battery.
POGUE:
You can see the plunger is
crushing the inner battery cells
a surprising amount,
still with no reaction.
But we're getting close.
So you'll start hearing
some hissing.
That's the battery venting
when it actually starts
to go into failure.
(hissing)
(Pogue guffaws)
POGUE:
That's why we weren't
standing in that room.
STEELE:
Exactly.
LAMB:
So all that energy that's
stored in that battery,
it's just discharging
all at once.
POGUE:
When a lithium-ion battery cell
uncontrollably overheats,
it's called "thermal runaway."
Leigh Anna and Josh
break it down for me.
The plunger crushed the
inner cells of the battery
until a negative and positive
electrode made contact--
a short circuit.
Just like when dendrites
short out a battery,
electrons flooded across
in a massive discharge,
creating heat, which then turned
some of the liquid electrolyte
into gas.
That burst open the battery's
foil pouch,
and then the vaporized
electrolyte ignited.
That's known
as venting with flame.
All the fire and heat set off
reactions in other nearby cells,
sending them
into thermal runaway as well.
In the end, the fire
reached a temperature
of over 1,800 degrees
Fahrenheit,
easily hot enough to melt the
aluminum used in the battery.
Leigh Anna and Josh show me
some video of other tests.
This is a battery
that's getting overcharged.
And this is a nail going into
the center of a group of 18650s.
The center cell fails,
gradually taking down
the rest of them with it.
(popping, sizzling)
From the videos,
and having seen it here myself,
one thing seems obvious:
if there were a way to get rid
of the vaporizing flammable
electrolyte,
that would be a big step
toward making these
batteries safer.
And I'm not the only one
who thinks so.
Meet Mike Zimmerman.
He's a Tufts University
professor
and materials scientist.
About five years ago
he got interested
in lithium-ion batteries,
thinking there had to be
a safer electrolyte.
Mike's background is in plastics
and I've come to take a look
at what he's invented.
So this is your battery.
That's the battery.
It looks like any other lithium
battery inside one of these.
It's the same.
Okay.
Same format.
Same voltage?
Same voltage.
You think this is
an unusual battery?
It's a battery
that is much safer
than conventional batteries.
And upon any damage,
any puncture, any cutting it,
it will not catch on fire.
Did you say,
"Any cutting it?"
Correct.
(laughs)
Can I make a cut in this?
Yes.
Really?
Yes.
It's not going to
jet fire into my face?
It will not.
POGUE:
Before I do that, let's consider
these examples from YouTube
of folks poking
at lithium-ion batteries.
They reveal that
it doesn't take much
to create a dangerous
short circuit...
(explosion)
...with disastrous results.
(hissing)
And now, is it my turn?
Big or little?
Whatever you want.
I'm alive!
Wow.
Look at that!
And guess what,
the lights are still on.
This is like a Houdini thing.
I mean, this is like
I'm going to make a doily.
Oh, my God, it's still on!
Come on!
I'm going to make
you a little paper doll.
POGUE:
So what's the trick?
Compared to a typical
lithium-ion battery,
Mike's replaced the liquid
electrolyte and the separator
with his special plastic
to create a completely
solid battery.
Unlike the liquid electrolyte,
which easily catches fire,
Mike's plastic
is flame-retardant.
And even though it's solid,
amazingly, it allows lithium
ions to pass through it
at a rate equal to
or better than
the current liquid electrolytes.
And here's the best part:
the plastic physically
prevents dendrites
from shorting out the battery.
That means that Mike can go back
to a lithium metal
negative electrode,
potentially doubling his
battery's energy density.
Here's another demo
using an iPad
with its original battery
removed and in its place
one of Mike's that's even bigger
than the last one cut to pieces.
And I'm going to stick
a screwdriver through it
like you saw
in those YouTube videos.
Here we go.
So far I'm not seein.
Okay, you've done it,
you've made a battery that
doesn't explode when pierced.
Uh, at the very least I would
expect to see some smoke.
I would expect
to feel some heat.
There's nothing.
Yeah.
It's because of the solid
plastic electrolyte.
It's not flammable.
And it's very insulative.
It doesn't get too hot
and it doesn't burn.
And it keeps working!
Well, that was
an unintended consequence.
Can I do it again?
My mortgage is too high!
And the tax rates
are insane!
And I dented my fender!
All right, now it's not
going to turn on now.
Oh, come on!
Come on!
Oh!
That's it.
A damaged battery.
And yet no smoke,
no flame, no sparks.
Do not try this
with your iPad battery.
POGUE:
So far, Mike's kept
his company's work
mostly under wraps.
This, in fact, is the first
television interview
he's given on it.
But there's still more
development to go
before your new smartphone
makes use of it.
And if I were one
of your critics,
certainly there
would be something
I would attack you for.
There's got to
be something.
It can't be too good
to be true.
Right.
I think that development,
you know, is never done.
We have to do a lot
of reliability testing,
and the scaling up
aspect of this,
it's going to be a lot
of work to scale it up.
So we've got to work with people
that want to do that
and want to introduce a true
next-generation battery.
will come to market
anytime soon is hard to know.
If it does, and if it can double
the energy density
of the batteries
in electric cars,
that would be revolutionary.
But electrifying cars
as a strategy
to battle climate change
comes with a big caveat.
To have real impact,
the source of their electricity
needs to be green as well.
And that means cleaning up
the grid that charges them.
If you're like me, you don't
even think about it.
You flip on a light switch
or you turn on something plugged
into the wall,
where does the electricity
come from?
When was it created?
How does it arrive at your house
at exactly the right time?
How does the electrical grid
work?
KAMMEN:
The grid has been called
the most complex machine
humans have ever built.
It is the largest,
the most extensive,
has the most parts,
and it also has
a beautiful simplicity.
It's driven by this very simple
"energy in must equal energy out
at every moment in time."
You have to generate electricity
over here at the power station
at exactly and instantaneously
the same rate
that you use it over here
on all the customers.
Electricity is essentially
instantaneous.
So, it's a fraction of a
millisecond or microsecond old
because it travels basically
at a fraction
of the speed of light
across the wire.
So we have to make it
instantaneously.
The moment you want it,
I have to make it.
(electric buzzing)
POGUE:
Matching the demand means
constantly ramping up and down
the amount of electricity
generated--
for example, by turning up or
down gas-fed power plants
or spilling more water
over dams,
or even firing up
an old diesel plant
just to meet an hour
of peak demand.
It's a constant,
complicated dance.
Now as we try to shift away
from power plants
running fossil fuels,
the complicated dance that
matches generation with demand
has found some new partners--
renewables, like wind and solar.
They can range in size
from a huge wind farm
generating hundreds
of megawatts of power,
to the small solar array
on your neighbor's house.
The dance just got
more complicated.
CONZELMANN:
We're taking a complicated
system
and making it a lot more
complicated.
We have to be able to meet
the demand still
when the sun doesn't shine,
when the clouds come through
and the output falls,
when the wind dies down.
POGUE:
If these new renewable
but intermittent
sources of electricity
are going to play a major role
on the grid, they require
a new player: energy storage.
I don't think renewable
penetration can go higher
without a robust energy storage
solution, that's for sure.
POGUE:
In the U.S., there's already
a little energy storage
on the grid,
equal to about two percent
of our generating capacity.
Most of it looks
like this reservoir
in Bath County, Virginia.
It's been called the largest
battery in the world.
But it's not like
any battery you've seen.
The system is called
"pumped hydro"
and it operates like a
rechargeable hydro-electric dam.
During the day, when there's
high demand for power,
the electric company lets
the water flow
from an upper reservoir
to a lower one,
spinning turbines
and generating electricity.
But at night,
when there's low demand,
they use the excess electricity
generated by other plants
to pump water back up
to the higher reservoir,
recharging it.
Today, about 99% of all grid
storage in the United States
is pumped hydro.
It would be a relatively
inexpensive way
to store excess energy from
renewables for later use,
except for one problem.
You need the right geography
for the site
with changes in elevation.
And even then,
creating new ones can raise
environmental concerns.
So the search for solutions for
grid energy storage is still on.
Just outside San Francisco
in the Bay Area,
one company is giving it their
own spin-- Amber Kinetics.
They sell an energy-storage
system built around
massive spinning disks
called flywheels.
The principle is simple:
Electricity powers a motor that
spins up the heavy flywheel.
Now, energy is stored
in the flywheel's momentum.
To convert that back
into electricity,
the flywheel engages
a generator,
its momentum turning
the generator's shaft.
As the flywheel slows, the
generator creates electricity.
Needing both weight
and strength,
Amber Kinetics makes their
flywheel out of steel.
How much do these babies weigh?
This is about
a 5,000-pound rt.
Wow, and how fast is it
going to be spinning?
It's some good number
of thousands of RPM.
POGUE:
In a finished unit,
the flywheel sits inside
a welded steel chamber
that tightly seals shut,
so it can spin in a near vacuum
to reduce friction with the air.
They also reduce friction
using a giant magnet
mounted above the flywheel,
which lifts it upward,
removing most of its weight,
so it rests only lightly
on its support bearings.
SANDERS:
And so the friction
in the mechanical bearing
is partly determined
by how much force
is the bearing supporting.
And so we make the force
extremely light.
POGUE:
All of this adds up
to breaking new ground.
Flywheels have been used
on the grid before,
but mostly to store energy
only for seconds or minutes.
Amber Kinetics' flywheels can
store energy
for up to four hours--
for example, capturing
the energy generated
by a solar array durin
the day for use in the evening,
a process called time shifting.
Seth shows me
what a nearly complete
flywheel unit looks like.
There's a flywheel in here
that you made.
But is it spinning right now?
No, it's at rest now.
Okay, if it were spinning,
would I hear it?
You would not be
able to hear it,
because the part is balanced
to a very high degree,
and the residual vibration
is minuscule.
POGUE:
As a grid storage solution,
flywheels, a kind of
electro-mechanical battery,
have an advantage
over chemical batteries.
They don't wear out for decades.
The same can't be said
for lithium-ion batteries,
but there are a lot of those
getting put to work
on the grid as well.
This is Tehachapi, California,
near the Mojave Desert,
home to some of the oldest
and largest wind farms
in the country.
But the wind blows
strongest at night,
when demand for electricity
is at its lowest.
In 2014, Southern California
Edison installed
a $50 million energy
storage system
that uses lithium-ion batteries.
What we want to do is be able
to use this to smooth out,
firm up the output of those so
it's much more predictable.
For example, when the wind blows
during the nighttime,
capture that energy and then
use it during the daytime
when the demand is high.
POGUE:
Lithium-ion batteries have made
inroads into grid storage,
but they're still expensive.
And part of the premium paid
is for their light weight,
which matters for electric cars
and portable electronics,
but maybe not for the grid.
Here in the Pittsburgh area,
battery scientist Jay Whitacre
has taken a different approach.
He's sacrificed lithium ion's
lightweight portability
to create a battery that is
cheaper and safer.
It's nicknamed
the saltwater battery.
We're going to retrace his
steps, starting at square one:
the periodic table.
Ra-Ba-La.
Er...
All right, so these are the
elements that make up our world.
Mm-hmm.
POGUE:
Which elements can you use to
make a battery?
WHITACRE:
Really, almost any of them.
If they have any reaction
potential at all,
you can make electrodes out of
them and they'll store energy.
That's not that hard.
But that's not really the
question you want to ask, right?
You want to ask
which of these elements
can we use
to really scale large,
like really big energy storage
to solve the world's
problems, right?
And to answer that question, we
really get rid of most of this.
Like this...
this is is gone.
We slide this out.
And then we start thinking about
what's called crustal abundance.
Crustal abundance?
Crustal abundance.
POGUE:
Crustal abundance is an estimate
of the availability
of an element in the earth's
outer layer, itsrust.
The higher the percentage,
the more available it is,
which translates into cheaper
and probably better
for the environment
since it's more common.
So if you can pick from crustily
abundant materials or elements,
you're probably going
to have the best shot
at having a low-cost,
environmentally safe battery.
I'm always in favor
of crustily abundant.
WHITACRE:
So, silicon.
These will not surprise you.
You have carbon, you have
hydrogen, you have zinc.
These are in no
particular order,
but you'll recognize
all of them.
They're very
common materials.
They make up everyday life.
Oxygen and a couple
of really important ones.
You've got sodium,
which is, obviously,
everywhere in the ocean.
You've got potassium, which
is a heavy biological factor,
and lithium, which you might not
think is crustily abundant
but actually is.
And these were the ones that
I started looking at in 2007
when I was trying to figure out
what elements I would use
to put together in any which way
to create something
that was going to be functional.
POGUE:
Out of this initial collection
of elements,
Jay created a battery
that had a sodium manganese
oxide positive electrode
and a carbon negative electrode.
When the battery was charged,
sodium ions left the positive
electrode to gather
at the negative
carbon electrode.
When discharged,
they would return
to the positive electrode.
With each charge and discharge,
they shuttled back and forth.
The electrolyte, sodium sulfate
salt dissolved in water,
gave the battery its nickname--
the saltwater battery.
From there, Jay began
tweaking his recipe.
The end result was a battery
far less energy dense
than lithium ion
but non-flammable,
non-toxic and cheaper.
WHITACRE:
So this is a barrel
of our active material.
This happens to be
our cathode material.
It's a manganese oxide base
system, and it's really simple.
It basically looks
like dark sand or dark dirt.
Listen, Jay, I've been to a few
battery factories in my time.
I'm sure you have.
And I've never been allowed
to walk up to a barrel
in a non-humidity-
controlled room.
No, well, the key difference
between this battery
and probably all
the others you've visited
is that we use water
as an electrolyte.
POGUE:
Water changes everything
in a battery.
On the downside,
it limits the voltage.
Too high and the water splits
into hydrogen and oxygen gas.
But it also means you don't need
the expensive low-humidity
dry rooms
required to make
lithium-ion batteries.
And, of course,
water is nonflammable.
Safer.
In fact, the salts that we use
as electrolyte salts
are flame inhibitors.
Is this toxic, this thing here?
This is not toxic at all.
I could eat this
cathode material?
It is biologically
consumable, yeah.
I wouldn't recommend it.
It's going to taste
a little salty to you,
a little weird but yeah.
There you go.
Mmm, pumpkin spice.
Yeah, it's totally fine.
It's not even salty.
No, it's just like sand.
Yeah.
It is basically sand.
It's actually a little
better than sand,
as a frequent sand eater.
POGUE:
These days, Aquion Energy
is churning out batteries
in a former Sony Trinitron
factory outside of Pittsburgh.
Here, Jay's emphasis on safe
ingredients saves a lot of money
in manufacturing.
The electrode material
I taste-tested is pressed
into cookie-like wafers,
which in turn get assembled
by these pick-and-place machines
from the food industry,
used in packaging.
All without the tight humidity
and dust controls
found in lithium-ion
battery factories.
Already, saltwater batteries
are part
of hundreds of solar
installations around the world,
ranging from utility projects
to individual homes.
But Jay sees himself
at the beginning
of a massive undertaking:
to bring energy storage
to the grid.
WHITACRE:
This is not a small-scale
project.
Like, to get storage to be
relevant in the world,
you have to make
huge amounts of it,
and this is just
a drop in the bucket.
We're just getting started.
POGUE:
On that, everyone agrees.
If we want energy storage
to integrate renewables
into the grid, we're woefully
short on quantity.
In 2010, Bill Gates noted that
all the batteries on earth
could store less
than ten minutes
of the world's electricity
production.
To fill the gap,
we'll need systems that can
scale up easily.
Levi Thompson
at the University of Michigan
introduces me to one--
a rechargeable battery unlike
any other: the flow battery.
He explains that a typical
battery is a closed system.
And this is all sealed.
Okay.
So, everything that you need
is in there.
It's like a cake.
You put everything in there,
you get everything you want.
Every battery kind
of looks like this.
POGUE:
Every battery but a flow
battery, says Thompson.
Instead of a closed system,
a flow battery has external
tanks containing two chemicals.
They're pumped past each other
through a chamber.
Because of a special thin
membrane, they can't mix,
but in close proximity they do
react, generating electricity.
The capacity of a flow battery
depends on the size
of the external tanks
that hold the chemicals.
Bigger tanks, bigger battery,
more energy.
THOMPSON:
Flow systems are,
for large-scale applications,
much more efficient,
much more cost-effective
than sealed systems.
It's a much better solution
to the problem.
Flow batteries will surely
play a role in the grid.
This is what they have always
been designed for
and ought of as
the grid battery.
POGUE:
Some flow batteries
are already in operation,
like this one at Fort Devens,
a U.S. Army installation
in Massachusetts.
The battery helps integrate
solar generation,
reduces peak demand,
and improves power quality.
And research continues,
like the work of these two
members of Levi's team.
It's early days,
but with more development,
flow batteries might just
turn out to be the answer
for grid storage.
This is something
that's shown to work
and people are actually
using it,
but that's not the mind blower
so much as where it could be
in 40 years.
THOMPSON:
Where it could go.
Absolutely.
KAMMEN:
Flow batteries are perhaps
the newest exciting entrant,
but I would expect
over the next decade, there's
going to be a whole series
of these new, exciting entrants
into the field.
POGUE:
So, in the end,
we still don't know if
the grid super battery
will be one technology,
or a mix of pumped hydro,
chemical batteries, flywheels,
flow batteries, and others.
But if we really want
to integrate renewables
into the grid
and trade our carbon-spewing
vehicles for greener ones,
and do it on the massive scale
required to fight
climate change,
one thing's for sure:
energy storage, and lots of it,
will be in our future.
And so will the ongoing
search for the super battery.
This NOVA program is
available on DVD.
NOVA is also available
for download on iTunes.
Developiping news...
DAVID POGUE:
They're in the news,
in your pocket...
Take a look at the hole
in this guy's shorts...
POGUE:
And on your mind.
What's going wrong
with our batteries?
REPORTER:
Turn this phone off.
(glass shatters)
POGUE:
For the last few decades,
Batteries have powered
a revolution
in personal electronics,
changing our lives.
And now they're headed
for our cars.
Are electric cars
becoming a thing?
Yes, they are.
POGUE:
Even the grid...
DANIEL KAMMEN:
Renewable energy means
that we need energy storage.
POGUE:
But are we already
pushing their limits?
THEO GRAY:
Anything which is able to
release a lot of energy,
that is a potentially
dangerous thing.
(explosion)
POGUE:
Or can they be better?
I'm not seeing any fireball.
ZIMMERMAN:
We've got to work with people
that want to introduce
the true next-generation
battery.
Y. SHIRLEY MENG:
There is definitely a race
who will invent the next
big battery technology.
The deck's stacked
against all of us,
but the rewards are so big.
POGUE:
Can we beat the odds
as we "Search for
the Super Battery"?
Right now on NOVA.
(clanging)
POGUE:
The lowly battery.
We barely notice you
when you work.
And we curse you when you don't.
You're the "no show,"
the "missing ingredient,"
"not included."
(engine sputters)
And when you die...
a piece of us dies as well.
(loud crash, shouting)
Face it, battery,
you have issues.
But cheer up, my humble friend.
Things may be changing.
Scientists all over the world
are in a race
to make you better,
to make you powerful,
to make you cleaner,
to make you cheaper.
To make you into
a super battery.
It won't be easy,
but the stakes are huge...
(thunder rumbles)
Warmer temperatures, more severe
storms, higher sea levels.
What's causing all this
climate change?
Scientists virtually all agree:
burning fossil fuels--
the oil, gas, and coal
that have powered
our civilization up to now.
The challenge is
to make the switch
to other forms of energy,
like renewables--
solar and wind--
and to trade our
gasoline-burning vehicles
for greener electric ones.
But all of these are missing
the same critical component:
the right energy storage,
a battery.
Can science transform this
Clark Kent of energy
into the super storage
of tomorrow?
I'm David Pogue, and if that
perfect future battery exists,
I'm going to find it.
Because you never know
when you might need one.
(splash)
POGUE:
All right,
castaway, deserted,
nothing to survive with
but my wits.
Let's take inventory:
Luckily I have a knife.
Hmm, a phone charging cable...
and... yes!
A phone!
This is going to be easy.
Hello, 9-1-1.
(laughs)
Oh, no.
No, no, no, no!
It's dead!
To make this phone work,
I need a portable source of
electrical power.
I need a battery.
Hmm, what do I remember
about batteries?
A battery always has
a positive electrode,
a negative electrode,
with something called an
electrolyte in between.
When there's an
external connection
between the two sides,
the battery starts working.
First, the negative side reacts
with the electrolyte,
and electrons are set free.
As they travel
through the circuit,
they do useful things
like produce light.
When they reach
the positive side,
the electrons are reabsorbed.
Chemical reactions,
where one material gives up
electrons to another,
are common.
That's what happens
when a fire burns.
Or rust forms.
Or even when you breathe.
So building a battery
isn't that hard.
All you need
are the right materials,
like the kind of stuff you might
find on a beach.
The ingredients for a battery:
a negative electrode--
an aluminum can.
A positive electrode--
in this case I've got some
charcoal in my pants.
And finally, an electrolyte.
I have some fresh,
organic seawater.
The good news is this aluminum
can battery actually works.
And if I had a device
that could measure the voltage,
I could show you.
The bad news is
I need 50 of them.
♪ ♪
All right, 50 cans, one battery,
one dead phone.
This is the moment of truth.
It's charging!
Can I make a call on this thing?
9-1-1.
Hello?
Oh, I'm so happy
to hear your voice.
Listen, I was on this cruise
ship and I fell overboard.
I think somebody pushed me.
And now I'm on this desert
island, I don't know where I am.
Can you...
Landmark?
Look for a landmark?
Oh.
Actually, never mind.
In truth, charging a smartphone
from an aluminum-can battery
is really difficult.
My cheap low-power phone barely
let me make one call.
But the point is making
a bad battery is easy.
Making a good battery?
Well, that's hard.
And I've asked the experts.
I don't know if I would call it
a super battery,
but to get to the next
generation of battery,
it'd have to be
higher energy density.
Energy density, which is
how much energy you store
in a given volume.
What that means to the consumer
is that you might be able
to run that device
for a longer period of time.
Optimistically speaking,
we should be able to double
or triple the energy density
in the next ten years.
Cost is another factor
that is hugely important.
Cost is very important.
And at the same time be safe.
Safety.
Safety and cost,
as you can see,
can play against each other
where you can make
a very cheap battery
that can be very unsafe.
So those are just
some of the ones
that we look at all the time.
And they're not easy
things to deliver.
POGUE:
So that's a lot to ask
of one battery.
But finding that
battery for electric vehicles
may be critical to fighting
climate change.
Burning fossil fuels,
like gasoline,
emits carbon dioxide, a
greenhouse gas that traps heat,
causing warmer temperatures
and climate instability.
(thunderclap)
Transportation accounts
for about a quarter
of all U.S. greenhouse gas
emissions.
Cars and oil are linked
very, very strongly.
Something like 67% of oil goes
for gasoline
and 90-some percent of
transportation fuel is gasoline.
The whole purpose of electric
vehicles is to reduce
the amount of carbon footprint,
to reduce the amount
of emissions.
POGUE:
Electric vehicles could be good
for the environment.
But it's going to take a lot
to pry the gasoline nozzle
from our hands.
The funny thing is,
this isn't the first time
that electric batteries
and gasoline have fought
to win our automotive hearts.
(car horn honking)
At the turn of the century,
no one knew which technology,
electric or gas power,
would dominate the nascent
car industry.
In fact, quiet electric-powered
cars were a common sight
on the streets of New York.
To learn more, I pay a visit
to one of the foremost experts.
Or at least one of the funniest:
Jay Leno.
And he's got some insider info
on the car of tomorrow.
I think this is the car
of the future.
This is how we'll all be
getting around: electric.
This is the car
of the future?
LENO:
Well, this is
a 1909 Baker electric.
There's no pollution.
This was high-tech back
in the day.
POGUE:
Talk about back to the future.
The 1909 Baker runs on energy
stored in batteries.
Wow.
You have six
batteries in front.
POGUE:
As with today's electric cars,
you could charge the batteries
by plugging the car in.
I'm going to stop
at exactly ten bucks.
POGUE:
In those days,
there were charging stations
all over New York City.
Do you want to go for a ride
and see what it's like?
Yeah!
This runs?
You don't take it on...
Of course it runs.
You seem so stunned by...
(laughs)
I like this.
You've got the user's
manual on the seat.
That's a good sign.
But I'll show you how sort of
maintenance-free these are.
All you do is turn the key...
(bell rings)
And you are, uh...
That's the wheel?
...ready to go.
(bell rings)
Oh, my God.
No way!
Oh, my God.
POGUE:
Even today it's a great ride--
really quiet, just the hum
of an electric motor.
But back then,
electric cars still lost out.
Their batteries weren't
dependable
and many were recalled.
By the time the problems had
been sorted out,
a former Detroit Edison
employee, Henry Ford,
had unleashed the extremely
affordable
gasoline-powered Model T.
A few years later,
one of its big drawbacks,
the hand-crank starter, was
replaced with an electric one.
That, and the growing
availability of cheap gasoline
in rural areas that lacked
electricity
eventually sealed the deal.
Today, thanks to climate change,
electric cars are getting
another shot.
Success probably depends,
once again, on the battery.
The best version
we've managed so far
is probably the one
in your pocket--
the battery in your phone,
which uses the element lithium.
MAN:
The hoverboard is on fire.
POGUE:
And you also may have heard,
they can be dangerous.
WOMAN:
Stay away!
MAN:
I am, Mom!
(explosion)
REPORTER:
This happened at a gas station
in Kentucky
when his e-cigarette
battery exploded,
literally lighting his pants
on fire.
REPORTER:
This morning,
technology giant Samsung
planning a massive recall.
POGUE:
Then, of course,
there's the Samsung recall
of over two-and-a-half million
cell phones
because of lithium
battery fires.
So if it can be so dangerous,
why lithium?
What makes that element both
the belle of the battery ball
and at times a fiery mess?
(explosion)
To learn more about lithium,
I visit my friend with all
the "elementary" answers,
mad scientist Theo Gray,
at his mad-scientist workshop
on his Illinois farm.
♪ ♪
Nice!
POGUE:
In the past,
Theo has shown me the power...
(pops)
Whoa!
...of the elements.
Oh, the humanity!
(explosion)
So what's the story on lithium?
It seems like once you start
digging into the battery world,
you hear about lithium a lot.
So, what is lithium?
Yeah, so lithium is an element
that, you know,
happens to have
properties that make it
extraordinarily well suited
for delivering a lot of
electrical power
in a very small, light package.
And I'm guessing because
we're in Storm Trooper outfits,
that it's something dangerous.
It is able to contain and
release a lot of energy,
and any time you have anything
which is able to release energy,
that is a potentially
dangerous thing.
POGUE:
Theo tells me you can learn
a lot about lithium
just by looking at its place
on the periodic table.
High up means it has
a low atomic weight.
That means lithium
doesn't weigh much.
Which is, you know, a great
thing if you're trying to make
a battery to fly a drone or,
you know, just to have something
that gives you a lot of power
and doesn't weigh very much.
POGUE:
In fact, even though it's a
metal, it floats on water.
Oh, it's silver.
Pretty.
Thank you.
You notice again,
it weighs nothing.
Wow.
POGUE:
Theo also points out
that lithium sits on the far
left of the table
in the column called
the alkali metals.
Compared to other elements, they
readily give up an electron--
exactly what you want for the
negative electrode in a battery.
The lithium in my hand
is doing just that,
giving up an electron
to oxygen in the air,
creating the blackish lithium
oxide on its surface.
Theo, would we call
this oxidizing?
It is oxidizing.
It is basically ruing.
It is the exact same
reaction as rust forming.
It's just that, you know,
iron rust is kind of
a reddish flaky thing.
Lithium rust is
this kind of black coating.
POGUE:
When Theo whips out
some lithium foil,
I get an even better look
at the oxidizing process
thanks to the foil's greater
surface area.
You see how it's darkening?
It's tarnish...
it's like tarnish.
And that's more or less
the same reaction
that would happen
inside the battery,
except inside the battery
it's happening
in a very controlled way.
Wow, now it's not shiny
and pretty anymore.
I bet it's getting
hotter too.
It's super hot.
POGUE:
The lithium foil
reacts quickly in the air.
But if you really want to see it
in action, try water.
(sizzling)
(Pogue guffaws)
(explosion, glass shattering)
(Pogue laughs)
(coughing)
That was a great one.
POGUE:
Lightweight, and willing to give
up electrons easily,
lithium is nearly a perfect
metal for use
as the negative electrode
in a battery.
Nice.
POGUE:
But it turns out
there's a big problem if you
want that lithium metal battery
to be rechargeable.
Remember the three parts
to a battery?
Okay, I left some things out.
In a lithium-metal battery
and many others,
there's a separator,
like a piece of plastic,
to keep the electrodes apart,
because if they touch...
more on that later.
That separator
isn't completely solid,
and here's why.
When a lithium-metal battery
discharges,
of course there's a flow of
negatively charged electrons
through the wires
on the outside.
But inside the battery
there's also a flow
of positively charged
lithium atoms, or ions,
in the electrolyte.
They fw from the negative
lithium-metal electrode
through the permeable separator,
to the positive electrode,
which, kind of like
an apartment building,
houses the ions in its layers.
Recharging the battery sends
both the electrons and the ions
back the other way.
And that is when using lithium
metal as an electrode
runs into trouble.
Scientists discovered
that over time,
the returning lithium ions
tend to clump
on the metal surface,
building spiky, treelike
structures called dendrites.
CRABTREE:
They get rougher, rougher,
and rougher
until they stick out
like a finger
from the surface and continue
to get longer
and longer and longer.
JEFF SAKAMOTO:
And eventually those dendrites
can reach the other side
of the battery,
which is the cathode,
or the positively
charged electrode.
And then there's-- (snaps)--
a short circuit,
instantaneous discharge.
POGUE:
Instantly,
electrons flood across,
releasing the battery's energy,
generating heat, which in turn
can cause fire and explosions.
After years of trying,
no one could find a solution
to the lithium-metal conundrum.
So scientists invented
an alternative
that became part of our lives
in the early '90s,
in products like
the Sony Handycam.
They called it
the lithium-ion battery.
The key to its success
was replacing
the negative lithium-metal
electrode
with a newapartment
building"--
a carbon electrode that housed
lots of individual lithium ions
when the battery was charged.
Everything else
still worked the same.
Discharging the battery sent
the ions through the electrolyte
over to the positive electrode.
Recharging the battery
sent them back.
But now, at least in theory,
all the welcoming spaces
in the layers of the negative
electrode stopped them
from piling up
into dangerous dendrites.
That meant lithium-ion batteries
were far safer
than lithium-metal ones.
But at a price.
They stored far less energy.
REPORTER:
The FAA has long warned airlines
of the potential dangers
presented by lithium batteries.
POGUE:
And safer doesn't mean
completely safe.
REPORTER:
Lithium-ion batteries
have already been linked
to numerous cargo crashes.
POGUE:
All those battery fires
you've been hearing about
in recent years?
Those are lithium-ion batteries.
To learn more about what really
goes into a lithium-ion battery,
I traveled to Ann Arbor
to check out the University
of Michigan's battery lab,
part of its Energy Institute.
Senior lab manager Greg Less has
offered to show me around,
and even build one with me.
Turns out lithium-ion batteries
come in different shapes.
Okay, so this we've seen before,
this is like a watch battery.
Right.
This is a little bigger
than the standard double A.
LESS:
Absolutely, that's a 18650.
And you might find that
in a rechargeable
power tool,
an older model laptop,
or the Tesla Roadster.
But I've never seen this
in a power tool.
Well, no, there's actually
a bunch of them in there,
maybe six or seven, put together
in series inside of that brick
that you plug into
the bottom of the tool.
Oh, okay.
And this--
what, for a phone?
Yup, you'd find a battery
like that either in your phone
or a laptop or
a tablet computer device.
And you actually made
all these in this room?
Yes, we sure did.
That's cool.
Walk me through it,
good sir.
I happily will.
POGUE:
Greg gives me a whirlwind tour
of the process
of making an 18650.
He mixes up the ingredients
for the electrode material,
which gets baked onto foil
and sliced into smaller rolls.
Then we enter through an airlock
into a special low-humidity
dry room.
Any moisture from water inside
a lithium-ion battery
harms the electrolyte.
Once inside...
Here we go!
...we put the rolls on this
crazy machine,
which winds them together
with a roll of plastic separator
into a "jelly roll."
Let's take a closer look.
So we have a top layer
that's the separator.
Yeah.
We'll pull that off.
Then we have our copper and
graphite negative electrode.
Another layer of separator here,
and then the positive
electrode layer
that we made together
of lithium-nickel-manganese-
cobalt oxide.
So every lithium-ion
battery
that's in one of
those cylinders,
including the ones
that are bundled together
to make laptop batteries
and power drill batteries,
they're all at heart
a bunch of these ribbons?
That's correct.
Wow.
POGUE:
After sticking the roll
into a metal can,
Greg injects the last
key ingredient,
the liquid electrolyte.
LESS:
The electrolyte is
the cream
in the jellyroll.
It's what connects
everything together.
The electrolyte is a liquid
solution that has lithium ions
dissolved in it,
and when we charge or discharge
the battery,
the electrolyte is what allows
those ions to travel back
and forth
between the positive
and negative electrodes.
(beeping)
POGUE:
With the final steps of welding,
and crimping the top onto
the metal can, we were done.
Somehow I expected more.
Because it's batteries
like the 18650
or one of the other lithium-ion
styles like these flat ones
in pouches, that will determine
if electric cars
are a viable option
to replace gas-burning ones.
So far in the U.S.,
plug-in electric cars
haven't had much success.
In 2015, they made up
less than one percent
of all new car sales.
VENKAT SRINIVASAN:
There are a few reasons
to be skeptical
of electric cars.
Probably the biggest one
is cost.
But costs of electric car
batteries
are coming down dramatically,
and they'll continue to come
down for the next five years.
They're going to find out that
more and more people can afford
to buy an electric car.
So that problem is getting
solved as we speak.
(bell rings)
POGUE:
The other concern
is called range anxiety--
how far can you go
on a single charge?
Surveys show Americans want to
be able to go hundreds of miles,
even though the average daily
auto use is only around 40.
But there is some justification.
For most of the country,
roadside charging stations
are few and far between.
Despite lackluster sales,
car makers continue to test
the waters,
with lower prices
and longer ranges.
Like the Chevy Bolt,
the first moderately priced
all-electric car
with a range
of more than 200 miles.
Or the new Tesla Model 3, which
has a similar price and range.
Anticipating a large demand,
Tesla plans to produce
500,000 cars a year
in the latter half
of the decade.
But that would require
the entire current
worldwide production
of lithium-ion batteries.
So they've built this:
the Gigafactory in Nevada.
When it's completed,
it will cover more land
than any building in the world,
and it will produce batteries,
"faster than bullets
from a machine gun."
So this is the...
I stop in at Tesla's Palo Alto
headquarters
to find out where all those
batteries fit
in the current Tesla Model S.
So the battery pack
actually runs the length
and the width of the vehicle,
so what you're seeing right
under here is our battery pack.
Oh, the batteries
are already in here?
The batteries are in here.
Now if I could go in there with
a screwdriver and rip that open,
what would the actual
batteries look like?
Are they just a whole bunch
of little double As?
They're little cells, yes.
So we've got about 8,000
individual cells in there.
8,000?
Yes.
And do, by any chance,
do they look like this?
POGUE:
In fact they do.
Early on, Tesla standardized
on the 18650
because of its availability.
But at the Gigafactory, they'll
switch to a bigger version,
which they claim is the best
and cheapest in the world.
Other electric car makers prefer
the flatter pouch batteries,
like those made here for GM
at LG Chem's plant
in Holland, Michigan.
While I was there, I stopped in
to see Denise Gray.
She's the president and CEO
of an LG Chem subsidiary
that does battery research
and design.
So we've heard for years that
electric cars are coming soon.
But are they finally,
at least almost, here?
POGUE:
This plant makes exclusively
batteries for
electric cars, right?
Like are electric cars
becoming a thing?
Yes, they are. Yes, they are.
We're still in the early
stages, but we're making
great progress and I think we
are accelerating down that plan
of having more and more
electrified powertrains
on the road.
POGUE:
How many Americans will buy
electric cars, or how soon,
remains to be seen,
but with more and more
electric vehicles on the road,
engineers are racing to make
the lithium-ion batteries
they contain even better--
cheaper to produce, longer
lasting, and, most importantly,
safer.
I travel to New Mexico
to visit the Sandia National
Laboratories.
Scientists Leigh Anna Steele
and Josh Lamb
show me the battery abuse
testing lab.
Here they do all the things
those warning labels tell you
not to do with batteries
to understand how they fail.
They take me past
a two-ton blast door
to the testing
torture chambers,
where they puncture, overcharge,
burn, short-circuit,
and drown batteries.
The walls, ceilings,
and floors of this building
are all made out of concrete,
reinforced with rebar,
anywhere from 12
to 14 inches thick.
POGUE:
Today they're performing
a crush test,
where they'll slowly smash
the middle of a battery
with up to 15,000 pounds
of force,
the sort of thing that could
happen in an electric car crash.
This is
a hydraulic lift here.
So, it's going to actually
start lifting up
and that impactor there is going
to start crushing the battery.
POGUE:
After a final check of the
setup, we are ready to go.
Okay, Chris, are we ready
to start the test?
All right.
Test is going now, it sounds
like, so we can hear...
we heard hydraulics just
turned on a little bit.
POGUE:
On the hydraulic lift,
the battery slowly rises
into the plunger.
You can start seeing
the gap is starting to close
in between the plunger
and the battery.
POGUE:
You can see the plunger is
crushing the inner battery cells
a surprising amount,
still with no reaction.
But we're getting close.
So you'll start hearing
some hissing.
That's the battery venting
when it actually starts
to go into failure.
(hissing)
(Pogue guffaws)
POGUE:
That's why we weren't
standing in that room.
STEELE:
Exactly.
LAMB:
So all that energy that's
stored in that battery,
it's just discharging
all at once.
POGUE:
When a lithium-ion battery cell
uncontrollably overheats,
it's called "thermal runaway."
Leigh Anna and Josh
break it down for me.
The plunger crushed the
inner cells of the battery
until a negative and positive
electrode made contact--
a short circuit.
Just like when dendrites
short out a battery,
electrons flooded across
in a massive discharge,
creating heat, which then turned
some of the liquid electrolyte
into gas.
That burst open the battery's
foil pouch,
and then the vaporized
electrolyte ignited.
That's known
as venting with flame.
All the fire and heat set off
reactions in other nearby cells,
sending them
into thermal runaway as well.
In the end, the fire
reached a temperature
of over 1,800 degrees
Fahrenheit,
easily hot enough to melt the
aluminum used in the battery.
Leigh Anna and Josh show me
some video of other tests.
This is a battery
that's getting overcharged.
And this is a nail going into
the center of a group of 18650s.
The center cell fails,
gradually taking down
the rest of them with it.
(popping, sizzling)
From the videos,
and having seen it here myself,
one thing seems obvious:
if there were a way to get rid
of the vaporizing flammable
electrolyte,
that would be a big step
toward making these
batteries safer.
And I'm not the only one
who thinks so.
Meet Mike Zimmerman.
He's a Tufts University
professor
and materials scientist.
About five years ago
he got interested
in lithium-ion batteries,
thinking there had to be
a safer electrolyte.
Mike's background is in plastics
and I've come to take a look
at what he's invented.
So this is your battery.
That's the battery.
It looks like any other lithium
battery inside one of these.
It's the same.
Okay.
Same format.
Same voltage?
Same voltage.
You think this is
an unusual battery?
It's a battery
that is much safer
than conventional batteries.
And upon any damage,
any puncture, any cutting it,
it will not catch on fire.
Did you say,
"Any cutting it?"
Correct.
(laughs)
Can I make a cut in this?
Yes.
Really?
Yes.
It's not going to
jet fire into my face?
It will not.
POGUE:
Before I do that, let's consider
these examples from YouTube
of folks poking
at lithium-ion batteries.
They reveal that
it doesn't take much
to create a dangerous
short circuit...
(explosion)
...with disastrous results.
(hissing)
And now, is it my turn?
Big or little?
Whatever you want.
I'm alive!
Wow.
Look at that!
And guess what,
the lights are still on.
This is like a Houdini thing.
I mean, this is like
I'm going to make a doily.
Oh, my God, it's still on!
Come on!
I'm going to make
you a little paper doll.
POGUE:
So what's the trick?
Compared to a typical
lithium-ion battery,
Mike's replaced the liquid
electrolyte and the separator
with his special plastic
to create a completely
solid battery.
Unlike the liquid electrolyte,
which easily catches fire,
Mike's plastic
is flame-retardant.
And even though it's solid,
amazingly, it allows lithium
ions to pass through it
at a rate equal to
or better than
the current liquid electrolytes.
And here's the best part:
the plastic physically
prevents dendrites
from shorting out the battery.
That means that Mike can go back
to a lithium metal
negative electrode,
potentially doubling his
battery's energy density.
Here's another demo
using an iPad
with its original battery
removed and in its place
one of Mike's that's even bigger
than the last one cut to pieces.
And I'm going to stick
a screwdriver through it
like you saw
in those YouTube videos.
Here we go.
So far I'm not seein.
Okay, you've done it,
you've made a battery that
doesn't explode when pierced.
Uh, at the very least I would
expect to see some smoke.
I would expect
to feel some heat.
There's nothing.
Yeah.
It's because of the solid
plastic electrolyte.
It's not flammable.
And it's very insulative.
It doesn't get too hot
and it doesn't burn.
And it keeps working!
Well, that was
an unintended consequence.
Can I do it again?
My mortgage is too high!
And the tax rates
are insane!
And I dented my fender!
All right, now it's not
going to turn on now.
Oh, come on!
Come on!
Oh!
That's it.
A damaged battery.
And yet no smoke,
no flame, no sparks.
Do not try this
with your iPad battery.
POGUE:
So far, Mike's kept
his company's work
mostly under wraps.
This, in fact, is the first
television interview
he's given on it.
But there's still more
development to go
before your new smartphone
makes use of it.
And if I were one
of your critics,
certainly there
would be something
I would attack you for.
There's got to
be something.
It can't be too good
to be true.
Right.
I think that development,
you know, is never done.
We have to do a lot
of reliability testing,
and the scaling up
aspect of this,
it's going to be a lot
of work to scale it up.
So we've got to work with people
that want to do that
and want to introduce a true
next-generation battery.
will come to market
anytime soon is hard to know.
If it does, and if it can double
the energy density
of the batteries
in electric cars,
that would be revolutionary.
But electrifying cars
as a strategy
to battle climate change
comes with a big caveat.
To have real impact,
the source of their electricity
needs to be green as well.
And that means cleaning up
the grid that charges them.
If you're like me, you don't
even think about it.
You flip on a light switch
or you turn on something plugged
into the wall,
where does the electricity
come from?
When was it created?
How does it arrive at your house
at exactly the right time?
How does the electrical grid
work?
KAMMEN:
The grid has been called
the most complex machine
humans have ever built.
It is the largest,
the most extensive,
has the most parts,
and it also has
a beautiful simplicity.
It's driven by this very simple
"energy in must equal energy out
at every moment in time."
You have to generate electricity
over here at the power station
at exactly and instantaneously
the same rate
that you use it over here
on all the customers.
Electricity is essentially
instantaneous.
So, it's a fraction of a
millisecond or microsecond old
because it travels basically
at a fraction
of the speed of light
across the wire.
So we have to make it
instantaneously.
The moment you want it,
I have to make it.
(electric buzzing)
POGUE:
Matching the demand means
constantly ramping up and down
the amount of electricity
generated--
for example, by turning up or
down gas-fed power plants
or spilling more water
over dams,
or even firing up
an old diesel plant
just to meet an hour
of peak demand.
It's a constant,
complicated dance.
Now as we try to shift away
from power plants
running fossil fuels,
the complicated dance that
matches generation with demand
has found some new partners--
renewables, like wind and solar.
They can range in size
from a huge wind farm
generating hundreds
of megawatts of power,
to the small solar array
on your neighbor's house.
The dance just got
more complicated.
CONZELMANN:
We're taking a complicated
system
and making it a lot more
complicated.
We have to be able to meet
the demand still
when the sun doesn't shine,
when the clouds come through
and the output falls,
when the wind dies down.
POGUE:
If these new renewable
but intermittent
sources of electricity
are going to play a major role
on the grid, they require
a new player: energy storage.
I don't think renewable
penetration can go higher
without a robust energy storage
solution, that's for sure.
POGUE:
In the U.S., there's already
a little energy storage
on the grid,
equal to about two percent
of our generating capacity.
Most of it looks
like this reservoir
in Bath County, Virginia.
It's been called the largest
battery in the world.
But it's not like
any battery you've seen.
The system is called
"pumped hydro"
and it operates like a
rechargeable hydro-electric dam.
During the day, when there's
high demand for power,
the electric company lets
the water flow
from an upper reservoir
to a lower one,
spinning turbines
and generating electricity.
But at night,
when there's low demand,
they use the excess electricity
generated by other plants
to pump water back up
to the higher reservoir,
recharging it.
Today, about 99% of all grid
storage in the United States
is pumped hydro.
It would be a relatively
inexpensive way
to store excess energy from
renewables for later use,
except for one problem.
You need the right geography
for the site
with changes in elevation.
And even then,
creating new ones can raise
environmental concerns.
So the search for solutions for
grid energy storage is still on.
Just outside San Francisco
in the Bay Area,
one company is giving it their
own spin-- Amber Kinetics.
They sell an energy-storage
system built around
massive spinning disks
called flywheels.
The principle is simple:
Electricity powers a motor that
spins up the heavy flywheel.
Now, energy is stored
in the flywheel's momentum.
To convert that back
into electricity,
the flywheel engages
a generator,
its momentum turning
the generator's shaft.
As the flywheel slows, the
generator creates electricity.
Needing both weight
and strength,
Amber Kinetics makes their
flywheel out of steel.
How much do these babies weigh?
This is about
a 5,000-pound rt.
Wow, and how fast is it
going to be spinning?
It's some good number
of thousands of RPM.
POGUE:
In a finished unit,
the flywheel sits inside
a welded steel chamber
that tightly seals shut,
so it can spin in a near vacuum
to reduce friction with the air.
They also reduce friction
using a giant magnet
mounted above the flywheel,
which lifts it upward,
removing most of its weight,
so it rests only lightly
on its support bearings.
SANDERS:
And so the friction
in the mechanical bearing
is partly determined
by how much force
is the bearing supporting.
And so we make the force
extremely light.
POGUE:
All of this adds up
to breaking new ground.
Flywheels have been used
on the grid before,
but mostly to store energy
only for seconds or minutes.
Amber Kinetics' flywheels can
store energy
for up to four hours--
for example, capturing
the energy generated
by a solar array durin
the day for use in the evening,
a process called time shifting.
Seth shows me
what a nearly complete
flywheel unit looks like.
There's a flywheel in here
that you made.
But is it spinning right now?
No, it's at rest now.
Okay, if it were spinning,
would I hear it?
You would not be
able to hear it,
because the part is balanced
to a very high degree,
and the residual vibration
is minuscule.
POGUE:
As a grid storage solution,
flywheels, a kind of
electro-mechanical battery,
have an advantage
over chemical batteries.
They don't wear out for decades.
The same can't be said
for lithium-ion batteries,
but there are a lot of those
getting put to work
on the grid as well.
This is Tehachapi, California,
near the Mojave Desert,
home to some of the oldest
and largest wind farms
in the country.
But the wind blows
strongest at night,
when demand for electricity
is at its lowest.
In 2014, Southern California
Edison installed
a $50 million energy
storage system
that uses lithium-ion batteries.
What we want to do is be able
to use this to smooth out,
firm up the output of those so
it's much more predictable.
For example, when the wind blows
during the nighttime,
capture that energy and then
use it during the daytime
when the demand is high.
POGUE:
Lithium-ion batteries have made
inroads into grid storage,
but they're still expensive.
And part of the premium paid
is for their light weight,
which matters for electric cars
and portable electronics,
but maybe not for the grid.
Here in the Pittsburgh area,
battery scientist Jay Whitacre
has taken a different approach.
He's sacrificed lithium ion's
lightweight portability
to create a battery that is
cheaper and safer.
It's nicknamed
the saltwater battery.
We're going to retrace his
steps, starting at square one:
the periodic table.
Ra-Ba-La.
Er...
All right, so these are the
elements that make up our world.
Mm-hmm.
POGUE:
Which elements can you use to
make a battery?
WHITACRE:
Really, almost any of them.
If they have any reaction
potential at all,
you can make electrodes out of
them and they'll store energy.
That's not that hard.
But that's not really the
question you want to ask, right?
You want to ask
which of these elements
can we use
to really scale large,
like really big energy storage
to solve the world's
problems, right?
And to answer that question, we
really get rid of most of this.
Like this...
this is is gone.
We slide this out.
And then we start thinking about
what's called crustal abundance.
Crustal abundance?
Crustal abundance.
POGUE:
Crustal abundance is an estimate
of the availability
of an element in the earth's
outer layer, itsrust.
The higher the percentage,
the more available it is,
which translates into cheaper
and probably better
for the environment
since it's more common.
So if you can pick from crustily
abundant materials or elements,
you're probably going
to have the best shot
at having a low-cost,
environmentally safe battery.
I'm always in favor
of crustily abundant.
WHITACRE:
So, silicon.
These will not surprise you.
You have carbon, you have
hydrogen, you have zinc.
These are in no
particular order,
but you'll recognize
all of them.
They're very
common materials.
They make up everyday life.
Oxygen and a couple
of really important ones.
You've got sodium,
which is, obviously,
everywhere in the ocean.
You've got potassium, which
is a heavy biological factor,
and lithium, which you might not
think is crustily abundant
but actually is.
And these were the ones that
I started looking at in 2007
when I was trying to figure out
what elements I would use
to put together in any which way
to create something
that was going to be functional.
POGUE:
Out of this initial collection
of elements,
Jay created a battery
that had a sodium manganese
oxide positive electrode
and a carbon negative electrode.
When the battery was charged,
sodium ions left the positive
electrode to gather
at the negative
carbon electrode.
When discharged,
they would return
to the positive electrode.
With each charge and discharge,
they shuttled back and forth.
The electrolyte, sodium sulfate
salt dissolved in water,
gave the battery its nickname--
the saltwater battery.
From there, Jay began
tweaking his recipe.
The end result was a battery
far less energy dense
than lithium ion
but non-flammable,
non-toxic and cheaper.
WHITACRE:
So this is a barrel
of our active material.
This happens to be
our cathode material.
It's a manganese oxide base
system, and it's really simple.
It basically looks
like dark sand or dark dirt.
Listen, Jay, I've been to a few
battery factories in my time.
I'm sure you have.
And I've never been allowed
to walk up to a barrel
in a non-humidity-
controlled room.
No, well, the key difference
between this battery
and probably all
the others you've visited
is that we use water
as an electrolyte.
POGUE:
Water changes everything
in a battery.
On the downside,
it limits the voltage.
Too high and the water splits
into hydrogen and oxygen gas.
But it also means you don't need
the expensive low-humidity
dry rooms
required to make
lithium-ion batteries.
And, of course,
water is nonflammable.
Safer.
In fact, the salts that we use
as electrolyte salts
are flame inhibitors.
Is this toxic, this thing here?
This is not toxic at all.
I could eat this
cathode material?
It is biologically
consumable, yeah.
I wouldn't recommend it.
It's going to taste
a little salty to you,
a little weird but yeah.
There you go.
Mmm, pumpkin spice.
Yeah, it's totally fine.
It's not even salty.
No, it's just like sand.
Yeah.
It is basically sand.
It's actually a little
better than sand,
as a frequent sand eater.
POGUE:
These days, Aquion Energy
is churning out batteries
in a former Sony Trinitron
factory outside of Pittsburgh.
Here, Jay's emphasis on safe
ingredients saves a lot of money
in manufacturing.
The electrode material
I taste-tested is pressed
into cookie-like wafers,
which in turn get assembled
by these pick-and-place machines
from the food industry,
used in packaging.
All without the tight humidity
and dust controls
found in lithium-ion
battery factories.
Already, saltwater batteries
are part
of hundreds of solar
installations around the world,
ranging from utility projects
to individual homes.
But Jay sees himself
at the beginning
of a massive undertaking:
to bring energy storage
to the grid.
WHITACRE:
This is not a small-scale
project.
Like, to get storage to be
relevant in the world,
you have to make
huge amounts of it,
and this is just
a drop in the bucket.
We're just getting started.
POGUE:
On that, everyone agrees.
If we want energy storage
to integrate renewables
into the grid, we're woefully
short on quantity.
In 2010, Bill Gates noted that
all the batteries on earth
could store less
than ten minutes
of the world's electricity
production.
To fill the gap,
we'll need systems that can
scale up easily.
Levi Thompson
at the University of Michigan
introduces me to one--
a rechargeable battery unlike
any other: the flow battery.
He explains that a typical
battery is a closed system.
And this is all sealed.
Okay.
So, everything that you need
is in there.
It's like a cake.
You put everything in there,
you get everything you want.
Every battery kind
of looks like this.
POGUE:
Every battery but a flow
battery, says Thompson.
Instead of a closed system,
a flow battery has external
tanks containing two chemicals.
They're pumped past each other
through a chamber.
Because of a special thin
membrane, they can't mix,
but in close proximity they do
react, generating electricity.
The capacity of a flow battery
depends on the size
of the external tanks
that hold the chemicals.
Bigger tanks, bigger battery,
more energy.
THOMPSON:
Flow systems are,
for large-scale applications,
much more efficient,
much more cost-effective
than sealed systems.
It's a much better solution
to the problem.
Flow batteries will surely
play a role in the grid.
This is what they have always
been designed for
and ought of as
the grid battery.
POGUE:
Some flow batteries
are already in operation,
like this one at Fort Devens,
a U.S. Army installation
in Massachusetts.
The battery helps integrate
solar generation,
reduces peak demand,
and improves power quality.
And research continues,
like the work of these two
members of Levi's team.
It's early days,
but with more development,
flow batteries might just
turn out to be the answer
for grid storage.
This is something
that's shown to work
and people are actually
using it,
but that's not the mind blower
so much as where it could be
in 40 years.
THOMPSON:
Where it could go.
Absolutely.
KAMMEN:
Flow batteries are perhaps
the newest exciting entrant,
but I would expect
over the next decade, there's
going to be a whole series
of these new, exciting entrants
into the field.
POGUE:
So, in the end,
we still don't know if
the grid super battery
will be one technology,
or a mix of pumped hydro,
chemical batteries, flywheels,
flow batteries, and others.
But if we really want
to integrate renewables
into the grid
and trade our carbon-spewing
vehicles for greener ones,
and do it on the massive scale
required to fight
climate change,
one thing's for sure:
energy storage, and lots of it,
will be in our future.
And so will the ongoing
search for the super battery.
This NOVA program is
available on DVD.
NOVA is also available
for download on iTunes.