Kind: captions
Language: en
This is what the inside of a lithium ion
battery looks like. It's not exactly
high-tech, just 2 m of foil coated in
black paste, all packed into this tiny
45 g cylinder. But these are some of the
best batteries we have. They power
everything from laptops and electric
vehicles to orbiting satellites.
Yet, when a battery fails, all that
energy can get released in the wrong
way.
>> Oh my god. the latest incident involving
lithium ion batteries.
>> So, how did something so rudimentary
looking end up in almost every
electronic device on the planet? And why
don't we have anything better? In the
early 1980s, most rechargeable batteries
were stuck at just 40 to 60 W hours per
kilogram, meaning you would need a
kilogram of battery to power a 40 W
light bulb for just an hour. As a
result, when the first commercial mobile
phone launched in 1983, it was pretty
unimpressive. It took 10 hours to charge
for just 30 minutes of talk time.
Laptops, cameras, even medical devices
all suffered from the same bulky
batteries. Everyone from electronics
giants to oil companies were trying to
make a better battery because they knew
that even just doubling the energy
density could unlock a new era of
portable electronics and power the
digital revolution. But what no one
realized is that someone had already
found the solution.
In 1972, a 32-year-old British chemist
named Stanley Whittingham was studying
how different materials store energy at
Exxon's research lab in New Jersey. Yes,
that Exxon, the multinational oil giant,
then the largest oil company in the
world. They were researching batteries.
The next year, war broke out between
Egypt, Syria, and Israel. When the US
backed Israel, Arab oil producers cut
off oil exports in retaliation. And on
December 22nd, the price of crude oil
more than doubled from $512 a barrel to
1165.
In response, President Nixon created
policies to try to keep oil prices down,
but they backfired and the shortage only
got worse. Americans were left queuing
for hours at gas stations as the
government introduced a rationing
program. It got so bad that they even
dropped the national speed limit to 55
mph just to cut consumption.
At Exxon, executives were worried that
supplies would run out entirely. So,
they started looking seriously at
alternatives like electricity.
This wasn't a new idea. In fact, in
1900, when cars were first taking off,
the top selling car was electric, ahead
of steam and gas-powered cars. But the
problem with these electric cars was
their batteries. They weighed 360 kg,
around 40% of the car's weight, but they
could only take you around 60 km. And
the energy density wasn't just low, it
also degraded over time. Every time you
recharged, it got worse. After fewer
than 500 charges, your range would have
dropped to about 40 km. So by 1924, gas
powered cars outnumbered electric 10,000
to1.
But now that the oil supplies were
running out, it seemed to Exxon that
there was no other solution than to
bring back the electric car. And to do
that, they needed a battery with a much
higher energy density. So suddenly,
Whittingham's side project became a top
priority. Exxon poured in resources,
giving him free reign to, in his words,
do pretty much what I wanted, as long as
it did not involve petroleum.
The very first battery dates back to a
curious incident in the 1780s when
Italian scientist Luigi Galvveni was
dissecting a frog to study its anatomy.
He anchored one side of the frog on a
brass hook and went to cut it open with
a steel scalpel. But when he touched the
scalpel to the frog's leg, he noticed it
suddenly twitched, as if it had come
back to life. Galvani believed he
discovered a sort of animal electricity,
a living force produced by the tissue
itself. But Galvani's rival, Aleandro
Volulta, disagreed. He thought it came
from the metals themselves. And you can
see this with lots of different
materials. Veritassium producer, Gregor,
set up a version of this experiment,
minus the frog, to test it out. I have
zinc, magnesium, and iron here. I can
take any of these metals, stick them
into one side of a lemon, and stick some
copper on the other side. If I hook
these up to a voltmeter, I should be
getting a voltage, and we got around 0.8
volts. Now, the reason this happens is
because some elements want to get rid of
their electrons more than others. So if
you pair one that really doesn't want
its electrons with one that really wants
some, well then the electrons are going
to be traveling across. Let's look at
the zinc. What's happening here is that
zinc is losing its electrons. The zinc
ions enter the juice and the electrons
are forced to go through the circuit to
get to the other side. There hydrogen
ions in the lemon juice want those
electrons so they receive them and turn
into hydrogen gas.
You've got one side that gives up
electrons. That's the anode. and you've
got one that receives them. That's the
cathode. But why do you need the lemon
at all? If there's no flow of the
positive ions through to the other side,
the electrons stop moving almost
immediately. This happens because all of
the electrons now get bunched up in the
copper, making it extremely negatively
charged, and that is just going to push
away any more electrons from coming over
to the other side. That's because
electrons can't travel through lemon
juice. Liquids like this don't have free
electrons the way metals do. So
electrons stay in the wire. They'll only
leave the circuit at the copper side if
there's something in the juice like
hydrogen ions ready to take them and if
the reaction releases enough energy to
make that transfer happen. But positive
ions in the juice can move. They travel
across to balance the charge allowing
the current to keep flowing. A solution
that carries charge this way by moving
ions is called an electrolyte.
But we could also do this with the other
metals to get a similar reaction. And we
can actually quantify how much each of
these metals wants or doesn't want
electrons. With zinc, we already got
around 0.9 volt. But if you try it with
iron, for example, you get something
lower, 0.5 or 0.6 V. Now, magnesium is
tricky and it would be a bit higher. But
it oxidizes so quickly that even if I
scrape some of the oxide from the
surface, I'm still getting only around
0.7
vol.
The idea is that the larger the voltage
on the voltmeter, the more energy each
electron has to give as it passes
through the circuit. But there's also a
limit to this. See, this beaker is full
of lemon juice from the lemons we used
earlier. And they're hooked up using
spoons and these wires to a variable
power source. Now, look what happens
when I up the voltage.
You'll actually start to see bubbles
forming on both spoons. And that's water
in the lemon juice actually being broken
down into oxygen and hydrogen gas.
This already starts happening at 1.23
volts. And that sets a limit on how much
voltage you can push through this
electrolyte.
Up until the early 1970s, just about
every commercial battery used a
water-based electrolyte. And as a
result, none of these battery cells
could push much beyond the 1.23 volt
limit. Now the total energy a battery
can store depends on how much energy
each charge has to give times how much
charge can move. That is the battery's
voltage times its capacity. So if you
can't increase the voltage your only
option is to make more battery more
cells or bigger cells. But that won't
increase the energy density.
And this is exactly the problem
Whittingham was trying to solve. He was
searching for materials that could store
large amounts of energy in a compact
space with light weight. That led him to
a class of compounds called transition
metal dicalcenides.
He zeroed in on one in particular,
titanium dulfide. Titanium in this
compound has effectively lost four
electrons, two to each sulfur atom,
meaning it sits at a plus4 oxidation
state. That leaves it very electron
hungry. Exactly what you want in a
battery cathode. But titanium dulfide
has a second key advantage. This
material is made of stacked layers held
together by weak Vanderwal's forces.
This creates natural gaps between sheets
of titanium and sulfur atoms just wide
enough to let certain ions slip between
the layers, a process known as
intercolation.
Better still, the structure can expand
and contract repeatedly without breaking
down. Now Whittingham just had to decide
which ions to use.
He initially looked at potassium, but it
was just too reactive and far too
dangerous to work with. Oh yeah.
He turned to this, a soft silvery metal
called lithium.
What makes lithium unique is not the
fact that it has one electron in its
outer shell that it wants to get rid of.
No, that it shares with the other
elements in its group. What sets it
apart is how much energy you can get out
of lithium when it reacts in a battery.
See, when it loses that outer electron,
it forms a tiny, incredibly stable
positive ion. And so that reaction
paired with the right cathode releases
more energy per electron than any other
metal. That's why it produces the
highest voltage of any metal used in
batteries. And because it's so small
with just three protons, lithium is also
the least dense metal at just 0.53 g per
cm. This combination of low density and
the tendency to give away its electron
made lithium perfect for Whittingham's
vision of this high energy density
battery. But while lithium was easier to
work with than potassium, easier still
didn't mean easy. I mean, they only let
me hold it in this glove box. And matter
of fact, here's what happens to lithium
if you put it in a glass of water.
[Music]
Safe to say you don't want this
happening inside your battery.
So Whittingham had to switch out the
water-based electrolyte for something
else. And that change unlocked the
possibility of higher voltages. He
turned to a solution of lithium salt in
an organic solvent. And it worked. But
it came with serious risks. The solvent
was volatile. The lithium salt was
chemically unstable. Together, they
formed a mixture that could explode or
release toxic fumes if mishandled.
Everything had to be done with extreme
caution. A stray spark or a trace of
moisture could destroy the experiment or
start a fire. But if you could get
around the danger, this new electrolyte
was a huge perk. It let lithium ions
shuttle between electrodes without
breaking down the solvent or the cell.
At least not until much higher voltages.
Whittingham had unlocked lithium's
potential, and in the process, he'd
broken through the 1.23V ceiling. His
new chemistry delivered nearly double a
huge 2.4 volts per cell. He now had a
working prototype, a metallic lithium
anode on one side, a titanium dulfide
cathode on the other, his new liquid
electrolyte in between. There was also a
thin porous separator that kept the
electrodes apart so they couldn't touch
and shortcircuit. Here's how it works.
When you close the circuit, lithium
atoms at the anode give up their
electrons. Those electrons travel
through the external circuit toward the
cathode, generating a current that
powers whatever's connected. At the same
time, the lithium ions are released into
the electrolyte, and then they pass
through the porous separator and migrate
toward the cathode. The electrons
arriving through the circuit are taken
up by the titanium atoms in the titanium
dulfide. The positive lithium ions slide
between the layers to balance out the
negative charge of the electrons and
they become locked in place. And this
process is reversible when you apply a
voltage to recharge. The extra electrons
are stripped from the titanium and
pulled back to the anode. The lithium
ions are forced out of the titanium
dulfide layers into the electrolyte and
they too migrate to the anode where
metallic lithium reforms. What
Whittingham had created here was a
rechargeable battery, one that worked
reliably cycle after cycle with
incredible consistency.
I don't normally think about batteries
this way, but what they really are is
tiny little contained chemical
reactions. And in a chemical reaction,
if you could get a 60% yield, that would
be considered good. But in a battery,
especially one that you want to recharge
a thousand times, you need that reaction
to be say 99.9%
efficient because if it's not, the
capacity of that battery rapidly
deteriorates. If you have, say, a 95%
yield, then you'd lose a significant
fraction of lithium ions every cycle.
After just 50 cycles, you'd only have 8%
of your original capacity left. So, it's
pretty incredible that every single
lithium ion has to leave one electrode,
pass through the electrolyte, and slot
neatly into the layered crystal
structure of titanium dulfide, and then
when you recharge it, they have to leave
again cleanly, without incident, without
getting stuck, make their way all the
way back to the anode. Amazingly,
despite just being an early prototype,
Whittingham's battery came close to that
99%.
[Applause]
In the winter of 1973, Exxon's managers
summoned Whittingham to the company's
New York office.
Whittingham later said, "I went in there
and explained it 5 minutes, 10 minutes
at the most, and within a week, they
said yes, they wanted to invest in
this."
They got to work at the Exxon
laboratory, but it wasn't all smooth
sailing. Firefighters had to be called
out repeatedly. They were called so
often they threatened to start charging
the lab for the special chemicals needed
to extinguish the burning lithium.
>> The problem was the anode. Whittingham's
design used pure lithium, which worked
brilliantly until it didn't.
>> We've made a special cell. We made a
transparent battery.
>> So cool.
>> But they're very very small. So we have
a a microscope lens just to allow us to
see it.
>> What you're seeing here is a piece of
copper which we're gradually plating
with lithium. So this is analogous to
the first generation lithium uh metal
batteries which used lithium metal as
the anode. On this side we have a piece
of lithium. As we charge the battery
we're stripping the lithium from that
electrode and we're plating it. And
actually what happening right now is the
ideal reaction where it's very slow.
We're getting a dense plate. The
challenge then becomes if we go too
fast.
>> Oh that is huge.
Everything's fine until all of a sudden
it's not fine. So we want the lithium to
play evenly across everywhere, but
instead it forms in that one location
and that is what is a lithium dendrite.
That lithium dendrite can grow. The
length scales of this is on the order of
um you know millime. So that would have
easily shortcircuited the battery
>> and that dendrite can just keep growing
and eventually it's going to poke
through the separator and reach to the
other side. Now the electrons are going
to have a shortcut. So instead of going
through the circuit, they race straight
from the anode to the cathode using the
dendrite. And that sudden surge of
electrons cause intense heating and that
can trigger a chain reaction inside the
battery leading to a fire or even an
explosion.
For all its promise, Whittingham's
battery was just too dangerous, and then
the oil crisis ended. Prices dropped,
and Exxon's urgency evaporated. The
company shut down its lithium battery
program. Whittingham published his
design in 1976, and Exxon licensed the
patent to a few manufacturers. But with
no funding and no momentum, the first
lithium battery revolution died before
it had a chance to take off.
Fortunately, a copy of Whittingham's
paper made it across the Atlantic to
Oxford University in England, where it
caught the attention of John B. Good
enough, an American physicist leading a
solid state chemistry group.
As he read the paper, one thing stood
out. The cell voltage was being held
back. The material Whittingham chose for
the cathode, titanium dulfide, capped
the cell at just 2.4 V. But good enough
believed that with a better cathode
material, he could do better.
He had previously worked with compounds
called transition metal oxides. They
were more stable than sulfides, and some
he knew were extremely hungry for
electrons, perfect for a cathode. He
tried one of these compounds in his
battery, and the voltage immediately
spiked from 2.4 volt to 4 V. This jump
was incredible. But what was even more
surprising was the fact that this
compound already had lithium in it. The
material was lithium cobalt oxide.
Lithium cobalt oxide is arranged so that
the cobalt and oxygen atoms form tightly
bonded layers with lithium ions nestled
in between. This means that your supply
of lithium ions doesn't just have to
come from the dangerous lithium metal on
the anode side. It's already there
pre-built into the cathode. So
theoretically, you don't even need
lithium metal at all. You could assemble
the cell in a discharged state with all
your lithium ions in the cathode. Then
when you connect it to a charger, these
ions will get expelled from the cathode
crystal lattice and into the
electrolyte. At the same time, nearby
cobalt atoms will give up an electron to
balance out the charge. And those
electrons then go through the wire to
the anode to meet with the ions. If Good
Enough could find an anode that would
replace lithium metal, the battery would
become safe enough to leave the lab and
actually power real world devices.
Good enough was so excited about the
potential of his design that he reached
out to battery companies across the US,
the UK, and Europe. But incredibly, no
one was interested. So he asked Oxford
to file a patent, but they refused. So
he took it to a government lab near
Oxford, the Atomic Energy Research
Establishment, and finally they agreed
to fund the patent, but only if good
enough signed away his financial rights.
Seeing no other option, he agreed and
the lab patented the invention in 1981.
Now, this should have been a gold mine,
but the lab didn't realize what they
had. And so, for the second time, the
lithium battery revolution was boxed up
and shelved. This should have been a
turning point for battery science, but
bureaucracy and inertia stalled
progress. Every field has its
bottlenecks. For batteries, it was
slowmoving institutions. For developers
today, it's slowmoving code reviews. And
I can relate. When we make these videos,
especially the ones with simulations or
complex animations, it's rarely the
ideas that slow us down. It is the
reviews. Developers face the same thing.
They're writing code faster than ever
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But code reviews, well, they're still
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I would like to thank Coderabbit for
sponsoring this part of the video. And
now back to Good Enough's design, a
breakthrough with nowhere to go yet.
While Good Enough's battery design was
gathering dust, 10,000 km away in Japan,
a 34year-old chemist named Akira Yoshino
was trying to find a safer battery
anode, one that didn't require lithium
metal. Yoshino was actually looking at
plastic. Now, normally plastic is an
insulator, but the kind Yoshino was
looking at is different. It's called
polyacetylene and its carbon atoms are
arranged in a repeating chain of single
and double bonds. A structure that gives
it unusual electronic properties. If you
tweak polyacetylene by adding or
removing electrons, electrons can
actually move along this carbon chain.
So the plastic conducts electricity like
a metal. And that got Yoshino thinking,
what if polyacetylene could work as a
battery anode? During charging, it could
absorb lithium ions and electrons, and
then during discharge, it would give up
those electrons to the circuit, just
like lithium metal does. If it worked,
it could eliminate the most dangerous
part of the battery, the metallic
lithium. But for months, Yoshino
struggled. Obviously, since he removed
lithium metal from the anode, he had to
get lithium ions from somewhere else.
And he couldn't figure it out. And then
just as he was losing hope on the last
workday of 1982 while cleaning out his
office he stumbled upon a 1980 paper by
John B. Good enough. It described a
cathode made of lithium cobalt oxide a
cathode that already contained lithium.
This was the missing piece.
He sketched out the reaction between
lithium cobalt oxide and his
lithium-free anode and then built a test
cell using the two materials. It worked
safely and reliably. But Yoshino wasn't
satisfied. The material he used for the
anode, the polyacetylene, had an
extremely low density. I mean, it it
couldn't pack in enough lithium. So, the
energy density of the battery was
terrible. Yoshino needed something more
lightweight, compact, conductive, and
crucially, something that could
reversibly accept and release lithium
ions within its structure without
breaking down. He tested material after
material and every single one failed
until a breakthrough came from within
his own company. Another team had
developed a new form of carbon with a
unique crystallin structure. They called
it vapor grown carbon fiber. He got his
hands on a sample, tried it in the lab,
and it worked.
To prove it, he placed a test cell
containing metallic lithium into a
safety rake, one that's designed to test
explosives. Then he dropped a heavy iron
rod onto it. It exploded violently. Then
he ran the same test again, but this
time with his new design using carbon as
the anode, he charged the cell, placed
it in the rig, and dropped the rod, but
nothing happened. The contrast was
undeniable.
Later, Yosha would say that was the
moment when the lithium ion battery was
born. But his employer, Asahi Chemical,
well, they weren't a battery company and
they didn't know how to make batteries.
So, in 1986, Asahi executive Iso
Kurabayashi flew to Boston on a top
secret mission carrying three jars
containing cathode, anode, and
electrolyte materials. He handed them to
a tiny firm called Battery Engineering,
working out of a converted truck garage.
and he asked them to turn the materials
into cylindrical cells like the kind you
might buy for a flashlight. The team did
just that, completely unaware of what
they were handling. It wasn't until 2020
that employees learned the truth that
they had helped assemble the world's
first pre-production lithium-ion
batteries.
2 weeks later, Kurbayashi returned to
Japan with 200 finished, perfectly
functioning cells. Even then, Asah's
leadership hesitated. Kerbayashi refused
to give up. On the 21st of January 1987,
he visited Sony and he took one of the
prototype cells and rolled it across the
conference table to the Sony execs. And
at last, they saw its potential. They
reworked the design, swapping out
Yoshino's carbon material for graphite
that could better intercolate lithium
ions between its layers. And in 1991,
Sony launched the first commercial
lithium ion battery inside this, the
Sony Handyam. Their battery was compact,
rechargeable, powerful, and crucially
free of unstable lithium metal. It was
Sony who first coined the name lithium
ion, and it stuck.
But this wasn't just about one
camcorder. Competing companies like
Panasonic and Sano raced to catch up.
Lithium ion batteries started appearing
in phones, CD players, laptops.
manufacturers actually began to
advertise the use of lithium ion
batteries as a key selling point to
their products. I'm showing my age here.
I joined the industry when lithium-ion
cells were first introduced and uh there
was a Sony camcorder that was introduced
and then there was Dell computer and I
still remember the ads when Dell
Computer introduced their lithiumion
battery and they had eight eight hours
of runtime. So they had an advertisement
in a magazine and it was eight pages
long. Each one was an hour longer. So it
was it was a big deal. But what's crazy
is that even after all this, these
batteries should never have worked. See,
when you charge the battery for the
first time, lithium ions move from the
cathode to the graphite anode. And here,
they react with the electrolyte to form
this weird complex patchwork of
compounds that build up on the anode
surface. These parasitic side reactions
should keep going on indefinitely, using
up all the lithium and destroying the
cell. But they don't. Instead, they form
a thin protective layer known as the
solid electrolyte interface or SEI. It's
a kind of chemical shield protecting
both the graphite anode and the
electrolyte from further reactions. But
crucially, lithium ions can still slip
through it. When the SEI originally
forms during the first charging cycle,
around 5% of the lithium in the cell
actually gets stuck in this layer,
decreasing the battery's capacity. But
this little trade-off is what makes the
battery stable enough to be used for
years or even decades. Which is why
today lithium ion batteries are
virtually everywhere.
From 1991 to 2023, the price per
kilowatth dropped by 99% from nearly
$9,000 to just $100. At the same time,
energy density and cycle life, how many
times a battery can be charged and
discharged before it wears out, improved
dramatically, crossing a critical
threshold. Lithium ion batteries had
become powerful enough and finally cheap
enough for something bigger, the return
of the electric car.
Today, lithium ion powers a 100 billion
industry. In 2019, Whittingham, Good
Enough, and Yoshino finally received the
Nobel Prize in Chemistry for an
invention that, in the committee's
words, revolutionized our way of life.
This made Good Enough the oldest Nobel
laurate in history, receiving the award
at the age of 97.
But lithium ion isn't perfect.
>> Scary moments aboard a jet blue plane. A
fire erupting after a passenger's
backpack suddenly exploded.
>> Every week inside an airplane, there is
at least one event of a battery of a
phone of an iPad or a toy or something
that has catching fire.
>> What? Every week there's
>> Yeah, every week.
>> It's just the latest incident aboard a
plane involving lithium ion batteries.
So far this year, 60 onboard battery
incidents through early October. Every
flight in the US has a bag, a
specialized bag which very thick um
nonflammable materials where you put the
phone inside and you close it and you
still have a hazard and you have to deal
with this gases but now you you have put
the fire ignition away from anything
else and if it burst into fireworks uh
then at least it's in a container and
then you tell the captain we we need to
land immediately.
>> So what is actually happening when a
battery fails like that? This is a
classic lithium ion battery. And today
we're going to do something I always
wanted to do. We're going to tear one
down.
>> I guess safe to say don't do this at
home. But what would happen if you were
to do this outside of the the glove box?
>> If you charged up the cell and then you
tried to tear it apart, then uh you
could accidentally short it and then it
could uh burn and it could even explode
or fire. If you discharged it and you
opened it up, you'd release all the
different gases and really toxic
chemicals. And if you inhale those, then
you'd probably end up in hospital.
>> So at this point, uh, we have what we
call the jelly roll. So it's a roll of a
cathode separator anode.
>> Yeah.
>> Stuck together with bit of tape. So
Lynn's just going to scalpel off the
tape and then we should be able to
unroll it into a nice sheet.
>> So these little patches are the
electrolyte or
>> Yeah. Okay. So, as time goes by, it will
start evaporating out.
>> That is so cool.
>> It's so obvious when you see it, but I I
don't think anyone intuitively thinks
that it's a rolled up like sheet of
anode and cathode inside. But these
layers inside the battery, they're not
going to stay perfect forever. Here's an
electrode from a new cell compared to
one from an old one. You can see that
the lithium is building up in all the
wrong places. And if this sort of
degradation gets out of hand, well,
we're about to push a cell past its
breaking point.
>> How do we blow up a battery?
>> So, today we've got a prismatic battery.
It's a small battery from sort of a a
power tool or a phone or something
similar. We're going to wrap it in some
nic wire. So, we pass current through
this wire. Something like 200 W we pass
through. That's a lot.
>> This wire. Yeah, it's a significant
battery. We We want it to go and we want
it to go pretty spectacularly.
[Music]
Good luck, Harry.
>> What we're simulating here is a
catastrophic battery failure. The kind
that could happen if a cell is damaged
or overheated or even just badly
manufactured. It starts around 80° C
when the protective SEI layer on the
anode starts to break down. It's going
to try to reform, but these reactions
are going to release more heat. And if
that heat can't escape, the temperature
is going to keep rising.
How close is it to exploding now? What
do you think? It
>> should burst very soon.
>> At roughly 130° C, the polymer separator
is going to melt. And now the anode and
cathode can come into direct contact and
a massive internal short follows. The
cathode itself starts to decompose. And
because transition metal oxides release
oxygen from their crystal structure,
they're going to fuel the combustion.
And now the fire is just feeding itself.
Oh
>> yes.
>> Oh. Oh my god.
>> That's really violent.
>> This is insane. From one small battery
like that.
>> And it's only 50% the state of charge.
>> What we call ignition happens inside the
battery not outside the battery. And it
it it this requires a fuel or a
substance that will undergo a reaction.
It requires an oxidizer or the cub
oxidizer and it requires heat. The
battery contains these three inside. So
it has its own equivalent to an
oxidizer, its own equivalent to a fuel,
and its own source of heat.
>> All of it in in one device.
>> So it's not actually lithium that burns.
A modern lithium ion battery like this
one here contains very little lithium,
ironically. It's actually everything
else inside here that's dangerous.
It must be really hard putting out a
battery fire if it really has everything
it needs.
>> Yeah, exactly. So you can still put the
blanket and and stop the oxygen from
arriving but you will not the fire will
not go to zero. It will will still it
will be smaller but it will still be
there.
>> And then with water yeah water has the
ability to take heat away. So it is
possible to take the heat away from the
battery with water. But the best thing
is to put an immersive battery into a
bath of water.
>> Yeah.
>> Uh is brutal. Uh you can do that with
one battery with 10 batteries with 10 15
batteries. But when you have very large
packs of batteries with thousands of
batteries, you cannot physically put
that underwater.
>> Yeah. One thing that is popping up
recently as a threat to cities is
electric car fires.
>> Well, we know a lot of water works.
>> Yeah. Well, if there's a water source
nearby, I guess. Yeah.
>> Yeah. I mean, this is what they do in
some countries around the world. They
have a truck, a specialist truck full of
water, and you just take the car that
has been involved in electric fire and
they dump it into the Yeah, they do. and
and actually it works.
>> So how dangerous is it really?
>> It's very rare. Every million batteries
there is a fire.
>> Okay.
>> Right. So that's very safe that in the
standards of engineering that's like oh
you have a good system one out of a
million that's a fire. But batteries are
everywhere. We don't even think about
it.
>> So within our lifetimes we are going to
reach a point where we would have been
exposed to more than a million
batteries. So we would be all of us
experiencing a fire of a battery.
>> With billions of batteries in
circulation, even rare failures become
inevitable.
Meanwhile, demand is skyrocketing. By
2030, we're projected to need over 17
million tons of batterygrade materials.
And making lithium-ion batteries comes
at a cost. Lithium only makes up around
20 parts per million of Earth's crust.
It's expensive and water intensive to
extract. And 70% of cobalt, another key
ingredient in many lithium ion designs,
comes from the Democratic Republic of
Congo. Much of it mined under hazardous,
often exploitative conditions. We need
more batteries, and we need them fast.
We can't just rely on lithium alone. So,
it's not like lithium is as good as
we're going to get. Like, then we're
going to get much better batteries in
the future. If our priorities are about
saving the planet from runaway climate
change, we need to have massive scale
energy storage system and electrify
almost everything else that we do. The
hunt is still on for safer batteries,
for cheaper ones, ones that last longer,
charge faster, and ones that store far
more energy. The lithium ion battery
changed the world. But the future of
energy storage won't be about just
conquering one element. It'll be about
mastering many.