Speaker 1: Get in touch with technology with tex Stuff from how
Speaker 1: stuff Works dot Com. Hey everyone, and welcome to tech Stuff.
Speaker 1: I'm Jovin Strickland and I'm Lauren Folkebin. Today we're going
Speaker 1: to talk about something that we've tackled in a previous
Speaker 1: episode at least Chris and I did. We're gonna talk
Speaker 1: about batteries and also why have batteries been so slow
Speaker 1: to improve over time? What what could be the future
Speaker 1: of batteries and uh and what are the implications of that.
Speaker 1: This all comes to us courtesy of a listener suggestion.
Speaker 1: David via Twitter said, could we talk about the improvements
Speaker 1: and battery technology and also why battery text seems to
Speaker 1: lag behind other technology when it comes to big leaps.
Speaker 1: It's um, that's a good question. And so you know,
Speaker 1: it's something that a lot of people have commented on
Speaker 1: the fact that you have something called Moore's law. That's
Speaker 1: that observation that in general, microprocessors get twice the number
Speaker 1: of discrete elements, or if you prefer to think of
Speaker 1: it in another way, microprocessors tend to get twice as
Speaker 1: powerful every two years or so. There. Yeah, this is
Speaker 1: not exponential growth, which I have called it in previous episodes,
Speaker 1: by the way, and people right in every time and
Speaker 1: call it take us to task on it, which is
Speaker 1: important because when we get wrong, it's a misuse of
Speaker 1: the word exponential. I'm using it's a colloquial use. But
Speaker 1: I do not want to go down that hole again
Speaker 1: because I'm like you guys, I get irritated when people
Speaker 1: misuse words too. I just wish I didn't do it
Speaker 1: as frequently myself. But anyway, it does double every two
Speaker 1: years or so, and that's a phenomenal amount of growth.
Speaker 1: We're talking about microprocessors that have billions of discrete elements
Speaker 1: on them now, and they're all down at the nanoscale.
Speaker 1: So there's this amazing amount of technology that's been poured
Speaker 1: into microprocessors, partially because Morris law exists and companies strive
Speaker 1: to to keep up with it to maintain it because
Speaker 1: Moore's law, as we know, is not a real physical law.
Speaker 1: It's more of an observation, and companies no one wants
Speaker 1: to be the company that comes up and says, yeah,
Speaker 1: we can't do that. You know, we just got bored.
Speaker 1: So it means that there's been a lot of innovation
Speaker 1: in that space. But meanwhile, on the battery front, batteries
Speaker 1: have in large part remain more or less the same
Speaker 1: for decades. I mean, we've we've seen improvements in battery life,
Speaker 1: we've seen improvements in battery efficiency, but there have been
Speaker 1: some new technologies over the past fifty years. But even so,
Speaker 1: it just hasn't it hasn't at all kept up with
Speaker 1: the microprocessors assessor side. This is also, by the way,
Speaker 1: this ties into our episodes where we talked about things
Speaker 1: like the Singularity, where we talk about how technology doesn't
Speaker 1: all progress at the same rate. So while we do
Speaker 1: see devices getting more and more sophisticated and powerful, the
Speaker 1: power supplies aren't keeping up with that trend. So it
Speaker 1: may be that the Singularity, if it is ever going
Speaker 1: to arrive, is further off than what some people think,
Speaker 1: simply because the power side of the equation is lagging behind, uh,
Speaker 1: the the technological sophistication side. So why is that. Well
Speaker 1: to understand it, we kind of have to one talk
Speaker 1: about what a battery is and to sort of look
Speaker 1: at the history of the development of batteries and talk
Speaker 1: about what exactly it does now. On a very very
Speaker 1: basic level, a battery is something that uses electro chemical
Speaker 1: reactions so that you can guide electrons through a circuit
Speaker 1: and have it do work. And that's about it. Yeah,
Speaker 1: that's that's really all a battery is. And it's because
Speaker 1: there are certain chemicals that when they have these reactions,
Speaker 1: they lose electrons in the process, and if you are
Speaker 1: able to control the flow of those electrons, then you've
Speaker 1: got a battery. So batteries date back possibly as long
Speaker 1: as though more than two thousand years ago. Yeah, these
Speaker 1: these clay jars found in modern day Iraq and you
Speaker 1: might might have heard of them called Bagdad batteries, where um, yeah,
Speaker 1: clay jars that contained an iron rod and cased in copper.
Speaker 1: Tests suggest that the jars were at some point filled
Speaker 1: with with with something ascetic like vinegar or wine, and
Speaker 1: modern day replicas have successfully created an electric charge. They
Speaker 1: might have been used for something like a like any
Speaker 1: anything from religious rituals and medicinal purposes to even electro plating. Right,
Speaker 1: And if you've seen if you're a big MythBusters fan,
Speaker 1: you may have seen an episode where they actually showed
Speaker 1: these They created one of these batteries and then they
Speaker 1: tried to see if they could get enough of a
Speaker 1: charge for it to be detectable. Um, so that that's
Speaker 1: an indication of that we were familiar with the fact
Speaker 1: that certain materials under certain circumstances could omit this weird energy. Now,
Speaker 1: at that time we weren't necessarily really aware of all
Speaker 1: the things that could do, but that would change as
Speaker 1: the centuries would pass. The next big date I have
Speaker 1: is quite some time later, which is and that's when
Speaker 1: Alessandro Volta count alis Andra Volta. He's only one. If
Speaker 1: there were more than one, I would count them. Oh, sorry,
Speaker 1: you're talking about a nobility rank. So count Volta created
Speaker 1: a battery by stacking alternating layers of zinc. Lawrence just
Speaker 1: checked out at this point zinc, brine, soaked cloth or paper, uh,
Speaker 1: and silver. He used these alternating layers kind of a
Speaker 1: sandwich here. And we call this a voltaic peel peel
Speaker 1: because it's French and uh and and voltaic after volta, yes,
Speaker 1: and so uh. The this this peel or pile if
Speaker 1: you prefer, because it is a pile. Oh stuff. When
Speaker 1: you put it in this this configuration, you start getting
Speaker 1: these chemical reactions that emit electrons, and you could make
Speaker 1: the stack taller and taller to get more electrons a
Speaker 1: stronger flow of current through this peel. But in order
Speaker 1: to do that you actually had to stack it up
Speaker 1: so high that eventually the weight from the top would
Speaker 1: start to squish the layers on the bottom, which would
Speaker 1: kind of make the brine soak out, and that would
Speaker 1: make it less effective, and also the metal itself would
Speaker 1: start to corrode fairly quickly. The Brian and the movement
Speaker 1: the electrons, right, it just wasn't wasn't a practical way
Speaker 1: of generating electricity, but it showed the premise and it
Speaker 1: gave scientists the idea of there's something here, and if
Speaker 1: we can figure out other ways of generating the same
Speaker 1: kind of energy, we might be able to harness it
Speaker 1: for something. Skipping ahead, I mean there there are lots
Speaker 1: of different developments in this technology. I have two specific ones.
Speaker 1: I think you have a few more. The next really
Speaker 1: effective one um was eighty six. Yeah, John Frederick Daniel,
Speaker 1: who was an English physicist. He created what we now
Speaker 1: call the Daniel cell, which was a you take a
Speaker 1: glass jar and on the bottom of the glass jar
Speaker 1: you put on in a copper plate. So copper plate
Speaker 1: in the bottom of the glass jar, and there's a
Speaker 1: wire from the copper plate that comes out of the jar.
Speaker 1: Then you or copper sulfate on top of that copper
Speaker 1: plate to about the halfway point of the jar. Then
Speaker 1: you suspend a zinc plate in the jar, and then
Speaker 1: you pour zinc sulfate solution on top of the zinc plate. Now,
Speaker 1: zinc sulfate is less dense than copper sulfate, so zinc
Speaker 1: sulfate will float on top of copper sulfate. If you've
Speaker 1: ever played with liquids of different densities that had different colors,
Speaker 1: then you know what I'm talking about. You can see
Speaker 1: that actual level of division. Yeah, it's actually it's one
Speaker 1: of my favorite things. I just think it's super cool
Speaker 1: when it When I see that, I'm easily amused, I
Speaker 1: admit it. But anyway, you also have a wire coming
Speaker 1: from the zinc plate uh and exiting the jar. So
Speaker 1: a wire attached to this would become that that zinc
Speaker 1: plate becomes the negative terminal that's where the electrons are
Speaker 1: flowing from, and the copper plate becomes the positive terminal
Speaker 1: that's where electrons are flowing too. And so if you
Speaker 1: were to connect the two wires together, it would very
Speaker 1: quickly burn out this bad but if you were to
Speaker 1: connect it to a circuit, it could actually do uh,
Speaker 1: it could or a load as we call it, it it
Speaker 1: could actually do work. So again, not terribly practical, it was.
Speaker 1: It was useful for anything that was stationary. But you know,
Speaker 1: you're talking about a liquid uh battery here, so it's
Speaker 1: not something that you could easily carry around or put
Speaker 1: into portable electronics, right right, Yeah, and there's there's a
Speaker 1: lot of a lot more elegant ways of getting that
Speaker 1: that electrol kind of solution of of you know, just
Speaker 1: just a charged molecule then yeah, yeah, And it wouldn't
Speaker 1: be until we developed dry cell battery technology that we
Speaker 1: started to find practical ways of using it in portable means,
Speaker 1: you know. And even then, you know, the batteries weren't
Speaker 1: small enough to use and what we consider portable electronics today,
Speaker 1: but you could move it around. Uh. The kind of
Speaker 1: Daniel cells that that John Frederick Daniel created were useful
Speaker 1: for different technologies, things like telephones. It was stuff that
Speaker 1: back then you did not carry around. I don't know
Speaker 1: if your kids know this, but telephones used to be
Speaker 1: these things that were extremely stationary. It's only recently that
Speaker 1: we started carrying them around. Uh. Anyway, that's the kind
Speaker 1: of battery that became popular for that. Uh. Now, did
Speaker 1: you have any other ones who want to talk about
Speaker 1: before we move onto the basics of batteries rechargeable batteries.
Speaker 1: The signs for that started um started with research around
Speaker 1: eighteen fifty or so when a French physicist, Gaston Plant
Speaker 1: invented the lead acid cell um and that that was
Speaker 1: a that was a precursor to to modern day car batteries.
Speaker 1: So there you have, you know, the discovery that this
Speaker 1: chemical reaction that takes place within a battery, you get
Speaker 1: compounds that form out of it, and it makes the
Speaker 1: battery over time less effective. That's why batteries die. Eventually,
Speaker 1: the active elements that would create the flow of electrons
Speaker 1: end up combining with other stuff and for the purposes
Speaker 1: of an of passing a current through a circuit, they
Speaker 1: become a nert. Yeah. Yeah, something either wears out or
Speaker 1: um or maybe the the anodeor cathode could could dissolve
Speaker 1: in the solution. Right you just essentially what it means
Speaker 1: is that you run out of the stuff you need
Speaker 1: in order to make it to make this go right?
Speaker 1: And so what what was it? Plant? Believe? Yes, what
Speaker 1: Plant discovered was that for some kinds of solutions, if
Speaker 1: you were to pass electric current through the system as
Speaker 1: opposed to siphoning it off, you could reverse this process
Speaker 1: and yeah, and create a battery that can be used
Speaker 1: more than once. Right now, this does not work for
Speaker 1: all batteries, which is why you can't just throw any
Speaker 1: regular battery into a recharger and expect it to come
Speaker 1: out fine. If you did that to a to a
Speaker 1: you know, to Adris cell or something like that, mostly
Speaker 1: just explode, right. Yeah, that these are has to be
Speaker 1: batteries that are using specific uh compounds in it for
Speaker 1: it to have this this reversible reaction, because not all
Speaker 1: compounds will reverse some of them once they're done, they're
Speaker 1: done and battery. We will talk about that a little
Speaker 1: bit a little bit later. Um, but but let's let's
Speaker 1: talk about how how exactly this this circuitry works. Okay, So,
Speaker 1: if you've ever looked at a battery, you've seen that
Speaker 1: there's a side that is labeled as a plus and
Speaker 1: one that's labeled as a minus, so positive and negative.
Speaker 1: If you're looking at like a nine volt battery, then
Speaker 1: they're next to each other. If you're looking at double
Speaker 1: a's or whatever, then it's on one end and the other.
Speaker 1: So the negative end the that's where the electrons flow
Speaker 1: out of. That's the electrons flow from that end through
Speaker 1: a circuit and into the positive end. Uh. Now we
Speaker 1: know that, you know, the the opposite charges attract, So
Speaker 1: that's why the negative wants to get to the positive.
Speaker 1: And inside the the the battery itself, there is a
Speaker 1: chemical called or a compound called an electro light. Now
Speaker 1: the electro light has a very important job. It blocks
Speaker 1: those electrons from just passing from the negative side to
Speaker 1: the positive side directly. Direct That would burn burn everything out. Yeah,
Speaker 1: that you wouldn't You wouldn't be able to power anything.
Speaker 1: The battery would just you would just have a chemical
Speaker 1: reaction inside a canister and it would be dead within
Speaker 1: however long it took for those reactions. Yeah. Um. So
Speaker 1: it does allow ions to pass through, but not electrons,
Speaker 1: and that becomes important. So the negative terminal is connected
Speaker 1: to something that's called the anode. The positive terminal is
Speaker 1: connected to what we call the cathode, and these together
Speaker 1: are the electrodes of a battery. Then you've got the
Speaker 1: separator between the anode and the cathode that's presenting that's
Speaker 1: preventing those two sides from reacting to each other. And
Speaker 1: you have the electro LTE that allows the electric charge
Speaker 1: to flow between cathode and anode, allowing the ions to
Speaker 1: pass through while making sure the electrons don't. And then
Speaker 1: you have a collector, which is the part of the
Speaker 1: battery that conducts the charge to the outside of the
Speaker 1: battery and through whatever the load is, the electronic load,
Speaker 1: so the circuit um. So within that anode side, the
Speaker 1: negative side, the chemical reaction that takes place is called
Speaker 1: oxid ation. It's an oxidation reaction. This ends up releasing
Speaker 1: ions and the ions move through the electro light to
Speaker 1: combine on UH the other side, and then you've got
Speaker 1: UH the release of electrons that go through the circuitry.
Speaker 1: On the catholic side, you've got the reduction reaction. That's
Speaker 1: where the catholic material and the ions UH combined with
Speaker 1: the electrons that are coming in through the circuit that
Speaker 1: they form a new compound. And so essentially you've got
Speaker 1: the anode freeing up electrons. The cathode accepting electrons, and
Speaker 1: the electrons do work along the way. So if you
Speaker 1: were to actually connect a wire from the negative terminal
Speaker 1: to the positive terminal, you would allow that that pathway
Speaker 1: to be open and it would just start to burn
Speaker 1: up that battery pretty quickly. Don't do that. It's a
Speaker 1: waste of batteries. It's going to heat up that wire.
Speaker 1: It doesn't do anything other than kill your battery. But
Speaker 1: but that's what happens. It's so when you've got it
Speaker 1: plugged into something, whenever you turn the switch on to
Speaker 1: whatever it is, whether it's a you know, a lightsaber
Speaker 1: or a phaser. You know, I allow all kinds of
Speaker 1: science fiction toys for batteries. But whenever you turn it on,
Speaker 1: it opens up that circuit and that allows the electrons
Speaker 1: to flow through. And when you turn it off, then
Speaker 1: the one of the gates gets closed essentially, and you
Speaker 1: no longer the connection is no longer there, so the
Speaker 1: battery stops the chemical reaction. It has to have that
Speaker 1: pathway open for the chemical reaction to keep going. Now,
Speaker 1: there are several different basic types of batteries that are
Speaker 1: out there, and we're just going to cover a couple
Speaker 1: of them, and we're covering them based upon the stuff
Speaker 1: that's inside them, right, because there's a whole bunch of
Speaker 1: different substances that you can use to create these reactions.
Speaker 1: Like like we said, so yeah, so so one basic
Speaker 1: type is the is alkaline batteries. Uh, the anode and
Speaker 1: alkaline batteries tends to be zinc powder. So the anode
Speaker 1: again is that negative side that's the electrons are coming from.
Speaker 1: The cathode side has typically manganese dioxide, and the electrolyte
Speaker 1: is typically potassium hydroxide. These are the kind of batteries
Speaker 1: that you typically find in double a's, C and D batteries. Right.
Speaker 1: These are all examples of this is an example of
Speaker 1: dry cell batteries. Yes, which dry cell batteries. One of
Speaker 1: the big benefits of those that you don't have to
Speaker 1: worry about liquid slashing around inside the battery, so that
Speaker 1: allows it to be used in lots of applications. You know,
Speaker 1: anything that's liquid obviously you can't shake around too much
Speaker 1: or else just gonna disrupt it and you're not gonna
Speaker 1: have a working battery. For they're more they're more more volatile. Yeah,
Speaker 1: you want that, you want then a very h stationary position.
Speaker 1: Then you've got zinc carbon batteries. Uh. These have an
Speaker 1: anode that has that's zinc obviously. Uh. And then you've
Speaker 1: got the meganese dioxide cathode. But the electrolyte in this
Speaker 1: case is often either ammonium chloride or zinc chloride. These
Speaker 1: are often found in triple A, double A, C and
Speaker 1: D dry cell batteries. Then you've got lithium ion batteries.
Speaker 1: These are the ones that we find in laptops, smartphones, cameras,
Speaker 1: that kind of stuff. They are rechargeable batteries and they
Speaker 1: have different materials in them. But uh, one common version
Speaker 1: of lithium ion batteries uses a carbon note and a
Speaker 1: lithium cobalt oxide cathode and uh and yeah, these are
Speaker 1: the ones that we use when we're recharging our our
Speaker 1: various electronics very frequently anyway. Then you've got lead acid batteries.
Speaker 1: These are the ones that you often find in cars.
Speaker 1: These are more heavy duty, right, they are more volatile.
Speaker 1: They do include liquid, Yeah, they include their they're they're
Speaker 1: electrolyte tends to be sulfuric acid. This is one of
Speaker 1: the reasons why you want to be really careful with
Speaker 1: car batteries because the materials inside them can be very
Speaker 1: caustic and and they can damage you your stuff, your car.
Speaker 1: That's why you know you've got to be really careful
Speaker 1: with these things. Um, they tend to have uh, lead
Speaker 1: dioxide and metallic lead as their electrodes. So yeah, the
Speaker 1: rechargeable battery we've already talked about, that's the kind where
Speaker 1: if you put the electric current through the battery, you
Speaker 1: reverse this uh, this chemical reaction. Uh. It depends upon
Speaker 1: what that rechargeable battery is made from, whether how effective
Speaker 1: this this process is right, because there's some kinds of
Speaker 1: rechargeable batteries that have well they have a memory, and
Speaker 1: that memory is not a good one. The memory effect
Speaker 1: is what I'm talking about. So I don't know how
Speaker 1: many of you are familiar with this, but if you've
Speaker 1: ever heard someone say that before you recharge your device,
Speaker 1: you should make sure that it's completely that the current
Speaker 1: charges completely out. This was due to some some older
Speaker 1: types of batteries that have been mostly replaced by lithium
Speaker 1: ion batteries. Nickel cadmium is the main culprit here. So
Speaker 1: the problem that some people notice with nickel cadmium is
Speaker 1: that if you used a nickel cadmium battery for a
Speaker 1: while and then you recharged it before you had completely
Speaker 1: discharged the original charge, it wouldn't hold as much of
Speaker 1: a charge the next time. So let's say that I've
Speaker 1: got a device that has a nickel cadmium battery in
Speaker 1: it and I run it down to about left like
Speaker 1: it's it only has charge left, and I decided to
Speaker 1: recharge it. Well, now it's new maximum charge is more
Speaker 1: like eight of what it used to be because I
Speaker 1: didn't let it go. It remembers that, but it doesn't
Speaker 1: let me actually consume that power anymore. So yeah, that
Speaker 1: was a problem. Now most batteries now don't have that issue.
Speaker 1: I mean, there's still a minor memory effect in some
Speaker 1: rechargeable batteries, but it's not nearly as dramatic as it
Speaker 1: the older batteries were, right, So so yeah, so if
Speaker 1: you are using a lithium ion battery and someone tells
Speaker 1: you that thing, you can you can tell them that
Speaker 1: we told you no, No, not as big a deal.
Speaker 1: And another interesting thing about batteries is what happens if
Speaker 1: you place them in series versus in parallel. So in
Speaker 1: series it sounds kind of you know, is what it is.
Speaker 1: You've you've got them hooked up so that they are
Speaker 1: all the charges running through one and then another and
Speaker 1: then another. Yeah, in a sequence exactly. And uh, if
Speaker 1: you do that, you increase the voltage of the output. Now,
Speaker 1: if you put them in parallel, you increase the current.
Speaker 1: Now you might wonder what's the differences voltage and current
Speaker 1: if you're if you're not really familiar with electronics. I
Speaker 1: always have to look this up because I I I,
Speaker 1: I always second guess myself. But voltage measures the energy
Speaker 1: per unit charge. And you can think of that is
Speaker 1: it's how strong the electrons are pushed through a circuit.
Speaker 1: So think of it like water pressure, you know, through
Speaker 1: a hose. So the greater the water pressure, the harder
Speaker 1: that water is being pushed through the hose. That's essentially
Speaker 1: your voltage, it's you know. And then current is the
Speaker 1: rate at which electric charge passes through a circuit. Now,
Speaker 1: voltage will stay constant, the voltage output will stay constant
Speaker 1: based upon whatever kind of battery you have, or whether
Speaker 1: or not they're in series. Uh, but otherwise it's going
Speaker 1: to remain the same current, however, will vary depending upon
Speaker 1: the load you place it, uh, you place on it,
Speaker 1: so and that can like the resistance of a wire
Speaker 1: can affect what the current is. So current is variable.
Speaker 1: Voltage is not, and uh, apart from the fact that
Speaker 1: if you put them in series, you increase the voltage,
Speaker 1: but once you've done that, it does not vary. Um.
Speaker 1: All right, Well that's the basis the very basic foundation
Speaker 1: of batteries. And in the moment we're going to talk
Speaker 1: about why we haven't moved very far away from this
Speaker 1: basic explanation we just gave you. But before we do that,
Speaker 1: I'd like to take a quick moment to thank our
Speaker 1: sponsored all Right, so we're back, uh, and we've learned
Speaker 1: the basic function of a battery and how it does
Speaker 1: what it does. So what's the problem. Why haven't we
Speaker 1: made super batteries that last forever and never need to
Speaker 1: be recharged and can put out more energy than uh
Speaker 1: the generator? Yeah, well, I mean, you know, there's the
Speaker 1: first commercial dry cell batteries premiered in and they haven't
Speaker 1: really changed all that much since then. Yeah, We've we've
Speaker 1: experimented with different materials, but the actual process has remained
Speaker 1: very much the same, And there are physical limits that
Speaker 1: chemical batteries have. They can only generate so much electricity
Speaker 1: through these reactions. There have been a few permutations of
Speaker 1: different things. In addition to those nickel cadmium batteries that
Speaker 1: that have the memory effect problem that we mentioned earlier,
Speaker 1: there's there was also some some nickel metal hydride, but
Speaker 1: they had a really short shelf life. They would start
Speaker 1: degrading pretty quickly. Yeah, that's another thing about some types
Speaker 1: of batteries that lithium ion batteries have that problem as well. Um,
Speaker 1: they're they're less bad at it, but they're still not ideal. Right,
Speaker 1: the idea being that these these chemical reactions, like the
Speaker 1: longer the battery sits idle, the less juice. Yeah. And
Speaker 1: and and this doesn't have anything to do with how
Speaker 1: much you use it. It's it's from the moment that
Speaker 1: they're made. Yeah. Yeah. And also you may have heard
Speaker 1: stories about, well, if you want to keep your batteries
Speaker 1: from degrading, you should put them in the refrigerator. Don't
Speaker 1: do that. Don't do that because that actually it actually
Speaker 1: slows down the chemical processes that happen when you yeah,
Speaker 1: when you're when you're trying to use the battery, and
Speaker 1: you're going to not get as much juice as you
Speaker 1: thought you were because the chemicals themselves are too cold
Speaker 1: to have those chemical reactions happen at the correct rate.
Speaker 1: They're still going to happen, but you're gonna get a
Speaker 1: easily amount of juice out of it, right. So, so far,
Speaker 1: lithium ion batteries, especially for small uses, have have been
Speaker 1: have been pretty pretty rad um. How however, they are
Speaker 1: very sensitive to high temperatures um, you know, which is
Speaker 1: occasionally why they wind up exploding, bursting into flame. Let's
Speaker 1: let's also point out that lithium is an alkali metal,
Speaker 1: so and we'll we'll talk about a little bit. We're
Speaker 1: gonna talk about a AH, a possible future type of
Speaker 1: battery that people are working on right now, where that's
Speaker 1: really an issue. Both lithium and sodium are being considered
Speaker 1: for new types of batteries, but both of them are
Speaker 1: alkali metals. The big problem, there are several problems, but
Speaker 1: the big problem I would say with that is alkali
Speaker 1: metals belong to a class where they tend to be
Speaker 1: let's say, reactive when they come into contact with water.
Speaker 1: So if you've ever heard stories about sodium and water,
Speaker 1: or if you've ever seen anyone demonstrate what happens when
Speaker 1: sodium encounters water, uh, you know it's explosive. The same
Speaker 1: thing is true of lithium. All right, this is where
Speaker 1: we get a little chemistry. Lesson, everyone, go and get
Speaker 1: your period audic table of elements. I'll wait now. If
Speaker 1: you look at the left hand side of that table
Speaker 1: of elements, you're gonna see that down the line you're
Speaker 1: gonna have lithium and you're gonna have sodium that are
Speaker 1: both in that same line, as well as potassium and
Speaker 1: some other alkali metals. That means that those elements share
Speaker 1: common characteristics, and one of those is when water comes
Speaker 1: in contacts, sometimes things go boom. So first of all,
Speaker 1: never never ever play with these I don't if you
Speaker 1: get hold of sodium or lithium, never play with that
Speaker 1: and water. This is seriously dangerous stuff. Also, probably just
Speaker 1: just don't. I mean, because because water is in the
Speaker 1: air around us in in great enough quantities that hypothetically
Speaker 1: it can burst into flame. I know of someone I didn't.
Speaker 1: This is a friend of a friend's story, so it's
Speaker 1: possibly apocryphal. So it could be urban legend. I admit that,
Speaker 1: But I know of someone who pocketed some sodium from
Speaker 1: his chemistry class and then was walking around with it
Speaker 1: in his pocket, and his body was giving off moisture,
Speaker 1: and so he began to feel a burning sensation in
Speaker 1: his pants and immediately ran to the bathroom and pulled
Speaker 1: the sodium mountain threw it into the toilet, which then exploded. Yeah, again,
Speaker 1: could be apocryphal. This is it was a story about
Speaker 1: a high school student who went to a rival school,
Speaker 1: so it could have very well been one of those
Speaker 1: stories where ha ha, the people who go to that
Speaker 1: school are so dumb, so much more dumb than the
Speaker 1: people who go to my school, which is saying something.
Speaker 1: I'm just kidding. I love all my classmates Spartans, but anyway,
Speaker 1: you were the Spartans, I was the Spartans. Were Spartans
Speaker 1: Spartans together. This is tech stuff. So but the point,
Speaker 1: the point being that these these these elements have serious
Speaker 1: drawbacks to him. And that's one of the reasons why
Speaker 1: the another reason why battery improvement has gone so slowly,
Speaker 1: because we have to find safe ways to handle this
Speaker 1: stuff so that it doesn't come into contact with water
Speaker 1: and then just blow up. Right. Part of that in
Speaker 1: lithium ion batteries specifically, is that they have to have
Speaker 1: a very small, very simple onboard computer to to manage
Speaker 1: the way that all of the bits flow around in there,
Speaker 1: and uh and and that that makes them pretty expensive.
Speaker 1: Lithium is already pretty expensive, but it makes them even
Speaker 1: more expensive than they would already be. Now, we have
Speaker 1: seen some improvements with battery life in recent years, but
Speaker 1: a lot of that doesn't come from improvements in the batteries.
Speaker 1: It's coming in improvements in the actual electronics. We are
Speaker 1: finding more efficient ways to generate the stuff we want.
Speaker 1: So your smartphones, if you've got a smartphone recently that
Speaker 1: has a decent battery life, it may not be that
Speaker 1: the battery is so much better. It's just that the
Speaker 1: people who designed the hardware and software we're able to
Speaker 1: maximize performance while being as efficient as possible. So you're
Speaker 1: still working with the same basic amount of Yeah, but
Speaker 1: you don't need as much of it to do the
Speaker 1: stuff you are doing exactly. Speaking of that juice, though,
Speaker 1: the problem with batteries, and the reason that that that
Speaker 1: gasoline has not been ousted completely by batteries. Is that
Speaker 1: gasoline has an energy density of something like thirteen thousand
Speaker 1: watt hours per kilogram, which is which is just a
Speaker 1: measure of how much of juice it has, how much
Speaker 1: how much, how much work they can get out of
Speaker 1: a given amount of gasoline. Sure, um, the best lithium
Speaker 1: ion batteries only hold about two hundred what hours per kilogram,
Speaker 1: so with of a of a hypothetical in a perfect
Speaker 1: world situation, four hundred possible, So still vastly underpowered when
Speaker 1: you compare it to gasoline. Right now, there are some
Speaker 1: people out there, very very smart people working on batteries
Speaker 1: that would have much higher densities power densities for their
Speaker 1: batteries if they can get the batteries to work, if
Speaker 1: they can get the the components to to to play nicely,
Speaker 1: to not explore oade, and to work on larger scales,
Speaker 1: and to work after more than three charges. There are
Speaker 1: a lot of barriers that are in place, and we'll
Speaker 1: talk about some specific uh cases, but keep in mind
Speaker 1: there have been dozens, if not hundreds of different experiments
Speaker 1: and trying to improve battery technology, and most of them
Speaker 1: just have not panned out. They might have seen promising
Speaker 1: at the beginning, but when you get to a point
Speaker 1: where you're thinking, all right, how are we going to
Speaker 1: scale this up where we can actually manufacture it or
Speaker 1: create a battery large enough to do something useful, and
Speaker 1: then things start to break down. So one of the
Speaker 1: ones I wanted to talk about where these things called
Speaker 1: micro batteries, And this was something that that we received
Speaker 1: from that initial request to talk about battery improvements. And
Speaker 1: this is a story about a team of researchers from
Speaker 1: the University of Illinois uh talking about a particular type
Speaker 1: of battery that uses these very tiny electrodes and lots
Speaker 1: and lots of them, and their three dimensional electrodes, and
Speaker 1: it was almost like these electrodes are kind of intertwined together,
Speaker 1: so they're very close together, which allows the ions to
Speaker 1: pass very very quickly. It also allows electrons to flow
Speaker 1: very quickly, and the idea being that you would be
Speaker 1: able to release quite a bit of energy in a
Speaker 1: short amount of time, faster than you could with most batteries,
Speaker 1: and you could also recharge the battery way faster, right,
Speaker 1: because that thoroughput speed has a lot to do with
Speaker 1: how effective a battery is. Yeah, and in fact, according
Speaker 1: to several articles that were posted about this technology. BBC
Speaker 1: did one as well as some other outlets. The claim
Speaker 1: was that such a battery would be reached could be
Speaker 1: recharged one thousand times faster than competing technology, so you
Speaker 1: could turn your you know, plug your smartphone in. Let's
Speaker 1: say your smartphone has one of these batteries in it
Speaker 1: and you plugged it in. After a second, it's fully recharged.
Speaker 1: You don't have to leave it there for hours for
Speaker 1: it to charge, which is that's a very attractive thing.
Speaker 1: So you're thinking, well, if it can release lots of energy,
Speaker 1: and if it can be recharged in a blink of
Speaker 1: an eye, where's the problem. Well, mostly the problem comes
Speaker 1: in from the manufacturing side and the scalability as well
Speaker 1: as uh the fact that it's not the most reliable technology.
Speaker 1: Ours Technica actually ran a great article where they really
Speaker 1: looked into this and and dove deeper than a lot
Speaker 1: of the other outlets did to kind of take a
Speaker 1: look at this technology with a skeptical eye, just to
Speaker 1: make sure that it really did measure up to the hype,
Speaker 1: because we've seen this before with battery technology, right, and
Speaker 1: this isn't to say that they want the team won't
Speaker 1: figure out a way of of solving the problems that
Speaker 1: they face. But here are some of the problems. One
Speaker 1: of them is that it's really hard to manufacture these things.
Speaker 1: The way that the team was doing it, they were
Speaker 1: using this uh, this essentially gold to make these little
Speaker 1: three dimensional um electrides electrodes sort of, and then they
Speaker 1: used poly styrene uh, little little tiny poly styrene pills,
Speaker 1: essentially packing them in there, twisting the electrodes around, coding
Speaker 1: it and nickel in a well in a combination of
Speaker 1: nickel and tin and then UH nickelton alloy actually, and
Speaker 1: then coding the rest of it with manganese oxy hydroxide uh,
Speaker 1: and then melting away the poly styrene so it it's gone,
Speaker 1: then immersing the whole thing to a liquid that was
Speaker 1: heated to three degrees celsius or five degrees fahrenheit. And
Speaker 1: so it's what even the team has referred to as
Speaker 1: a boutique manufacturing approach, meaning that it's very detailed, it's painstaking,
Speaker 1: it is not automated, extremely expensive. Yeah, it's no time
Speaker 1: consuming exactly, not something that's scalable to mass manufacturing methods
Speaker 1: right now, certainly right that's not to say that they
Speaker 1: wouldn't find some other way of doing it. They may
Speaker 1: find a way of doing it where it doesn't require
Speaker 1: this series of painstaking steps in order to get the
Speaker 1: result that they want, but uh, it's not ideal. Another
Speaker 1: problem is that the electrolyte they're using is combustible, so
Speaker 1: that's always a concern. If you get it too hot,
Speaker 1: it could burst into flames. Uh um, or you know,
Speaker 1: if you were to get it close to a flame,
Speaker 1: it could catch fire. And on top of all that, uh,
Speaker 1: the battery loses about five percent of its capacity with
Speaker 1: each charge discharge cycle, so after fifteen cycles it would
Speaker 1: be down to about two thirds of its original capacity.
Speaker 1: And uh, if you were to do a full discharge
Speaker 1: full charge, it might be even worse than that. So
Speaker 1: while it would recharge very quickly, it would have a
Speaker 1: little less juice each time. And so after you recharge
Speaker 1: it twenty times, yeah, you have to buy a new battery,
Speaker 1: new battery, right, So, uh, that raises lots of problems
Speaker 1: to waste problems. For example, like even if you were
Speaker 1: to say, well, that's acceptable because I want to be
Speaker 1: able to charge my phone in the second, you can
Speaker 1: do that twenty times, and then you have to go
Speaker 1: buy a new battery. And especially when the when the
Speaker 1: technology to create it is so so detailed and expensive,
Speaker 1: and to be fair, you wouldn't even you wouldn't even
Speaker 1: go twenty times, right because each time you would have
Speaker 1: less juice and so your your phone would be less
Speaker 1: and less useful over time. So after after your phone
Speaker 1: doesn't last more than a couple of hours, you think, well,
Speaker 1: I gotta get a new battery. So that might be
Speaker 1: six or seven recharges, depending upon how hard you are
Speaker 1: on electronics. If you're me, then you'd be like, all right,
Speaker 1: recharge it, give me a new battery. So um. So
Speaker 1: that that's the downside to this micro battery technology. That's
Speaker 1: not to say again that they won't find ways around that.
Speaker 1: Engineers are brilliant at finding ways of fixing problems. But
Speaker 1: it's not going to be the revolutionary battery technology that
Speaker 1: we're all going to see in our smart on in
Speaker 1: the next few months. It'll it'll at least be a
Speaker 1: couple of years before we can see this rolled out
Speaker 1: in any way, assuming that they find a way to
Speaker 1: fix these problems. Right. One of the other ones that
Speaker 1: I wanted to talk about our lithium air batteries, and
Speaker 1: this is where we're getting into those alkali metals and
Speaker 1: the concern about how they react with water exactly. You know,
Speaker 1: they could hypothetically store up to four times as as
Speaker 1: much as as lithium ion batteries, as much power as
Speaker 1: lithium ion batteries, but they work in that um. Lithium
Speaker 1: combines with with oxygen that's trapped by a carbon surface.
Speaker 1: Carbon nanotubes are are popular right now and um and
Speaker 1: the resulting interplay of these lithium ions and electrons induces
Speaker 1: the flow of current. UM. Yeah, you get a get a.
Speaker 1: One of the by products you get out of this
Speaker 1: is lithium peroxide, which is a problem because as it accumulates,
Speaker 1: it starts to make it more difficult to recharge the battery. Right.
Speaker 1: So they they've only recently figured well, they they've had
Speaker 1: a bunch of of barriers to to making this work.
Speaker 1: That is, that is one of them they're they're starting
Speaker 1: to For a long time, they didn't understand why the
Speaker 1: electrochemical reactions were going so poorly in these things, and
Speaker 1: it wasn't until uh May thirteen that that researchers at
Speaker 1: m I T and Sandia National Labs announced that they
Speaker 1: were starting to be able to observe the reactions at
Speaker 1: all to figure out why this isn't working, and that's
Speaker 1: when they started seeing this lithium peroxide forming that was
Speaker 1: inhibiting the flow of electricity. And uh, they did discover
Speaker 1: that if the electricity were flowing, that the lithium peroxide
Speaker 1: was starting to reduce around the trouble spots. And they
Speaker 1: figured that if they could improve the electron flow of
Speaker 1: the battery overall, then they might be able to get
Speaker 1: around this problem so that recharging doesn't become an issue. Right. Uh,
Speaker 1: that that explosion thing that we mentioned earlier is still
Speaker 1: at issue because when when you're dealing with you know,
Speaker 1: these these carbon surfaces are allowing air to basically breathe
Speaker 1: into the battery, and since water happens in air, Yeah,
Speaker 1: you have to find either a way of coating the
Speaker 1: lithium inside the battery so that the water would not
Speaker 1: react with the surface of lithium, or you'd have to
Speaker 1: find a way of filtering the water out entirely, so
Speaker 1: that membrane at the top end, yeah, hydrophobic membrane, that's
Speaker 1: what we'd like to call that it's scared of water.
Speaker 1: It pushes water out, So uh yeah, it's that that's
Speaker 1: an issue. Now, there is a potential alternative to lithium
Speaker 1: air batteries called sodium air batteries that are even they
Speaker 1: are they may not be able to hold as much
Speaker 1: energy as a lithium a battery. It's a lower theoretical
Speaker 1: energy density but a higher practical energy density at the
Speaker 1: current moment exactly, so current moment. So yeah, no, it's
Speaker 1: it always happens. You can't get around it. But yeah,
Speaker 1: that's so that's a stability. But again, remember sodium is
Speaker 1: probably that alkali metal groups, so against same issues. You
Speaker 1: get that water in contact with sodium and battery goal
Speaker 1: boom instead of instead of zap zap. Right. Uh. There's
Speaker 1: there's also research being done into what's being called solid
Speaker 1: state batteries UM, which are kind of kind of the
Speaker 1: lithium ion um solution to dry cell batteries. It's it's
Speaker 1: using um thin layers of solid electrolyte instead of instead
Speaker 1: of the liquid that most lithium ions use. Yeah, and
Speaker 1: then there's a I read on Wired this interesting idea
Speaker 1: of spray can batteries where each of the each of
Speaker 1: the elements that you would find within a battery, the cathodeiana,
Speaker 1: the electrolyte, all that is represented by a different can
Speaker 1: of uh sprayable material. So you could actually spray this
Speaker 1: material onto different surfaces and make a battery that way.
Speaker 1: And the idea being that this would allow you to
Speaker 1: create batteries in devices that would break the battery designed
Speaker 1: directly into the device, so you wouldn't have this blocky
Speaker 1: battery compartment. Now, it's not saying that these batteries would
Speaker 1: be particularly efficient or powerful compared to what we have now,
Speaker 1: just that this would give us more opportunity to explore
Speaker 1: different ways of shaping batteries so that they are part
Speaker 1: of our electronics and not just you know, again, not
Speaker 1: just some clunky thing that you have to find make room,
Speaker 1: make room for it, right, right, and and also not
Speaker 1: so heavy, um what would be terrific. That reminds me
Speaker 1: of the nanocomposite paper batteries that some people are are
Speaker 1: working on. These are these are composed of cellulose and
Speaker 1: um an aligned carbon nanotubes woven together um and and
Speaker 1: they're they're they're small, they're flat, they're flexible, they're implantable. Um,
Speaker 1: they could hypothetically be put into medical devices. Yeah, these
Speaker 1: could actually use biological fluid as ionic fluid. So it
Speaker 1: ends up turning your body's fluids into the electrolyteed needs.
Speaker 1: This is just making think of idiocracy. It's electrolyte. It's
Speaker 1: the thing that plants crave um. I was doing the
Speaker 1: hand gesture and everything for those of you are fans
Speaker 1: of that movie. Then there's also uh, you know, the
Speaker 1: Verge reported on bacteria that are able to transfer electricity,
Speaker 1: and scientists had known about this for a while, but
Speaker 1: they weren't sure about what the mechanism was, like how
Speaker 1: did it transfer electricity? And they discovered that that there
Speaker 1: were proteins on the bacteria surface that we're responsible for
Speaker 1: electron transfer. Uh. The bacteria is uh, this is this
Speaker 1: is going to be a train wreck of a pronunciation
Speaker 1: of me luck she wa nella oneidnisis. But anyway attaches
Speaker 1: to rusty iron and other materials and breaks those down
Speaker 1: and in the process of breaking down these materials, it
Speaker 1: releases electrons. So why are we interested in this? Because
Speaker 1: by studying biological organisms that can emit electricity as part
Speaker 1: of some process where it's consuming something, we might be
Speaker 1: able to create biological batteries, and these are these are
Speaker 1: a little bit more of fuel cell really than a battery.
Speaker 1: But and and to explain the difference, a fuel cell
Speaker 1: is a device that you put fuel into and then
Speaker 1: there's a chemical reaction that generates electricity, and then you
Speaker 1: refill the fuel cells. So and you know, with a battery,
Speaker 1: what you're doing is you're using an electric uh or
Speaker 1: electrochemical reaction to harness electricity, and then you either have
Speaker 1: to reverse the reaction in order to get the battery
Speaker 1: to do it again, or you have to replace the battery.
Speaker 1: Fuel cell, you just refill it with fuel. So hydrogen
Speaker 1: fuel cells are the ones that most people know about
Speaker 1: because those the ones that we've talked about for things
Speaker 1: like cars. Hydrogen fuel cells use hydrogen, which is the
Speaker 1: most plentiful element on Earth, although you have to break
Speaker 1: it up from other stuff. It doesn't it doesn't it's
Speaker 1: not so plentiful in its pure state. It's usually it's
Speaker 1: it's in water, which is very plentiful, and hydrocarbons as well,
Speaker 1: also very plentiful. But you have to separate the hydrogen outfast,
Speaker 1: which requires energy a lot of energy. But once you've
Speaker 1: got it, assuming that you've assuming that you found some
Speaker 1: sort of hydrogen mine where it's not going to take
Speaker 1: you too much energy to get it free. Um, you
Speaker 1: put hydrogen on one side of a membrane um that
Speaker 1: has a catalyst on it, usually something really expensive like platinum,
Speaker 1: and then on the other side of the membrane you've
Speaker 1: got oxygen. The membrane allows the hydrogen ions to pass through,
Speaker 1: but not hydrogen atoms. It has to lose the electrons
Speaker 1: for it to pass through. The electrons go through a
Speaker 1: circuit just like it would with a battery and combine
Speaker 1: on the other side. So the hydrogen ions passed through
Speaker 1: the membrane and that meets up with the oxygen and says, hey,
Speaker 1: you wanna you wanna go do something? I got my
Speaker 1: buddy here, my buddy here, and I would love to
Speaker 1: take you out to dinner. And so the two hydrogen
Speaker 1: take out the one oxygen to dinner. Meanwhile, the electrons
Speaker 1: come back over through the circuit and recombined, and then
Speaker 1: you get water. So the output of a hydrogen based
Speaker 1: fuel cell is water, electricity, and heat, which is why
Speaker 1: every pretty sweet deal. Yeah, I think This is why
Speaker 1: we would love to use it to fuel cars because
Speaker 1: instead of giving off all these different greenhouse Yeah, now,
Speaker 1: water vapor is technically a greenhouse gas, but it's water vapor.
Speaker 1: It's not carbon dioxide, it's not methane or anything like that.
Speaker 1: So that's why they're very attractive. But they are you know,
Speaker 1: they're similar to batteries, but there there is a difference.
Speaker 1: There is I do I do have a have a
Speaker 1: bio battery that I was just reading about research last
Speaker 1: November at m i T. Harvard and the Massachusetts Eye
Speaker 1: and Ear Infirmary. Um the okay, so, so mammals have
Speaker 1: in their inner ears chamber that's filled with ions and
Speaker 1: um uh. These these ions produce use an electrical potential
Speaker 1: which drives neural signals. And what this means is that
Speaker 1: this is the chamber in your ear that that lets
Speaker 1: the vibration of your ear drum be converted into an
Speaker 1: electrochemical signal that your brain can read and then interprets
Speaker 1: the sound and interprets a sound. Um and so but
Speaker 1: but but you've got this this inner chamber that's just
Speaker 1: hanging out with ions in it, which is a potential battery.
Speaker 1: Um and these researchers put UM put some electrodes in
Speaker 1: there along with a very low power electronic device, and
Speaker 1: UM the chamber produced enough power with these electrodes to
Speaker 1: power the device to wire wirelessly transmit data. That's pretty
Speaker 1: cool to to an external drive. Now again we're talking
Speaker 1: about you know, we're not talking about stuff that's that's
Speaker 1: advancing the power of batteries, but we are looking at
Speaker 1: brand new applications that could that are really exciting. Yeah,
Speaker 1: it's just but again, this isn't the thing that's going
Speaker 1: to make your cell phone last longer. Probably probably not.
Speaker 1: It's it's really really really low power, but it would
Speaker 1: it would mostly be great for for medical advances in
Speaker 1: um hearing aids. Yeah. So anyway, anyway, the advances we're
Speaker 1: talking about, for the most part, are again just refining
Speaker 1: the technology that we already have. It may turn out
Speaker 1: that we just have to find a different means of
Speaker 1: generating electricity that goes away from this electrochemical model entirely
Speaker 1: for us to get beyond this this bottleneck, or if
Speaker 1: one of these other like the if the lithium air
Speaker 1: or sodium ayor batteries work out, or if the micro
Speaker 1: battery works out, maybe maybe that will be that that
Speaker 1: would be a huge leap ahead, and if either of
Speaker 1: those of any of those were any any more efficient
Speaker 1: chemical combination. Right, So there, we're not saying it's impossible.
Speaker 1: We're just saying that it's been several decades and we've
Speaker 1: only seen incremental improvements. So don't be surprised if that
Speaker 1: stays the same. If it doesn't stay the same, aime,
Speaker 1: if we do have this huge leap, that's gonna be
Speaker 1: awesome for everybody, and that's what everyone wants. Just you know,
Speaker 1: be prepared to wait. Just what I'm saying, all right,
Speaker 1: So I think that was a good explanation of batteries,
Speaker 1: also what the future is and why it's kind of
Speaker 1: lagging behind at least in respect to the way processors
Speaker 1: are taking off. If you guys have any ideas for
Speaker 1: future episodes, there's a concept you really want to explained,
Speaker 1: or there's a particular gadget or computer that you think
Speaker 1: needs to be talked about, or there's a company or
Speaker 1: a person let us know, send us an email that
Speaker 1: address is tech stuff at Discovery dot com, or drop
Speaker 1: us a line on Facebook or Twitter. Are handled. There
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