WEBVTT - The Evolution of Batteries 0:00:04.000 --> 0:00:07.000 Get in touch with technology with tex Stuff from how 0:00:07.040 --> 0:00:14.080 stuff Works dot Com. Hey everyone, and welcome to tech Stuff. 0:00:14.080 --> 0:00:16.599 I'm Jovin Strickland and I'm Lauren Folkebin. Today we're going 0:00:16.680 --> 0:00:19.079 to talk about something that we've tackled in a previous 0:00:19.160 --> 0:00:21.400 episode at least Chris and I did. We're gonna talk 0:00:21.400 --> 0:00:25.759 about batteries and also why have batteries been so slow 0:00:25.880 --> 0:00:29.960 to improve over time? What what could be the future 0:00:30.000 --> 0:00:33.000 of batteries and uh and what are the implications of that. 0:00:33.080 --> 0:00:36.559 This all comes to us courtesy of a listener suggestion. 0:00:37.040 --> 0:00:40.520 David via Twitter said, could we talk about the improvements 0:00:40.520 --> 0:00:43.519 and battery technology and also why battery text seems to 0:00:43.600 --> 0:00:46.240 lag behind other technology when it comes to big leaps. 0:00:46.880 --> 0:00:50.159 It's um, that's a good question. And so you know, 0:00:50.360 --> 0:00:52.640 it's something that a lot of people have commented on 0:00:52.720 --> 0:00:55.240 the fact that you have something called Moore's law. That's 0:00:55.240 --> 0:01:00.360 that observation that in general, microprocessors get twice the number 0:01:00.400 --> 0:01:02.360 of discrete elements, or if you prefer to think of 0:01:02.400 --> 0:01:05.039 it in another way, microprocessors tend to get twice as 0:01:05.040 --> 0:01:08.920 powerful every two years or so. There. Yeah, this is 0:01:08.920 --> 0:01:12.240 not exponential growth, which I have called it in previous episodes, 0:01:12.280 --> 0:01:14.160 by the way, and people right in every time and 0:01:14.160 --> 0:01:16.120 call it take us to task on it, which is 0:01:16.160 --> 0:01:19.800 important because when we get wrong, it's a misuse of 0:01:19.840 --> 0:01:23.520 the word exponential. I'm using it's a colloquial use. But 0:01:23.600 --> 0:01:25.679 I do not want to go down that hole again 0:01:25.720 --> 0:01:28.479 because I'm like you guys, I get irritated when people 0:01:28.480 --> 0:01:30.959 misuse words too. I just wish I didn't do it 0:01:30.959 --> 0:01:34.280 as frequently myself. But anyway, it does double every two 0:01:34.400 --> 0:01:38.280 years or so, and that's a phenomenal amount of growth. 0:01:38.280 --> 0:01:42.520 We're talking about microprocessors that have billions of discrete elements 0:01:42.520 --> 0:01:44.600 on them now, and they're all down at the nanoscale. 0:01:44.800 --> 0:01:48.600 So there's this amazing amount of technology that's been poured 0:01:48.640 --> 0:01:53.760 into microprocessors, partially because Morris law exists and companies strive 0:01:53.880 --> 0:01:57.240 to to keep up with it to maintain it because 0:01:57.440 --> 0:01:59.720 Moore's law, as we know, is not a real physical law. 0:01:59.800 --> 0:02:02.560 It's more of an observation, and companies no one wants 0:02:02.600 --> 0:02:04.760 to be the company that comes up and says, yeah, 0:02:04.840 --> 0:02:06.960 we can't do that. You know, we just got bored. 0:02:07.440 --> 0:02:09.680 So it means that there's been a lot of innovation 0:02:09.720 --> 0:02:13.160 in that space. But meanwhile, on the battery front, batteries 0:02:13.200 --> 0:02:16.919 have in large part remain more or less the same 0:02:17.000 --> 0:02:21.480 for decades. I mean, we've we've seen improvements in battery life, 0:02:21.520 --> 0:02:24.840 we've seen improvements in battery efficiency, but there have been 0:02:24.840 --> 0:02:29.840 some new technologies over the past fifty years. But even so, 0:02:30.040 --> 0:02:33.120 it just hasn't it hasn't at all kept up with 0:02:33.280 --> 0:02:36.000 the microprocessors assessor side. This is also, by the way, 0:02:36.040 --> 0:02:38.839 this ties into our episodes where we talked about things 0:02:38.880 --> 0:02:42.560 like the Singularity, where we talk about how technology doesn't 0:02:42.639 --> 0:02:45.360 all progress at the same rate. So while we do 0:02:45.440 --> 0:02:49.760 see devices getting more and more sophisticated and powerful, the 0:02:49.840 --> 0:02:54.480 power supplies aren't keeping up with that trend. So it 0:02:54.560 --> 0:02:57.280 may be that the Singularity, if it is ever going 0:02:57.320 --> 0:02:59.960 to arrive, is further off than what some people think, 0:03:00.120 --> 0:03:04.720 simply because the power side of the equation is lagging behind, uh, 0:03:04.840 --> 0:03:10.839 the the technological sophistication side. So why is that. Well 0:03:10.919 --> 0:03:13.799 to understand it, we kind of have to one talk 0:03:13.840 --> 0:03:16.480 about what a battery is and to sort of look 0:03:16.520 --> 0:03:18.720 at the history of the development of batteries and talk 0:03:18.760 --> 0:03:22.400 about what exactly it does now. On a very very 0:03:22.440 --> 0:03:26.800 basic level, a battery is something that uses electro chemical 0:03:26.960 --> 0:03:31.480 reactions so that you can guide electrons through a circuit 0:03:32.160 --> 0:03:34.720 and have it do work. And that's about it. Yeah, 0:03:34.760 --> 0:03:38.400 that's that's really all a battery is. And it's because 0:03:38.440 --> 0:03:41.240 there are certain chemicals that when they have these reactions, 0:03:41.600 --> 0:03:44.240 they lose electrons in the process, and if you are 0:03:44.280 --> 0:03:47.240 able to control the flow of those electrons, then you've 0:03:47.280 --> 0:03:52.240 got a battery. So batteries date back possibly as long 0:03:52.280 --> 0:03:56.000 as though more than two thousand years ago. Yeah, these 0:03:56.040 --> 0:03:59.480 these clay jars found in modern day Iraq and you 0:03:59.560 --> 0:04:02.600 might might have heard of them called Bagdad batteries, where um, yeah, 0:04:02.600 --> 0:04:05.160 clay jars that contained an iron rod and cased in copper. 0:04:05.720 --> 0:04:08.120 Tests suggest that the jars were at some point filled 0:04:08.160 --> 0:04:11.080 with with with something ascetic like vinegar or wine, and 0:04:11.360 --> 0:04:14.480 modern day replicas have successfully created an electric charge. They 0:04:14.520 --> 0:04:16.400 might have been used for something like a like any 0:04:16.440 --> 0:04:20.600 anything from religious rituals and medicinal purposes to even electro plating. Right, 0:04:20.720 --> 0:04:23.440 And if you've seen if you're a big MythBusters fan, 0:04:23.800 --> 0:04:26.120 you may have seen an episode where they actually showed 0:04:26.160 --> 0:04:28.960 these They created one of these batteries and then they 0:04:28.960 --> 0:04:30.839 tried to see if they could get enough of a 0:04:30.920 --> 0:04:34.040 charge for it to be detectable. Um, so that that's 0:04:34.040 --> 0:04:37.840 an indication of that we were familiar with the fact 0:04:37.839 --> 0:04:43.600 that certain materials under certain circumstances could omit this weird energy. Now, 0:04:43.600 --> 0:04:45.920 at that time we weren't necessarily really aware of all 0:04:45.960 --> 0:04:48.360 the things that could do, but that would change as 0:04:48.400 --> 0:04:51.760 the centuries would pass. The next big date I have 0:04:52.480 --> 0:04:57.680 is quite some time later, which is and that's when 0:04:57.720 --> 0:05:03.200 Alessandro Volta count alis Andra Volta. He's only one. If 0:05:03.200 --> 0:05:06.120 there were more than one, I would count them. Oh, sorry, 0:05:06.440 --> 0:05:10.599 you're talking about a nobility rank. So count Volta created 0:05:11.200 --> 0:05:14.880 a battery by stacking alternating layers of zinc. Lawrence just 0:05:14.960 --> 0:05:19.880 checked out at this point zinc, brine, soaked cloth or paper, uh, 0:05:19.880 --> 0:05:22.560 and silver. He used these alternating layers kind of a 0:05:22.600 --> 0:05:26.919 sandwich here. And we call this a voltaic peel peel 0:05:27.000 --> 0:05:30.960 because it's French and uh and and voltaic after volta, yes, 0:05:31.400 --> 0:05:34.920 and so uh. The this this peel or pile if 0:05:34.960 --> 0:05:38.599 you prefer, because it is a pile. Oh stuff. When 0:05:38.640 --> 0:05:41.880 you put it in this this configuration, you start getting 0:05:41.880 --> 0:05:45.719 these chemical reactions that emit electrons, and you could make 0:05:45.760 --> 0:05:48.880 the stack taller and taller to get more electrons a 0:05:49.040 --> 0:05:53.680 stronger flow of current through this peel. But in order 0:05:53.720 --> 0:05:55.640 to do that you actually had to stack it up 0:05:55.640 --> 0:05:58.360 so high that eventually the weight from the top would 0:05:58.360 --> 0:06:00.880 start to squish the layers on the bottom, which would 0:06:00.920 --> 0:06:04.600 kind of make the brine soak out, and that would 0:06:04.640 --> 0:06:08.000 make it less effective, and also the metal itself would 0:06:08.000 --> 0:06:11.400 start to corrode fairly quickly. The Brian and the movement 0:06:11.960 --> 0:06:15.440 the electrons, right, it just wasn't wasn't a practical way 0:06:15.560 --> 0:06:19.159 of generating electricity, but it showed the premise and it 0:06:19.240 --> 0:06:22.720 gave scientists the idea of there's something here, and if 0:06:22.720 --> 0:06:25.200 we can figure out other ways of generating the same 0:06:25.279 --> 0:06:27.240 kind of energy, we might be able to harness it 0:06:27.279 --> 0:06:30.400 for something. Skipping ahead, I mean there there are lots 0:06:30.400 --> 0:06:34.840 of different developments in this technology. I have two specific ones. 0:06:34.880 --> 0:06:37.400 I think you have a few more. The next really 0:06:37.440 --> 0:06:42.239 effective one um was eighty six. Yeah, John Frederick Daniel, 0:06:42.320 --> 0:06:45.600 who was an English physicist. He created what we now 0:06:45.680 --> 0:06:49.680 call the Daniel cell, which was a you take a 0:06:49.720 --> 0:06:52.080 glass jar and on the bottom of the glass jar 0:06:52.160 --> 0:06:54.599 you put on in a copper plate. So copper plate 0:06:54.640 --> 0:06:56.200 in the bottom of the glass jar, and there's a 0:06:56.240 --> 0:06:58.719 wire from the copper plate that comes out of the jar. 0:06:59.440 --> 0:07:03.720 Then you or copper sulfate on top of that copper 0:07:03.760 --> 0:07:07.479 plate to about the halfway point of the jar. Then 0:07:07.520 --> 0:07:11.480 you suspend a zinc plate in the jar, and then 0:07:11.480 --> 0:07:15.880 you pour zinc sulfate solution on top of the zinc plate. Now, 0:07:15.960 --> 0:07:20.320 zinc sulfate is less dense than copper sulfate, so zinc 0:07:20.360 --> 0:07:23.320 sulfate will float on top of copper sulfate. If you've 0:07:23.320 --> 0:07:26.320 ever played with liquids of different densities that had different colors, 0:07:26.560 --> 0:07:28.320 then you know what I'm talking about. You can see 0:07:28.360 --> 0:07:31.600 that actual level of division. Yeah, it's actually it's one 0:07:31.600 --> 0:07:33.240 of my favorite things. I just think it's super cool 0:07:33.280 --> 0:07:35.480 when it When I see that, I'm easily amused, I 0:07:35.520 --> 0:07:39.239 admit it. But anyway, you also have a wire coming 0:07:39.320 --> 0:07:43.560 from the zinc plate uh and exiting the jar. So 0:07:43.680 --> 0:07:46.440 a wire attached to this would become that that zinc 0:07:46.440 --> 0:07:49.280 plate becomes the negative terminal that's where the electrons are 0:07:49.280 --> 0:07:52.560 flowing from, and the copper plate becomes the positive terminal 0:07:52.640 --> 0:07:55.360 that's where electrons are flowing too. And so if you 0:07:55.400 --> 0:07:58.680 were to connect the two wires together, it would very 0:07:58.760 --> 0:08:01.440 quickly burn out this bad but if you were to 0:08:01.600 --> 0:08:04.720 connect it to a circuit, it could actually do uh, 0:08:04.760 --> 0:08:06.720 it could or a load as we call it, it it 0:08:06.800 --> 0:08:10.920 could actually do work. So again, not terribly practical, it was. 0:08:11.000 --> 0:08:15.000 It was useful for anything that was stationary. But you know, 0:08:15.040 --> 0:08:18.160 you're talking about a liquid uh battery here, so it's 0:08:18.200 --> 0:08:20.080 not something that you could easily carry around or put 0:08:20.080 --> 0:08:23.080 into portable electronics, right right, Yeah, and there's there's a 0:08:23.120 --> 0:08:26.560 lot of a lot more elegant ways of getting that 0:08:26.560 --> 0:08:29.280 that electrol kind of solution of of you know, just 0:08:29.280 --> 0:08:33.280 just a charged molecule then yeah, yeah, And it wouldn't 0:08:33.280 --> 0:08:35.960 be until we developed dry cell battery technology that we 0:08:36.040 --> 0:08:40.400 started to find practical ways of using it in portable means, 0:08:40.480 --> 0:08:42.920 you know. And even then, you know, the batteries weren't 0:08:42.960 --> 0:08:45.640 small enough to use and what we consider portable electronics today, 0:08:45.640 --> 0:08:48.440 but you could move it around. Uh. The kind of 0:08:48.520 --> 0:08:52.760 Daniel cells that that John Frederick Daniel created were useful 0:08:52.800 --> 0:08:56.800 for different technologies, things like telephones. It was stuff that 0:08:57.120 --> 0:08:59.400 back then you did not carry around. I don't know 0:08:59.440 --> 0:09:02.280 if your kids know this, but telephones used to be 0:09:02.360 --> 0:09:06.160 these things that were extremely stationary. It's only recently that 0:09:06.200 --> 0:09:10.240 we started carrying them around. Uh. Anyway, that's the kind 0:09:10.240 --> 0:09:12.880 of battery that became popular for that. Uh. Now, did 0:09:12.920 --> 0:09:14.440 you have any other ones who want to talk about 0:09:14.480 --> 0:09:18.280 before we move onto the basics of batteries rechargeable batteries. 0:09:18.520 --> 0:09:21.800 The signs for that started um started with research around 0:09:21.800 --> 0:09:25.640 eighteen fifty or so when a French physicist, Gaston Plant 0:09:26.480 --> 0:09:30.080 invented the lead acid cell um and that that was 0:09:30.120 --> 0:09:33.239 a that was a precursor to to modern day car batteries. 0:09:33.280 --> 0:09:36.480 So there you have, you know, the discovery that this 0:09:36.600 --> 0:09:39.560 chemical reaction that takes place within a battery, you get 0:09:39.600 --> 0:09:42.120 compounds that form out of it, and it makes the 0:09:42.160 --> 0:09:45.839 battery over time less effective. That's why batteries die. Eventually, 0:09:45.920 --> 0:09:49.760 the active elements that would create the flow of electrons 0:09:50.160 --> 0:09:53.440 end up combining with other stuff and for the purposes 0:09:53.520 --> 0:09:57.760 of an of passing a current through a circuit, they 0:09:57.840 --> 0:10:00.839 become a nert. Yeah. Yeah, something either wears out or 0:10:01.000 --> 0:10:05.160 um or maybe the the anodeor cathode could could dissolve 0:10:05.240 --> 0:10:08.160 in the solution. Right you just essentially what it means 0:10:08.200 --> 0:10:10.480 is that you run out of the stuff you need 0:10:10.760 --> 0:10:12.920 in order to make it to make this go right? 0:10:13.040 --> 0:10:17.760 And so what what was it? Plant? Believe? Yes, what 0:10:17.800 --> 0:10:21.640 Plant discovered was that for some kinds of solutions, if 0:10:21.679 --> 0:10:25.400 you were to pass electric current through the system as 0:10:25.440 --> 0:10:30.000 opposed to siphoning it off, you could reverse this process 0:10:30.080 --> 0:10:32.200 and yeah, and create a battery that can be used 0:10:32.240 --> 0:10:34.880 more than once. Right now, this does not work for 0:10:34.960 --> 0:10:37.840 all batteries, which is why you can't just throw any 0:10:38.120 --> 0:10:41.120 regular battery into a recharger and expect it to come 0:10:41.120 --> 0:10:44.600 out fine. If you did that to a to a 0:10:44.760 --> 0:10:47.160 you know, to Adris cell or something like that, mostly 0:10:47.280 --> 0:10:49.920 just explode, right. Yeah, that these are has to be 0:10:49.960 --> 0:10:53.320 batteries that are using specific uh compounds in it for 0:10:53.400 --> 0:10:55.840 it to have this this reversible reaction, because not all 0:10:55.880 --> 0:10:59.240 compounds will reverse some of them once they're done, they're 0:10:59.240 --> 0:11:01.440 done and battery. We will talk about that a little 0:11:01.440 --> 0:11:03.640 bit a little bit later. Um, but but let's let's 0:11:03.640 --> 0:11:07.280 talk about how how exactly this this circuitry works. Okay, So, 0:11:08.160 --> 0:11:09.960 if you've ever looked at a battery, you've seen that 0:11:10.000 --> 0:11:13.000 there's a side that is labeled as a plus and 0:11:13.080 --> 0:11:15.640 one that's labeled as a minus, so positive and negative. 0:11:16.160 --> 0:11:18.320 If you're looking at like a nine volt battery, then 0:11:18.320 --> 0:11:20.760 they're next to each other. If you're looking at double 0:11:20.840 --> 0:11:22.880 a's or whatever, then it's on one end and the other. 0:11:23.400 --> 0:11:27.480 So the negative end the that's where the electrons flow 0:11:27.600 --> 0:11:31.720 out of. That's the electrons flow from that end through 0:11:31.760 --> 0:11:35.240 a circuit and into the positive end. Uh. Now we 0:11:35.320 --> 0:11:38.920 know that, you know, the the opposite charges attract, So 0:11:38.920 --> 0:11:40.960 that's why the negative wants to get to the positive. 0:11:41.400 --> 0:11:45.800 And inside the the the battery itself, there is a 0:11:46.240 --> 0:11:49.640 chemical called or a compound called an electro light. Now 0:11:49.640 --> 0:11:52.680 the electro light has a very important job. It blocks 0:11:52.720 --> 0:11:55.240 those electrons from just passing from the negative side to 0:11:55.240 --> 0:11:59.320 the positive side directly. Direct That would burn burn everything out. Yeah, 0:11:59.320 --> 0:12:01.720 that you wouldn't You wouldn't be able to power anything. 0:12:01.760 --> 0:12:03.880 The battery would just you would just have a chemical 0:12:03.920 --> 0:12:06.760 reaction inside a canister and it would be dead within 0:12:07.200 --> 0:12:11.840 however long it took for those reactions. Yeah. Um. So 0:12:11.880 --> 0:12:15.640 it does allow ions to pass through, but not electrons, 0:12:16.160 --> 0:12:19.240 and that becomes important. So the negative terminal is connected 0:12:19.280 --> 0:12:23.320 to something that's called the anode. The positive terminal is 0:12:23.320 --> 0:12:26.560 connected to what we call the cathode, and these together 0:12:26.760 --> 0:12:30.080 are the electrodes of a battery. Then you've got the 0:12:30.080 --> 0:12:32.800 separator between the anode and the cathode that's presenting that's 0:12:32.800 --> 0:12:35.040 preventing those two sides from reacting to each other. And 0:12:35.080 --> 0:12:37.560 you have the electro LTE that allows the electric charge 0:12:37.600 --> 0:12:41.040 to flow between cathode and anode, allowing the ions to 0:12:41.040 --> 0:12:43.960 pass through while making sure the electrons don't. And then 0:12:44.000 --> 0:12:46.000 you have a collector, which is the part of the 0:12:46.000 --> 0:12:48.199 battery that conducts the charge to the outside of the 0:12:48.200 --> 0:12:51.559 battery and through whatever the load is, the electronic load, 0:12:51.880 --> 0:12:56.040 so the circuit um. So within that anode side, the 0:12:56.080 --> 0:12:59.439 negative side, the chemical reaction that takes place is called 0:12:59.480 --> 0:13:03.199 oxid ation. It's an oxidation reaction. This ends up releasing 0:13:03.320 --> 0:13:06.800 ions and the ions move through the electro light to 0:13:06.960 --> 0:13:11.240 combine on UH the other side, and then you've got 0:13:11.360 --> 0:13:15.679 UH the release of electrons that go through the circuitry. 0:13:16.040 --> 0:13:19.719 On the catholic side, you've got the reduction reaction. That's 0:13:19.720 --> 0:13:23.319 where the catholic material and the ions UH combined with 0:13:23.400 --> 0:13:27.600 the electrons that are coming in through the circuit that 0:13:27.800 --> 0:13:31.199 they form a new compound. And so essentially you've got 0:13:31.240 --> 0:13:34.440 the anode freeing up electrons. The cathode accepting electrons, and 0:13:34.440 --> 0:13:37.760 the electrons do work along the way. So if you 0:13:37.800 --> 0:13:41.480 were to actually connect a wire from the negative terminal 0:13:41.520 --> 0:13:45.360 to the positive terminal, you would allow that that pathway 0:13:45.400 --> 0:13:47.480 to be open and it would just start to burn 0:13:47.559 --> 0:13:52.720 up that battery pretty quickly. Don't do that. It's a 0:13:52.760 --> 0:13:54.920 waste of batteries. It's going to heat up that wire. 0:13:55.160 --> 0:13:58.720 It doesn't do anything other than kill your battery. But 0:13:58.720 --> 0:14:01.120 but that's what happens. It's so when you've got it 0:14:01.360 --> 0:14:04.480 plugged into something, whenever you turn the switch on to 0:14:04.559 --> 0:14:08.240 whatever it is, whether it's a you know, a lightsaber 0:14:08.559 --> 0:14:11.120 or a phaser. You know, I allow all kinds of 0:14:11.160 --> 0:14:15.200 science fiction toys for batteries. But whenever you turn it on, 0:14:15.280 --> 0:14:17.480 it opens up that circuit and that allows the electrons 0:14:17.520 --> 0:14:20.360 to flow through. And when you turn it off, then 0:14:20.680 --> 0:14:23.520 the one of the gates gets closed essentially, and you 0:14:23.640 --> 0:14:26.760 no longer the connection is no longer there, so the 0:14:26.760 --> 0:14:30.200 battery stops the chemical reaction. It has to have that 0:14:30.240 --> 0:14:33.600 pathway open for the chemical reaction to keep going. Now, 0:14:33.640 --> 0:14:37.640 there are several different basic types of batteries that are 0:14:37.680 --> 0:14:39.760 out there, and we're just going to cover a couple 0:14:39.760 --> 0:14:42.440 of them, and we're covering them based upon the stuff 0:14:42.480 --> 0:14:45.160 that's inside them, right, because there's a whole bunch of 0:14:45.200 --> 0:14:48.480 different substances that you can use to create these reactions. 0:14:48.560 --> 0:14:51.400 Like like we said, so yeah, so so one basic 0:14:51.440 --> 0:14:55.280 type is the is alkaline batteries. Uh, the anode and 0:14:55.400 --> 0:14:58.760 alkaline batteries tends to be zinc powder. So the anode 0:14:58.760 --> 0:15:01.680 again is that negative side that's the electrons are coming from. 0:15:01.760 --> 0:15:07.200 The cathode side has typically manganese dioxide, and the electrolyte 0:15:07.240 --> 0:15:10.840 is typically potassium hydroxide. These are the kind of batteries 0:15:10.840 --> 0:15:14.360 that you typically find in double a's, C and D batteries. Right. 0:15:14.400 --> 0:15:16.840 These are all examples of this is an example of 0:15:16.920 --> 0:15:20.840 dry cell batteries. Yes, which dry cell batteries. One of 0:15:20.840 --> 0:15:22.560 the big benefits of those that you don't have to 0:15:22.560 --> 0:15:25.440 worry about liquid slashing around inside the battery, so that 0:15:25.520 --> 0:15:28.520 allows it to be used in lots of applications. You know, 0:15:28.560 --> 0:15:31.960 anything that's liquid obviously you can't shake around too much 0:15:32.080 --> 0:15:34.000 or else just gonna disrupt it and you're not gonna 0:15:34.000 --> 0:15:37.520 have a working battery. For they're more they're more more volatile. Yeah, 0:15:37.600 --> 0:15:40.960 you want that, you want then a very h stationary position. 0:15:41.400 --> 0:15:44.320 Then you've got zinc carbon batteries. Uh. These have an 0:15:44.320 --> 0:15:48.000 anode that has that's zinc obviously. Uh. And then you've 0:15:48.000 --> 0:15:50.800 got the meganese dioxide cathode. But the electrolyte in this 0:15:50.840 --> 0:15:55.080 case is often either ammonium chloride or zinc chloride. These 0:15:55.120 --> 0:15:57.120 are often found in triple A, double A, C and 0:15:57.240 --> 0:16:00.680 D dry cell batteries. Then you've got lithium ion batteries. 0:16:00.680 --> 0:16:05.280 These are the ones that we find in laptops, smartphones, cameras, 0:16:05.400 --> 0:16:08.920 that kind of stuff. They are rechargeable batteries and they 0:16:09.120 --> 0:16:13.320 have different materials in them. But uh, one common version 0:16:13.360 --> 0:16:17.440 of lithium ion batteries uses a carbon note and a 0:16:17.560 --> 0:16:22.200 lithium cobalt oxide cathode and uh and yeah, these are 0:16:22.200 --> 0:16:24.560 the ones that we use when we're recharging our our 0:16:24.680 --> 0:16:29.000 various electronics very frequently anyway. Then you've got lead acid batteries. 0:16:29.000 --> 0:16:31.040 These are the ones that you often find in cars. 0:16:31.400 --> 0:16:34.720 These are more heavy duty, right, they are more volatile. 0:16:34.760 --> 0:16:39.360 They do include liquid, Yeah, they include their they're they're 0:16:39.400 --> 0:16:42.080 electrolyte tends to be sulfuric acid. This is one of 0:16:42.080 --> 0:16:43.840 the reasons why you want to be really careful with 0:16:43.920 --> 0:16:46.880 car batteries because the materials inside them can be very 0:16:46.920 --> 0:16:51.440 caustic and and they can damage you your stuff, your car. 0:16:51.560 --> 0:16:53.280 That's why you know you've got to be really careful 0:16:53.280 --> 0:16:57.200 with these things. Um, they tend to have uh, lead 0:16:57.200 --> 0:17:01.680 dioxide and metallic lead as their electrodes. So yeah, the 0:17:01.720 --> 0:17:04.639 rechargeable battery we've already talked about, that's the kind where 0:17:04.800 --> 0:17:07.520 if you put the electric current through the battery, you 0:17:07.560 --> 0:17:13.440 reverse this uh, this chemical reaction. Uh. It depends upon 0:17:13.520 --> 0:17:17.160 what that rechargeable battery is made from, whether how effective 0:17:17.200 --> 0:17:21.159 this this process is right, because there's some kinds of 0:17:21.200 --> 0:17:27.520 rechargeable batteries that have well they have a memory, and 0:17:27.600 --> 0:17:30.680 that memory is not a good one. The memory effect 0:17:30.720 --> 0:17:33.160 is what I'm talking about. So I don't know how 0:17:33.160 --> 0:17:36.120 many of you are familiar with this, but if you've 0:17:36.160 --> 0:17:39.320 ever heard someone say that before you recharge your device, 0:17:39.359 --> 0:17:43.480 you should make sure that it's completely that the current 0:17:43.560 --> 0:17:48.040 charges completely out. This was due to some some older 0:17:48.080 --> 0:17:50.680 types of batteries that have been mostly replaced by lithium 0:17:50.680 --> 0:17:56.040 ion batteries. Nickel cadmium is the main culprit here. So 0:17:56.119 --> 0:17:59.000 the problem that some people notice with nickel cadmium is 0:17:59.040 --> 0:18:01.720 that if you used a nickel cadmium battery for a 0:18:01.720 --> 0:18:04.880 while and then you recharged it before you had completely 0:18:04.920 --> 0:18:09.159 discharged the original charge, it wouldn't hold as much of 0:18:09.160 --> 0:18:12.200 a charge the next time. So let's say that I've 0:18:12.200 --> 0:18:14.960 got a device that has a nickel cadmium battery in 0:18:15.000 --> 0:18:18.600 it and I run it down to about left like 0:18:18.640 --> 0:18:20.960 it's it only has charge left, and I decided to 0:18:21.000 --> 0:18:25.200 recharge it. Well, now it's new maximum charge is more 0:18:25.320 --> 0:18:28.399 like eight of what it used to be because I 0:18:28.440 --> 0:18:32.600 didn't let it go. It remembers that, but it doesn't 0:18:32.720 --> 0:18:37.679 let me actually consume that power anymore. So yeah, that 0:18:37.840 --> 0:18:41.119 was a problem. Now most batteries now don't have that issue. 0:18:41.160 --> 0:18:44.160 I mean, there's still a minor memory effect in some 0:18:44.240 --> 0:18:47.800 rechargeable batteries, but it's not nearly as dramatic as it 0:18:48.200 --> 0:18:50.520 the older batteries were, right, So so yeah, so if 0:18:50.520 --> 0:18:52.879 you are using a lithium ion battery and someone tells 0:18:52.920 --> 0:18:55.119 you that thing, you can you can tell them that 0:18:55.200 --> 0:18:58.000 we told you no, No, not as big a deal. 0:18:58.600 --> 0:19:02.040 And another interesting thing about batteries is what happens if 0:19:02.119 --> 0:19:05.639 you place them in series versus in parallel. So in 0:19:05.720 --> 0:19:08.040 series it sounds kind of you know, is what it is. 0:19:08.080 --> 0:19:10.240 You've you've got them hooked up so that they are 0:19:10.720 --> 0:19:13.680 all the charges running through one and then another and 0:19:13.720 --> 0:19:18.360 then another. Yeah, in a sequence exactly. And uh, if 0:19:18.400 --> 0:19:22.280 you do that, you increase the voltage of the output. Now, 0:19:22.280 --> 0:19:25.280 if you put them in parallel, you increase the current. 0:19:25.880 --> 0:19:28.359 Now you might wonder what's the differences voltage and current 0:19:28.359 --> 0:19:30.639 if you're if you're not really familiar with electronics. I 0:19:30.720 --> 0:19:34.359 always have to look this up because I I I, 0:19:34.640 --> 0:19:38.760 I always second guess myself. But voltage measures the energy 0:19:38.800 --> 0:19:41.720 per unit charge. And you can think of that is 0:19:41.800 --> 0:19:45.200 it's how strong the electrons are pushed through a circuit. 0:19:45.280 --> 0:19:48.600 So think of it like water pressure, you know, through 0:19:48.640 --> 0:19:50.919 a hose. So the greater the water pressure, the harder 0:19:50.960 --> 0:19:54.119 that water is being pushed through the hose. That's essentially 0:19:54.160 --> 0:19:56.960 your voltage, it's you know. And then current is the 0:19:57.080 --> 0:20:01.080 rate at which electric charge passes through a circuit. Now, 0:20:01.320 --> 0:20:05.240 voltage will stay constant, the voltage output will stay constant 0:20:05.280 --> 0:20:07.760 based upon whatever kind of battery you have, or whether 0:20:07.840 --> 0:20:11.080 or not they're in series. Uh, but otherwise it's going 0:20:11.160 --> 0:20:15.160 to remain the same current, however, will vary depending upon 0:20:15.359 --> 0:20:18.440 the load you place it, uh, you place on it, 0:20:19.359 --> 0:20:23.040 so and that can like the resistance of a wire 0:20:23.560 --> 0:20:27.960 can affect what the current is. So current is variable. 0:20:28.080 --> 0:20:31.720 Voltage is not, and uh, apart from the fact that 0:20:31.760 --> 0:20:33.560 if you put them in series, you increase the voltage, 0:20:33.560 --> 0:20:37.600 but once you've done that, it does not vary. Um. 0:20:37.640 --> 0:20:42.120 All right, Well that's the basis the very basic foundation 0:20:42.400 --> 0:20:46.760 of batteries. And in the moment we're going to talk 0:20:46.800 --> 0:20:50.320 about why we haven't moved very far away from this 0:20:50.359 --> 0:20:53.199 basic explanation we just gave you. But before we do that, 0:20:53.280 --> 0:20:55.399 I'd like to take a quick moment to thank our 0:20:55.440 --> 0:20:59.920 sponsored all Right, so we're back, uh, and we've learned 0:21:00.240 --> 0:21:02.360 the basic function of a battery and how it does 0:21:02.400 --> 0:21:05.200 what it does. So what's the problem. Why haven't we 0:21:06.280 --> 0:21:10.600 made super batteries that last forever and never need to 0:21:10.640 --> 0:21:14.480 be recharged and can put out more energy than uh 0:21:14.840 --> 0:21:18.000 the generator? Yeah, well, I mean, you know, there's the 0:21:18.280 --> 0:21:23.360 first commercial dry cell batteries premiered in and they haven't 0:21:23.480 --> 0:21:26.200 really changed all that much since then. Yeah, We've we've 0:21:26.440 --> 0:21:31.879 experimented with different materials, but the actual process has remained 0:21:31.960 --> 0:21:34.919 very much the same, And there are physical limits that 0:21:35.040 --> 0:21:39.720 chemical batteries have. They can only generate so much electricity 0:21:39.760 --> 0:21:43.080 through these reactions. There have been a few permutations of 0:21:43.080 --> 0:21:46.080 different things. In addition to those nickel cadmium batteries that 0:21:46.080 --> 0:21:49.560 that have the memory effect problem that we mentioned earlier, 0:21:49.600 --> 0:21:52.800 there's there was also some some nickel metal hydride, but 0:21:53.040 --> 0:21:55.680 they had a really short shelf life. They would start 0:21:55.680 --> 0:21:59.359 degrading pretty quickly. Yeah, that's another thing about some types 0:21:59.400 --> 0:22:02.480 of batteries that lithium ion batteries have that problem as well. Um, 0:22:02.640 --> 0:22:06.359 they're they're less bad at it, but they're still not ideal. Right, 0:22:06.400 --> 0:22:09.280 the idea being that these these chemical reactions, like the 0:22:09.359 --> 0:22:15.920 longer the battery sits idle, the less juice. Yeah. And 0:22:15.920 --> 0:22:17.240 and and this doesn't have anything to do with how 0:22:17.320 --> 0:22:18.960 much you use it. It's it's from the moment that 0:22:19.000 --> 0:22:22.640 they're made. Yeah. Yeah. And also you may have heard 0:22:22.640 --> 0:22:26.159 stories about, well, if you want to keep your batteries 0:22:26.440 --> 0:22:29.120 from degrading, you should put them in the refrigerator. Don't 0:22:29.119 --> 0:22:31.399 do that. Don't do that because that actually it actually 0:22:31.400 --> 0:22:37.160 slows down the chemical processes that happen when you yeah, 0:22:37.160 --> 0:22:38.879 when you're when you're trying to use the battery, and 0:22:38.920 --> 0:22:41.200