The EV Battery Shallow Dive: Chemistry, Safety, and Marketing BS.

[00:00:20] Hello everyone and welcome to Kilowatt, a podcast about electric vehicles, renewable energy, autonomous driving, and much, much more. My name is Bodhi and I am your host. And today we are going to talk about battery technology, innovations in battery technology, and kind of to be more specific, the BYD blade batteries. So let's jump into it. Before we start, we should identify the two most common types of battery chemistry.

[00:00:49] We have lithium iron phosphate or LFP, and then we have nickel manganese cobalt batteries or NMC. So LFP batteries are typically more robust than the NMC batteries. By robust, they suffer less battery degradation when you charge them to 100%. They tend to last a little bit longer, although all of the EV batteries right now are lasting way longer than people think about.

[00:01:19] They thought they would. They're a little bit safer, they have better thermal stability, they're cheaper. The downside is that LFP batteries are much less energy dense than the NMC batteries.

[00:01:34] The NMC batteries, on the other hand, are typically found in more expensive EVs. They are, like I said, more energy dense. They perform better in the cold. Downside is obviously they cost more, and you can't charge them to 100% as often without suffering some battery degradation. So those are the very basics when it comes to chemistry. Now we're going to talk a little bit about the components of an EV battery.

[00:02:01] So I'm going to start on the inside and work my way out. So you have the battery cell, and there's a variety of different battery cell form factors that we're going to talk about. And then those cells make up a module. And then the battery management system will monitor the cells in each individual module. And when there's a problem, then you can just replace the module. It makes it a little bit easier.

[00:02:29] And then you have the battery pack. So you have the cells that go in the modules, and the modules go into the battery pack. And that's actually called cell to module. Now, some battery packs, like Tesla's structural battery pack that they use in the Cybertruck, and they use in the Model Y, although I'm not sure if they're still using that in the Model Y. They don't really have a module, but they kind of do. Effectively, the battery pack is the module, and that is called cell to pack.

[00:02:57] And the structural battery pack, if you don't know, it's part of the structure of the car. It's not just sitting in there. It's actually adding rigidity to the vehicle, and it's a safety component. This makes the battery pack lighter and cheaper because we don't have any modules in there. So that's cell to pack, cell to module. Before we talk about the different cell form factors, the most popular cell form factors, I should say.

[00:03:26] All battery cells have some type of casein. They have an anode, they have a cathode, and they have a separator. So for the uninitiated, which I include myself in that group, the different types of battery form factors are basically based on shape or what it's made out of.

[00:03:49] So we have the cylindrical cells, which are the common battery type cell, just a common battery shape like a D cell battery. So one of the cool things about cylindrical cells is they're able to withstand the gas that builds up from the lithium ion batteries. So as these batteries age, they produce a gas, and they can withstand that buildup.

[00:04:11] And they also have vents, which prevent the gases from accumulating and causing battery swelling, which would be bad in an automobile, as you can imagine. The pros to cylindrical cells is that they're easy to manufacture, and they have good energy density. The cons, or the biggest con, I'm sure there's more pros and more cons that I'm giving you here, but the biggest con is that they're wasted space.

[00:04:35] Cylindrical cells leave gaps, and those gaps can be used for cooling, but it still leaves space there. So not a great solution if you're trying to reduce weight. And then you have pouch cells. Pouch cells are a somewhat flexible pouch-slash-envelope-shaped battery. They're able to expand and contract as the vehicle charges or discharges.

[00:05:04] They're obviously used in automobiles, but they're also used in stationary energy storage, like a whole home battery, that kind of thing, and some consumer tech. Some of the pros of pouch cells is that it's a simple design, inexpensive materials, and make it a very cheap option. They're easy to manufacture. They have good energy density, so that's good. The cons is they can be fragile, and that could be a safety risk.

[00:05:32] They don't have the rigid casing that like a cylindrical cell has. So they need to be placed inside of some very robust modules to protect them and keep them safe. And then the modules for the pouch cells, because they need to be a little more robust. They're going to be heavier than other cells, and that's going to add weight and complication than what you would find in cylindrical cells or prismatic cells.

[00:06:02] And prismatic cells, that's the next thing we're going to talk about. Prismatic cells are kind of a combination between the cylindrical cells and the pouch cells. They're rectangular shaped. They have a rigid metal exterior, like cylindrical cells, but the inside is more similar to the pouch cells, obviously minus the pouch. The pros on these prismatic cells is that because they're rectangle shaped, they fit well inside of a battery pack.

[00:06:29] This allows for minimal dead space in the battery pack, which is great. Another pro is thermal management. Obviously, we don't want battery packs to get too hot, and prismatic cells are pretty good at thermal management. Cons. Cons. The cons of a prismatic cell is that they're a bit more difficult to manufacture, the energy density isn't quite as good as the other two form factors, and it's more weight because of the thick metal cell.

[00:06:55] So that brings us to kind of the main topic of today's episode, which is blade batteries. And we're going to talk more specific about BYD's blade battery. So this particular form factor, or BYD's interpretation of it, these are long, thin cells. They're about 38 inches long. They're half an inch thick, and they're about three and a half inches tall.

[00:07:19] The way that the blade cell is designed is it allows for BYD to pack more energy density into the cell. It also removes some redundant battery components, and BYD says that they're able to increase energy density by 10%, which is great. Now, the chemistry that BYD is using, I should say, I probably should have said this at the beginning, is LFP, or the lithium iron phosphate, in these vehicles.

[00:07:48] BYD says these batteries are safer than other types of form factors. If the battery is damaged in a collision, there's theoretically less of a chance of it catching fire. One of the ways that BYD tested these cells, because there was some disbelief at their claim. So what BYD did was they did a nail penetration test.

[00:08:17] Basically, they shot a nail through the cell. And that was supposed to short out the cell and cause thermal runaway or simulate thermal runaway and catch fire. That didn't happen with the BYD battery. The temperature on the surface of the cell was between 30 and 60 degrees Celsius, which is about 80 to 140 degrees Fahrenheit. So you could pretty much touch that with your bare hand. Maybe not 140 degrees. Maybe that might be uncomfortable.

[00:08:45] But it's not going to burn all your skin off as soon as you touch it. There is some questions, though, if this test is a meaningful test or not. But BYD says these batteries are safer. So we will leave it at that. I say anything that stores energy or potential energy, like gasoline or a battery, has the potential to catch on fire. Just the way that it is.

[00:09:15] BYD says that these battery cells also help reduce cost. Because one of the things about BYD vehicles is they're really affordable. The LFP chemistry, coupled with removing those modules out that I was talking about and the other redundant components, makes these batteries pretty cheap. And BYD, and I didn't know this before I started doing this research, is the second largest battery manufacturer in the world. So that's crazy.

[00:09:40] In terms of disadvantages, the blade batteries, or BYD's blade batteries, don't do well in the cold. But LFP batteries in general don't do well in the cold. There is some high repair costs. In my notes, I said high manufacturing costs. But it's actually cheaper to manufacture. So I am wrong on that. I'm fact-checking myself as we go.

[00:10:10] But it is more expensive to repair. Because BYD uses the structural glue in the battery pack because they're structural battery packs. And it's not great because it's very hard to get the glue out so that you can get the battery cells out to repair them. So that's not a great solution. By the way, the Cybertruck uses a very similar type of structural glue when it comes to their battery packs.

[00:10:39] Sandy Munro of Munro Live and Associates or Munro Live on the YouTube. On the YouTube. I'm becoming a real old man. Anyway, Sandy Munro did a teardown of the Cybertruck battery pack. And they had a devil of a time getting those cells out. So it's definitely something that while it's easier to manufacture, repairability might not be great. All right.

[00:11:05] That's kind of the down and dirty on the battery chemistry and form factor side of things. BYD does have a second generation blade battery coming out in 2025. I would feel comfortable to say the second quarter of 2025, but we'll see. They've teased a few details about their next generation blade battery. They say higher density, which equals more range, faster charging times, 15% cost reduction.

[00:11:32] And BYD is claiming that their premium LFP batteries will compete with the NMC batteries, but for LFP prices. We'll see. They also say that the car won't catch fire, according to Reuters. And again, I don't believe that at all. So we'll see how that goes. We'll see how that goes. Anyway, I hope you learned something today. I hope it was interesting to you. And I've got one more thing for you before I let you go.

[00:12:01] And actually, I don't have it. Allison and Steve shared and put this together. They, when we were all at CES, they were actually able to get to the Zoox booth. And if you don't know who Zoox is, they are an autonomous driving service that is similar to what Elon wants to do with like the people mover, whatever he's calling it, the cyber bus or whatever. I don't remember what he calls it.

[00:12:26] But anyway, it's effectively an autonomous bus or similar to a, like a subway car. It's not your traditional vehicle. There's bench seats. And Allison's going to explain it. This isn't an interview. This is just Allison walking us. Walking is a weird term. Audibly walking us around the vehicle. So let's go ahead and listen to Allison's tour. One of the vehicles that's getting a lot of attention at CES is Zoox.

[00:12:56] And I'm standing next to it right now. This is kind of a proof of concept vehicle for allowing people to drive maybe on a route that would be considered like a small shuttle service. Not autonomous driving all over the place, but this is an autonomous vehicle. It's level four, which means it's fully automated without a driver. And this is operating in parts of San Francisco where it's on a fairly small loop. But here in Las Vegas, it's actually going out on the strip.

[00:13:22] The vehicle has an entry and exit door on both sides. It's got cameras on the, or sensors, I should say, on the top four corners. It's got LIDAR. It's got radar. It's got optical cameras and infrared. And there's four of them, which they actually overlap with each other. And this allows them to get full 360-degree view.

[00:13:45] And even if one of these got disabled in some way, the other three would still be able to give them full coverage of the road and everything around them. Now, we're looking at it from this side right now. And we can see that there's bench seating. And they're facing each other, which might be kind of weird if you're in a shuttle situation. But that's still cool. Inside, you've got what looks to be a phone display there. You can change the temperature. You can watch your maps and stuff like that.

[00:14:10] You can make contact with the driver's services through an emergency button on the top if you're nervous for some reason. There's also speakers all the way around the car above where you would think, like, the license plate would go in the front and the back. And I'm going to put my mic up against you here. Right now it's playing music. But we asked why they would have speakers on the outside. And they said so that the people inside could speak to authorities if the car was pulled over and also to speak to people that maybe are on the street. I don't know.

[00:14:39] They said, you know, what if somebody's banging on the car? Hey, quit banging on the car. So this is called Zoox Z-O-O-X. And it's kind of a proof of concept, but it's being funded by Amazon. I think Zoox is a really cool company. One of the things, because I only went to CES for really two days. I was there for three days, but I was really only there for two days. I've already talked to my wife about this, and I think she's on board. At least she was on board when we talked about it.

[00:15:09] And she's usually pretty cool about this stuff. I'm going to take an extra day so that I can see more of the show floor. Honestly, I just did not have enough time to see everything. And I would have liked to have visited the Zoox booth to see what they had going on. But a big thank you to Allison and Steve for, you know, getting the tour of the Zoox People Mover, whatever they're calling it. I don't know what they're calling it.

[00:15:34] But I would encourage you to go to Allison's website, podfeet.com, P-O-D-F-E-E-T.com, and subscribe to her mini-podcasts, which are No Silicast, Programming by Stealth, and Chit Chat Across the Bond. Plus many, many more. And Allison's contributors on a bunch of other shows. She contributes to this show. So go and support what Allison's doing. Also, I don't know if you know this or not, but Steve has a YouTube channel.

[00:16:02] And I would like to see more content from Steve. This is not me calling him out, but it is kind of me calling him out. Steve's YouTube is YouTube.com forward slash SPSheridan. And Steve's got a bunch of videos from when him and Allison went to Africa. He's got a bunch of videos up there. And they're really well done. You get a real sense of what they got to experience while they were there. So pretty cool stuff.

[00:16:31] All right, everybody. That is it for me today. If you want to email me, you can. It's Bodie, B-O-D-I-E, at 918digital.com. You can also find me on Twitter or X at 918digital. And I hope you all enjoyed this episode. And I will talk to you. I don't know when this is going out. So I'll talk to you next episode. Bye, everybody.