What Is It With LFP For Batteries? – CleanTechnica

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A little while ago, the great CleanTechnica editor and famous man around what Steve Hanley calls the gold-plated CleanTechnica water cooler, Zach Shahan, mused, “I remember the Tesla fans trashing LFP battery chemistry! I could go on and on about how it was ridiculed and how Tesla fans claimed you could never make a good electric car with it.”

I remember that BYD e6, too. I saw it at the 2010 Detroit Auto Show. It was big and boxy, not as sexy as the Model S displayed there, and it was heavy, over 5,000 pounds. The S was heavy, too, but not quite as heavy. It was easy to dismiss Chinese cars then. But that was then. I have a great deal of admiration for BYD and some other entrepreneurs that formed the basis of China’s now successful electric vehicle infrastructure. The booths were full of entrepreneurs as I visited the Detroit Auto Show, and I got a sample of their offerings. There was a tiny car maker with a small car. They offered me a good luck charm, and smiled happily and appreciatively at my attention. At another booth, I watched a display showing a metal rod immersed in a cold liquid. They displayed how well the metal conducted heat. It was used to keep battery cell temperatures under control. At that event, electric cars were nascent, and domestic carmakers gave lip service, but little else. Electric vehicles were always ten years in the future. The show did have an electric section, and there were rides in electric vehicles at the event.

I was in the electric section, displaying a small electric coupe. We were off to the side, but once the doors were open to the public, not just companies, we were swamped with people. They were all over the little yellow car, and they wanted to get in and ride it, especially the kids.

There was a section for free rides in an EV. I did not mind riding in one, but I was an early Electric Auto Association member of the Silicon Valley chapter and I did volunteer work for them for Earth Week. I drove a Think City once for EAA’s Earth Day booth. I headed off to the Palo Alto chapter and checked out a CitiCar, a tiny, boxy two-seater that looked like a homemade car, with its flat sides and all angles. Inside, in its kit car bucket seats nearly at floor level, it was graced by sheet aluminum, and sported a kit car steering wheel. On the floor between the seats was a gigantic rheostat, a resistor with a tap on it to control the voltage and current to the motor. That was controlled by the accelerator pedal. It had a DC motor and lead-acid batteries. In truth, it was little more than a kit car, but it was fascinating, and all the people in EAA were making their own electric vehicles from lead-acid batteries. Back in the ’70s and before, that was all you could hope for.

But let’s return to the 2010 Detroit Auto Show. By then, I knew things were about to change. I got an education in what LFP was all about. I installed LFP cells in a Prius to give it battery charging capability. I worked with the West Coast distributor for Thunder Sky Winston, a manufacturer of LFP cells, making battery packs and installing BMS (battery management systems). When I first saw Thunder Sky batteries, I knew immediately that electric cars were about to become very real.

In the electric section of the show, they were playing MGMT’s “Electric Feel.” Its quirky sound and beat fit how I felt about my section of the show*. It was winter, and the bright lights and sexy models inside the show were a stark contrast to the world of gray skies, icy cold air, and patchy snow outside, with ice flows in the Saint Claire River and the border of Canada in a tunnel underneath, a short walk from Cobo Hall, the location of the Detroit Auto Show. [*Editor’s note: I absolutely love that song. I forgot all about it, but being reminded of it now, I’m sure I embedded it into an article or two several years ago. —Zach]

It is hard to believe that Detroit Auto Show in 2010 was only 14 years ago. Everything has changed since then.

I knew about Tesla, and Mitsubishi had its tiny quirky car with its strange name, i-MiEV. There were very few electric vehicles at that time. Until then, there was only lip service for electric vehicles. The GM EV1 had come and gone. Honda produced one. California was a hotbed of possibility for EVs because of its zero emission vehicle (ZEV) standard. Those cars made a stab at it, and then things folded. All they had was lead acid. Improving them to nickel metal hydroxide (NiMH) was not enough. The signature of EV battery limitations was their bulk. That required that cars be two-seaters. But by that time, I thought the EV revolution was about to happen with lithium-ion batteries.

BYD was the single largest manufacturer of LFP batteries at one time, and for a while, China was trying to catch up and figure out how to make NMC batteries, a trick LG, SK, and Samsung had figured out in Korea. That put CATL ahead as a battery manufacturer, and BYD second. Now LFP is back. It is now popular and fashionable to advertise your green credentials by making batteries that have no cobalt in them. It is true that nickel-based cells cost more because of the cathode material costs that include cobalt.

Tesla fans criticized cars like the BYD e6, yes. I thought it was too heavy, but I had no issue with the batteries. Others found fault with the batteries, but not those with experience with LFP like me, for instance. In fact, I did not at first understand what Tesla was doing with a clearly volatile, and fire-prone battery chemistry. Then I found out they were using special fire suppressant materials in their packs, and they used fusible links in series with each cell so that if a cell shorted out, it would blow the link. They also worked on their cell caps to reduce pressure in the event of outgassing. None of that could stop the greater volatility and susceptibility to thermal runaway and pack fire. It only reduced the spread speed, and gave time for occupants to exit. They armored the pack against puncture with a thick aluminum pan and gave it strong side supports. Every NMC and NCA pack will catch fire if punctured. Winston showed movies of LFP punctured by nails and bullets. Those are standard tests. There is a flame test, a bake test, and a full short test. (Don’t try this at home.)

Done right, LFP can be punctured with no fire. Tesla just went ahead and used NMC and NCA anyway, and dealt with it with clever countermeasures. As NMC went to more energy density with higher nickel content, it became even more volatile.

On top of the safety benefits, LFP has much higher cycle life, a minimum of 4,000 cycles, a stiff discharge profile, and very low internal resistance. It is a really good power source. Those of you with LFP Teslas or other vehicles, hang on to them. Their battery packs could last a lifetime.

The thing is, in 2010, LFP was low energy density.

What most do not realize, is that batteries are made from components individually sourced. The cathode, anode, separator, and electrolyte are typically made by other firms. It’s not an accident. When LFP was introduced, BASF was able to source some of the subcomponents because it had a license. 3M has a license to produce NMC components. That is how it is done. As each of those improves, performance improves. As NMC batteries improved from better cathodes and electrolytes, so too did LFP batteries. BYD was an early adopter of LFP. The company kept at it, and so did CATL. Finally, it got enough density as things improved, and they realized it needed less cooling, so it could be packed better. That tipped the scales.

Tesla may now finally be making LFP batteries, or someone else may make them in the US and supply them to Tesla. However, this would never have happened if the door was not closed to importing the cells from China. As of today, there is only one major factory being built to make LFP, and that is in Arizona, scheduled to open in 2025 or 2026.

Ford wanted a Gotion plant in Michigan to make LFP batteries, but so far Sinophobia has shut it down or slowed it. By the way, that is a Michigan nonprofit news source. Take a look and given them a donation if you want.

Now, everything has to look like it has no China connections, so it will look Korean, or whatever.

Northvolt and other battery makers have tried to start fresh. To do that, it’s like I said: You need the materials and subcomponents. You need a source of lithium hydroxide or lithium carbonate, and you need a source of graphite or refined carbon of the right characteristics, an electrolyte, and a cathode source. Those kinds of things are normally made by BASF or 3M and others. You don’t just make everything from scratch yourself. To make LFP truly domestically, and without tariffs, you need a source of all those materials outside of China. It takes time to convince suppliers you have the volume to justify their investment in manufacturing to make those. Finally, with LFP,  you need a source of its unique requirements. It requires phosphorous. It is LFP, after all — lithium iron phosphate — and the world’s largest source of phosphates is in Morocco.

For my money, LFP is great and I would not mind having an LFP vehicle like the ones Tesla used to import that were produced in China. The secret is that if you have one and it has 250 miles of range, if those cells are LFP and have a cycle life of 4,000, that pack could go nearly a million miles. Everything in the car will not last a million miles unless you put a million miles on in 5 years or something really short. The calendar life of cells is beyond 15 years in normal or cool temperatures. The electrolyte spontaneously degrades with voltage and temperature and it is a very nonlinear response. Thermal management is essential.

Next up: sodium batteries — specifically, new types that use Prussian white, derived from Prussian blue, composed of iron, carbon, and nitrogen. They slip around the cobalt requirement like LFP, but add a few more advantages. They do not need a source of highly refined and purified lithium, and they have a few more advantages beyond that. They sideslip the issue of sources of pure phosphates required by LFP. Sodium-ion batteries are starting to happen in China, installed in small EVs, and CATL opened a factory. Meanwhile, there are other companies exploring sodium batteries, and research papers are delving into low temperature operation.

Speaking of predictions, I always knew nickel-based chemistries would not be the only game in town for batteries. Anyone in the field would have known that battery chemistries would divide into applications that suited them best. The advantage of nickel-based chemistries for utility storage was temporary and they quickly shifted too LFP. This evolution of battery chemistries for specific applications will continue. It is likely that when battery chemistries are developed for aviation, they may be different from what we see for cars and stationary storage. I look forward to developments in sodium batteries. It looks like they are finally here to stay as they get used in low-cost vehicles, and as they develop, they may displace LFP as LFP gets better and shifts to car applications.

Meanwhile, the development of solid state is uncertain. This kind of back and forth shifting of applications and uncertainty about which technologies will make it to market is perfectly normal and expected in what we loosely call high tech. In those fields, any number of inventions are tried, but few succeed, even if they are viable, because if some other new tech gets there first, the chances of commercial success dim. It’s not enough to make something work. It’s not enough to make something in volume. You have to get there first, too.