Why We're Excited about LFP Batteries for Electric Cars (2024)

Lithium Cobalt Oxide. Lithium Manganese Oxide. Lithium Nickel Cobalt Aluminum Oxide.

These are just some of the various types of batteries that fall into the lithium ion family. They are generally named after the chemicals used in the cathode, which is what lithium ions flow towards when the battery is being used.

Why are there different EV battery types?

Different EV battery compositions optimize different things, such as the life span, maximum charge speed, or how much energy a cell can hold. The specific chemistry that is used depends heavily on how it is being used.

For instance, batteries with manganese have very low internal resistance and can be charged pretty fast. However, these batteries tend to have shorter lifetimes.

For EV use, the most popular batteries are NMC (lithium nickel manganese cobalt oxide) and NCA (lithium nickel cobalt aluminum oxides), which combine metals with nickel and cobalt to make them last longer and hold the most energy. However, LFP batteries, also known as lithium iron phosphate, or LiFePO4 (Li = lithium, Fe = iron, PO4 = phosphate) are the new kid on the block.

Pros and cons of LFP

Benefits of LFP Batteries

1. The cost savings. LFP batteries are cheaper to produce, and that means more affordable EVs for a wider demographic of shoppers. NCA battery cells clock in at about $120.30 per kWh, NMC at about $112.70/kWh, and LFP as low as $98.50/kWh.
2. Longer life. LFP batteries have a longer cycle life, meaning they can be used from full to empty (or the equivalent thereof), more times than NCA or NMC batteries. This is a part of why Tesla recommends charging your LFP battery to 100% once a week, but capping charged for nickel based batteries at 80%.
3. More resistant to aging from fast charging. Although our preliminary Tesla results indicated that occasional fast charging does not have any drastic, short term effect on range, laboratory science has shown us that NCA and NMC batteries are sensitive to long term degradation from frequent high-voltage, high-heat charging. The same is not necessarily true of LFP batteries. This is because LFP batteries rely on a 3-D, crystalline structure, and can withstand high temperatures without decomposing.
4. Lower fire risk. Lithium ion battery fires are usually due to extreme heat conditions, and are triggered by something called thermal runaway, which happens when the temperature of the pack exceeds a certain limit. For LFP batteries, thermal runaway temperature is at 270 degrees C, as compared to 210 C for NMC and 150 C for NCA. This makes them super safe for on-the-road uses.
5. Fewer environmental and ethical issues. Because they avoid cobalt and nickel, LFPbatteries can be produce, on average, 15-25% lower carbon emissions than NMCs. They also avoid some of the humanitarian criticisms about battery manufacturing, but not all. We have a deep dive on the topic here.

Nerdy Aside: Why do LFP batteries promise to be more resistant against heat-related aging and degradation? Simply put, the Fe-PO bond in LFP compositions is stronger than the Co-O bond in cobalt-based batteries, so that if abused (short-circuited, overheated, etc.) the oxygen atoms are much harder to remove. This means that under stress, a LFP battery is more likely to resist rapid rises in temperature, which can result in permanent battery damage or in dire cases - start a fire.

Downsides of LFPBatteries

While we’re excited about the adoption of more LFP technology, we are scientists, and we do want to mention the compromises that come with using LFP packs.

1. Lower energy density. LFP batteries give you about 30% less energy in the same sized battery. That means if you want the same range as you had in an NCA powered car, you need to add more batteries, which means more weight and hardware. For some models, this means slightly lower 0-60 acceleration, too.
2. Worse performance in sub-freezing temperatures. Reviewers and testers in Canada, Norway, and other icy climates report that range loss, even with preconditioning, can be a few percentage points above what is seen with NCA Model 3s. Warming the batteries enough to fast charge may also take longer for LFPs. This poor performance comes down to poor conductivity and slow lithium-ion diffusion. In practice, this means poor charge rate when it’s colder than −20 °C (−4 °F). NCM batteries perform significantly better, with increased capacity retention and polarization. However, it is possible that improved and more aggressive thermal management may be able to offset cold weather effects.

Which carmakers are adopting LFP batteries?

Tesla announced a switch to the lithium iron packs in their standard range models in 2021. The change started in China-made Standard Range vehicles and reached the US in 2022.

On their heels came news from Ford in 2023 that they plan to switch to LFP packs in European Mustang Mach-Es and in select F-150 markets in 2024. These new LFP packs are already on the road in Standard Range Mach-Es in the US, but in limited numbers. Recurrent only has a handful in our fleet so far. Fisker Ocean is also using LFP packs in their base configuration, the Sport.

‍Rivian announced a switch to LFP batteries and new cell configurations, allowing for faster production. They will start using LFPs in their Electric Delivery Vans for Amazon, and then switch over in their Standard Range trucks.

GM announced that its revamped Chevrolet Bolt EV would use LFP packs to help cut costs.

BMW also announced it will start using LFP batteries in 2025.

Which EV models get LFP batteries?

Tesla announced in October 2021 that it was switching to LFP batteries for its standard range models in both Model 3 and Model Y.

But why did it keep cobalt batteries for the Long Range trims?

Since the LFP packs have lower energy density, you need a larger LFP battery for long range or mind-boggling acceleration. The larger battery adds weight and can reduce efficiency. Because of this, most automakers are only looking to use them in Standard Range and non-performance trims.

However, we will see how Ford fares with using LFP packs in their much larger, much heavier F-150s.

What does Recurrent data show about LFP batteries in Teslas?

After some very public investigation this year, the world learned that the displayed dashboard range for most Teslas is higher than the actual, achievable range that the same cars actually get. Recurrent came up with a proprietary value, Real Range, to show the typical, achievable range we observe for an average Tesla. The chart below shows how much of the EPA range Teslas usually get, and the temperature dependence of this value.

What we see, at least for Tesla Model 3s, is two-fold:

1. The peak range seems to happen at a higher temperature for LFP batteries as compared to non-LFP batteries, and
2. The LFP models seem to get a higher percentage of their EPA range than the non-LFP vehicles.

Both of these results are exciting, although preliminary. They show differences in the ideal operating temperature for LFP batteries, which seem to get the highest range at around 70 degrees, compared to around 60 degrees for NCA packs.

They also show that the EPA range advertised for the Standard Range Model 3s is slightly closer to the truth than it is for the Long Range and Performance models. It’s important for Tesla drivers to know what their actual, achievable range is in the real world, in order to understand the limits and possibilities of their car. Of course, as we like to say with all things range, Your Mileage May Vary - and we’d love to hear your experience with your LFP battery!

FAQs About LFPs

Do LFP batteries last longer?

Several studies show that LFP batteries have a cycle life of 2 to 4 times longer than NMC batteries. The higher cycle life is also part of the reason that Tesla recommends charging to 100%: you may not even notice any additional battery degradation on an LFP.

Are LFP batteries safer?

LFP batteries have a much higher threshold for heat, which is what causes thermal runaway, or battery fires. For LFP batteries, thermal runaway temperature is at 270 degrees C, as compared to 210 C for NMC and 150 C for NCA.

Although it's worth reiterating that the risk of any lithium battery catching on fire is very, very rare.

Should LFP batteries be charged to 100%?

The recommendation to charge LFP batteries to 100% has nothing to do with the battery, and everything to do with the battery management system (BMS). Recurrent still suggests charging all lithium ion batteries to 80-85% for optimal life.

What we see in our data: Tesla drivers with LFP batteries in their cars charge beyond 90% far more than Tesla drivers with non-LFP batteries. Most non-LFP models are kept between 50% and 90% state of charge, while most LFP vehicles are charged between 90% and 100%.

Why this matters: LFP batteries hold up better to high states of charge, meaning that regularly charging them to 100% may not cause as much degradation as it would with a different battery chemistry.

Can LFPbatteries charge in cold weather?

Yes, LFPbatteries can certainly charge in cold conditions, but it maybe slower to charge because the car needs to spend more time warming the battery. While preconditioning does resolve these issues, drivers who can’t always anticipate their cold weather trips might suffer.

In a video from November, 2021, Bjorn Nyland shows that performance doesn’t suffer, but charging speed definitely does if you don't have time to precondition. He posits that BMS updates to the SR+ Model 3 might have improved range and thermal management in the vehicle’s second winter on the road.

Do LFP batteries hold up better to heat?

We expect LFP batteries to hold up better to the heat and heat-related degradation, but the true test will be time.We will continue to analyze the range of EVs across the country with and without LFP batteries.

What we see in our data: There is fairly even distribution across the US of LFP and non-LFP battery packs. Since the LFP packs come in the Standard Range models, which are more affordable, they are gaining popularity in a lot of metro areas.

Why this matters: While no lithium ion batteries love being stored in hot conditions, LFP batteries may hold up better to heat. If you live in a hot climate and know your car will have to be out in the sun, this may be a good consideration when you decide between trim levels.

Nerdy Aside: Why do LFP batteries promise to be more resistant against heat-related aging and degradation?

Simply put, the Fe-PO bond in LFP compositions is stronger than the Co-O bond in cobalt-based batteries, so that if abused (short-circuited, overheated, etc.) the oxygen atoms are much harder to remove. This means that under stress, a LFP battery is more likely to resist rapid rises in temperature, which can result in permanent battery damage or in dire cases - start a fire.

Are LFP batteries more ethical?

In short, yes! Switching to LFPs would reduce or eliminate the need to rely on nickel and cobalt, which are often sourced from mining operations and countries with questionable track records. A move to LFP batteries also makes it easier for American companies to participate in a domestic supply chain secure from foreign influence.

Read more about how LFP batteries help address criticism about EVs.

Do LFPs have a lower voltage?

LFP batteries have a lower operating voltage per cell than other common lithium ion batteries, which means that you might need more of them if you need a specific voltage (e.g. you want to hit a certain 0-60 time).

This means that LFP technology is not a one-size-fits-all solution. For heavy transport needs, LFP may not be as useful as cobalt-based batteries, since a higher workload may be needed.

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Will your next EV have an LFP battery?