Lithium Cobalt Oxide
Lithium Manganese Oxide
Lithium Nickel Cobalt Aluminum Oxide
These are just a few different specific chemistries in the lithium ion family. Battery types tend to be named after the chemicals used in the cathode, which is what lithium ions flow towards when the battery is being used. The anode, where the ions of a charged battery are stored for use, has much less variety in terms of its makeup. It is generally of carbon or graphite, and because these are relatively cheap materials, there is not as much research into new options.
Why are there so many battery chemistries? Different compositions optimize difference 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 more 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.
What Is An LFP Battery?
Although adoption of LFP batteries across the US has been slow, many scientists and engineers are very excited about their spread. LFP batteries are lithium ion phosphate chemistry. They are high stable, have a long life, and tend to be more resistant to heat degradation than their nickel-cobalt based cousins. Plus, their materials are easier to find and cheaper! So what's the downside? LFP batteries are about 30% less energy dense. What this means is that an LFP battery will hold slightly less energy than an NMC or NCA battery of the same size. To get the same range in an LFP pack as you would in a NCA pack, you need around 30% more battery.
Still, LFP batteries have been making headlines since at least 2021, when Tesla announced a switch to the lithium iron packs in their standard range models. 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. 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. While these decisions from automakers may be motivated by their bottom line, there are real engineering and use considerations that make LFP batteries promising.
LFP Batteries in Tesla, Ford, and Rivians
Tesla announced in October 2021 that it was switching to LFP batteries for its standard range models, both Model 3 and Model Y. The reason it kept the cobalt batteries for the Long Range trims is because of the lower energy density of LFP configurations – in order to get performance or very long range, you need a larger LFP battery that adds weight and can reduce efficiency.
The margins that make LFP work are very thin, and it is believed that they only work in Standard Range Teslas because they are engineered with efficiency in mind. However, we will see how Ford fares with using LFP packs in their much larger, much heavier F-150s. In terms of Rivian's plans to use LFP batteries, they are also changing their cell configurations to allow for additional battery power to make up the difference.
LFP Material Sourcing and Cost
The main argument for LFP batteries often boils down to material sourcing, especially when it comes to cobalt. Cobalt is a rare earth metal that is often mined in areas known for conflict and human rights violations, such as the Democratic Republic of the Congo. Switching to LFP batteries means that battery manufacturers are not reliant on cobalt, which is important both ethically and for business continuity.
In early 2022, there was a market shortage of nickel and aluminum, both of which are exported by Russia. Even prior to the invasion of Ukraine, businesses felt the sting of relying on materials with sensitive prices and sometimes hostile suppliers. Phosphate, which replaces nickel and aluminum in LFP cells, is much easier to source and so far, reliably cheaper. This means that LFP batteries can be much cheaper than cobalt-based batteries. Ford cites the cheaper materials as a main driver for the change, since their cost savings will allow them to pass lower prices to consumers.
Price Impact on EV Batteries
Price is the main reason that companies are switching to LFP batteries. Like with Tesla and the Standard Range Model 3 and Model Y, the models getting LFP packs are often designed to be entry-level priced vehicles, meaning that the customers who want them may be less flexible about price increases due to battery costs. Unlike the target shopper for a Model X Performance, the shopper interested in the base trim may be more impacted by a several-thousand-dollar price change.
LFP and Charging
It is true that LFP batteries lack some of the energy density that their NCM cousins offer. This means that the range of a Model 3 Standard Range will depend on the battery chemistry. But, while the LFP battery offers 10 miles less in terms of EPA range, they do offer some consolation.
We all know that to keep a lithium ion battery healthy, it should not be charged to 100% every day. At Recurrent, we suggest charging to 80-85% for optimal lifetime. However, this wisdom applies to NCA and NMC chemistry. Since LFP batteries are more stable, they can be charged to 100% for daily driving.
In fact, Tesla suggests charging your LFP Model 3 to 100% at least once a week to balance voltage and recalibrate range and charge readings. You can check the battery chemistry of your Model 3 by looking at the charge settings in the app – if the options include 50% and 100%, the vehicle has an LFP pack.
In effect, charging to 100% means that the usable range for an LFP powered Model 3 is the same as its EPA range, while the usable range for an NCA Model 3 is only around 90% of that. When you do the math, the LFP battery has a longer daily range.
Longer Cycle Life
One way that scientists talk about battery life is by “cycle lifetime,” or how many times a battery can be charged and then discharged before its capacity falls below 80% of original.
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 won’t even notice any additional battery degradation on an LFP.
EV Battery Safety
Although the risk of any lithium battery catching on fire is rare, highly publicized recalls for the Bolt and Kona, along with very occasional news of EV battery fires, have raised concerns about safety. 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. While a car’s thermal management should protect from any battery getting this hot, LFP batteries do add a layer of protection.
Cold Weather Charging for LFP Batteries
LFP batteries sure sound great! However, there are some downsides to consider, most notably cold weather charging and range loss. The impact of temperature on EVs is nothing new, but some aspects are especially pronounced with LFP batteries.
Preliminary reports from LFP drivers include complaints about extremely long times for the battery to warm, severely reduced range, and slow charge times in cold weather. 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.
Lowering Operating 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. As a reminder, voltage measures how much pressure drives the electrons from one electrode to the other, and thus, how much work can be done by a circuit.
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. Look no further than Tesla’s semi, which are rumored to eventually use nickel-cobalt-aluminum based 4680 cells.
LFP Batteries Are Simply Heavier
Related to their lower energy density, LFP batteries often need to be bigger - and heavier - than their NCA or NMC cousins. This can reduce efficiency in an EV and possibly cause more wear on tires that are not heavy duty.
Will Your Next EV Have An LFP Battery?
This article is a long way of saying “maybe.” Here is a list of vehicle manufacturers that have either hinted at or promised using LFP in the future.
- VW - no new updates since initial conversations in 2021
- Ford - European Mach-e and some international F-150s will be built with LFPs in coming years and will start producing them domestically in 2026
- Hyundai - no new updates