Lithium Iron Phosphate (LFP) Battery Health Degrades At Full Charge, Study Finds

Lithium Iron Phosphate (LFP) Battery Health Degrades At Full Charge, Study Finds

Suvrat Kothari | Aug 25, 2024

Electric vehicles powered by lithium iron phosphate (LFP) batteries are gaining popularity worldwide. Compared to traditional nickel manganese cobalt (NMC) batteries, LFP packs are cheaper to produce, pose a lower fire risk and offer greater longevity. However, they’re less energy-dense, which is why automakers typically use LFP batteries in entry-level models like the rear-wheel-drive Tesla Model 3, the base Ford Mustang Mach-E and the Dual Standard second-gen Rivian R1S among others.

Automakers say it’s best to charge your vehicle’s LFP battery to a 100% periodically, at least once a week in case of Tesla or once a month as per Ford. This helps with pack calibration, allowing you to have a more accurate range reading on your gauge cluster every time you get behind the wheel. They also recommend doing this to preserve battery health and avoid reduced performance.

That’s the exact opposite for NMC packs—offered on most EVs like Long Range Teslas—where manufacturers suggest setting a limit of 80-90% for daily charging. Charging them to a 100% can reduce the pack’s capacity to hold energy over time. This mainly happens because battery longevity is negatively associated with heat and voltage. The higher the state of charge, the more the voltage and heat in the pack which accelerates degradation.

However, a new study published last week in the Journal Of Electrochemical Society contradicts what automakers have been saying about LFP charging patterns. The study states that repeated charging cycles at a higher state of charge can harm LFP cells over time. The study specifies how this happens on the most granular level. But kudos to YouTuber Jason Fenske of Engineering Explained for breaking it down for us...more
https://insideevs.com/news/731210/lfp-battery-health-degrades-full-charge-study-finds/