Certain electric vehicles from Ford and Tesla use lithium-iron-phosphate (LFP) batteries, which require different charging habits than typical nickel-manganese-cobalt (NMC) types. Automakers recommend periodically charging these LFP batteries to full capacity to calibrate the battery management system. This practice helps maintain accuracy and longevity, despite some studies suggesting potential long-term risks.
Lithium-iron-phosphate (LFP) batteries power select models like the Ford Mustang Mach-E Select and Premium trims with the standard-range 73-kilowatt-hour pack, offering up to 260 miles of range. They also equip rear-wheel-drive versions of the Tesla Model 3 and Model Y, as well as entry-level Rivian R1S and R1T, the upcoming 2027 Chevrolet Bolt, and future Chevrolet Silverado EV variants. These batteries cost about 20% less to produce than NMC types, avoid controversial sourcing of nickel and cobalt, and offer greater durability with lower fire risk. However, they provide roughly 30% less energy density, resulting in shorter range and reduced performance in cold weather.
A key difference lies in charging recommendations. Unlike most EVs, where limiting charge to 80% or 90% preserves health, LFP batteries benefit from occasional full charges. Ford displays a message on the Mustang Mach-E screen: "Charge to 100% at least once a month to maintain battery health." The company advises: "Set the maximum charge level to 100% and charge to 100% at least once per month to maintain range accuracy." Tesla suggests setting the limit to 100% for daily use and fully charging at least once per week.
This routine calibrates the battery management system, which monitors voltage, current, temperature, and other factors. Data from Recurrent shows LFP owners charge to 90% or 100% more often, with batteries tolerating high states of charge better than NMC. Yet, a study in the Journal of Electrochemical Society warns that repeated full charges may form harmful compounds on the negative electrode, accelerating degradation over time. Real-world evidence counters this somewhat, with LFP-equipped Teslas showing minimal degradation after 100,000 miles.
Owners can identify LFP batteries via the vehicle's VIN—for Ford Mach-E, the eighth digit is 4 or 5—or through Tesla's software menus. Following manufacturer guidelines ensures optimal performance without needing deep chemistry knowledge.