Tesla’s LFP battery holds its charge better, study says

This story is about EVs, not home energy upgrades, but it's worth a quick note if you or someone in your household is weighing an electric car. A new analysis of nearly 10,000 real-world battery tests in Sweden found that the same Tesla Model 3 ages very differently depending on which battery pack it has. The version with a CATL LFP (lithium iron phosphate) battery held onto 93.3% of its capacity after more than 62,000 miles, beating every nickel-based version of the car, including the pricier Panasonic packs, which fell to as low as 88.2%.

The reason comes down to chemistry. LFP batteries are cheaper and less energy-dense, but they tolerate being charged to 100% far better than nickel-based cells, which Tesla recommends keeping at 80-90% for daily use. Over tens of thousands of miles, that difference adds up, so the "budget" battery actually holds up better long-term.

This mainly matters for anyone shopping the used EV market, since two Model 3s of the same year and mileage can differ by five percentage points of battery health, and that isn't listed on the window sticker. There are now battery-health testing tools, including one from Tesla, that can check which pack a used car has and how much capacity it still holds before you buy.