03:46 17-07-2026

Same Mileage, Different Batteries: What to Check on a Used Tesla Model 3

A Swedish study of nearly 10,000 EVs found Tesla Model 3 batteries from CATL retain more capacity than LG or Panasonic packs at the same mileage. Here's what to check before buying used.

A Tesla Model 3 fitted with a CATL lithium iron phosphate (LFP) battery held its capacity better than three other pack variants of the same model. After more than 100,000 km, these batteries averaged 93.3% of their original capacity, while nickel-based packs from LG and Panasonic ranged from 88.2% to 91.5%.

The data comes from 9,954 EV inspections carried out in Sweden between 2022 and 2026. Retailer Carla used the AVILOO diagnostic system, which measures a battery's actual condition rather than the range estimate shown on the dashboard.

The best result among Model 3 variants came from the LFP battery supplied by CATL. The LG Chem pack, built on NMC chemistry, averaged 91.5%, while the two Panasonic NCA packs, at 77.8 and 52.4 kWh, came in at 89.8% and 88.2% respectively. The gap between the best and worst result reached roughly five percentage points.

LFP's advantage isn't only about chemistry. These cells hold up better under a high state of charge and are less dependent on the usual advice to cap charging at 80–90%. Their drawbacks are extra weight and lower energy density, which is why a nickel-based pack of the same physical size typically delivers more range.

The overall ranking was topped by the Kia e-Niro and Hyundai Kona, both fitted with 64 kWh batteries: their average condition exceeded 97%. Still, tables like this shouldn't be read as a guaranteed forecast of battery life. Vehicle age, climate, fast-charging frequency, owner habits, software limits, and possible warranty battery replacements all play a role.

For a used Tesla buyer, the battery supplier's name is only a starting point. Before paying, measure the actual usable capacity, check for cell imbalance, look for battery-management errors, and review the fast-charging history. Two cars of the same year and mileage can differ noticeably in battery condition — even if both run LFP cells.