Tesla's LFP Battery Holds Up Better Than Nickel-Based Versions, Study Finds

A new analysis of nearly 10,000 real-world EV battery tests has revealed a surprising trend in the performance of Tesla Model 3 batteries. The study found that the same car model holds up very differently depending on which type of battery it was built with, and the cheaper lithium iron phosphate (LFP) version comes out on top.

The analysis, conducted by Carla, a Swedish used-EV retailer, looked at data from over 9,954 battery tests conducted in Sweden between 2022 and 2026. The tests were done using AVILOO’s battery diagnostics, which measure the actual state of health rather than relying on the car’s dashboard estimate.

When broken down by battery type, the results showed a striking difference in performance. The LFP pack held its charge better than any nickel-based version of the same car, with an average battery health of 93.3% among cars that had driven more than 62,000 miles. This is a significant gap between the best and worst versions of the same car.

The data also revealed that the two nickel-cobalt-aluminum (NCA) packs from Panasonic, which Tesla previously considered its premium option, degraded the most over time. This counterintuitive result challenges the common assumption that more expensive batteries are inherently more durable.

LFP batteries have long been thought to be less durable than their more expensive counterparts due to their lower energy density and higher cost per kWh. However, this study provides a direct apples-to-apples comparison between LFP and nickel-based cells in the same car model.

The key difference between LFP and nickel-based batteries lies in their chemistry. LFP batteries are cheaper and heavier than their nickel-based counterparts but offer better thermal stability and can tolerate full 100% charging without degrading as quickly. This means that owners of Tesla Model 3s with LFP packs may benefit from improved longevity over time.

The finding aligns with previous studies, including a Tesla-funded study and multiple independent teardowns, which have consistently shown that LFP chemistry ages more gradually than nickel-based cells under high mileage conditions. It also suggests that Tesla’s decision to shift its Standard Range Model 3 and Model Y to LFP packs was not just about cost savings but may have provided an added benefit in terms of battery longevity.

The study is part of a broader analysis of the performance of various EV models, with over 20 vehicles included. The Kia e-Niro and Hyundai Kona mechanical twins topped the ranking at over 97% average battery health among cars past 62,000 miles. Every model in the top 20 averaged above 91%, indicating that many modern EVs are capable of retaining a significant portion of their original capacity even after extensive use.

The results also track with other datasets, including Geotab’s telematics study, which found average annual degradation had improved to about 1.8% per year. This suggests that EV batteries may be more durable than previously thought and could potentially last for over two decades or more under normal driving conditions.