Electric car batteries lose storage capacity over time, reducing range. The amount of capacity loss depends on the type and intensity of use. Tesla has now released new data on "battery degradation" due to continuous use. According to a 2022 impact report from the U.S. electric carmaker, storage capacity decreases in the top-of-the-line Model S and Model Y after about 322,000 km on average by 12 percent, compared to 10 percent in 2021. The mid-range Model 3 and Model Y were not considered for the study, although they are sold in larger numbers with different battery chemistries. These vehicles could be used for future battery life analyses.
Tesla emphasizes that mileage is only one factor in battery capacity retention, and battery age also plays an important role. Capacity retention numbers at lower mileages likely reflect the influence of age, while higher mileage numbers, which come from vehicles with high utilization, likely reflect less influence of battery age. Tesla plans to expand disclosure on the performance of newer chemical systems once sufficient data is available.
Previously, electric car batteries were considered to wear out potentially quickly, raising concerns due to the high cost of the component. Although this has been proven false, manufacturers offer extensive warranties on the functionality and durability of their battery packs. Typically, there is 70 to 80 percent remaining capacity for the first few years and miles. Tesla offers a battery and drive unit warranty of 8 years or 240,000 kilometers for the Model S and Model X, whichever comes first. The company also guarantees to maintain at least 70 percent of battery capacity over the warranty period. For the Model 3 and Model Y with LFP (lithium iron phosphate) battery, the warranty is 8 years or 160,000 kilometers and at least 70 percent, while for the Model 3 and Model Y with nickel-lithium battery is 8 years or 192,000 kilometers and at least 70 percent.
