Electric vehicle (EV) batteries typically degrade over time, but changes in performance are more likely to signal a developing issue than a simple result of age. The high-voltage traction battery, which powers the vehicle's motor, gradually loses its ability to store energy as it ages, which can reduce driving range. However, this doesn’t necessarily mean the battery has completely failed. According to a Department of Energy analysis of around 15,000 plug-in vehicles, only 1.5 percent had battery replacements due to failure, and replacement rates stayed below 1 percent from 2016 through 2023. This suggests that complete battery failure is relatively rare in newer EVs. The key question for EV owners isn’t whether their car has lost some range, but whether the changes they're noticing are part of normal battery aging or a sign of a problem that needs professional attention. A gradual loss of range is expected over time, as battery capacity naturally declines. The Department of Energy estimates that EV batteries may last 12 to 15 years in moderate climates and 8 to 12 years in extreme ones, depending on factors like battery chemistry, temperature, charging habits, and driving patterns. A 2026 Geotab study of over 22,700 EVs found an average battery degradation of 2.3 percent per year, though individual vehicles may age faster or slower. Battery state of health (SOH) is a measure of how much usable energy a battery can hold compared to when it was new. A lower SOH usually means less range, but the range shown on a dashboard isn’t a direct indicator of battery health. Factors like temperature, cabin heating and cooling, highway driving, acceleration, hills, and added weight can all affect how far an EV travels on a charge. Cold weather, for example, can cause a temporary drop in range. If your range suddenly worsens, it’s worth checking for other causes before assuming the battery is failing. A persistent decline in range under similar conditions, however, may be a sign of battery degradation. Battery warnings and sudden performance changes are stronger indicators of potential issues. A sharp and unexplained drop in range, a new limit on how much the battery can charge, or reduced vehicle performance should be investigated, especially if they come with a battery or high-voltage system warning. Automakers like Tesla have specific high-voltage battery alerts that can reduce charge levels and range when internal conditions are detected. Owner manuals often recommend scheduling service if these alerts persist. While no single dashboard symbol indicates a battery needs replacing, a qualified service center can read diagnostic codes and battery data to determine if the issue is normal aging, a repairable fault, or a need for a full battery replacement. If an EV is experiencing a battery fault or has lost enough capacity to affect normal driving, a battery health check is the next step. Some EV manufacturers offer long-term warranties for the traction battery, though coverage details vary by model. If replacement is needed outside of warranty, costs can be high—often ranging from $5,000 to $16,000—depending on the pack size, vehicle design, labor, and parts. A diagnosis may also reveal that only a smaller repair is needed instead of a full replacement. Replacing an EV battery is not a DIY task; it requires specialized tools, training, and safety precautions, so it should be handled by trained technicians. If your EV otherwise works normally, gradual range loss alone is not a reason to replace the battery. However, a persistent warning, sudden unexplained change, or a range that no longer meets your needs should prompt a battery test before making any decisions.