What is Battery Degradation?

Battery degradation is the gradual, natural loss of an electric vehicle battery's capacity over time and use, which slowly reduces driving range. It results from factors such as age, number of charge cycles, exposure to extreme heat or cold, and frequent DC fast charging. Modern EV batteries are engineered to degrade slowly, often retaining a large share of capacity after many years, and manufacturers back them with long warranties that guarantee a minimum capacity for a set period or distance. For dealerships, understanding degradation is key when selling and appraising used EVs, since remaining capacity affects range, value, and warranty coverage. Advising customers on habits that slow degradation, such as avoiding constant fast charging and not routinely charging to 100 percent, adds value. Disclosing a used EV's battery health honestly, alongside remaining warranty, builds buyer confidence and reduces disputes over reduced range.