“We're all used to the rechargeable batteries in things like phones 'wearing out' over time. This is because all batteries lose capacity the more times they are charged and discharged, which is known as a 'cycle', including those you find in electric and hybrid vehicles. The evidence so far is that deterioration is very slow, so even after 100,000 miles and more you’ll likely still have at least 75% or more of your car’s original battery performance, if not a lot more. Some manufacturers also offer guarantees to replace the batteries if they drop below a certain level of performance within a stated period, and there are also guidelines for best practice on how to maintain your battery pack’s performance, including not letting it run down completely. Of course, if you’re buying a used electric car, it’s worth asking to view the car with a full charge so that you can easily see what its estimated maximum range is. Even so, electric cars are already proving to be more reliable - batteries and all - than far more complex combustion-engined cars.