Battery capacity is measured in amp-hours (Ah) or watt-hours (Wh). Most batteries range between 300 and 600 Wh, with a charging time of less than 6 hours. Battery lifetime varies between 18,000 and 30,000 km, usually with over 1,000 charges. Under normal use, the battery should last three to four years; however, specific values depend greatly on the manufacturer.