There are several determinant factors that can help you understand how often to charge your electric bike. 1. Battery capacity. Life EV e-bikes provide 25 to 35 miles of range. More pedaling and less stress on the motor will help extend range even further. 2. Type of terrain. Riding uphill will drain your battery more to provide pedal assistance. The harder the motor has to work, the more battery power/range it will consume. 3. Weather conditions. Driving against the wind, similarly, to driving uphill will draw more current from the battery. 4. Your weight. The motor will draw more current from your battery to compensate for a heavier load. Our batteries are 36v 14.25ah. 36 represents voltage. 14.25 represents capacity. 36x14.25= 513 watt hours (total capacity). On average an e-bike uses 20WH per Mile. So 513/20WH = 25.65 Miles per charge. The 1 mile per 20WH formula takes into account average weight, minimal pedaling, weather, hills, starts and stops, etc.