The time or distance an electric bike battery will run between chargings is impossible to judge with much accuracy. There are too many variables: terrain, speed, rider weight, bike load (shopping, kids, luggage), and more. However, we can make a few generalizations about an e-bike’s recharge time and overall working life. These generalizations should be used for comparison purposes only.
In a friction drive motor, a small, solid wheel rotates against the side of the tire in order to drive it. The first motorcycles used the same concept, with a motor mounted above the front wheel. The problem is that the drive rubs at the side of the tire. It's inefficient, and it quickly wears the sidewall away. Tires need to be replaced every couple hundred miles. For this reason, you'll seldom see electric bikes with this type of drive anymore.
The federal Consumer Product Safety Act defines a "low speed electric bicycle" as a two or three wheeled vehicle with fully operable pedals, a top speed when powered solely by the motor under 20 mph (32 km/h) and an electric motor that produces less than 750 W (1.01 hp). The Act authorizes the Consumer Product Safety Commission to protect people who ride low-speed electric vehicles by issuing necessary safety regulations.[63] The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.