electricbicycle

An electric bicycle, or e-bike, is a bicycle equipped with an electric motor and a rechargeable battery that assists the rider's propulsion. The motor, usually located in the hub or near the crank, provides power to the drivetrain when activated by pedaling or, on some models, by a handheld throttle. A control system modulates motor output based on rider input and battery state of charge. Batteries are commonly lithium-ion, with capacities expressed in watt-hours, influencing range.

E-bikes typically offer pedal assist, throttle assist, or both, and are designed to supplement energy rather than replace the rider. Most systems limit assistance to a maximum continuous power and to a top speed, after which the rider must rely on mechanical effort.

Types and regulations vary by region. In many markets, e-bikes are categorized as Class 1 (pedal-assist only, up to about 20 mph or 25 km/h), Class 2 (throttle-assisted up to 20 mph/25 km/h), and Class 3 (pedal assist up to 28 mph/45 km/h). Some jurisdictions require age limits, helmet use, or vehicle registration for higher-speed models.

Benefits include reduced vehicle emissions, improved mobility in congested areas, and expanded capability for riders with limited fitness. Drawbacks include higher purchase and maintenance costs, greater weight, and battery lifecycle concerns. Environmental impact depends on manufacturing, use, and end-of-life recycling.

History traces early motor-assisted bicycles in the late 19th century to modern Li-ion powered designs popular since the 2000s.