Electric two-wheelers (E2Ws) are a category of vehicles in China that includes two-wheel bikes propelled by human pedaling supplemented by electrical power from a storage battery (bicycle-style E2Ws or pedelecs), and low-speed scooters propelled almost solely by electricity (scooter-style E2Ws). Besides pedelecs, most E2Ws rely exclusively on electric power, not on human pedaling. In many countries, E2Ws are allowed to operate in the bicycle lane and are considered a bicycle from a regulatory perspective (., helmets and driver’s licenses are not required). The technology of each type of E2W is similar. The main components of an E2W include a. | Light Traction Batteries J Weinert and E VanGelder University of California Davis CA USA 2009 Elsevier . All rights reserved. Introduction Electric two-wheelers E2Ws are a category of vehicles in China that includes two-wheel bikes propelled by human pedaling supplemented by electrical power from a storage battery bicycle-style E2Ws or pedelecs and low-speed scooters propelled almost solely by electricity scooter-style E2Ws . Besides pedelecs most E2Ws rely exclusively on electric power not on human pedaling. In many countries E2Ws are allowed to operate in the bicycle lane and are considered a bicycle from a regulatory perspective . helmets and driver s licenses are not required . The technology of each type of E2W is similar. The main components of an E2W include a hub motor controller and battery. Bicycle-style E2Ws typically have 36V batteries and 180-250W motors. Scooter-style E2Ws typically have larger 48 V batteries and higher-powered 350-500 W motors. Most E2Ws are regulated not to exceed 20 km h but many especially scooters can travel at speeds in excess of that limit and some are advertised to travel at 40 km h . They can vary in speed from 25 to 40 km h 1 and range of 25-50 km on a single charge which requires 6-8 h. Electric bike batteries are recharged from a standard electrical outlet and thus require no new infrastructure. The majority of E2W users recharge them at home during the night when electricity is cheaper. In urban areas this typically means carrying either the battery or the entire E2W into a multilevel apartment building. It is also common to see bikes being charged during the day outside ground-floor shops using standard electrical outlets. There are many different types and sizes of two-wheelers around the world. Table 1 classifies the E2Ws types most commonly used according to their key attributes and compares them with bicycles and gasoline scooters. Electric two-wheelers as an urban travel mode have both positive and negative .
