Battery and Motor Sizing for Electric Tricycles

Abstract

In the electrification of bicycles, tricycles, wheelchairs, and other velocipedes, there is a need to size the battery and the motor according to the expected load. This is because oversizing these components leads to expensive, inefficient and underutilized systems whereas under sizing them makes the system unsafe due to the risk of overheating and component damage. This paper aims to address a procedural method for sizing the battery and motor for an electric tricycle. To achieve this objective, a working electric tricycle model was developed. By defining its top speed, acceleration time, and estimated mass, the required power output and rating of the motor was determined. Based on the voltage, power output and efficiency of the motor, the required battery size for the system was also determined. The battery capacity was chosen by considering the expected running time, load and acceleration time of the tricycle. In summary, the approach proposed uses the design parameters of mass, acceleration and velocity to determine the load-power requirement; since power is a function of force and velocity. The load requirement is subsequently used to size the components. Extrapolation of this method for other electric velocipedes is recommended. Keywords— Battery, E-bikes, Electrification, Motor, Power.