An investigation of battery voltage equalisation topologies for an electric vehicle

Abstract The vehicle’s battery system consists of a series connection of 2612volt lead-acid batteries. This paper details the design and construction of a battery voltage equaliser which aims to balance the charge level of each individual battery within an hour. These batteries are divided into four banks of either six or eight batteries. Four 144Wconverters are required to transfer energy between the banks and the ends of the bus. 25 24W converters transfer energy between adjacent batteries. Due to the numbers of converters involved, the size, weight, cost, manufacturability, and efficiency are the key points of the design.