Lithium-ion Battery and its Management System integrated in an electric scooter

摘要

This paper describes the realization of a demonstrator by the whole team of the Laboratory for Electrical Storage (CEALSE), consisting in the realization of a lithium-ion battery pack and its Battery Management System (BMS) integrated in an electric scooter originally equipped with lead-acid batteries.rnAfter a short description of the originally lead-acid battery pack, the assembling of the new lithium-ion pack is presented, from the characterization of the A123Systems individual cells used, until the modules assembling based on a specific selection of cells in order to optimize the whole pack performances.rnThe next part is dedicated to the development of the Battery Management System of the assembled lithium-ion pack. A specific attention is dedicated to the cell-balancing method that has been developed, based on an original approach consisting in switching between two configurations of the modules, in series and in parallel respectively. Another part is dedicated to the development of a State-Of-Charge (SOC) gauge, taking into account the influence of the operating conditions on the pack remaining capacity, namely the temperature and the current profiles. Some new indicators developed by the LSE are also discussed in this section, as the State-Of-Safety (SOS) and the State-Of-Energy (SOE).rnFinally, the last part presents the results obtained from the comparison of the two packs and the two vehicles equipped respectively with these two kinds of batteries.