The Distributed Modular Li-Ion Battery System with the Intelligent Device for the Hybrid Vehicle Applications

摘要

Taiwan is the first country to implement the 2-wheelers' zero-emission mandate in the world in year 2000. Since then being assigned by Government, the Industry Technology Research Institute (ITRI) has consolidated his EV propulsion and the internal combustion engine technologies to develop a cost-effective hybrid propulsion system for the light-duty vehicle applications for use in metropolitan areas. The developed propulsion system is a full parallel hybrid electric 18kW power-train and consists of a 375cc lean burn engine and a 6kW motor with a high power Li-ion battery system. The high power Li-ion battery system is selected to fulfill the high output power and high efficiency demands. ITRI worked with the Li-Ion battery cell solution provider and design his own smart control system. It is an 88.8V system that comprised of twenty-four series connected high power Li-Ion cell, distributed battery management system with CAN function, and some protection device. The major characteristics of this battery system includes: 8.4kW power output above 50% SOC and 88.8V, 2000 cycle life for 50% to 80% charge/discharge at high environmental temperature, 20mV cell voltage measurement accuracy, balancing of all twentyfour cell, high speed information communicated by CAN. For safety in cell level, over-charge, external short circuit, nail-penetration, and water immerse has been tested with no explosion, no fire and the emitting gas is no human harmful. For module level safety, no over-charge/discharge occurred with the BMS protection. The battery system is also designed in module with six cells and one micro-controller based Battery Sense Module (BSM) and by implementing CAN technology, it is easily to expand the voltage range in twenty-two voltage step by serial and/or parallel and easily fits different vehicle packaging space. This article describes the key technical aspects and the battery performance results from the bench and the applied vehicle.