Operation of lead-acid batteries for HEV applications

Hybrid electric vehicles (HEV) are approaching commercial realization, many using advanced high power, lead-acid batteries. The HEV application is quite challenging due to the high currents going to and from the batteries. Although cycle efficiencies of thin plate lead-acid batteries are as high or better than other available power sources, the heat generated by HEV mode operation is not a trivial issue. The maintenance of a desired state of charge and cell-to-cell balance offer additional complications. These issues present the vehicle integrator with additional complexity in an already complex system. Although the application is relatively new, much information exists or is being developed to help the performance of lead-acid batteries in this difficult task of HEV operation. Operating parameters are offered to help in the transition to these and other advanced transportation systems. They consist of recommendations for discharge, charge and battery management.