Development of high power nickel-cadmium batteries for hybrid vehicles

A new high performance, long life, low cost, nickel cadmium battery has been developed for heavy hybrid vehicles. The Saft STX 600 offers the highest power to weight and longest life available with 500 W/kg peak power, 350 W/kg at 50% state of charge, and over 600 K cycles at 2% depth of discharge. Development work was funded through a cost share grant from the FTA to the New York State Consortium. The battery was developed to provide lighter weight, smaller size, lower cost energy storage for the series hybrid propulsion system on the Consortium´s highly successful low floor demonstration bus. The battery was designed with durability to level peaks and valleys of propulsion power for 6 years on demanding New York City bus routes. Cell construction is based on Saft´s time tested aviation battery technology and weighing only 2.0 kg offers users a lightweight alternative for their HEV application needs. In this paper, we focus on the specific design criteria of this cell, elements of the development program, and characterization test results