Development of a rechargeable Li/SO/sub 2/ battery

Ballard Battery Systems Corporation is under contract to develop a rechargeable, ambient temperature lithium battery for USAF missile silo applications. The objective of this program is the demonstration of the technology in a hermetic cell with a capacity of at least 100 Ah. The chemistry of the system is discussed as well as the objectives and structure of the development program. This cell will ultimately be scaled-up to the 6000 Ah capacity required for the application. The short-term goal is the development, fabrication, and testing of 10 Ah, prismatic, welded cells. The chemistry selected for this program is based on the reversible Li/SO/sub 2/ system. One variation of this chemistry packaged in a C/sub s/ configuration achieved a capacity of 1.4 Ah and a cycle life of 72, 30% depth-of-discharge cycles. Initial development efforts will focus on the negative electrode with the objective of improving cycle life and safety.<>