Sodium sulphur battery development

A sodium sulfur battery utilizing a cell with a capacity of 10 Ah is described. Significant benefits have been realised by changing to the small cell concept, particularly in regard to freezer thawing of cells and safety under deliberately induced failure. At the same time the performance of the cells has been improved with a reduction in internal resistance and demonstrated long-term capacity and resistance stability. The performance of both individual cells and batteries of up to 960 cells described. The latter battery has been tested independently at the Argonne National Laboratories, confirming the excellent initial results and demonstrating its ability to be shipped without damage