Polyvinylsulfonic acid and its salts

The tests of additives in spirally wound VRLA batteries [18] also included a proprietary AD7 additive, which was chemically described as polyvinylsulfonic acid or its salts, called polyvinylsulfonates [85,86], together with crystal carbon fibres, polyester fibres and Sn02 powder. None of the additives were found to increase the initial discharge capacities compared with the control. The AD7 additive did, however, show significantly better maintenance of capacity during cycling than the control. It was further claimed [81,82] that typical additive concentrations of about 

in either the positive paste or the negative paste or both, function as a binder and a plasticizer to improve life, capacity, and low-temperature performance. 

This review of work on additives to the positive plate shows that a variety of effects can be achieved. The choice of additives is very dependent on the intended application and corresponding battery requirements. Additives that enhance material utilization and/or reduce plate weight may be desirable for batteries in electric vehicles, where high specific energy is required. In automotive batteries. 

Clough, Proc. 13th Annual Battery Conference on Applications and Advances, Long Beach, CA, USA, 1998, p. 311. (IEEE Paper 98H8299.) 

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