The characterization of nickel-cadmium batteries for telecommunications applications. 2

In this paper the work relating to a number of different nickel-cadmium structures is described. These are the sintered positive, plastic bonded negative high performance plate stack, the double plate sintered positive/plastic bonded negative medium performance plate stack and the pocket plate stack. The technologies of the different structures are briefly described. In Part 1, results were presented from relevant telecom application testing for high temperature operation particularly relating to the nickel-cadmium sintered positive, plastic bonded negative technology. This work is being carried as part of a development of new products designed expressly to meet the requirement of telecom applications. This paper describes experiments which have been carried out to establish the performance of these various types of nickel cadmium plate technologies at elevated and standard temperatures to allow a cross comparison to be produced. Amongst the results given are the charge acceptance of the different nickel cadmium technologies at normal and elevated temperatures and maintenance periods at normal and elevated temporaries based on the change in floating current with temperature and with water consumption at room temperature. This is compared to testing on the effect of evaporation and the actual water consumption at elevated temperatures. In addition information is given illustrating the long lifetime of nickel cadmium batteries in sensitive applications and field trials being set up in telecommunication applications in high temperature environments are described.