Mitigating the Effects of High Humidity on NiCd Batteries Used in Power Plants.

Abstract

As the proliferation of power plants have been on the rise to cater to the energy needs of a rising population so are the auxiliary systems that are required to support the operation of a power plant. One of the most important systems which are also very essential for the electrical protection is DC power, with which most of the relays and the breakers operate. Several standard voltage levels are used such as 48V, 110V, 220V etc. and most commonly used batteries are Nickel Cadmium, Lead Acid Batteries and Lithium Polymer Batteries. The NiCd batteries and Pb-Acid batteries are more suitable because of their robustness and the relative ease of maintenance; moreover most power plants normally do not have space constraints as selection criteria, for example an electric car.

Due consideration has to be given while setting up battery banks in areas with harsh conditions. This discussion contains a case study involving a NiCd battery bank located in a very humid area; the conditions resulted in ground faults in the battery banks. A number of factors contributed to the spillage of electrolyte from the cells and lead to the ground faults. The leakage currents caused severe damage to some of the cells, reduced their capacities drastically. A point to reckon is that, there was no structural damage or crevices in the bodies of the cells; the spillage was entirely from the gas vents on top of the cells.