Valve regulated batteries-losses of water and hydrogen through the valves and the battery containers at elevated temperatures

During accelerated testing of valve-regulated (VR) batteries there have been uncertainties about the failure modes and the accelerating factors involved. An experimental study has been performed with the batteries in an enclosed environment where the gases given off by the battery at elevated temperatures have been measured. The diffusive leakage of water and hydrogen as well as the vented gases have been measured. The results are discussed in terms of rate of dry out and corrosion. The influence of different VR-technologies is also discussed