Accumulators with better energy density than lead accumulators - using lead oxide and cadmium in sulphuric acid electrolyte

摘要

Chargeable battery has a positive PbO2 electrode, a negative Cd electrode, and an electrolyte contg. H2SO4. In the discharged state the electrolyte contains 10% H2SO4. In the discharged state the electrolyte contains 10% H2SO4 plus 5-18% cadmium ion concn., and is satd. with alkaline earth sulphates in soln. The pref. sulphates in satd. soln. are those of calcium or strontium and inactive metal frames are pref. employed for the electrodes, the frame for the Cd electrode being min. twice and pref. up to six times larger than the frame for the PbO2 electrode. A porous, electrically-inactive substance is pref. used as a diffusion barrier for the Cd ions between the PbO2 electrode and the Cd electrode. A practical PbO2/Cd accumulator which is far superior to the classical lead accumulator in terms of the power: wt. ratio. In the past, a usable PBO2/Cd battery did not exist.