A report is given on tests for the optimization of the lead accumulator for electric vehicles. The aim is to increase the specific energy (with adequate strength per cycle) and service life. For investigating this function systematic tests were made with different plate thicknesses and suitable plate surface. Further improvements were made by such factors, as the specific energy, which give low maintenance for the lead battery. Improved properties can be achieved by the construction and material of the casing and supports, and of the plate insulation.