Improving efficiency of lead acid battery electrodes, as the most widely used vehicle batteries is very important. In this research effect of addition of sodium sulfate paste to positive and negative electrodes plate s in semi-industrial scale were investigated. The SEM and XRD results from cured positive plates containing sodium sulfate additive confirms the reduction of positive size and improved particle distribution compared with positive plates without the additive. The level of active material of the plates after initial charging 4-6 % was improved. Consequently initial capacity 1.5-3.1%, time to reach to voltage of 6 volt (in cold cranking amperage test) 13-20.5% were increased. Morphology and reduction of particle size were improved which in turn increases the durability of battery. The effect of addition of the additive to ingredients of paste for positive plate is more compared when it was added to ingredient of paste for negative plate. Curing process of electrodes are both time consuming and expensive. In order to reduce the time for curing of positive electrodes using two different methods were carried out and adding lead sulfate tetrabasic and different time program. Results from addition of lead sulfate tetrabasic were not significant. Results from different time program in curing process of showed a reduction of 20 % in curing time. The efficiency of production of lead acid battery was improved. The average free lead of produced plates was 2.6 % which is below its allowed level (3 %). Key words : Positive plate, Sodium sulfate, Active material, Curing process, Tetrabasic lead sulfate, Lead percent.