F. TADAYON - Department of chemistry, north Tehran branch, Islamic azad university, Tehran
A. PARVIZKHANI - Department of chemistry, north Tehran branch, Islamic azad university, Tehran

During the last two decades, the lead–acid battery has been widely used in battery driven vehicles and for storing electrical energy from non-conventional sources. In spite of rapid improvement in its performance and design, there remain some problems of the battery, which are yet to be solved. These problems have drawn the attention of the battery scientists that has resulted in an annual publication of more than 150 papers in the scientific journals and a good number of patents [1]. The use of additives in the electrolyte is one of the approaches, which offer improvement of the battery without much alteration of other factors [2]. We use SODIUM PYROPHOSPHATE, which has been reported as a benefit additive in term of improving cycle life, decreasing self-discharge and increasing the oxygen over potential on the positive electrode and One of the reasons for reducing the capacity of lead acid battery, creating a thin layer of lead sulfate on the active surface. We make five different of concentration of SODIUM PYROPHOSPHATE and we add in battery electrolyte at the first formation and it seem that sodium pyrophosphate reduce lead sulfate on active surface of positive electrode. The effects of this additive examine by cyclic voltammetry TEST, X.R.D and initial capacity.