Examination of the cycle life of valve regulated lead acid batteries

We have developed long-life valve regulated lead acid (VRLA) batteries for cycle use which are suitable for practical applications. At present, the method of evaluating a battery´s cycle life is to repeatedly discharge and charge the battery under the electrical discharge conditions actually demanded. Therefore, considerable time is required to obtain the evaluation results. We tried a new technique to forecast cycle life by investigating the total electrical discharge and the electrical discharge rate of batteries. As a result, we obtained the following two findings. First, using the new technique, we were able to forecast the cycle of a battery when the battery is discharged at an arbitrary electrical discharge current. Second, using the current of high-rate discharge, battery cycle life can be evaluated much faster.