Charge Equalization Systems for Serial Valve Regulated Lead-Acid (VRLA) Connected Batteries in Hybrid Power Systems Applications

摘要

An overview of the impact of equalization process on performance and behavior of Valve Regulated Lead-Acid (VRLA) batteries, which are a generally used in Hybrid Power Systems (HPS) is given in this paper. In order to extend the life time and runtime of batteries, an equalization process, with a good precision is required. Indeed, as mentioned in prior works, to achieve voltage equalization, the process must have a precision around 10 mV/cell. We have focused the impact of an unbalanced cells voltage on their lifetime. Typically, there are two equalization systems: Active equalization which is a speed process compared to a passive systems. It shows that the performance of active systems is significantly better than passive systems. Experimental results show that even for maintenance free batteries, a periodic equalization process is needed in order to extend their lifespan.