Analysis of the Effect of Discharge Time on the Useful Life of Lithium-Ion Batteries in Reverse Flow Photovoltaic Systems Applications

Abstract

The increasing insertion of photovoltaic solar energy has generated some questions for energy concessionaires, mainly in relation to reverse power flow. As a result, customers are being unable to inject active power into the grid during the period of solar photovoltaic energy generation. One of the possible mitigations for this problem would be the use of battery storage systems. However, there are no clear instructions on how long it takes to discharge this energy into the grid. Using a shorter discharge time may result in a high current for a short period of time. On the other hand, a prolonged discharge time may result in a lower discharge current for a longer period of time. In this context, this work proposes an analysis of battery discharge time considering the best scenario for the useful life of the battery bank. The study shows that it is possible to increase the useful life of batteries when the discharge time is longer, extending their useful life by approximately 32 months when the discharge time increases from 3 hours to 10 hours.