Common failures of energy storage batteries in photovoltaic systems (lithium battery)

Capacity decay

 After multiple charge and discharge cycles, the capacity of lithium batteries will gradually decay. This is caused by chemical reactions inside the battery and structural changes in the electrode materials. For example, the positive electrode material of a lithium battery may collapse during long-term charge and discharge, making it difficult to embed and de-embed lithium ions, thereby reducing the battery capacity. When the battery capacity decays to a certain extent, the amount of electricity that the energy storage system can store decreases, and it cannot effectively store the excess electricity generated by the photovoltaic panels during the day, affecting the power generation efficiency of the entire system.

Battery Management System (BMS) Failure 

BMS is used to monitor and manage the battery's charge and discharge process. If the BMS fails, such as sensor damage, communication failure, etc., it may cause improper battery charge and discharge control. For example, if the BMS cannot accurately measure the battery's voltage and current, it may cause the battery to be overcharged or over-discharged, which will not only damage the battery itself, but also affect the battery's performance and service life, thereby reducing the power generation efficiency of the entire photovoltaic energy storage system.