A Battery Energy Storage System (BESS) is an advanced energy solution designed to store electrical energy in rechargeable batteries for later use. It plays a vital role in modern power systems by balancing electricity supply and demand, enhancing grid reliability, and supporting the integration of renewable energy sources such as solar and wind. The system consists of battery modules, power conversion systems, and energy management software that work together to efficiently charge, store, and discharge energy. BESS helps in peak load management, frequency regulation, voltage control, and provides backup power during outages. By reducing energy costs and improving power quality, it contributes to a more sustainable and resilient energy infrastructure.