The Growatt ARK LIFEPO4 battery system comes with a modular design, extra batteries can be stacked to expand your battery bank. Each Growatt ARK battery has a capacity of 2.56kWh and a maximum charge current of 25A. Operating voltage is between 47.2V – 56.8V, Nominal Voltage is 51.2V. The LiFePO4 (Lithium Iron Phosphate) battery is free of cobalt and has a cycle life of over 6000. This battery is IP65 rated and can be mounted to a wall or the floor. Features Modular, stacked design Excellent safety of LiFePO4 battery Winner of the All Quality Matters award Remote firmware upgrades