*This battery is designed to use with EcoFlow Power Kits Power Hub Self-heating:?With built-in auto-heating, you can use the batteries safely in temperatures as low as -4??F. Stackable and Expandable:?Available in two sizes, both 2 and 5kWh stack up to 3 for a capacity of up to 15kWh. Safety First:?Hot-swap enabled. Advanced BMS Protection?Power Kits Battery Management System protects against: Single-cell over-voltage protection Single-cell under-voltage protection Discharging over-current protection Discharging overheat protection Discharging low-temperature protection Charging over-current protection? Charging overheat protection Charging low-temperature protection