80V 2.5 Ah and 40V 5.0 Ah Lithium-Ion Battery 80V 2.5 Ah and 40V 5.0 Ah Lithium-Ion Battery Dual Voltage Compatibility: Works with both 80V and 40V tools. In 40V tools, it automatically switches voltage for up to 2X the runtime compared to a 40V 2.5 Ah battery. High Performance: Designed for ultimate power and performance with industry-leading Li-ion battery cells that are individually balanced and tested. Smart Features: Fuel Gauge: Displays the state of charge. Thermal Control: Extends battery life and runtime by minimizing heat. Impact Resistance: Protects against drops and vibration for enhanced durability.