Makita BL1820 18V 2.0Ah Li-Ion Battery The Makita BL1820 2Ah Lithium-Ion Battery is both lightweight and shock-absorbing. The Li-ion range delivers 430% more working capacity during it\'s lifetime compared to Ni-Cad and is 40% Lighter than Ni-MH. The Li-ion has minimal depletion of power during use or in storage over it\'s lifetime. FEATURES Low self-discharge Energy storage capacity (2Ah) for long run times With overload, over-discharge and overheating protection Star Protection Computer Controls: The demanding applications you take on every day are also demanding on your cordless tools and batteries. You rely on your tools, so Makita created STAR Protection Computer Controls. STAR Protection is communication technology that allows the tool and battery to monitor conditions and exchange data in real time to protect against Overloading, Over-Discharging and Over-heating. Overload Protection: High-drain applications require maximum battery power. Makita tools and batteries are engineered for industrial applications, but sustained peak demand can overload the tool. Makita’s STAR Protection Computer Controls™ allow the battery and tool to communicate and protect your tool and battery from overload by cutting power when put under abnormally high current draw. Over-Discharge Protection: Lithium-ion batteries are engineered for longer, sustained performance. But running a battery until it’s “dead” empty can damage the cells. Makita STAR Protection Computer Controls™ monitor battery charge capacity, and if the battery is too low to complete the application it will cut power in order to extend battery life. Over Heat Protection: Extreme heat is the enemy of ALL batteries. It can make batteries charge slower, damage battery cells, and reduce battery life. Makita STAR Protection Computer Controls™ monitor battery heat during operation. If the battery reaches a certain level of heat it will cut power to the tool. SPECIFICATION Battery Chemistry: Li-ion Voltage: 18V Battery Capacity: 2.0Ah Weight: 0.35kg Charge Time (DC18SD): 42 mins Charge Time (DC18RA/DC18RC/DC18RD): 18 mins