The Hikoki BSL1850 5.0Ah 18V Battery is the same size as the 3.0Ah version but offers up to 200 more power. The battery includes 3 way protection including deep discharge and overload protection. Fast re-charge plus energy saving extends the life of the battery and ensures that you can keep working with less downtime. Up to 1,500 cycles rechargeable through multiplex protection circuit that prevents overload, overcharge and over discharge The Hikoki UC18YSL3 Multivolt Fast Charger is compatible with 14.4V and 18VLi-Ion slide style batteries. The charger has a cooling function so that the battery stays at the optimum temperature when charging . This is designed to prevent the battery from overheating resulting in a longer battery life. It will not charge a hot battery until it has cooled therefore protecting both the user, tool and battery. The two colour indicator light informs at what stage charging is at. Charging time can be between 15-38mins subject to battery.