BL1840B 18V LXT 4.0Ah battery

The BL1840B is 18 volt battery pack with a capacity of 4.0 Ampere hour for the Makita 18V LXT battery system.

The battery pack has a black plastic rounded rectangular housing. On the front is a single gray plastic latch which has to be pushed while the battery is pulled forward to release it from the machine.

The electrical contacts are in the the yellow plastic piece on top.

Inside this battery pack are ten 18650 Lithium Ion cells and battery management electronics to prevent damage to the cells by overheating.

On the back there is charge indicator with four red LEDs and a push button to activate it.