How do I Rebuild a Bosch 36V Battery?

lithium battery on white image by Yasen Pramatarov from

Technological advances in battery design mean that cordless power tools can deliver as much power as corded tools, but are safer to use and totally portable. The development of lithium ion cells has revolutionised the voltage and output a Bosch battery pack can produce.

The commonly known nickel cadmium and nickel metal hydride cells produce 1.2 volts while lithium ion cells produce 3.6 volts, retain more energy and weigh less. A Bosch 36-volt battery only requires 10 lithium ion cells compared to 30 NiCad or NiMH cells, and if you need to rebuild your Bosch 36 volt battery, it's easier and quicker.

Remove the Bosch 36-volt battery pack from your device and place on a workbench. Remove the screws holding the battery cover in place using a small Phillips screwdriver. Remove the cover.

Press the "lock" switch located on the top of the Bosch battery pack. This releases the inner battery container. Slide the container out. You see the 10 lithium cells, wired in series.

Remove the metal covers that connect the cells. There are several on the top and bottom of the pack. They are held in place by plastic clips. Simply lift the clips to release the covers using a small screwdriver.

Slide each battery cell from the container making sure you note the way the cells fit in place. It's sensible to write it down or draw a rough diagram as you must insert the replacement cells the same way.

Wrap the lithium ion cells in paper and place them in a plastic bag and dispose of them. Lithium cells, unlike NiCad or NiMH, are environmentally friendly and can be disposed of in your regular trash.

Insert the 10 replacement lithium ion cells into the inner battery container. Ensure you refer to your notes or diagram so you put them in correctly.

Replace the metal covers. Push the plastic clips into place so the cells are secure.

Insert the inner-battery pack into the outer casing. Press the switch on the top into the "locked" position.

Replace the outer battery cover. Use a Phillips screwdriver to tighten the screws in place.

Put your battery into the battery charger. Let the battery charge for about half-hour to ensure all the cells are fully charged and then put your rebuilt Bosch 36 volt battery into your device.