Thread: Do I need to disconnect my cranking battery to charge it?

I have a 2015 Defender. The manual states that to charge the battery I should remove it.

My practice has always been to disconnect the +ve terminal and charge it without removing it. Plenty of ventilation, of course.

My question is, do I need to disconnect it to charge it or not?

Thanks in advance.

Hi MY, just charge the battery in place.

Don’t even disconnect any of the battery cables.

Make sure you use a multi stage battery charger and connect the battery charger’s positive ( + ) lead to the battery’s positive ( + ) terminal.

But connect the battery charger’s negative ( - ) lead to an earth point, not to the battery’s negative terminal.

Where the cranking battery’s negative cable is bolted to the body, is a good earth point.

By connecting in this way, you will not interfere with the vehicle’s BMS.

The reason they want you to remove the battery is in case you use an older type single stage battery charger, which often, if not watched, can cook the battery, causing it to boil and spew battery acid in the battery compartment.