What batteries do I need?

"Hi @sjakila_ ,

As long as they are NiMH AAA rechargeable batteries it will be OK.

Having batteries with solder tabs - example only is prudent so as to make for an easier connection because without them you may have to apply too much heat to the battery when you go to solder them back in.

Having larger capacity batteries would mean that it would last longer between charges but conversely it will also take longer to fully charge."