I took apart a dead Roomba Battery pack to see if I could replace a few cells and found that one of the battery's polarity had switched from negative to positive. I've never seen this. Luckily it was at a very low charge. Do you know how to reverse polarity on a NiMH battery so I can reuse it? Or am I out of luck?
It's not wise to mess with NiMH batteries. Touching the wrong wire to the wrong spot has been known to explode/catch on fire. Normally the only way a battery can reverse polarity is if it was completely dead, and somehow was hooked up backwards. If it was just one battery out of a battery pack(like cordless phone batteries are nothing but rechargeable AA/AAA batteries hooked up). If you're skilled and everything is still hooked up, you can buy a rechargeable NiMH battery and hook it up the exact way it was with the others. (assuming it's the AA/AAA battery sequence and not a special shaped battery)
