Thread: cooked cordless drill batteries

Originally Posted by Brian Hjelm

When mobile phones were the size of a subway roll and the battery pack as big as your hand, when they got sick we would bung the batteries in the freezer over night after giving them a shock charge with the 12V car battery charger until they were almost to hot too touch. Sometimes worked, sometimes not. Worth trying.

I've seen problems with so-called 'smart chargers'. If the voltage is too low they won't charge at all.

As Brian stated, sometimes hitting them with a charge from a crude charger (old fashioned car battery charger) until the voltage picks up then putting them on the correct charger brings them back to life.

Won't fix a dead battery but might allow you to charge it and see whether it holds a charge.


Colin

short version.

if they are lithium-anything dispose of them completely and appropriately replace with new lithium packs or buy a battery shell and repack with nicad/nimh and replace the charger if its not compatible.

if they are nicad they may respond to "shocking" which is a brutal application of voltage that breaks up the crystals that form in the battery producing the "memory" effect.

if they are NIMH or the shock doesnt work, break the pack out head to jaycar and buy the same number and type of replacement cells and solder the new ones back in the casing.