I forget to turn off the battery pack. The battery is drained out. Is it dead? It seems I can't recharge any more.
I think what has happened when I put my battery pack in the light case, the pressure inside the light case must have flipped the switch on.
You might try starting a charge cycle many times. The charger is probably reading zero and will not charge it. But if you can get a little energy in it. It might then take a charge. I have gotten ni-cad, and ni-mh batteries to come back from the dead. Has not always worked. If you lost a cell only replacement of that cell will fix it (or whole battery).
My Kindle was allowed to go completely flat - not used for 18 months or so. It took two days of charging to admit it was flat and a third day to actually charge it. Sent from my 8070 using Tapatalk
Both the type of battery and the design of the charger will determine if you can or can't re-charge a completely discharged battery.
Are you slightly mechanically inclined? If so, you can try to parallel 2 batteries of the same voltage. Not sure what the flashpoints produce. But for example Ni-CD - Ni-MH AA are 1.2 v. If you parallel a good charged battery with a dead battery of the same size (positive - positive, negative-negative). Current from the one will flow into the other. From what I have read a fully discharged battery may form crystals between the cells. And doing this parallel for 20-30 second might clear the crystals (they will heat up and melt). With the shorts cleared, the batter pack might take a charge the normal way.
