Useful to know if your power tool's cordless battery won't charge and certainly worth a try if your battery looks to be fubar'd
Flat Cordless battery hack
- Thread starter littleade
- Start date
I tried that, doesn't work.
Yes the dead battery will show it's charging with the red light but it won't hold a charge for more than a couple of minutes.
Maybe my battery was too far gone ...dunno.
Wouldn't cost anything to try.
Yes the dead battery will show it's charging with the red light but it won't hold a charge for more than a couple of minutes.
Maybe my battery was too far gone ...dunno.
Wouldn't cost anything to try.
Lithium ion battery or Ni-cad/Ni-Mh? If latter, forget about.
The method only works with lithium batteries, as these tend to go into self preservation (sleep) mode, if not used for long periods of time. So just need a jump start.
If you haven’t got a suitable cable handy to use, you can improvise with paper clips or even pair of utility (Stanley) knife blades. You only need to leave it for mere few seconds.
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My bike has a lithium battery and had precisely this problem. I got it to start charging by briefly connecting a 9v battery (the type for small portable radios) this then fooled the charger into thinking that there was some power so the charging started. Beware there are lots of caveats re lithium batteries particularly regarding charging.
tom
tom
There's a really good reason why they lock out.
If the cell voltage is too low, and you charge it, there is a risk of the cell bursting the internal insulation, in which case it has an internal short circuit, and whatever energy is left in it will be dumped in double quick time through the short.
This will get very hot, and will probably ignite the cell, and the rest of the battery. You won't put it out.
If you do fool the charger / BMS into allowing charging, you might save the battery, or you might burn down your house.
Don't let them get over-discharged and you won't have the lock-out problem. (And don't try to charge one at below zero temperatures either. )
If the cell voltage is too low, and you charge it, there is a risk of the cell bursting the internal insulation, in which case it has an internal short circuit, and whatever energy is left in it will be dumped in double quick time through the short.
This will get very hot, and will probably ignite the cell, and the rest of the battery. You won't put it out.
If you do fool the charger / BMS into allowing charging, you might save the battery, or you might burn down your house.
Don't let them get over-discharged and you won't have the lock-out problem. (And don't try to charge one at below zero temperatures either. )
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