Battery charger for dead battery
#1
Member
Thread Starter
Battery charger for dead battery
I bought a Black & Decker BC15BD battery charger. When my car battery died due to a small light left on, it would not charge it or jump start the car. When I called B&D, I was told that the unit will not charge a completely dead battery. I would like a charger that works on a dead battery. Can you recommend one? Thank you.

Top Answer
08-05-19, 01:15 PM
Many of the new chargers will just sit there and do nothing unless there is a certain voltage on the battery. Some are around 8v while others are closer to 10v for a 12v battery.
#2
More and more of today's battery chargers are called smart chargers. They deliberately don't charge dead batteries to eliminate battery damage or possible explosion.
You need to get a basic 2A/10A non automatic battery charger. You could use one of these basic chargers to precharge the battery and then switch over to your B & D unit.
You need to get a basic 2A/10A non automatic battery charger. You could use one of these basic chargers to precharge the battery and then switch over to your B & D unit.
#3
Forum Topic Moderator
While I'm not familiar with that battery charger I would think it should charge a dead battery ... but it might not be instantaneous. How long did you leave the charger on the dead battery?
edit,
Just read Pete's response - I wasn't aware of smart chargers
edit,
Just read Pete's response - I wasn't aware of smart chargers

#4
Member
Thread Starter
Thanks PJ!
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#5
Many of the new chargers will just sit there and do nothing unless there is a certain voltage on the battery. Some are around 8v while others are closer to 10v for a 12v battery.
#6
A totally dead battery may not take any type of charge. The plates may be damaged. How old id the battery to begin with? If brand new and discharged by a light then it should charge but if 2 or more years old and totally discharged, it may not take a charge at all.
TomVZ
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clancy
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#8
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It doesn't need to be all that new for a battery charger to use the so-called "smart" technology. I have a Sears automobile battery charger that is more than twenty years old, (maybe closer to thirty years old) that will not charge a totally dead battery.
If the charger has the feature that causes it to "beep" if you connect the leads incorrectly then it will NOT charge a completely dead battery, even if you leave it connected forever.
If the charger has the feature that causes it to "beep" if you connect the leads incorrectly then it will NOT charge a completely dead battery, even if you leave it connected forever.
#9
It is not recommended to reduce a vehicle battery to below 10 volts as its life will be shortened.
To take it to a few volts or even zero volts will do damage and it might work if you bring it back but will have minimal capacity.
As said, a manual charger may get it to hold a charge but you would do well to just buy a new battery.
To take it to a few volts or even zero volts will do damage and it might work if you bring it back but will have minimal capacity.
As said, a manual charger may get it to hold a charge but you would do well to just buy a new battery.
Norm201
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