# 12v battery charging issue

#### imran_bappy47

Joined Aug 24, 2020
4
How is it possible to charge a 12v battery with a 6v voltage regulator rectifier charger??

I know few people who are using a 6v voltage regulator rectifier charger to charge their motorcycle 12v battery and they are using for more than 2 years !!! I don't know how logically that's possible to happen !!! Can anybody explain the matter?
I have attached the 6v charger photo and photograph of the 12v 7Ah battery for your better understanding.

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#### trebla

Joined Jun 29, 2019
209
Unmodified 6V lead-acid battery charger must give maximum 7.2V on charging. Minimum voltage per battery element is 1.7V, for 12V battery is minimum (empty state) voltage 6 x 1.7V = 10.2V. Maybe two 6V chargers in series give desired results, i'm not sure.

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#### imran_bappy47

Joined Aug 24, 2020
4
They are using a single charge, I have uploaded the photo of that 6v voltage regulator rectifier charger, this Single unit is using to charge the battery.
Yes, the charger's output is 7v on charging.

#### trebla

Joined Jun 29, 2019
209
For charging 12V battery you must give 14.2-14.4 volts to battery at required charge current. Current always flow toward smaller voltage potential and your battery will power your 6V charger (if not reverse diode present) until battery will be dead.

#### ericgibbs

Joined Jan 29, 2010
10,765
hi imran,
Are the 2V Cell to Cell links accessible on the 12V battery.?
If so you could connect the 6V charger from one terminal of the battery to the 6V link.
Charge one group of 6V and then the the other group of 6V.

On older types of wet lead acid batteries the individual 2V cell links were visible.

E

#### imran_bappy47

Joined Aug 24, 2020
4
hi imran,
Are the 2V Cell to Cell links accessible on the 12V battery.?
If so you could connect the 6V charger from one terminal of the battery to the 6V link.
Charge one group of 6V and then the the other group of 6V.

On older types of wet lead acid batteries the individual 2V cell links were visible.

E
They are using Dry cell aka maintenance-free AGM type battery with that particular rectifier charger that I've uploaded.

#### imran_bappy47

Joined Aug 24, 2020
4
For charging 12V battery you must give 14.2-14.4 volts to battery at required charge current. Current always flow toward smaller voltage potential and your battery will power your 6V charger (if not reverse diode present) until battery will be dead.
Exactly, that's the logic.
but I've seen what I've told and trying to understand...

#### MrChips

Joined Oct 2, 2009
21,838
Maybe the 6V regulator rectifier controller is blown and the 12V battery is getting the full rectified output from the generator.

#### Dodgydave

Joined Jun 22, 2012
9,425

#### BobTPH

Joined Jun 5, 2013
2,538
The device you show is not a power source. And it includes what is needed to make a charger, i.e. a bridge rectifier.

If you can bypass the regulator and put about 12VAC in, it could charge a 12V battery.

Bob