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Message: Re: Battery charging question.
Changed By: MarcW
Change Date: October 15, 2018 03:29PM
Re: Battery charging question.
Change Date: October 15, 2018 03:29PM
Re: Battery charging question.
[quote="Guenter in Ontario"]
Mark, I don't understand how a 12V battery showing a reading of 12.5v is down around 75%. That would mean that fully charged, it would have go give a reading of around 16.5v. I've never seen a reading that high. I'm not sure how that's possible on a 12V battery.[/quote]
My info is a 12V battery is made up of 6 cells, wired in series, with each cell contributing 2.2V (fully charge) to the battery's total voltage. Fully charged that is 6 * 2.2V or 13.2V fully charged. After "resting" for 12 to 24 hours the voltage level will drop to above 2.1V per cell or 12.7V.
Forgot to add: So a battery that after 12 hours resting is down to 12.5V indicates a battery with one or more cells that can't hold a charge very well. A battery never gets any better from this point.
Mark, I don't understand how a 12V battery showing a reading of 12.5v is down around 75%. That would mean that fully charged, it would have go give a reading of around 16.5v. I've never seen a reading that high. I'm not sure how that's possible on a 12V battery.[/quote]
My info is a 12V battery is made up of 6 cells, wired in series, with each cell contributing 2.2V (fully charge) to the battery's total voltage. Fully charged that is 6 * 2.2V or 13.2V fully charged. After "resting" for 12 to 24 hours the voltage level will drop to above 2.1V per cell or 12.7V.
Forgot to add: So a battery that after 12 hours resting is down to 12.5V indicates a battery with one or more cells that can't hold a charge very well. A battery never gets any better from this point.
Original Message
Author: MarcWDate: October 15, 2018 03:26PM
Re: Battery charging question.
[quote="Guenter in Ontario"]
Mark, I don't understand how a 12V battery showing a reading of 12.5v is down around 75%. That would mean that fully charged, it would have go give a reading of around 16.5v. I've never seen a reading that high. I'm not sure how that's possible on a 12V battery.[/quote]
My info is a 12V battery is made up of 6 cells, wired in series, with each cell contributing 2.2V (fully charge) to the battery's total voltage. Fully charged that is 6 * 2.2V or 13.2V fully charged. After "resting" for 12 to 24 hours the voltage level will drop to above 2.1V per cell or 12.7V.
Mark, I don't understand how a 12V battery showing a reading of 12.5v is down around 75%. That would mean that fully charged, it would have go give a reading of around 16.5v. I've never seen a reading that high. I'm not sure how that's possible on a 12V battery.[/quote]
My info is a 12V battery is made up of 6 cells, wired in series, with each cell contributing 2.2V (fully charge) to the battery's total voltage. Fully charged that is 6 * 2.2V or 13.2V fully charged. After "resting" for 12 to 24 hours the voltage level will drop to above 2.1V per cell or 12.7V.