Charged

When a battery is being charged, you will get a higher voltage reading than you would find at rest. Most renewable energy charging systems will charge a battery until the battery reaches 14.5 volts and then will automatically shut off. The battery voltage will drop slowly. The most accurate way to check the true charge state of a battery is with a hydrometer. A specific gravity of 1.260 in a lead acid battery means it is fully charged. As a battery discharges it will fall to 1.120 when discharged. The ratings are at 77F. If the temperature is lower than 77F then the specific gravity will be inflated. Premium hydrometers will have a temperature and give you a compensation factor.

Correction factors:
	130 degrees F	+0020
	120 degrees F	+0016
	110 degrees F	+0012
	100 degrees F	+0008
	90 degrees F	+0004
	80 degrees F	0000
	70 degrees F	-0004
	60 degrees F	-0008
	50 degrees F	-0012
	40 degrees F	-0016
	30 degrees F	-0020

Percent charge Voltage
	100%	12.60
	75%	12.35
	50%	12.15
	25%	11.95
	discharged	11.85 or below

Offered by Steve.