26 AH mobility batteries

Since there are only 1.5 volts above 11.4 volts that represents the full range of charge, we can divide the difference that we just calculated by 1.5 volts to get the percentage of charge remaining. 0.75 volts / 1.5 volts = 0.5 or when expressed as a percentage, multiply by 100 and get 50%. Here’s the procedure written as a formula that is applicable to 12 Volt Batteries: OPEN CIRCUIT BATTERY STATE OF CHARGE (SOC) CALCULATION % Charge = SOC % Charge = ((Measured Battery Voltage – 11.4 volts) / 1.5 volts) x 100