How does temperature affect a batteries available capacity and charge time?

A batteries available capacity varies at various temperatures. As the ambient temperature rises a batteries ability to deliver current increases. As the temperature falls, so does the batteries ability to deliver current. Even though battery capacity at high temperatures is higher, battery life is shortened. Battery capacity is reduced by >50% at -27˚C / -22°F - but battery life may be increased by as much as 60%. Alternatively, battery life may be reduced in half for every 10°C / 15°F over 25°C / 77°F. This is true for any type of Lead-Acid battery. NOTE that even though a batteries ability to deliver and receive current (charge) goes up as temperature rises, operation at extreme temperatures above 30˚C / 86˚F will shorten the life of the battery. Conversely a batteries ability to deliver and receive current drops as temperature drops and operation at extreme temperatures below 10˚C / 50˚F will dramatically decrease available capacity or run time and will dramatically increase the time required to re-charge!

To calculate approximate capacity correlation due to temperature, add or subtract the % adjustments shown in the following table. Note that the % changes with the discharge rate: