How long does it take to Charge a Battery?
The time it takes to charge a battery depends on a few things.
- How discharged is your battery?
- What is the capacity (Amp Hour or Ah) of your battery?
- What is the output current (Amps) of your charger
To determine the approximate recharge time of a discharged battery, divide the battery’s remaining capacity (Ah) by the rated output of the charger (amps). Then multiply the resulting number of hours by a factor of 1.75. This factor compensates for the declining output current during the charge cycle.
If the amount of amp hour discharged from your battery is known, you can use it instead of using the battery’s capacity to make your calculation.
So, for an example, let’s say you have 12 Volt 100 Ah battery that is discharged by 50% and you have a 10 Amp battery charger . The estimated charging time would be 8.75 hours.
A – Battery capacity = 100 Ah
B – Depth of discharge= 50%
C – Charge rate of battery charger = 10 amps
[ (A * B) / C ] * 1.75
[(100 x .5) / 10] x 1.75 = 8.75 hours
If you are wondering what size of battery charger you need, see this article on how to choose the correct charger.
