Customers often ask us about the ideal charging current for recharging our AGM sealed lead acid batteries.
We have the answer: 25% of the battery capacity. The battery capacity is indicated by Ah (Ampere Hour).
For example: In a 12V 45Ah Sealed Lead Acid Battery, the capacity is 45 Ah. So, the charging current should be no more than 11.25 Amps (to prevent thermal runaway and battery expiration). Importantly, if you have other equipment connected to the battery during chargning, it also needs to be powered, so you need to add that to your calculations. In this example, if your battery is connected to a load of 10 Amps, the charging current needs to be 21.25 Amps.
The voltage of charging is also important. AGM batteries need to be charged with a voltage of 2.4 volt per cell. A 12-volt battery set has 6 cells, so you need to charge it at 14.4 volt.
Luckily, most chargers do all this automatically.
Keep the questions coming!
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