Can a Standard Lead Acid Battery be Used to Charge an AGM Battery

Question:

My van presently utilizes a regular lead acid battery. I wish to add an AGM house battery for travel/camping, and utilize the van charging system to charge the house battery through a voltage sensing relay. Question is: Will this work, without detriment, as the batteries are of different types?

asked by: Steve

Expert Reply:

You can use a standard lead acid battery to charge an AGM battery if you have the correct battery charger as not all will allow for this. I cannot speak of the voltage sensing relay that you are referring to but I can confirm that the Redarc In-Vehicle BCDC Battery Charger will allow you to charge an AGM battery using a standard lead acid battery. This charger is offered in two different capacities, part # 331-BCDC1225D for 75-200 Ah batteries and part # 331-BCDC1240D for 200+ Ah batteries.

The Redarc BCDC is going to convert the output of your standard lead acid battery into a low voltage and slow charge rate that an AGM battery requires which is what allows it to be used in this sense. You cannot hook the two batteries together with just a standard relay as it would not have the technology required to adjust the charge.

expert reply by: Conner L