Forum Discussion

melton's avatar
melton
Explorer
Oct 31, 2016

Battery shopping

The time has come to replace my 6 Interstate U2200's, which are 7 year old group GC2 flooded deep-cycle batteries. I want to consider AGM's, especially because the main house battery tray has little clearance over the batteries, making it a bear to water them. I would appreciate suggestions, prices, and where to buy. I have Deka, Northeastern Battery, and Interstate dealers nearby.

My motorhome:
1990 Cruise Master 28', on a 1989 E350 chassis (yes, it's antique. I custom ordered it new)
Xantrex RS3000 inverter/charger, with charger settings for flooded, AGM, or gel. (Heaviest load used on it is microwave oven).
2 alternators, totaling 280 amp output, although 180 is the highest I've seen the ammeter go.
5.5 kw Onan Marquis generator.
Main house battery tray is 21" x 22", which will hold 6 GC2s or 4 group 31s. A second battery tray will hold roughly the same, but is oddly shaped.

We often boondock where generator hours are limited. So battery capacity is important.
When the motorhome is not in use, I keep a BatteryMinder on the batteries.
Solar is not an option.
What i would like to find is the most capacity for the money in AGMs.

12 Replies

  • The "best bang for the buck" are flooded GC2 from Costco.

    Trojan makes an automated watering system for their T105 (GC2 equivalent) and T1275 batteries. Trojan also makes a T105-AGM.
  • Some 100AH AGMs are 27 size footprint so replacing six 6s might be an issue for tray size. BUT--AGMs can go inside as long as you don't overcharge them so they pop their gas valves. So you can escape the tray. This gives you options as to placement and battery bank AH size.

    Note AGMs inside where it is heated, do not lose capacity in colder temps, which has the effect of more capacity than you would be used to in winter.

    Can't help with pricing per AH but just tossing in the additional placement factor

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