Adding second battery box

[nickcrowhurst]

I'm planning to add a second battery box in the usual position at the front of our 1988 Excella. I've got a used box and door from the local wrecker's yard, and would appreciate advice from you all on a few points:-
1. It appears that the plastic box is sandwiched between the aluminum skin and the door surround using self-tapping screws. The flange on the plastic box is not wide enough to be pierced by the screws, other than by semi-circular bites out of the plastic. This means that the hole cut in the skin will need to be very accurate, so as to force the plastic box to fit without leaks. It would help to glue the box to the back of the door frame before fitting, but that looks tricky. I just have to cut the hole very accurately, so what tool would you suggest? I have aircraft style snips, but these would distort the metal. I have an electric jig saw. I have a 4 inch electric disc grinder. How about a Dremel?
2. To seal between the box and the skin, would you use Vulkem, or some of the thick sticky tape used for installing windows?
3. I see the existing live red wire runs from the battery to the Univolt via what appears to be an isolated thermal breaker or fuse attached to the inner skin of the trailer. I presume I should add a similar device to the new live wire from the second battery, rather than share this one device by connecting both live wires to it. What is this device, what is it's rating, and is there a particular source for these?
4. I am going to replace the Univolt with an Intellipower plus Charge Wizard. I presume this has no effect on these plans. Are there any other points I should consider before plunging some sharp tool into that vulnerable aluminum?
Many thanks, in advance. Nick.

[Silvertwinkie]

The one that came with mine was a metal box...you can check out the pics of it here:

http://www.airstreamphotos.com/photo...r=1937&thumb=1

Eric

[nickcrowhurst]

Eric, thanks, but in the Excella, the battery boxes fit inside the trailer, underneath the couch, behind lockable doors with drain holes for rain water, and vent holes for hydrogen. Nick.

[Navigator]

Nick
Do you really Need that much more 12v capacity.
Perhaps an Optima Blue, or Optima yellow battery might get you the results you desire. IMHO.
Dick

[Silvertwinkie]

My bad....

As for needing two batteries, I can tell you first hand that while on a week boondocking, both batteries held us all week long with lights on, stereo on a good portion of the week.

I have heard some folks can last almost 3-4 days with constant draw with one battery. We lasted 7 full days and the batteries indicators were at 3/4 by the end of the week. If you have fantastic fans, it will drain even further. I am beyond glad to have 2 batteries in my coach.

One other off the wall suggestion would be to get one of these rather than mod out the coach:

http://www.hondapowerequipment.com/eu1000.htm

Or place two of these together:

http://www.hondapowerequipment.com/eu2000.htm

Of course I know that it's fairly expensive...........but I have heard great things from folks that have them. This would mean that you could run the gen a few hours a day if you are under heavy loads and not run out of power (unless you run out of gas)!

Eric

[74Argosy24MH]

The jig saw with a very fine bladewill give the cleanest cut, but if you are going to have to run the base over rivets it will get a little tricky. If you use the die grinder do a little at a time to let the metal cool, too much heat and it will warp.

John