I'm looking for some help as I plan my auxiliary battery installation. To start with, I need to figure out where to put the batteries. There doesn't seem to be any room in the engine compartment for 2 or 4 deep cycle batteries, so I was planning to put them inside the passenger area. But then I read somewhere that deep cycle batteries off gas, which is not good for your health, and they should be put either in the engine compartment or under the van somewhere.

I saw a picture of how Ford does it in the factory... there's a metal box mounted under the vehicle on the passenger side of the van, next to the main frame. So I started wondering... what's the best way for me to add a battery compartment under my van?

First of all, is this what I should be doing? If it is, here's how I picture it:

I could make a metal box that has an open top with an angle-iron flange around it (in other words, the angle iron would be welded to the box and flair out from the top). Then the box could just drop inside a square hole in the floorboards while the flange keeps it from falling through and holds it in place. I could then through-bolt the flange to the floorboards. Then my cabinets could be installed on top of the battery compartment, giving me access when I pull the drawers out.

Thoughts?

 

Auto parts stores sell battery boxes (plastic). You can weld simple braces to the undercarriage (as close as possible to the front). Mine was right under the Side passenger double-door, next to the beam.

What devices (loads) are you planning to feed? Circuiting? How are you re-charging it? Separation of aux battery from the starting battery? Inverters? Ventilation?

You can run a search in this forum for 2nd battery setups. Plus Ford pickup forums have tutorials on building this as well.

 

Thanks for the reply. I have some planning to do. All I know right now is that I want to run a refrigerator, a ventilation fan (already installed in the roof), and a 1500 or 2000 watt converter. I don't need to run a microwave or a tv or anything like that. I mainly use my van in the spring/summer/fall months in the west, and I mostly need to keep food/drinks cold and the van ventilated. I want the van to perform well in the hot desert, so I want to add a solar charger, and am hoping I can "stub" that out, so I can add it later.

I think the refrigerator will require at least 2 batteries, but maybe 4.

As I read more about it, I can see that it's important to ventilate the batteries, and I don't think I want them inside the van. I found this website that sells plastic and aluminum battery boxes, but it doesn't mention how the boxes get ventilated:

Battery Box, Tray and Case | Battery Boxes, Trays & Cases - Remy Battery

How would I mount one of these boxes under the van? How do you access the batteries? Would the mount allow you to take the entire box off to access the batteries?

 

I bought my battery case/box at the local Advance Auto Parts. I think I paid $ 17. The box had holes/gaps for ventilation.

IIRC the height was about 1 foot. I welded 2 shelf angle brackets into the van's beam and created a tray. The boxes were strapped to the tray.

I also purchased a smaller 2nd box for the 500 W inverter and the switches. Inside the 2nd box, I installed a small fan for more ventilation. Because of the design of the box, air goes in from the top, while water sprinkler does not. I drilled very small weep holes in the bottom. All devices were installed inside, along the side in the center, lifted off the bottom.

Never had an issue with water or temperature.

My loads were 3-4 times smaller than yours. I am not sure how many batteries you will need. If you will use the alternator to provide some re-charging you may need to upgrade to a HD alternator. My deep-cycle marine battery (I think I paid $ 140) for it was recharged by solar panels, however it had relay then when solars could not re-charge quick enough, a relay would switch to Alternator re-charging. Since I needed to replace the Alternator anyhow, I think I paid $ 250 for a HD Alternator, vs $ 180 for the regular one.

I used 2nd battery for the audio-visual system, since I upgraded it all. Plus a few other small things.

I actually spent more time devising and building the scheme of separating both batteries and switching some OEM circuits to the 2nd battery feed. I drew a wiring diagram and consulted with a electrician friend of mine too.

 

Another thing -- my aux battery setup was designed to run its full load (400-500W) for 1 or 2 hours, not overnight. To run 1500-2000w overnight, I think you will need a portable generator.

Inverters:
I have bought maybe 7-8 inverters in the last 10 years, and I use them in all my vehicles. A couple of things are important.

1- Quality.
2- They are noisy and you definitely don't want them inside the cab.
3- Their internal fan may or may not be enough. I now always supplement it with a $ 7 fan where-ever I install them.
4- Don't rely on inverter for protecting your equipment (especially if they are expensive).

 

The power converter would only be used to power a computer, grind coffee beans, boil water in an electric tea kettle... stuff like that. I don't need power for long-term use. The tea kettle I use at home requires 1200 watts, so I figure a 1500 watt converter should do it.

Can you explain what you mean by:

"All devices were installed inside, along the side in the center, lifted off the bottom."

Do you mean that you lifted the van off the ground and then installed the boxes?

Also, what do you do when you need to get into one of the boxes? Do you unstrap the boxes and take them off their trays?

 

Yes, unstrapped them.

 

I see... Thanks! Sounds like a good plan! Can you explain how you hooked up the additional fans? You mentioned that you installed one in the box that holds your inverter, but did you also add one to the battery box?

 

No fan in the battery box. Depending on where you are too cold and too hot is not good for the battery. On more thing, I did install a small rubber padding under it to absorb some vibration.

I installed a switch for the driver to turn on the inverter and the 110 V loads. It was not running all the time. Like I said, I transfered some circuits from the starting battery to the 2nd battery, such as the radio and sound system, plus the feeds to the conversion-added electrical panel (lights, vacuum, etc) and some receptacles. I just wanted to use them in 1-2 hour stops without fear of discharging the starting battery.

Another thing -- protection. You need to kill the power draw when voltage drops below certain point. I had a disconnect switch that worked automatically. Inverters usually have their own, but other loads don't.

Another thing -- instrumentation: I also installed a voltmeter for the driver to check the 2nd battery, just like the starting one.

I know people have setups that the 2nd battery could be used as the starting battery, if that one fails.

You really need to draw a wiring diagram, to figure out what conduit and wire you will need. That's a job in itself.

 

About the fan: when the driver flipped the switch to turn on the inverter (through a Radioshack relay), that's when the fan would turn on. Just a simple 12 V feed from the switch/relay.

You really need to draw this for yourself.

 

i hung two golf cart 6v batteries off the right rear frame of my extended '95 E350 using a pair of these (these are made by AFCO btw):
Weld-In Battery Box

wanted to use these but was too broke:
Drop-out Battery Box

thought long and hard about where to put the batteries and decided against under the steps - too much cutting up of things to get them high and tight and too close to the cat.

i removed the factory battery tray and associated hardware and relocated the starter soleniod to the pass side. battery went over there too on the ambulance second battery option tray and bracket.

ran 0ga cable in a fiberglass insulating sleeve to the engine compartment from the rear. put a 250A ANL fuse and fuseholder w/in 8" of the rear batteries and ran the eng compartment end to one terminal of a constant duty solenoid. the other terminal has a 2ga jumper coming from the constant post on the starter solenoid which has been relocated to the passenger side (as has the underhood battery.)
from the solenoid there is a 2ga cable that goes to another 250A ANL fuse/holder mounted w/in 8" of the upper 200A 3G alternator. the starter solenoid post, that has the 2ga cable to the constant duty solenoid, also has a 2ga cable to the front battery as well as a 2ga cable to another 250A ANL fuse/holder the other end of which runs to the lower 200A 3G alternator. the primary purpose of the front fuses is to prevent some yoyo from connecting jumper cables up reversed and damaging one or both of the alt's.

as i am now running two independant batt/charging systems, i needed to monitor them both as well as have an idiot lite for the times my wife (god love her) drives my van. so i purchased an Autometer voltmeter with the same face to match the oil/water/tranny temp gauges in the pillar pod. i rolled the bezel off and mounted a miniature lamp and red lens in the gauge face and mounted the charge bypass resistor in the back of the case. i mounted the gauge using an add-a-gauge plastic piece for a Superduty F350 steering column.

wiring requirements were fairly simple...
grounds: 0ga cable to the frame both front and rear, 0ga cable from engine block to frame, 4ga from frame to body. a bosch relay, 5A fuse/holder, and a piece of wire thru the firewall to the new voltmeter and a second to trigger the constant duty solenoid via a relay and momentary switch.

all Ford van stuff runs off the upgraded oem battery system and the stereo and video etc run off the second alt and batt setup.

regrets? i wish i had found the cool battery filling system that i ended up finding before i did the install - and cut the interior floor for above access to the top of the rear batt's. altho it is only a 2 x 12 inch cutout so it isn't so major... . i wish i could have afforded the drop out trays - but i will do them eventually...

you could move the spare to a tire carrier on the rear door and build yourself a big battery tray behind the rear bumper. i've done that for someone - and it was motorized and operated by his car remote. we had 12 batts there with room for more

i recently did an ice cream truck for a buddy. we installed a comercial freezer and a 4kw inverter. he purchased a cheaper unit off ebay, so before installing it i took it apart for examination. when i got finished with the repairs, i mounted the inverter vertically on a board mounted to the left rear sheet metal. been fine for almost a year.

 

Wow, thanks for your detailed post! Under what circumstances would someone want to replace the factory alternator?

 

Thanks for sharing this. A few questions:

When you say "upper alternator" "lower alternator" "both alternators" are you talking in fact of 2 alternators? If so, I would be very curious why and how this was done.

When you say "starter solenoid" do you mean "starter relay" mounted on the radiator support (in the case of 1995 E-150)?

Did you have any problem with water splashing the battery connections --- based on the open box you used?

 

I upgraded / replaced the OEM alternator to a heavy-duty one. It's done all the time when installing 2nd batteries, although there plenty of people that run both batteries on the regular alternator.

 

Deep cycle batteries require a slow charge at no more than 2.5 amps or you'll burn the plates out of them, you can't tie them into the vehicles electrical system because the alternator will kill them. The wheelchair conversion company installed one in my van in the rear to run my lift, it got overheated and popped the top, they replaced it with another, that the plates burned up, so with comments from other experiences with mine, slow charge only.