Dedicated trailer battery... What would you use?

[Rezarf <><]

Title says it all... almost.

I am building a trailer for camping/expedition style usage. I was wondering what you would buy and put in a dedicated trailer. Here are a few of my thoughts:

No starting power will be needed/used.

I would like to power:
A freezer fridge.
12v SHurflo pump.
A few LED lights.
Two 12v sockets for misc.
Maybe a laptop.

Any recommendations and personal experience would be appreciated.

Thanks!

Rezarf <><

 

[OS-Aussie]

I have two sealed units in my trailer for about the same type of use. I also have a trickle charger and solar panel to help charge. The amp hour rates are the important part as this is how long your toys can run. I think that you can't beat the sealed units, however the big RV / solar batteries can out perform these but are way heavier and have that habit of leaking acid while off road.

Don't forget to allow venting and add fuses to the circuits, and most important make sure that the batteries are secure and can move around. Fire is not your friend in the battery box.

This little project can be as simple or complex as you may wish to make it.

A plastic battery box should work for you needs to mount a battery, but there are some very nice stainless units for those with lots of $$$.
Then you need to plan out your circuits. Will you earth the trailer or run an earth to each switch / plug ?
Will you use a RV 12 fuse panel from eBay or even one with circuit breakers ? (I selected the in-line type fuses that match the ones in my Jeep) This does make running circuits and safety easier.
You will also need to secure and wrap any wires that you run to ensure that they don't wear and then short out.
Will your switches be inside of outside, if outside you need to use water proof switches of some type.

Good planning and installation makes a world of difference. But a well done 12v system sure makes your camping experience so much better.

 

[Mike S]

Drew

I used a pair of West Marine 105 AH marine batteries with a Guest dual battery charger mounted nearby. I think you need a 'house style' marine battery that can be discharged over and voer again. I do not think you need an AGM type - it's not worth the extra expense.

The batteries sit in a tongue box with vents and external 12V and charger plug socket. These are marine type fittings with rubber plugs. They run the Shurflo pump, provide charging for the sat phone and pwer for the tent lights. When I finally cave in and get a fridge, they'll power that. I don't really need two batts, but one is removeable sop that I can use it to run my trolling motor on the canoe.

 

[Scott Brady]

Group 31 AGM. Either a Lifeline, Deka or Odyssey

 

[spressomon]

2-Lifeline Group 31's in mine with charging via the 7-pin. You may want to use the same group size as your vehicle's battery (just in case you need to swap it in an emergency situation).

I primarily use the batteries (one would have been fine...but that was after I found out the wifey only goes with me once for every 10 times out =8^| ) for my ARB Flo light (1-amp draw) and the occassional locking of the trailer e-brakes; quick charge for my camera battery, etc.

If you are going to put a tent atop...you might want the 12V outlet handy for a tent light (ARB Flo light).

As for the fridge/freeze...you'll need to figure out how long you might run the fridge (and other battery draw devices) to determine what type and how many batteries you'll need in between charge cycles and/or PV use.

 

[DaktariEd]

I believe my trailer battery is an Odyssey...I'd have to check...that charges via the 7-pin connector to the Cruiser.

I also have a solar panel that I am testing this weekend to keep up the charge while base camping.

Another thought: The plastic battery tray broke during one trip. The threaded rod pulled right through the plastic. It just wasn't made for rugged use. Get something strong...

:sombrero:

 

[Mike S]

West Marine sells a very nice battery hold down system. A base that bolts to the mounting surface, a set of threaded rods (stainless) and a top piece that fits around the entire perimeter of the battery top. They will hold a Group 31 marine battery very well, and are reasonably priced.

I looked at the idea of using the 7th trailer pin to charge the batts, but determined that the ideal way to set that up was with an isolator, due to the amount of charge that the trailer batteries will require when used on a regular basis. I opted for a plug-in 110 marine charger instead, since it seems to charge well, and I can usually connect to recharge before both batteries are run down. I am considering the solar option as well.

Mike

 

[Grim Reaper]

That long 125lb punk in the middle the TEL 12-150
http://www.cdstandbypower.com/product/battery/vrla/pdf/tel_41_9028.pdf
Rated 150ah. They were tossing them at work because we don't have the Hazmat credentials to store them. They came in some decom gear and we had to pull them out before shipping...got a couple off the recycle guy when the company arranged to get rid of them and have a couple more I am looking at getting if these 2 check out.


They were sitting at 5.6v for an undetermined amount of time. Been cycling it and so far it seems good but its brutal on my cheap charger. It took 10 hours of 10 amp charging to get them back of to 12.54 volts. Need to get a better charger for them. The size is pretty sweet. just a little over 5 inches wide and 23 inches long.

Plan to mount one on my Airstream, one on the expo trailer one on the Airstream for a house battery, one on the tow rig and one on the 4Runner to run fridges and stuff. Little over kill for the trucks for second batteries but the price was right.

 

[Rezarf <><]

Thanks guys, this is really giving me some good ideas.

I love the marine market, being a former Florida boy I am experienced in most things marine... and the marine market crosses over well into the off road enviroment.

Now, I have a few questions...

1. For you guys running power through the 7pin trailer connector, what are you using on the vehilce side of things? An isolator, selector? How long does it take to make a full charge on a deep cycle battery (ball park?)?

2. Mike, can you recharge off the vehicle battery in an emergency? I am not forseeing more than a 3-4 day self reliant trip with no services. Can your system hold a good charge that long? I am not trying to bring everything from the home with me on these trips, they are designed to get away from all the stuff, but the water pump, freezer fridge, and led lights are a non-negotiable to power up. Weekend long trips will be most typical.

Do you have a link to your charger?

3. Has anyone had great success/reliability with the newer solar chargers... I see some cheaper trickle chargers at the marine stores but I have to admit I am not an electric wizzard.

Thanks!

 

[spressomon]

Thanks guys, this is really giving me some good ideas.

I love the marine market, being a former Florida boy I am experienced in most things marine... and the marine market crosses over well into the off road enviroment.

Now, I have a few questions...

1. For you guys running power through the 7pin trailer connector, what are you using on the vehilce side of things? An isolator, selector? How long does it take to make a full charge on a deep cycle battery (ball park?)?

2. Mike, can you recharge off the vehicle battery in an emergency? I am not forseeing more than a 3-4 day self reliant trip with no services. Can your system hold a good charge that long? I am not trying to bring everything from the home with me on these trips, they are designed to get away from all the stuff, but the water pump, freezer fridge, and led lights are a non-negotiable to power up. Weekend long trips will be most typical.

Do you have a link to your charger?

3. Has anyone had great success/reliability with the newer solar chargers... I see some cheaper trickle chargers at the marine stores but I have to admit I am not an electric wizzard.

Thanks!

Well...not the best solution but I am just running a charge from the alternator to the 2-Lifeline's in the trailer via the 7-pin. Originally I was going to utilize a Honda or Yamaha generator to recharge but since the wifey doesn't come along (you can guess who was going to be the power hungery user ;-) ) my 2-Lifelines are basically overkill for how/where I use my trailer.

I already run two batteries on the rig with the Powergate isolator. Just wasn't up for setting up yet another (third) circuit on the rig for the trailer with yet another isolator...given the fact that the batteries never see a real load when I'm out exploring.

 

[Rezarf <><]

So when using a 7 pin trailer hook-up you simply install an in-line isolator and charge it off the alternator right?

What is involved in addition to the isolator? Is it a simple wire to the hitch plug and on to the battery? What about charging management, could you over power the battery?

Sorry total newbie here.

Thanks in advance.

 

[Mike S]

Thanks guys, this is really giving me some good ideas.

I love the marine market, being a former Florida boy I am experienced in most things marine... and the marine market crosses over well into the off road enviroment.

Now, I have a few questions...

2. Mike, can you recharge off the vehicle battery in an emergency? I am not forseeing more than a 3-4 day self reliant trip with no services. Can your system hold a good charge that long? I am not trying to bring everything from the home with me on these trips, they are designed to get away from all the stuff, but the water pump, freezer fridge, and led lights are a non-negotiable to power up. Weekend long trips will be most typical.

Do you have a link to your charger?
!

Drew

I have two 105 AH batteries. Combined, they provide 210 AH (give or take). I use these for running accessories, but not power tools, winches or inverters. Consequently, they last a long time. LED lights and water pump are nothing. The fridge will draw more amps. Get the data on the draw on the fridge and decide what you need for the average trip.

In my truck, the starting battery is inviolate. I do not use it for anything but starting. said another way, I will not use the starting battery to keep the beer cold.

In a pinch, I could move the starting battery (group 31 Optima Yellowtop) to the trailer and use it, but hooking it to another discharged battery will simply result in two sub-parr batteries. The more likely scenariois that I have a problem with the starting battery, and jump form the trailer batts.

The charger I have is made by Guest. It is designed to intelligently charge and maintain a pair of batteries (two banks) in a boat. I do not remember the model name, but West Marine sells them for about $150 to $200 - less than a quality isolator, and I can leave it plugged in 7 X 24. My batteries are over four years old, and when I checked them today, they were just fine. If you think about it, you will realize that your trailer spends a lot more time parked than running behind your truck. This was the basis of my decision to go with the set-up I have. however, you COULD set it up so that the batts charge off both the vehicle and the 100V charger. You would b=need an isolator. The iring diagrams for this set up are available IIRC.

I have had the trailer in the field for trips of three weeks or more, and never run out of battery. But it could happen, and I'd be down to manual processes. Not a big hardship.

Mike

 

[Martyn]

Drew

The wire back to the trailer is usually 10 gauge fused. Due to the gauge it doesn't allow for a full "alternator" charge but it will charge the battery in the trailer after a reasonable amount of time.

If you install two batteries in the trailer connect them together using 6 gauge otherwise you will have uneven charging and discharge between them.

The trick seems to be starting out with fully charged batteries. We typically install a "Power Tender" smart charger http://www.adventuretrailers.com/12volt_solar.html. It works as a trickle charger or as a full 6 amp charger. The "smart" part is it knows when to switch from one to the other. We install these units along with a marine grade shore power socket to connect up to 110 volt.

The simplest way to stop draining the trailer battery with the vehicle, or the vehicle battery with the trailer is to disconnect the trailer plug when you stop for any length of time. There is lots of fancy gadgetry out there you can use, but unplugging is the simplest. Either your plugged in or your not!

 

[Rezarf <><]

Thanks Mike and Martyn-

Martyn-

Do you guys run the 10 gauge wire from the front to the trailer and also run the plug in for 110v hook up. Or is it a stand alone system and must be plugged into the 110v and charged up before leaving out on a trip?

I am thinking a combo of the two may be the best setup.

Thanks again guys.

 

[Rezarf <><]

Thanks Mike and Martyn-

Martyn-

Do you guys run the 10 gauge wire from the front to the trailer and also run the plug in for 110v hook up. Or is it a stand alone system and must be plugged into the 110v and charged up before leaving out on a trip?

I am thinking a combo of the two may be the best setup.

Thanks again guys.