Minimal battery just for lift
 

What is the battery needs just for the lift?

I plan to have completely separate batteries for the coach than the hydraulic pump. I assume a cranking battery is better than a deep cell battery for the pump? Will a small lawnmower batter be sufficient to raise the roof twice?

Thinking small for weight and for quicker charging and of course cheaper to replace down the road.

I have read between 75 and 150 cc amps for the lift

I'm just going to give you an opinion here, and it's worth what you're paying for it - but it may give you something else to think about.

I suspect the lawnmower battery may well have enough current output to lift the top twice, before being recharged, and I think an auto battery would certainly have enough output. But, and this is my concern - I don't think either are designed for the kind of deep discharge you will be putting on them and I would think they will fail to accept and hold a charge more quickly than a standard deep discharge battery. With that in mind, using one could possibly end up costing more in the long run. Both of these batteries are designed to be recharged immediately after the starting duty they are put to.

- Jack

I have a battery on mower, so might give it a shot… unless anyone has actually tried it already

If you ONLY use the battery for lifting (and not for ANY steady-drains, like the inverter or lights), a starting battery should be ok. This is afterall a starting circuit, with a starter-type motor. Until the 90’s it wasn’t unusual to run a starter for 20-30 seconds to geta. Car to start.

Whether the lawnmower battery has sufficient capacity is another question. You could try to see how many lifts you get from a single charge...but keep in mind doing so will damage the battery. In my experience, discharging a starter battery one time reduces it’s lifespan about 1/3 (no hard facts on this, just observation from the many, many batteries I’ve replaced in the shop - kill it once and you’ll be back within the year for a new one).

Is there any other reason besides the ones you listed above why you are thinking of going to such a small battery?

I would think a group 24 size would be the smallest that would give you good life and good service. Remember you are not carrying this on your back and the little weight saving you gain is going to be small in the grand scope of things. Also don't waste your money on a starting battery when you need a deep cycle battery.

I agree! Why spend the money for a battery that may prove inadequate when you can get a better one for a few dollars more.

Solely for weight, and to save that hanging box the stress.
All the battery will ever do the rest of its life is run the hydraulic pump. The camper has dedicated batteries for power separate from the pump batt, and the pump is basically a starter motor, so a starting battery makes the same sense as the starting battery under the vehicle hood…
I still may try it just to see what happens, I have a batt in the mower I can play with.

Good try it and give us you feed back and experience.

What battery will your emergency breakaway switch be connected to? You need to have that, and it will require a well charged battery to apply the brakes reliably.

I think it's a good idea. Let us know/give us a update!

Typically break-aways have their own small battery that is charged through the brake circuit. Is this not the case on the HiLo?

NO, the break-away on the HiLo and all the other RV trailers I have owned come off the main battery. The small battery you are talking about would be on a utility trailer with brakes that does not have the larger battery and electrical system that RVs have.

Hmm. Neat. Not the way id design it!

Good info.

Knotty, my Sister's horse trailer has a small battery that powers her breakaway system. I don't think there is any other electrical system in the trailer other than the running lights that are powered off the truck.

My breakaway in my HiLo comes directly from the battery.

- Jack

That makes sense Jack.

I get why RV/TT makers would do it that way. Just not how *I* would do it.

I used to be one of those guys who would try to integrate everything. Anymore I prefer independent systems. Not everything fails together, easier to t-shoot or modify.

Having an independent breakaway system, in particular, seems like a better approach. RV batteries are always problematic-see the posts around here!

Anyway, thanks for clarifying. As I don't own a HiLo (yet), I didn't realize they were integrated. My last 2 TT's they were independent.

Trailer makers use the main battery because it's cheaper for them. It doesn't necessarily make good sense.