camper trailer battery help

[whiteknight]

Am looking at putting a battery on the camper trailer just to run flouro lights of at nightime. We dont go camping that often so i wasnt going to go to the trouble of hooking it up to the vehciles charge, what I want to do is just trickle charge it at home before we head out each time.

What type of battery should I bee looking for and how long would it run say 2 or 3 12v fluoro lights (just he ones from Supercheap).

Is this viable or is the battery life going to be shortened considerably? am I better off just grabbing a battery for $15 from the wreckers each time i want to head out for a few days and then disposing of it when we return home?

[spannercrab]

Say 3 x fluros @ 1A ea (maybe ... maybe .5A each depending on the type?)

So say an average of 3A x 4hr / night = 12AH / Day

So ... say a 3 night stay = 36Ah @ 12v which is quite a small battery really - about 1/2 the size of a standard N70ZZ type.

[-Scott-]

Say 3 x fluros @ 1A ea (maybe ... maybe .5A each depending on the type?)

So say an average of 3A x 4hr / night = 12AH / Day

So ... say a 3 night stay = 36Ah @ 12v which is quite a small battery really - about 1/2 the size of a standard N70ZZ type.

Yep - all sounds fair to me.

If you decide to go a starting battery rather than deep cycle, a larger battery will survive more cycles, because each discharge won't be as "deep." For example, a 40Ah battery won't enjoy a 36Ah discharge as much as a 70Ah battery will.

I'd avoid $15 wrecker batteries - if it doesn't have enough capacity, you won't know until too late.

Scott

[whiteknight]

So if I just get a starting battery it will last a 3 or 4 night stay no problems and then i throw it on the trickle charge when i get home or should I leave it sit half discharged and trickle charge it a few days before I am heading out next time?

Just not sure on the best way to store a battery for few months while not using it.

[-Scott-]

I'm not sure either. Unless you've got a very good charger you shouldn't leave your battery on charge for extended periods. Your average trickle charger isn't that good. I read recently that even a properly regulated "float" charger isn't good for a battery long term - something to do with sulphation of plates?

I'd charge it when you get home, but then take it off charge once it's full. Then periodically (once a month) put it back on charge to "top it up."

If you want to get really fancy, hook your camplights up for a day or so (your 3 x 4 hours, or whatever you reckon is equivalent to your weekend away) and recharge again, a week or so before you go away. That way you'll find out if your battery is stuffed, before it's too late.

I love my dual battery system - it means I don't need to worry about this stuff.

Scott

[gecko270]

Your best bet for a camper trailer ect is a deep cycle sealed lead acid battery. Go for something in the order of 600CCA. That should last you no worries. The problem with automotive batteries is that they are designed for starting where they take a massive kick in the guts from the starter motor. They aren't really fond of small loads for extended periods of time. You'll tend to find the battery won't last too long.

Deep cycle on the other hand are designed to handle smaller loads for longer. They also like to be left on trickle charge too. Get yourself a small solar panel to hook up to the battery during the day and then drain it a night. No drama's. The battery should last longer for the cost of them these days.

Don't bother with the wreckers batteries. After a large impact you'll usually find that a cell or two is damaged. It may just be a crack in the cell but you'll find that the battery even after being charged will only float at 12 or so volts. In other words its stuffed.

[murcod]

You can buy new starter batteries (calcium maintenance free) for around $70 - $80 with three year warrantys now. Dedicated deep cycle batteries cost big $$$ in comparison. Just don't tell the seller you've been using it for camp lights if you ever have to claim (they usually reduce the warranty for deep cycle use.)

You'll find a RC value on new starter batteries, this can be used to calculate the Amp/ hour rate of a starter battery. Use Google and you'll find the relevant formula.

Never leave a battery discharged for any period of time, that's when the most damage is done from sulphur building up. Also, never flatten one completely- I think around 10.7V is as far as you should discharge even a deep cycle? Once again Google has lots of info.