how long should a battery last after charge

[Fishnblood]

Hey guys, when I have my wheelhouse plugged in my battery charges just fine (I think). But tonight I decided to fire up the heater and make sure my battery held a charge, it did but only for an hour. I had it plugged in for 2 days. The battery is a new marine battery that I just got this past summer. This doesn't seem normal, I thought it should be more along the lines of 1-2days? also, my heater is only getting to 65 degrees (could this be due to the battery getting low?)

Any input would be appreciated. Thanks

[Whoaru99]

Without knowing how much current in being drawn from the battery it's impossible to know how long you'd expect it to hold up.

I agree one hour doesn't seem right though.

Have you checked the electrolyte level in the battery to be sure it's not low (assuming it's not a sealed battery)?

[bobbymalone]

I'm guessing that's a marine deep cycle and not a marine starting battery?

[otterman91105]

I get about 2 days out of my battery and it's just a normal deep cycle battery.

[tonkapat]

What kind of charger? What kind of heater?

My guess is bad or cheap charger that took out the battery

[Boar]

I think deep cycles should chaged on trickle charge if you had it on regular charge u could fried the batterie.

[Whoaru99]

Deep cycle batteries are routinely charged at much more than a trickle rate (such as by virtually all on-board chargers in boating applications).

[Boar]

Right but being on a shop type cgarger to long, cant that damage the batterie?

[Whoaru99]

Most chargers these days are automatic. So, no, I don't believe it's likely the battery would be damaged by connection for two days...even assuming that a shop-type charger was used.

I think the first thing to be done is check the electrolyte level in the battery if it has removable caps.

[Wanderer]

Yes, you can damage your batteries by overcharging them. A shop type charger for standard cranking batteries can charge at 40 amps - 50 amps for jump starts.

Your marine deep cycle batteries should be charged at 10 amps. Depending on the amount of charge left in your battery, you should re-charge it either for a particular amount of time to restore it, or the best way is to use an automatic charger that shuts off when a full charge is achieved.

I believe the OP has either:

A bad battery

A cranking battery instead of deep cycle

A bad charger

A short in his trailer or heater that has a constant draw on the battery.

I would pursue a remedy by:

1. Determine your type of battery and the Amp hour rating (more is better)

2. Get the battery tested.

3. Buy a tester for your home use to determine the charge in your batteries before re-charging. Don't charge for 8 hours when 4 will do.

4. Test your charger. You can do this by simply charging for a couple hours and re-check with the battery with your tester to see if it gained. You should let the battery sit off the charger for 12 hours or so before checking.

If all that checks out OK, get your trailer tested for a short.

Good luck

[Whoaru99]

The type of battery dictates the charge rate it can accept.

For standard flooded cell batteries (which can include both starting and "deep cycle" batteries) rates 25% of capacity aren't an issue at all. IOW, if you have a 100Ah battery, a 25A charge rate isn't a problem. Gels can accept around 30%, and AGMs around 40% of capacity.

I'm not advocating those charge rates just illustrating that you can hit them pretty good with little risk of damage. A good all around charge rate is C/10, or 1/10 of the battery Ah capacity. C/10 charge rate of a 100Ah battery would be 10A.

So, unless you're using a manual fleet type of "shop charger" (where did the "shop charger" assumption come from anyway?) it's quite unlikely you're going to damage the battery by charging.

Far and away more battery damage is caused by not charging.

[Wanderer]

The shop type charger and over charging question came from boar. I have several chargers and one is what I would consider a shop charger that wheels around and charges at 40 amps plus jump starts. I wouldn't charge my deep cycles with it.

Right but being on a shop type cgarger to long, cant that damage the batterie?

Whouru, you seem to know batteries pretty well.

[LunkerCity]

Definitely check the charger! I almost bought a new vex battery when I thought both mine were fried. When I checked the charger, I realized the problem and saved some ching.

[Boar]

This is good stuff, I shlould have been more specific on the type of charger, I was refering to those 10/2 amp battery chargers you by at any retail store.

[grasshopper]

I have the same battery.Ran my TV and dishnetwork reciever for 10 hours and still had 65 percent charge in it.

[Wanderer]

also, my heater is only getting to 65 degrees (could this be due to the battery getting low?)

Any input would be appreciated. Thanks

Have you checked your air flow? Got any mouse evidence around? Check for nests.

[Fishnblood]

Sorry guys, i'm normally on here daily then the one day I don't come on I have 15 replies! Nice....Anyways here is the deal. I have a 2013 Ice Castle RV Edition that has a built in charger. I read up a bit on it and I believe the charger that is built in is a trickle charge? So if I understand correctly (which very well could be wrong) if my battery was drained and I plugged it in, maybe it doesn't always charge it back to a full charge just enough to get by? The battery is a Marine Deep Cycle battery and my heater is the stock either 18k or 20k BTU heater that comes in the Ice Castle. Let me know what you guys think. Also, I appreciate the wealth of knowledge around batteries it will definitely come in handy down the road.

[shizzy]

if it's a "battery tender" type then no, if the battery is fully drained, I doubt it would bring it up to a full charge in a day or so.

what are the specs on the charger?

[tonkapat]

do yourself a favor and go and buy an onboard charger with at least 10 amps per bank. Stay away from pro mariner chargers. I would do this soon before you wreck anymore batteries.

[Whoaru99]

I have a 2013 Ice Castle RV Edition that has a built in charger. I read up a bit on it and I believe the charger that is built in is a trickle charge? So if I understand correctly (which very well could be wrong) if my battery was drained and I plugged it in, maybe it doesn't always charge it back to a full charge just enough to get by?

I suggest finding out for sure what the charging capacity is then decide if you need to get something different/faster charge for your pattern of use.

It is very hard on lead acid type batteries to only charge them enough to get by. Batteries should always be fully recharged as soon as possible after every use to get the longest service life.