Holy Bubbling Batteries.

OuterBombie

Howdy,

So last week I got my van out of what turns out to be a long winter storage (another story).

I noted that the leisure batteries were running very low so this weekend I plugged it in for the weekend.

On Sunday morning I awoke to the sound of the carbon monoxide alarm going off outside in the van, went out, opened all windows etc, alarm goes off. Hmmm, very strange as gas all off. I disconnected the gas bottle and closed it up again. 30 minutes later, same thing, except this time I noted a strange, sewage type smell on entering the van. Ok, maybe something in the grey tank so I put water with bleach down all the drains. 30 minutes later, same thing.

Totally stumped I was sitting in the back of the van and heard a slight gurgling noise, opening the press where the second leisure battery was and spotted some fumes coming out of the battery and the battery itself feeling pretty warm. Crap, ok, electricity off. leave it to settle.

Before the winter I had a split charge relay fitted to the van which should isolate the cab battery from my two leisure batteries (had problems with the cab battery dying).

This would have been the first decent charge since then, and maybe in 3 months.

Could it be that the leisure battery is just gimped?

Or, hopefully not, could my charger not be working right.

I plan to disconnect the battery this evening after work.

Any thoughts on what I need to check, maybe just need a new battery?

Pretty glad this didn't happen while on hols with the family

OB.

sparkyjc

Be very carefull here. Your battery has shorted out ie.. your positive and negative poles are now the one. It may be cables reversed somewhere by mistake or an unfused positive wire has welded to the body (which is your negative) somewhere on the van. This is a very dangerous situation. It is a potential bomb as it will create a very ugly explosion. The bubbling you hear is the acid boiling in the battery. You have already seen the acid fumes. This must be rectified and the battery disconnected. If your battery stopped bubbling when you unplugged your mains lead then disconnect the leads at the terminals and get a competent person to check it. A simple wiring problem will be causing this to happen.

moodrater

Our neighbour just burned down his house charging a dead battery in his caravan yesterday. In general if you leave a lead acid battery in an uncharged state its scrap within a few weeks. I'm guessing this was not an agm battery.

Sewage smell is H2S hydrogen sulphide otherwise knows as stink bomb very nasty stuff. I have personally witnessed a large yuasa battery explode in an electronics factory having been left of fast charge for 24 hours instead of 5hours. I was about 25 feet away and what can be best described as a shockwave of vapour passed me so count yourself lucky.

Your charger must have been well above the gassing voltage for the battery I wouldn't trust that one again.

OuterBombie

moodrater wrote: »

Our neighbour just burned down his house charging a dead battery in his caravan yesterday. In general if you leave a lead acid battery in an uncharged state its scrap within a few weeks. I'm guessing this was not an agm battery.

Jaysus.

moodrater wrote: »

Your charger must have been well above the gassing voltage for the battery I wouldn't trust that one again.

Trust the battery or the charger? I figured the battery is probably dead after that anyhow. Thanks.

OuterBombie

sparkyjc wrote: »

If your battery stopped bubbling when you unplugged your mains lead then disconnect the leads at the terminals and get a competent person to check it. A simple wiring problem will be causing this to happen.

Will do, thanks.

OuterBombie

Hi Lads,

Long day at work so I didn't get out to my van until late yesterday evening. It had been off the mains since Sunday and after our discussions yesterday I was worried should I also have disconnected it on Sunday.

First up, the bubbling battery looks ok, I took its voltage which about 12.5V which reads ok on this chart:



I have two leisure batteries attached, one up in the living area (which was bubbling) and one underneath in the "boot". The underneath one was also reading 12.5V.

I turned on the switch at the control box and all lights, electric items worked ok.

I then plugged the van into the mains again, and re-read the voltage. Both batteries got up to about 14.4V, which I think is ok for charging. Nothing abnormal occured although I didn't leave it on for long.

Initially I was expecting one or two things, one, the battery is gimped so a low voltage reading in situ (which is not the case 12.5V). Two, that the charger is maybe overcharging the battery, but I think 14V would be pretty standard.

Sparkyjc, you mentioned "It may be cables reversed somewhere by mistake or an unfused positive wire has welded to the body (which is your negative) somewhere on the van." Would I not see that with a voltmeter across the connections? Also would the battery not work if that was the case, if it shorted out?

Thanks.

sparkyjc

If your voltage is 12.5 there probably isn't a leakage to earth. You are probably suffering an overcharging problem possibly because of a voltage regulating problem or a dead cell in your battery. How are your two leisure batteries connected together if they are a distance apart. It would be more suitable if they were batteries of the same type from the same shelf.Your charging voltage seems fine but may not be regulating properly.Have you a zig unit in the van. Are they proper leisure batteries suitable for constant charging and recharging. It is difficult to give proper advice without seeing your full system. A visit to an auto electrician would not be too expensive and would put your mind at ease.Certain checks could be done which to be honest are too difficult and dangerous to go through online second guessing a system. This happened once and more than likely will happen again.As i said before you are dealing with a potential bomb. Many mechanics or electricians have seen and heard horror stories as i have myself. Some simple problem is causing it. It will be rectified and you will be good to go. Happy camping.

OuterBombie

Thanks,

Obviously not treating the problem lightly, especially now after doing some research on batteries :eek:

The batteries are the same type and size (also same age) and are leisure batteries. The distance between them is less than 1 metre, its just one is down in the boot (with a pipe vent) and one is under a seat above the boot at back of van.

There is a charger but not sure is it a Zig unit and I agree it must not have been regulating correctly.

I have no intention of leaving the battery under the seat until I get some clarification on what's up with it. Just need to find an auto electrician here in Galway to get a look over it.

Thanks.

OB.

moodrater

OuterBombie wrote: »

Both batteries got up to about 14.4V, which I think is ok for charging.

Depending on battery type at 14.4V the battery could start gassing at 21-22 degrees celcius. Problem is as the battery takes a charge it heats up and the gassing voltage drops this problem is exacerbated by confined battery comparments such as under your seat. At 30C it would be gassing away goodo.

OuterBombie wrote: »

I have no intention of leaving the battery under the seat until I get some clarification on what's up with it. Just need to find an auto electrician here in Galway to get a look over it.

As sparky mentioned a shorted cell would cause this, a shorted cell effectively means that the 14.4v is divided accross 5 cells instead of 6 gives 2.88V per cell which is miles above the gassing voltage unless its well below 0C. Short can be temporary and caused by plate warping / exansion due to elevated temperatures.

What model is the zig most of that stuff is ancient technology for the price of an auto electrician you'd get a modern 3 stage charger.

OuterBombie wrote: »

its just one is down in the boot (with a pipe vent) and one is under a seat above the boot at back of van.

Sound to me like the one under the seat shouldn't be there.

niloc1951

There are a number of reasons why a battery will bubble, as opposed to the normal gassing during the charging cycle, none of them good.

The most important thing though is that the gas given off is HIGHLY EXPLOSIVE :eek: