Boiling Battery!

[A S R]

Well I’ve been a very lucky boy! I’ve had a smell in my van lately that I thought was a stale water type smell so I bought a big bottle of Tank Fresh and poured it down the 4 plug holes. Sorted, I thought. Nope. When I got into my van last night it was worse than ever! I was sitting there puzzling over what else it could be when it came to me that knackered batteries can produce a smell too.
I have 4 leisure batteries on my van and right underneath where the smell seemed to be. The penny dropped!
So, at 11pm last night I opened one of my underfloor lockers where 2 of the batteries are and had a look / feel of them. Nope, they’re fine, no noise or heat. I then looked across to the other side of the van to where the other two batteries are ( with my head torch ) and I could see fumes and hear bubbling! . Panic mode rapidly engaged and I unplugged the mains socket from the wall. I then went round to the other side of the van and opened the locker door to be greeted by a horrible smell and a red hot battery bubbling away spitting acid out of the “ overflow “ hole at the top! Shit!
I had to get the pair of batteries out ASAP so shot off to get my tools. First job was to disconnect the batteries but could only get to the positive terminals so did them first. I then went to undo the battery clamp on the bottom so I could slide the batteries out and disconnec the negative terminals. Nope! The clamp nuts had rusted solid! There was no way they were com undone! Arse! A bit of brute force ensued and I rammed the first battery upwards breaking it free of the clamp. Then I could get at the problem battery. I had to go and get some thick gloves because the boiling battery was red hot! I quickly removed the negative terminal and humped it out onto the floor still boiling and spitting acid out. Nice.
So, my question is, is this just a naff old battery that’s given up or do I need to look elsewhere for another problem? The problem battery is number 3 in line out of 4. The other 3 batteries seem to be fine. I will be changing the pair on the one side because they are the same age though. I was due to be going to wales on my motorbike camping this week but because of the rain I hadn’t gone. I’m blooming glad about that now!
If anyone has any suggestions as to things I should be checking then shout up please.

 

[tacr2man]

Normally boiling and overheating comes about when overcharging eg when regulator fails on an alternator . But seeing as this is no 3 in 4 batteries it sounds as if the battery has failed . HTSH

 

[Brains]

Depending on age, I'd be inclined to replace the lot !

If one has gone, if they were all installed at the same time, then the others could follow.
(As a minimum I'd replace in pairs).

Do you really need 4 x leisure batteries ?
One or two is normal. But if you need four, then I'd be seriously looking at a single large lithium battery, basically half of the weight and size for double the power (and triple the price)
I'd also look at a solar panel with a battery master and see if it makes financial sense.

 

[Jev88]

So glad you are safe but you would have been safer to disconnect, ventilate and wait an hour or two for heat to reduce and gases to disperse. Taking the terminals off the battery can produce a spark and then the hydrogen sulphide(?) can ignite. Also violently shaking the battery when removing can be dangerous too. I am not criticising you but take care if it ever happens again.

Where possible I also run a pipe from the battery expansion ports and direct it to the floor under the van. At least the corrosive spitting isn't going inside the van?

I also think you will need to bin all 4 batteries as you ideally don't want to mix and match and a new battery can be "pulled down" by a faulty neighbour. You do need to have the voltage being supplied checked though so you don't waste good money boiling the replacement battery. I have 3 x Wet acid batteries and will replace with a single large LIPO soon.

 

[stevewagner]

Are you leaving them on charge all the time?

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[Swifter]

After that experience will you purchase lead acid chemistry again or move to lithium ?

 

[pappajohn]

Should have disconnected hookup and waited until cold.
A spark from disconnecting the battery could have ignited the hydrogen sulphide gas.....BOOM.
Acid and flying bits of battery take no prisoners.

 

[Richard n Ann]

Sounds like a shorted cell, If you measure the voltage on the hot battery it will probably be 10 something volts.

I connect up a small 0.8 amp maintainer on ours that isn't powerful enough to get anything hot under fault conditions.

 

[Pausim]

But if you need four, then I'd be seriously looking at a single large lithium battery, basically half of the weight and size for double the power (and triple the price)

Safer too.

 

[bobandjanie]

Just remember if you smell rotten eggs check your batteries. Bob.

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[A S R]

Depending on age, I'd be inclined to replace the lot !

If one has gone, if they were all installed at the same time, then the others could follow.
(As a minimum I'd replace in pairs).

Do you really need 4 x leisure batteries ?
One or two is normal. But if you need four, then I'd be seriously looking at a single large lithium battery, basically half of the weight and size for double the power (and triple the price)
I'd also look at a solar panel with a battery master and see if it makes financial sense.

The two I removed were on the van when I bought it over 5 years ago. The other two were only put on last year by a fully qualified auto electrician who has his own large very reputable business. I do a lot of wild camping for days sometimes weeks at a time so more the better. There are two separate MPPT solar systems feeding them constantly. I’ve looked at getting lithium but at nearly £2k for what I want it can wait a bit longer. I should’ve checked / changed the older batteries before now but never got round to it! Very nearly at great cost! I shall be keeping a very close eye on them from now on!

 

[A S R]

Normally boiling and overheating comes about when overcharging eg when regulator fails on an alternator . But seeing as this is no 3 in 4 batteries it sounds as if the battery has failed . HTSH

Yeah, definitely seems like a failure in the one battery. The other one I removed is still measuring 12.6v. It WONT be going back on though!

 

[A S R]

Are you leaving them on charge all the time?

No, only plug the van in occasionally to keep everything topped up so to speak. It’s off more than on.

 

[A S R]

Sounds like a shorted cell, If you measure the voltage on the hot battery it will probably be 10 something volts.

I connect up a small 0.8 amp maintainer on ours that isn't powerful enough to get anything hot under fault conditions.

The “ good “ one of the pair I removed last night is still registering 12.6v. The “ knackered “ one is measuring 6.4v. Definitely a failure in the one battery. They were the original pair of batteries that came with the van when I bought it over 5 years ago. The production date on the batteries is 12/16 so nearly 7 years old. New ones arriving tomorrow.

 

[A S R]

A nice shiny new pair of 100ah batteries now ready to go on! 4 year guarantee with these too but I’ll be keeping a very close eye on them.
Now the fun begins trying to fit them and wire them up at the same time into a locker only a few inches taller than the batteries!

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[Swifter]

A nice shiny new pair of 100ah batteries now ready to go on! 4 year guarantee with these too but I’ll be keeping a very close eye on them.
Now the fun begins trying to fit them and wire them up at the same time into a locker only a few inches taller than the batteries! View attachment 678961

How much did you pay for the 2 ?

 

[A S R]

How much did you pay for the 2 ?

£247.48 for the pair from Tanya Batteries. That was with next day delivery though. Brilliant service from Tanya and Yodel. I could’ve got slightly cheaper ones but these had to be millimetre perfect to fit in to the locker. I have to pull the rubber door seal off to let them drop into the locker then put the seal back on. They are an absolute perfect fit. Oh, and these have a 4 year warranty, the cheaper ones only had a 2 year one.

 

[BDM]

Another £100 or so and you could have got a 100 Ah Lithium.....

 

[Swifter]

Another £100 or so and you could have got a 100 Ah Lithium.....

Exactly what I was thinking .
Less weight, less space and same amount of usable amp hours !

 

[A S R]

Another £100 or so and you could have got a 100 Ah Lithium.....

Yeah, for 1 battery. This was for a pair of 100ah ones.

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[TerryL]

But am I wrong in thinking you don't (can't) just replace lead acid with lithium directly? Especially as there are two perfectly good lead acid batteries being retained? Don't you have to change other electrical gubbins in the system?
Sorry, bit of a numpty when trying to understand batteries - which is why I've stuck to a pair of good old-fashioned lead/acid that have served me faithfully without problem for years.

 

[Richard n Ann]

Yeah, for 1 battery. This was for a pair of 100ah ones.

Same usable capacity though because you can only discharge standard lead acid type to 50% without shortening their life.

 

[Swifter]

Yeah, for 1 battery. This was for a pair of 100ah ones.

You can’t use the full 200ah only 50% so that’s 100ah , the same as the lithium that would have been about £100 more . You would have less weight and more spare space . Each to their own .

 

[A S R]

But am I wrong in thinking you don't (can't) just replace lead acid with lithium directly? Especially as there are two perfectly good lead acid batteries being retained? Don't you have to change other electrical gubbins in the system?
Sorry, bit of a numpty when trying to understand batteries - which is why I've stuck to a pair of good old-fashioned lead/acid that have served me faithfully without problem for years.

This is my thinking too. To get the same 400ah in lithium would be a stupid price to pay! Even if they are smaller and lighter. I’m happy with the ones I have so what’s the problem?
You could say I could pay a bit more and get a smaller faster car. Why? I’m happy with what I have.

 

[A S R]

You can’t use the full 200ah only 50% so that’s 100ah , the same as the lithium that would have been about £100 more . You would have less weight and more spare space . Each to their own .

So going on your thinking to get the 400ah ( 200 usable ) I’d have to buy 2 lithium batteries at a cost of around £700 or so. Plus change the battery charger and any leads etc just to get to where I was / am by putting 2 lead acid / calcium ones on for £250. Ok. Not my sort of logic but each to their own as you say!

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[Old Gibber]

Same usable capacity though because you can only discharge standard lead acid type to 50% without shortening their life.

This is a rather dodgy statistic touted on lithium battery adverts. ALL batteries have their lives shortened the deeper you discharge them, including lithium.

You need to look at this statistic in a great deal more detail to get an accurate picture. Discharging every time down to 20% charge remaining will halve the life of the battery compared to discharging down to 50%. BUT, and it is a very big but, how often would you discharge down to 20% remaining? Probably not very often, so the useful life is not significantly reduced.

Even if you did discharge down to 20%, that should give 500 cycles. Supposing you use the van for 100 days a year off grid and discharge to this level, you would have a 5 year battery life.

By my way of thinking, when you also include price into the equation, lithium has just two advantages, weight, and a higher current discharge and recharge level.