Thermal Run Away

[eagle19952]

Can anyone explain this ?

It appears to be the same problem Clifford had...

[eagle19952]

well i guess it's all about battery bay temperature....

[gus]

Was any one of the batts shorted out, this will usually kill at least some of the others.

Happened to me with two start batts, shorted one killed the other.

[Brassman]

agm batteries? What's are the charging voltages?

[eagle19952]

these were not mine, just thought it was interesting, apparently it is more common than i realized...

[HB of CJ]

I am thing here a massive internal short out.  Perhaps bad factory batteries?  Yep ... sometimes you get a cascading effect.  Years ago I had a Nickel Cadmium 180 amp hr cell establish a very definite internal short.  Very spectacular to say the least.  Were the bad batts rated for a high vibration installation?

[Geoff]

I've had batteries swell up when they get old, apparently someone made these with plastic that would not expand so they just cracked under pressure.

--Geoff

[Jeremy]

I'm curious to know what the white substance is that's visible through that crack - is that rampant sulphation (which might well account for the swelling), or are these AGM batteries and that's the mat showing? If these were flooded batteries I'd hate to think where all that acid ended-up..

Jeremy

[luvrbus]

Mine the cases melted together I liked to never got them to come a part.It is more common than you think if you read the fine print the AGM's are the happiest at 77 degrees which is almost impossible to achieve in a RV application  

Those are not the sealed pressure regulated AGM batteries so venting and expansion should have not been the cause

[Iceni John]

If every battery were individually fused, such as with the Blue Sea battery-terminal fuses, would that help in this case or not?   If one battery catastrophically shorted out internally, how much current would the other batteries try to push into it?

I have 300A Class T catastrophe fuses on each battery bank's negative cable (per Sean Walsh's recommendations), plus fuses and circuit breakers on each load's positive cable, but nothing protecting each individual battery.

John