Lishen 272AH thread?

[cinergi]

How do we know this is the battery that started the fire? That's my question. Maybe the charger itself started the fire. There a lot of other components in there that could be at fault.

 

[DJSmiley]

Hard to check what has caused it.
In the previous installation pictures, I also saw the BMS leads below the busbars. It could be for example be caused by the BMS leads scrubbing against the busbar and causing a short. (Damaging the leads due to vibaration)

However it's hard to guess, and based on the damage, it's hard to even see what has started and what is damage caused by the fire.

From what I've seen in various youtube video's, it's very hard to get a LFP cell to actually start burning. So I doubt if the cells are the initial cause, or the cabling (The currents a cell can provide are enough to burn a wire, and that hot wire is capable of setting things in fire.)

Also, I don't have lishen cells yet, but how is the outer case? Is it directly connected to +? If so, damaged wrap can cause a short also.
Mine EVE cells did have + on the outer case, but I'm not sure if it's directly connected or only a leakage current (incapable of providing huge amps)

 

[stobbie]

No offense taken.. I saw that the bushbar on which I had the alligator clip of the charger has a different color from the other ones.
I think there has been a high resistance in the cheap chinese clip and that it has heated up and maybe melted one of the balancing wires of the BMS and caused a short circuit or something.

 

[stobbie]

I don't think it was scrubbing of the wires, the van has been parked al month.
I was suspecting the chinese charger myself as wel, but the charger has the least fire damage of all, so I don't think it was.
I still will not rule out an internal fault in one of the cells, because it is very strange that only half of the pack burned down..

 

[Acho_303]

After seeing your post I watched a video where these firemen stress tested three different battery technology, Lifepo4 being one... and in their video over charging just caused the battery to bloat and spit out acid, I assume, or some kind of liquid, but it never caught on fire.

Not saying it isn't possible, just comparing...

 

[DJSmiley]

That's one of the video's I was referring to. That makes me think it was heat in a cable, caused by a short or somewhat.
Charger leads can, but I'm not sure if a few amps is enough to heat the wire to a point where it could initiate a fire

 

[cinergi]

After seeing your post I watched a video where these firemen stress tested three different battery technology, Lifepo4 being one... and in their video over charging just caused the battery to bloat and spit out acid, I assume, or some kind of liquid, but it never caught on fire.

Not saying it isn't possible, just comparing...

Just electrolyte (not acid). I'm not aware of any videos of LFP starting a fire.

 

[stobbie]

I'm sure it hasn't been caused by heat in a cable (except maybe the charger, charging at around 30amps). Every cable was fused, the charger as well.
4 of the cells have swollen like a balloon, one has burst open. I'll take photo's of the cells tomorrow.
The vents on top are still closed!! They obviously didn't do their job!

They can catch fire, but rarely:

 

[baipin]

Does anyone know if the Lishen 272 cells can be laid only upright on their base, on the long side, or the short side?

 

[michael d]

Overcharging causes heating within a cell and prolonged or extreme overcharging has the potential to cause a fire.

I don't know the specifics of how stobbie configured his system but as a general rule:
Most BMS modules are meant to be a last line of defense against over/under charging.
Typically charge control should be a separate dedicated function/system.
IE: Best not to depend on the BMS module to control charging.

Hard to do a postmortem on a pile of charcoal.
May never know the cause of his meltdown...

Stobbie did mention that he forgot to turn his charger off during top balance:

This post makes me wonder if perhaps he damaged one or more cells while top balancing.

IE: "I've done my charge at 50 amps, but forget to turn the carger off, so it kept on charging until amps dropped to zero, and it seems that one cell has developped a very very slight bulge, only a mm or so.."

Lishen 272AH thread?

I'm going to guess cutting off at 3 volts (as measure by a meter at the cell terminals, not at the cables or any other pieces of attached hardware) will net you about 5Ah less than actual capacity. So if you get 267, then I think you'd have a perfect 272Ah cell. Thanks. I'm hoping these test...

diysolarforum.com

In another post - I can't put my finger on it right now - but to summarize - I think he was having some issues with the busbars making good electrical contact. That could potentially result in the BMS not seeing the actual cell voltages.

I offer that comment as a possible justification for investing in good busbars. Personally I like the CALB busbars - five thin layers of flexible copper with an arch in the middle: https://amprevolt.com/collections/battery-accessories/products/prismatic-cell-lifepo4-busbar

Perhaps the moral of the story is - "A chain is only as strong as the weakest link" - and there are a lot of links in a DIY lion system...

I use an Electrodacus SBMS0 which stops the charging when any cell goes over a preset voltage(3.55 volts). it works with 12-volt up to 24-volt battery banks.
a loose connection can cause an arc-ing also.I have no experience with Victron stuff, but a lot of people seem to like it. perhaps you could get the state fire marshal to do an extensive investigation as to the cause of the fire or if you had insurance maybe your insurance man can help to send you to a route to determine the cause.
so sorry for your terrible loss.

 

[stobbie]

My cheap BMS has cell overvoltage protection as well. The camper was not insured unfortunately :-( ...

I'm trying to forget about my loss. Today, with a friend, we have taken most of the interior out of the camper. The structure is mostly intact. I think it can be repaired, but it will take time and cost a lot of money.
I think I'll buy another campervan and use that untill this one has been repaired and sell it again after.


I have used diy lifepo4 batteries for many years; in this campervan, in my Land Rover Defender, in my boat, at home for all kind of projects, built several for friends. But after this incident I have become a little affraid to use them again. Until a few months ago I had only used Winston cells, and they have always been flawless..

 

[cinergi]

I'm sure it hasn't been caused by heat in a cable (except maybe the charger, charging at around 30amps). Every cable was fused, the charger as well.
4 of the cells have swollen like a balloon, one has burst open. I'll take photo's of the cells tomorrow.
The vents on top are still closed!! They obviously didn't do their job!

They can catch fire, but rarely:

No, these didn't spontaneously catch fire. They put a heater on it AND a pilot light to make sure any gasses caught fire.

Can you SET LFP on fire? Yes. Will they spontaneously combust? No.

I'm relatively certain something other than your cells is responsible for the fire.

 

[Gazoo]

This post makes me wonder if perhaps he damaged one or more cells while top balancing.

IE: "I've done my charge at 50 amps, but forget to turn the carger off, so it kept on charging until amps dropped to zero, and it seems that one cell has developped a very very slight bulge, only a mm or so.."

I think we would have to know if the cells were overcharged and by how much. It is normal for EVE cells to expand and contract. I don't know what is normal for Lishen cells.

Also, I don't have lishen cells yet, but how is the outer case? Is it directly connected to +? If so, damaged wrap can cause a short also.
Mine EVE cells did have + on the outer case, but I'm not sure if it's directly connected or only a leakage current (incapable of providing huge amps)

Please take a look at my thread here if you haven't already done so.

The vents on top are still closed!! They obviously didn't do their job!

I have noticed severely bloated cells posted by other forum members and the vent did not function. I am not an expert as to what is supposed to happen to cause a cell to vent.

No, these didn't spontaneously catch fire. They put a heater on it AND a pilot light to make sure any gasses caught fire.

Can you SET LFP on fire? Yes. Will they spontaneously combust? No.

I'm relatively certain something other than your cells is responsible for the fire.

I agree but can't be 100% certain there was an internal failure of one of the cells. If there was, would the cell catch on fire? In any event I think it's very rare for a cell to fail internally...but not saying it can't happen.

Aside from that there are several things that could have happened. One possibility is the cells were overcharged, bloated and caused the terminals/busbars to fail which resulted in arcing. That in turn started a fire.

Since the cell bloated so badly I wonder if it's possible gasses were expelled from the cell, possibly through the terminals or through somewhere through the shell, and the result of arcing mixed in with the gasses started the fire. I am no expert on this and what happened here is terrible and we may never know. So I am just envisioning this in my head.

Prismatic cells are encased in an aluminum shell. I have often wondered how much they would have to heat up before they started on fire?

 

[Gazoo]

I'll take photo's of the cells tomorrow.

I know you are trying to forget about your loss and again I am so sorry this happened to you. But if you don't mind, please take photos of the cells at your leisure and anything in the surrounding area you think might have been the cause. While we may never know the events leading up to this, it does give me much to think about. Thank you.

 

[Acho_303]

On a side note, my batteries arrived at 3.24 and 3.25.. 25% charged.. Is there any concern there? What did everyone else batteries arrive at? I am going to allow them to warm up over the next few days before top balancing, but wonder about the soc and if thats okay

 

[Burke]

That's one of the video's I was referring to. That makes me think it was heat in a cable, caused by a short or somewhat.
Charger leads can, but I'm not sure if a few amps is enough to heat the wire to a point where it could initiate a fire

Could there have been a loose connection to a battery?

 

[Burke]

On a side note, my batteries arrived at 3.24 and 3.25.. 25% charged.. Is there any concern there? What did everyone else batteries arrive at? I am going to allow them to warm up over the next few days before top balancing, but wonder about the soc and if thats okay

Mine were mostly in the 15-25% range when they arrived, but some were higher, like 70 amp hours higher, which made balancing fun!

 

[cinergi]

I agree but can't be 100% certain there was an internal failure of one of the cells. If there was, would the cell catch on fire? In any event I think it's very rare for a cell to fail internally...but not saying it can't happen.

Thus far I've not seen any evidence of LFP spontaneously combusting even when physically damaged.

Aside from that there are several things that could have happened. One possibility is the cells were overcharged, bloated and caused the terminals/busbars to fail which resulted in arcing. That in turn started a fire.

Since the cell bloated so badly I wonder if it's possible gasses were expelled from the cell, possibly through the terminals or through somewhere through the shell, and the result of arcing mixed in with the gasses started the fire. I am no expert on this and what happened here is terrible and we may never know. So I am just envisioning this in my head.

Prismatic cells are encased in an aluminum shell. I have often wondered how much they would have to heat up before they started on fire?

WRT bloating -- that may have been caused *by* the fire. Everyone's focused on the cells as the starting point. It's statistically more likely it was something else.

We really have no idea what happened of course. I hope someday we do because I'm about to put 28kWh of this stuff into my new 5th wheel

 

[blutow]

Does anyone know if the Lishen 272 cells can be laid only upright on their base, on the long side, or the short side?

from the spec sheet:

c）During the course of storage or usage, keep the cells upright .

 

[baipin]

from the spec sheet:

c）During the course of storage or usage, keep the cells upright .

Thanks!