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House burned down

Just in case that link doesn't take you to the right place, this one has them upright.
I put their 1.1MWh mini container on my Santa list

 
I sent a message to Amy from her website inquiring about the boxes, and to see if they can be made to work with 230Ah EVE cells and JBD contactor BMS.
 
I know for sure that eel and seplos has 230ah boxes, with non stacked orientation

Call me weird but I don't want a Seplos BMS. I keep seeing where they mess with it and v3 is not as good, or something. I dunno.
Part of me wants to get JK BMSes, another part just wants to retain the JBDs I have (with 300A contactors LOL overkill) just because I own them already.

Maybe all it would take to make it "work" with 230Ah is to just put a spacer block in the back of the case to account for thickness difference. I should check cell dimensions.

I'll take my discussion to the Luyuan battery box thread as to not junk up this one with my ramblings and musings.
 
This is my summary of the fire. The Cells are arranged in 16s x 6 with fuses between each bank. After the fuses the banks are then connected together with a copper busbar. In order for one of the fuses to blow, then there would need to be current flow of in excess of 200 amps. The fuses were not type T fuses, so once the fuse melted then it continued to arc causing a fire.

The root cause would have to be one of the Cells that became shorted. That would drop the voltage down so that the current would flow from the other 5 banks to the bank with the defective Cell.

There was an indication of issues with the Cells from Xuba from the leaking Cells. The leaking Cells were replaced, but there were possibly others that just needed to have more time before they went.

The Cell that became shorted would have had to be a sudden event. The system had been working fine for years, and was working fine the day of the event. It wasn't until the sun had gone down and the system was in discharge mode, that the event occurred.

The system was put together in a meticulous manner and a lot of thought on safety was evident in the displayed results.

The Cells were all on a metal shelf and monitored, and still his house is destroyed.

This is all speculation, of course.

I believe that how we treat our Cells is very important. The Cells should be treated gently and not abused by excessive charging or discharging, above or below the knee.

Regular Cell monitoring and balancing should be a daily regime.

My thoughts are that LFP technology is still one of the safest Cell technologies that we have. This is evident in the direction of EV manufacturing. It also makes me question some of the Cells that do not make it to EV quality. Are we risking our homes to save a few bucks?

My conclusion is that the only way to be entirely safe is to remove the hazard from your home.
 
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The Cells were all in a metal box and monitored, and still his house is destroyed.
Where was this indicated? As @Mattb4 pointed out in a few messages above the shelf the batteries were on only shows the metal cross beams and legs left which seems to indicate there was very little metal supporting and surrounding the batteries.. i.e. most of the shelf was flammable. Would like confirmation of that. Even if batteries did catch fire there seems like there should be way to one, prevent it from spreading to other batteries/shelves and two, to not catch something flammable on fire outside of the immediate battery storage area.
 
One other interesting part is it appears the system used solid intercell busbars. If a cell became extremely bloated and eventually popped the pressure release cover it may have put a lot of pressure on the terminals of other cells. I would think then that it would always be best practice to use flexible busbars that could help prevent putting excessive pressure on other cell terminals during a catastrophic cell failure event. Not saying this is directly related to this fire but it does make sense that this would provide extra safety insurance to use flexible busbars.
 
Where was this indicated? As @Mattb4 pointed out in a few messages above the shelf the batteries were on only shows the metal cross beams and legs left which seems to indicate there was very little metal supporting and surrounding the batteries.. i.e. most of the shelf was flammable. Would like confirmation of that. Even if batteries did catch fire there seems like there should be way to one, prevent it from spreading to other batteries/shelves and two, to not catch something flammable on fire outside of the immediate battery storage area.
My apologies it should read a metal shelf, not a metal box. I will edit it.
 
Where was this indicated? As @Mattb4 pointed out in a few messages above the shelf the batteries were on only shows the metal cross beams and legs left which seems to indicate there was very little metal supporting and surrounding the batteries.. i.e. most of the shelf was flammable. Would like confirmation of that. Even if batteries did catch fire there seems like there should be way to one, prevent it from spreading to other batteries/shelves and two, to not catch something flammable on fire outside of the immediate battery storage area.
The official report from the fire inspector was not an issue with the Cells catching fire but it was the fuse arcing that created the fire. If a Cell shorted then I am hoping that it does not catch on fire. Is there any evidence that LFP cells catch fire? I watched the video on one guy puncturing a Cell with a spear and the result was flames after he punctured it several times. But has a LFP cell ever caught on fire without being abused?

If we cannot trust the LFP Cells to not spontaneously combust then all of us are in serious trouble.
 
The official report from the fire inspector was not an issue with the Cells catching fire but it was the fuse arcing that created the fire. If a Cell shorted then I am hoping that it does not catch on fire. Is there any evidence that LFP cells catch fire? I watched the video on one guy puncturing a Cell with a spear and the result was flames after he punctured it several times. But has a LFP cell ever caught on fire without being abused?

If we cannot trust the LFP Cells to not spontaneously combust then all of us are in serious trouble.
Right but the root cause that made the fuse blow in the first place is what everyone is interested in. To sustain an arc there needs to be high current flow, not just normal use. Where was all the current going and why?
 
The official report from the fire inspector was not an issue with the Cells catching fire but it was the fuse arcing that created the fire. If a Cell shorted then I am hoping that it does not catch on fire. Is there any evidence that LFP cells catch fire? I watched the video on one guy puncturing a Cell with a spear and the result was flames after he punctured it several times. But has a LFP cell ever caught on fire without being abused?

If we cannot trust the LFP Cells to not spontaneously combust then all of us are in serious trouble.
I have heavily abused my CALB plastic cased lfp cells, charging them when frozen, discharging them well below cut-off, charging them to 4v on occasion. They puffed up and failed, but they did not catch fire on me.
 
Right but the root cause that made the fuse blow in the first place is what everyone is interested in. To sustain an arc there needs to be high current flow, not just normal use. Where was all the current going and why?
Into a failed pack….. parallel packs always need inter-pack fusing, with stuff that won’t catch fire. We were discusssing this 15+yrs ago on the outback power forum when I was messing with wet Nicad…
 
I guess for my own ability to be able to sleep and not be concerned about the LFP Cells catching the house on fire, I would hope to believe that with OP's setup then if he would have used the class T fuses, then the fuse would have opened and that would be the end of the story.
 
I guess for my own ability to be able to sleep and not be concerned about the LFP Cells catching the house on fire, I would hope to believe that with OP's setup then if he would have used the class T fuses, then the fuse would have opened and that would be the end of the story.
In my opinion, yes….
 
Right but the root cause that made the fuse blow in the first place is what everyone is interested in. To sustain an arc there needs to be high current flow, not just normal use. Where was all the current going and why?
The only answer that makes sense to me is that one of his LFP banks had a defective Cell. The result would be that all of the other LFP banks would start to dump their power into the bank. I can think of no other reason for a fuse to arc. The current needs to go somewhere.
 
Into a failed pack….. parallel packs always need inter-pack fusing, with stuff that won’t catch fire. We were discusssing this 15+yrs ago on the outback power forum when I was messing with wet Nicad…
Agreed, this seems the most likely.
 
So maybe I don't need to be so worried about going to a metal case since I have both class T and stupid honkin' big MCCBs. Between them nothing should blow up.

But I might do the metal boxes just so these darn things are finished already...
 
Yes, that was my reasoning as well. A cell fails, the other packs dumping massive amounts of current into the pack, the fuses not able to handle it/arcing, cells (or even just one) venting, and the arcing fuse igniting the vent gasses. If the current was high enough, probably none of the fuses on the different packs would be able to quench the arcs (which is why a high AIC is required for these). I do wonder how that high of a current could develop even with a single cell shorted. I also wonder what the BMS was doing...

Of course, this is all speculation on available data, but I think it's a useful thing to do.

For reference, I have shorted two parallel 48V LFP packs in the past (on purpose). Both the JK BMS on them and the Class T fuse were able to deal with this. I even bypassed the BMS at one point to see how the Class T fuse would handle it on its own. It was essentially a non-event.
 
So sorry to hear about your loss. Ive had 2 fires in my life, neither destroyed my home, and they were awful.

Free advice, hire an independent adjuster when dealing with your insurance company. Well worth whatever they charge.
 
Yes, that was my reasoning as well. A cell fails, the other packs dumping massive amounts of current into the pack, the fuses not able to handle it/arcing, cells (or even just one) venting, and the arcing fuse igniting the vent gasses. If the current was high enough, probably none of the fuses on the different packs would be able to quench the arcs (which is why a high AIC is required for these). I do wonder how that high of a current could develop even with a single cell shorted. I also wonder what the BMS was doing...

Of course, this is all speculation on available data, but I think it's a useful thing to do.

For reference, I have shorted two parallel 48V LFP packs in the past (on purpose). Both the JK BMS on them and the Class T fuse were able to deal with this. I even bypassed the BMS at one point to see how the Class T fuse would handle it on its own. It was essentially a non-event.
Cell failure was my initial thought also. BUT in that case the fuse would need to be rated only for 3.4 volts as only one cell of the pack would fail and pack voltage would differ only by 3 volts from other packs. Sustained arcing is pretty unlikely if not impossible with 3 volts, electric arcs typically need 15-20v minimum.

Fuse could still provide as a ignition source for gases. I’d also take the fire investigation results with a grain of salt, everything seems pretty toasty..
 
the fuse would need to be rated only for 3.4 volts as only one cell of the pack would fail
In a Lihium pack it is the current potential that matters. The voltage potential across each cell is still the pack voltage, just as it is at any other point in a series string. Voltage adds in series. The only place where the cell voltage is that low is the BMS sensing wires.
 
In a Lihium pack it is the current potential that matters. The voltage potential across each cell is still the pack voltage, just as it is at any other point in a series string. Voltage adds in series. The only place where the cell voltage is that low is the BMS sensing wires.

I believe that what he meant was that if one cell shorts, the pack voltage drops with 3.2V, meaning a potential difference of 3.2V between that pack and the others in parallel with it.
 

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