Last fire.. :-(

I hate it when a disaster thread like this is started, and all attempts to find what went wrong are met with incredulous blocking of a search for problems.

I guess he simply doesn’t have any pictures of the completed build.

or in his mind the problem was bad cells, and is not willing to look elsewhere for a problem. So, this isn’t a learning thread, it is a thread showing off his new pack. Oh well.

Supervstech said:

I hate it when a disaster thread like this is started, and all attempts to find what went wrong are met with incredulous blocking of a search for problems.

I guess he simply doesn’t have any pictures of the completed build.

or in his mind the problem was bad cells, and is not willing to look elsewhere for a problem. So, this isn’t a learning thread, it is a thread showing off his new pack. Oh well.

Click to expand...

"I don't do anything wrong therefore nothing was wrong with anything I did"

I provided all the pictures available.

Sorry I didn't full Photoshoot before then fire started with high resolution Camera.
What I don't have, I do have my phone...

I wonder how often you make a photoshoot of your setup, incase there is a fire. ?

If someone wants to take from it that I want to show of my new battery.. I guess that's just Envy.

I'm for sure happy with them and that the struggle that started 18 months ago finally ended.

Bad luck magnet doesn't work together with LiFePO4 atleast not the half products I got.

Incomplete list of failing purchased equipment:
(All aliX or Thailand product)
- inverter (EASun, fried my 16* 200Ah lead acid by charging it with 78v)(3* 3kw, parallel)
- the 16 batteries...
- BMS 3x (Jikong first release, Daly 250A dumb, 150A Daly smart, first release)
- battery capacity tester 2x (Mosfet)
- lab power supply
- long list smaller stuff.

Sadly in rural Thailand, you can't just get any of this at the local stores, and online can take several weeks.
With Corona even months to get replacement.
Living off grid, I need to use what I got, as there isn't really alternative.

That's besides the crappy screws, paper thin busbars, and being at the frontline, together with many other forum members, paving the road to the level of knowledge there is available now.

And yes, I'm not open for a discussion about how, according to you, absurd influential stainless steel washer would be in voltage reading.
Done that, been there and measured it.
I guess that is something you did not do.
If you did, you would see how absurd little voltage difference there is, and talks about heat with 5 watt ?? Maximal.. for real??
For a few minutes?
Remember, just topping off the charge, not mixing up a nuclear reactor.

If you like to over theorise about it..
Go ahead, make a separate thread about it.
I'm happy to contribute my readings.

Take from this thread what you like.
It's intended to be educational and show what might happen.

Not detective story.
For people who like that, your welcome to visit and investigate.

Done deal, all batteries lost.
No personal damage, and the house still stands.

All safety measures in place worked as they should, except not having by hand a small (electric) fire distinguisher.

That's available now

If people are interested in the BYD (different thread)
Perhaps possible to ship from Thailand.
I'm not making a business here, and
can't make guarantees that I also don't receive.
Help with shipment might be possible.
if so, PM me.

The bottom cell in this picture raises a red flag for me. It looks to have melted due to high internal heat.

Based on what has been discussed in this thread, I'm leaning towards a very dim view of active balancers.

After reading this whole thread, I agree with @fhorst that selfdischarge is the most likely cause.
One cell started and with the heat spreading the rest of the cells joined in the party.

That is why for grade "A" cells the selfdischarge is a critical test during the qualifying process for Grade A, B or C

And now we know that the 152 AH was a bad batch, that makes me believe the selfdischarge was the problem.

The 152AH are no longer in production, so bad luck for the early adapters like @fhorst .

All sorts of readings could help in putting system in service with periodic "check ups" readings to insure nothing goes out of whack, could something happen during a period of time in between a "check up" sure but I think there would be some sort of warning or little voice in your head speaking to you (and I'm not talking about you folks that have been off your medications ).

Testing and written recordings so down the road you can review actual #s not the "I think" #s at different SOCs, voltages with different currents whether charging/ discharging. Cell temps/ connection temps readings (ir gun can be had fairly cheap) during use of high draw items.

I think live time individual cell reading of voltage & temps is a must to give a possible warning of something going bad. If that can't be done then think about Murphy so he doesn't bite you in the butt.

Stop buying cheap azz components, if you're going to do it....do it right the first time, if stepping back and regrouping before proceeding do so, knowing when to say "when" really is the key to most things in life.

I think fhorst has done the best he could along the way and appreciate the honesty of posting this tragedy and other tribulations of trail and error projects, instead of fading into the sunset. I also think there somethings that I and others would not of done but we're not in his shoes but certainly can learn from this.

Be safe, be careful building these systems.... it hopefully will never go terribly wrong for anyone.

In the last pictures, why are the studs different diameters and different lengths? Sometimes on the same cell and sometimes on different cells?

I'm hoping I'm not just continuing the pile on fhorst, but this is quite concerning and I assume we all want to ease our minds so we have faith in our systems.

@fhorst I recall a thread some time back about "inductive" charge on the all thread used for compression. Was this you as well? I also recall most weren't convinced that it was inductive, and was more likely due to a short somewhere. If this wasn't you, maybe this is something to look at. I see that the all-thread is still not insulated or covered. Is there any damage on the thread from a short between cell casings? I would guess the fire wouldn't melt the thread like a dead short would. Thoughts?

Sky-HHI said:

In the last pictures, why are the studs different diameters and different lengths? Sometimes on the same cell and sometimes on different cells?

Click to expand...

Because the cells terminals stripped so he re tapped them to a larger diameter. Many have had to do this. I stripped a terminal and used JB Weld to hold the grub screw in place. My C rates are low so I did not attempt to tighten the nut with more that 3nm of torque.

I don't know why the lengths are different.

Supervstech said:

So, this isn’t a learning thread, it is a thread showing off his new pack. Oh well.

Click to expand...

I kind of disagree with you. I don't see any showing off of his new pack. If it was me I would be very happy to have had my family help out so I could buy it. That's all I see fhorst saying.

There is much to be learned from this thread. Most of the time when these things happen it is user error or a faulty component, and sometimes it's difficult or impossible to verify the cause. I am far from convinced the cell had an internal short and we have seen cells severely discharged come back to life but with degraded capacity.

Of course a mess of wires, fauty connection(s), mice and whatever will cause problems. You have made some very good points in this thread and many other threads and I have learned a few things from you So even if it appears to you fhorst is not comprehending your thoughts, I am and I am sure many others understand the points you have made.

Sometimes speculation is healthy as it forces us to think about things we can do to improve safety. I am learning new stuff here all the time thanks to threads like this.

At the end of the day, no life was harmed from my reading. That is the absolute best outcome.

Very glad that the second worst, not being able to rebuild, was also avoided.

May everyone who reads this thread have a healthy respect for the “hobby” work and never suffer a loss of equipment as significant as the one shown here.

I have certainly had my respect for safety design renewed by reading. Learning will never stop!

???

I'm probably in the minority .... but I do agree with Fhorst that having the balance lead on top of the nut should not be a problem. I would actually rather it be there than under the nut contacting the bus bar because that can cause problems where the primary current flows.

The voltage measurement to the BMS / active balancer would be affected very little because there is only voltage drop when there is current flow and the current flow thru those balance leads is very low.

I don't have any experience with an active balancer because I don't need one with my pack. I have seen posts from others who use an active balancer and swear by the results .... but ..... it is definitely another potential point of failure.
If I were going to use an active balancer, I would probably have it connected in such a way that I could leave it disconnected most of the time and only connect it intermittently if things started to get out of balance and monitor the pack closely while it was in service.

As to the cause of the fire, I think we can only speculate. It certainly seems that it started around the post on the one cell which was identified .... Some of the pictures of the battery posts I have seen in the past have been concerning, but I think Fhorst has probably done a good job torqueing and testing for heat at the connection points.

Environment when doing a DIY build should definitely be a major consideration. I think I would consider running some sort of stand alone air filtration system in the area the pack is stored.

I don't know anything about the 152 ah cells from EVE, but will do a little searching to see what's out there.

I'm really glad that @fhorst was much better prepared for dealing with the fire than most of us probably are and wish him success with his new pack.

Supervstech said:

I hate it when a disaster thread like this is started, and all attempts to find what went wrong are met with incredulous blocking of a search for problems.

I guess he simply doesn’t have any pictures of the completed build.

or in his mind the problem was bad cells, and is not willing to look elsewhere for a problem. So, this isn’t a learning thread, it is a thread showing off his new pack. Oh well.

Click to expand...

Yeah, I see this pretty often with folks who ask (or pay) me to fix something that blew up. They simply refuse to consider user error.

My guess is a cell got pulled really low, the resulting recharge caused polarity reversal and cell meltdown. That would be bms or wiring failure.

Honestly in previous OP's posts I noticed and occasionally pointed out bad practices, but was met with the iron wall of a set mind. Here we are two fires later.

I hope this is the last one. I strongly suggest the OP post the entirety of their bills and design on a new thread for others to check. I know I would be questioning my own process at this juncture.

fhorst said:

I wonder how often you make a photoshoot of your setup, incase there is a fire. ?

Click to expand...

This is probably the single most valuable piece of advice from this thread and I will do that myself right now.

HRTKD said:

The bottom cell in this picture raises a red flag for me. It looks to have melted due to high internal heat.

Click to expand...

Do you mean the way it looks caved in around the terminal? I suspect the same effect could come from heat conducted by the bus bar. The top of the cell casing is pretty thin, isn't it?

cinergi said:

This is probably the single most valuable piece of advice from this thread and I will do that myself right now.

Click to expand...

Some might call me crazy.. photogrammetry 3D reconstruction is quick and easy with modern CPU/GPU.

When I do some work, I take 1-10 photos from various angles of the same spot, with phone camera. No specific movement pattern, just point at the same spot and physically move the camera left/right/up/down relative to the spot to get parallax view. The software later turns that movement into 3d..

Later it’s possible to reconstruct where things are. Agisoft makes metashape which works well, and reality capture is another option that is efficient.

For anyone worried about it taking forever, it can work with as few as 2 images, and even 5 can provide a lot if there’s a lot of overlap.

curiouscarbon said:

Some might call me crazy.. photogrammetry 3D reconstruction is quick and easy with modern CPU/GPU.

When I do some work, I take 1-10 photos from various angles of the same spot, with phone camera. No specific movement pattern, just point at the same spot and physically move the camera left/right/up/down relative to the spot to get parallax view. The software later turns that movement into 3d..

Later it’s possible to reconstruct where things are. Agisoft makes metashape which works well, and reality capture is another option that is efficient.

For anyone worried about it taking forever, it can work with as few as 2 images, and even 5 can provide a lot if there’s a lot of overlap.

Click to expand...

80 pictures, or better 160 picture of each terminal does take a long time.

The overview pictures made aren't apparently "high resolution" enough.

Due to limited bandwidth (off grid, slow internet) I do crop pictures to 25% in my first post.
One 3Mb picture takes 5 to 20 minutes to upload....
Something this site doesn't like (parsing error) what needs a new upload.
Outside rainy season it's a bit better.

It's not taking pictures that would take ages..
Sending them here would.
Days, with the whole family cut of internet to keep the bandwidth open.

For my personal documentation, I have all the pictures I need / like or want.

Like said, you are welcome to inspect yourself to do your Sherlock things.

Lol..

I guess I'm the only one without iron plate!!!!

Really..
Please provide any evidence that a stainless steel washer will affect the voltage readings to a level it would mess up a BMS.

(What was, for the 5th time, NOT installed)

And please, please please provide me with the proof that if (not possible yet, as the. DIY BMS wasn't installed yet) a discharge load of max 1.5A from a copper lug between 2 stainless steel nuts, with 2 large heavy bus-bar attached would be able to increase the Temperature to fire dangerous height!!
Maximal 5 watts..
For a few minutes, just enough to burn of the excess from 3.65 to 3.55v
Charging itself would have stopped..

Anyone who thinks this is a reality is probably blinded my the all-knowing knowledge of Supervstech..

@ Supervstech, I don't say to do or that you pretend that you do.

Telling that I have a plate when I don't thrust your blue eyes about it, with out any evidence, it's just bullshi...
And those who parrot after you have that in their brains.

Stay realistic people.
3.2v, maximal 1.5A.. 5 watt.
Discharge from 3.65 to 3.55 of 280 or 152ah battery.
That's 5 watt for a minute?
On a heat sink...

Not even the bus-bar contacts...
Stay realistic.?

Provide bills of the products I bought? Spanish inquisition??

If you like to know, just follow my post In this forum.
All things purchased and used for my LiFePO4 adventure has been shared.
How they worked, or did not work.

How some could be repaired (like the discharge tester, replacement of the Mosfet) and things that failed without option to repair.

How China warranty usually is crap.
And after my fight and costs over my 250Ah Daly with them..
I did not even bother anymore to claim the defective 150Ah smart.
It would have cost me more on return and time then just cry about it and know Daly doesn't earn it's name in the high ampere sigment.
Now 12 months later, perhaps they do.

So chop chop Sherlock's.
All information you like to know is in this forum

@fhorst ..... from yesterday til today, did anyone really disagree about the balance lead placement? I actually agreed with you about that .... but you want to just call everyone names.

Seems like mostly a straw man argument .... I think maybe you are only happy if arguing and are trying to bait people into it ..... Guess I took the bait, but won't do so again.

@Bob B ,

No absolutely not trying to pick a fight with everyone.
People who parrot to tend to P. me off..

When I get called iron plate in my mind... I'm not picking a fight, responding to accusation.
I guess I got drawn in that by @Luthj ....

It's fine to have difference of opinion about using stained steel or not.
Pointing it to "the source" of the fire, without any further knowledge...
And that suddenly seems to be the standard?? Without any proof that it would increase to the dangerous levels that it was claimed...
I guess I got dragged into that by @Supervstech also...

Obviously, I disagree and challenge him to provide proof for his statements.
My multimeter tells he is wrong.
But that can be misinformation also

Reason for the fire:
(Choose one or all below)
- cascade of smaller errors in 18 months tinkering
- failure of BMS (3 times)
(No after 3 days wasn't my fault, all units got returned. Yes, 250A Daly can stop after 3 months successful working,
And new 150A Daly smart BMS can not be functional from the start)
- Bad batch of Eve cells (152A)
- too long screws pushing on the bottom, not the bus-bar.
(Adding additional washer fixed this, and no visual damage, no strange electrolyte smell, so not perforated. Still... Something I think should not have happened if the seller would have provided studs
- Thailand!
Heat, moisture, dust, so much dust, rotents, amphibians and insects.
(While insects usually don't make direct (short) damage, their presence does)
- Learning curve.
Many things I can't call an error or accident, but they do add up. Like relocation 4 time, and re-wire of BMS after failure...
Releasing the compression, weak threads, replace BMS wires, clamping again..
till many threads failed.
- not using torque meter at start, and not having the knowledge available how many it should be (3.5-4Nm)
- not using grubscrew, and Loctite, using Loctite without primer
- not compress the cells.
February/March 2020 was "all about" keeping the cells cool and how they best should have space between them...
True for CalB, not Eve....
- use materials available.
That includes uneven length of grubscrew. Why? Because there isn't even size available and post order takes 2-4 months (start Corona time)

I guess that's the whole list
Choose what suits you best.

In my opinion, being there, living it, doing it.
Combination of all above.
Not one BMS wire, or rotent.
Perhaps it was damaged and did short.
The type of wire should have made it a small "dent" in the abuse a cell can handle.
With the 18 months past, the drop that made the bucket overflow.

I never thought the cells weren't safe anymore to use.

The cells that got hot in the previous fire, got replaced.
That was smoldering wood on top of the cells (6 got replaced)

Living off grid is also no fire department to safe our ass..
As I don't have a death wish for me or family.
You can be sure that I did not take any more risks then any responsible father would take for his family.