LTO battery fire

[Systems Planet]

My home build LTO battery had a fire last night.
We heard a large pop and came out to find a small arc fire in one of the cells. One of the cells had popped completly apart. The wiring was arcing and causing a small flame.

We were running five 10 amp active balancers on five 22S banks.

Either:
- the balancer died
- a cell went bad, or
- the wiring became corroded and high current.

I post this to remind people that we need a mechanism to detect these events and shut everything off and alert you to the problem.

LTO chemistry is amazing.
This could have been much worse.
Our small arch fire was easily put out with a CO2 fire extinguisher.

The battery cart was on wheels and easily wheeled outside, away from the house, while we dealt with the fire.

When you plan for a fire,
you're ready for a fire.

Make sure your batteries are on wheels, you have a fire extinguisher, and a fire plan to get flaming batteries away from your home.

Be safe.

 

[SparkyJJO]

Glad it ended up ok aside from the fried cells.

What's with all the alligator clips?

 

[Steve_S]

Eeeek Gads Like juggling 4 fragmentation grenades with the pins pulled. Time to revisit basics & safety methods...

 

[Systems Planet]

Glad it ended up ok aside from the fried cells.

What's with all the alligator clips?

Alligator clips connect the cells to the balancer

 

[Systems Planet]

Eeeek Gads Like juggling 4 fragmentation grenades with the pins pulled. Time to revisit basics & safety methods...

Pat yourself on the back

 

[Steve_S]

Pat yourself on the back

You're the one who had a Battery BBQ and survived to tell about it. Bottom line, its your money & butt along with all the risk of bodging together in a hap hazard method. But never mind, I've only been at it for a few decades, what do I know. Have Fun and Good Luck, just keep a fully charged Extinguisher handy.

 

[SparkyJJO]

Alligator clips connect the cells to the balancer

You were relying on alligator clips for that?

Chance that it had a bad connection and was misreading the cell voltage, and you may have had a runner that popped something. LTO doesn't just blow like that.

You really shouldn't use alligator clips for your pack.

 

[Lt.Dan]

You were relying on alligator clips for that?

Chance that it had a bad connection and was misreading the cell voltage, and you may have had a runner that popped something. LTO doesn't just blow like that.

You really shouldn't use alligator clips for your pack.

THIS.

Also, what are you powering that requires a 22S pack???

 

[Systems Planet]

Eeeek Gads Like juggling 4 fragmentation grenades with the pins pulled. Time to revisit basics &

You're the one who had a Battery BBQ and survived to tell about it. Bottom line, its your money & butt along with all the risk of bodging together in a hap hazard method. But never mind, I've only been at it for a few decades, what do I know. Have Fun and Good Luck, just keep a fully charged Extinguisher handy.

Dude. I've lived through Outback, Solark and EG4 inverters.
This is not my first rodeo.

This was a test rack that I built myself by hand and it behaved beautifully for four years. I've intentionally ran it balls out 100% charge to discharge daily.

I got every dollar out of what little I invested.

So go give your unsolicited advice to some other thread.
You are not needed here.

 

[Partimewages]

Dude. I've lived through Outback, Solark and EG4 inverters.
This is not my first rodeo.

This was a test rack that I built myself by hand and it behaved beautifully for four years. I've intentionally ran it balls out 100% charge to discharge daily.

I got every dollar out of what little I invested.

So go give your unsolicited advice to some other thread.
You are not needed here.

You probably shouldn't disrespect someone who likey knows more about batteries than all the rest of us put together.

 

[Tulex]

Today I've learned.....

LTO batteries are more likely to catch on fire than LifePO4.
Some people use alligator clips for permanent connections.
7000+ posts isn't respected by all.

 

[SamDeleted]

7000+ posts isn't respected by all

Its not the number of posts, it's the quality of content...

And I think Steve excels in both ?

 

[SamDeleted]

The battery cart was on wheels and easily wheeled outside, away from the house, while we dealt with the fire.

When you plan for a fire,
you're ready for a fire.

Make sure your batteries are on wheels, you have a fire extinguisher, and a fire plan to get flaming batteries away from your home.

Be safe.

I don't know what you're idea of safe is , running a test rack like that in a home doesn't seem very safe to me ? , especially not one you are deliberately pushing to its limits

 

[mikefitz]

remind people that we need a mechanism to detect these events

Perhaps quality engineering to prevent such events. Like Steve_S, I've been around some time and seen the results of poorly engineered setups. Luckily you survived uninjured, some don't .

So go give your unsolicited advice to some other thread.
You are not needed here.

A very unpleasant statement, not needed on a technical discussion forum.

 

[JJJJ]

You probably shouldn't disrespect someone who likey knows more about batteries than all the rest of us put together.

Well said. Very well written.

 

[Systems Planet]

Today I've learned.....

When you share a helpful post on this forum, you get:
- accused of using 'hap hazard methods'
- told to "revisit basics & safety methods"
- accused of "disrespect"
- attacked with bogus appeals to authority

Please ignore anyone on this forum who is so smart that they can't have a battery fire, or too proud to admit when they do.

Peace

 

[Systems Planet]

Perhaps quality engineering to prevent such events. Like Steve_S, I've been around some time and seen the results of poorly engineered setups. Luckily you survived uninjured, some don't .

A very unpleasant statement, not needed on a technical discussion forum.

But telling a complete stranger "Time to revisit basics" is polite?

 

[Checkthisout]

Are there salvageable cells?

 

[Lt.Dan]

But telling a complete stranger "Time to revisit basics" is polite?

Well when you neglect basic safety practices and then come on here bragging, we're not going to be too receptive.

 

[42OhmsPA]

Are there salvageable cells?

Looks like there should be plenty, just needs a little spit shine and elbow grease...
That one that blew up looks impressive.

Glad everyone was OK and it wasn't worse.

 

[Skypower]

The funny thing about this forum. You will get critique, some of which is good for your ego and that’s not, most of which is well deserved. This is a learning location, learn to suck it up, get a thicker skin and use the advice you deem appropriate. Or don’t expose yourself by posting.

LTO is the safest of the commonly used lithium chemistries. That being said, we are now using DC battery voltage that can easily have an arc fire. A bad terminal connection (resistance) can start out with heat damage (cell&buss) cascading all the way to something similar to hyper powerful DC arc welder, spraying molten debris. My guess is the cell didn’t fail per se, but it got drilled out buy arc. The overcharge failure tests I’ve seen involved one cell and the result was underwhelmingly boring, that could be quite different if it’s part of a group with higher voltage coursing through it. So an out of balance cell could also be the cause.
The critique whether or not you like it. Periodically check the torque of the cell nuts. Loose the slotted buss bars in favor of a full hole type. Drill and tap the busses for a balance lead and use large hole terminals for the end cell balance leads. Use a flame resistant (or fire retardant treated wood) support surface to evenly support the cells off the storage shelf wire mesh.
Take it or leave it.

 

[Lt.Dan]

What is dividing the cells on the bottom shelf? I can't imagine that is metal, and risk the very easy possibility of shorting a 22S bank capable of a continuous 8-10C??? If it's wood, then that's another can of worms...

 

[Tulex]

LTO is the safest of the commonly used lithium chemistries.

That's not what I am reading online.

2. Which battery type is safer?​

Both LTO and LiFePO4 batteries are considered safe options compared to other lithium-ion chemistries. However, LiFePO4 batteries have a reputation for superior safety due to their high resistance to thermal runaway and overheating. They are less prone to accidents or fires, providing peace of mind when using them.

 

[JJJJ]

There have been multiple times where I have enthusiastically presented something. Sometimes I get a thumbs up. Other times I decided to swallow my pride because the critique while difficult to swallow was spot on.

There is nothing wrong with trying new things. That is why we are here.

We are fortunate to have members who have extensive practical experience not only in solar. We are gifted with some very interesting and intelligent members who love to teach.

There is a lot to learn.

 

[Checkthisout]

OP, don't get your feelings hurt.

Would have had less critique and more LULz if you posted this in the "Up In Smoke!" Forum.

That's an impressive amount of power there.

Those kinds of cells look like you just chopped up a bunch of Optima batteries into individual cells.?