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Lithium Batteries (LiFePo4) - how safe are they ? - (wife getting paranoid)

EPicTony

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I have an EG4 battery bank (6 batteries) Well my wife is seeing EV cars on fire after the hurricane and they can't get the batteries extinguished once they start burning, especially with water thrown in. Now I'm getting 50 questions like "are you sure they are safe?" "What happens if they catch on fire?" "if they catch on fire how will we put the fire out?". Anyone else had to reassure someone about battery safety ? Do they ever catch on fire? Thanks for any info !
 
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LFP chemistry is dramatically safer than the NCA/NMC/LMO chemistries typically responsible for EV fires.

LFP is flammable, but the flame is not self-generating. LF does not produce oxygen as do the other referenced chemistries as they undergo thermal runaway.

NCA/NMC/LMO burn, release more oxygen, burn, relase more oxygen, etc.

LFP does NOT do this. If you hold a torch to it, it will burn. If it undergoes thermal runaway, it fails. It might get hot enough to melt or ignite other nearby flammable items, but it is NOTHING like the EV fires that worry your wife.

They represent negligibly more risk than a flooded lead acid battery.

EDIT: A recent post on the subject:


The height of the humps represent the relative risk of fire. Note LFP barely registers in comparison to the others.
 
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Tell her the danger is mostly just melting wires and sparks, same as any other electronic equipment / wiring. They will likely catch on fire and burn like anything else would if lit on fire, but are not adding to the problem more than anything else burning would. It's the cabling you really want to watch out for. Tell her the EG4 batteries are UL Listed also, that they were tested to meet certain safety guidelines for installation in a building. Assuming you got the UL listed ones.
 
Tell her the danger is mostly just melting wires and sparks, same as any other electronic equipment / wiring. They will likely catch on fire and burn like anything else would if lit on fire, but are not adding to the problem more than anything else burning would. It's the cabling you really want to watch out for. Tell her the EG4 batteries are UL Listed also, that they were tested to meet certain safety guidelines for installation in a building. Assuming you got the UL listed ones.

This is a very good point.
 
It's funny seeing people worry about ev fires. Like we haven't been driving around for the past 60 years with 20 gallon tanks full of gasoline mere feet away barreling 80mph down the highway. What could go wrong?

Hell, i had a nice old dodge d200 that had the tank in the cab. Safe much?
 
It's funny seeing people worry about ev fires. Like we haven't been driving around for the past 60 years with 20 gallon tanks full of gasoline mere feet away barreling 80mph down the highway. What could go wrong?

Hell, i had a nice old dodge d200 that had the tank in the cab. Safe much?

Kinda. Gas vehicles don't catch on fire because they were submerged in water.
 
"are you sure they are safe?"
100% safe. Neither you or I are dead are we?

"What happens if they catch on fire?"
If that happens we can turn the heat down in the house and save money. You did stock up on hotdogs and marshmallows at the grocery store?

"if they catch on fire how will we put the fire out?"
We didn't start the fire.

 
Kinda. Gas vehicles don't catch on fire because they were submerged in water.
nah, they just spontanious catch fire while driving on the high way ( 200.000 times in the last years in the us)...

erm, i would think if your wife is made aware of that, she will be a bit more easy on your batteries ( mine was ;) )
 
The major difference between an EV catching fire (with lithium cobalt cells) and gasoline is gasoline fires can be put out traditionally and the fire departments all know how to, while the lithium fires can't be (aside from LFP).

I don't want an EV anyway, but particularly don't want one with these cobalt chemistries.

But then, I have carried such a cell in my pocket for years, used laptops with auch cells for years, so..... maybe I'm just dumb.
 
They represent negligibly more risk than a flooded lead acid battery.
I would be careful with that statement. Poorly implemented FLAs are actually a huge risk, especially installed inside a house.

But, complete agreement that the LFP is not in the hazard class of NMC and similar chemistries. Most of the risk comes down to the electrical and not battery hazard.
 
I would be careful with that statement. Poorly implemented FLAs are actually a huge risk, especially installed inside a house.

But, complete agreement that the LFP is not in the hazard class of NMC and similar chemistries. Most of the risk comes down to the electrical and not battery hazard.
In order to burn LFP you have to drive major prolonged thermal input around the cells for a while, the goal of fire arrestors was to prevent any chance of BMS fire, a dead short of HV dc voltage through the BMS is really the only thing that I know could drive thermal runaway powerful enough to light a 100Ah cell
 
Will recently did a couple videos on this topic, showing the thermal runaway effect of lithium-ion based cells (similar to what's used in EVs):

He repeated the test with a LiFePO4 pouch, much safer:

These videos hopefully can put your wife at ease!
 
I have an EG4 battery bank (6 batteries) Well my wife is seeing EV cars on fire after the hurricane and they can't get the batteries extinguished once they start burning, especially with water thrown in. Now I'm getting 50 questions like "are you sure they are safe?" "What happens if they catch on fire?" "if they catch on fire how will we put the fire out?". Anyone else had to reassure someone about battery safety ? Do they ever catch on fire? Thanks for any info !
If they catch on fire you call the fire dept. Duh.
 
Perception is a funny thing.

My mom used to always make sure the toaster on the kitchen counter was unplugged if we were leaving the house in the morning, because it "might catch on fire". However, she never gave a second thought to the the pressurized natural gas line in the basement with a valve the would automatically open by itself and dump gas into an igniter. As the little kid who had the bedroom right next to the furnace, I sometimes thought about it a lot.
 
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