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Will's Review of Chins "Solid State?" Battery (Ganfeng LiEnergy Cell)

Will, you really lucked out in the first video when you poked a hole into the pack with the screwdriver.
You could have burned down your workshop. A bigger hole would have ignited it just like what happened afterwards. Also the other 13 cells were within inches of it. By the way, happy birthday.
 
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@Will Prowse Thanks for following up with the same test on a lithium iron phosphate cell of similar dimensions. I also appreciate the extra notes you put in the video with the temperature response curves and the run-away temperature for each chemistry.

And it is also relavant to the question @Cyanlite previously posted in this thread about the razor battery. I believe those are lithium iron phosphate cells from BYD. Part of the secret sauce as to why they have so little reaction to puncture is their surface area to volume ratio. By making the cells narrow and long, BYD gives the heat from internal damage a way to dissipate more easily, so the extremely high temperatures required for lithium iron phosphate oxygen release are never reached inside the battery. As long as the battery pack construction also facilitates the heat dissipation, the cells should be really safe.
 
@Will Prowse Thanks for following up with the same test on a lithium iron phosphate cell of similar dimensions. I also appreciate the extra notes you put in the video with the temperature response curves and the run-away temperature for each chemistry.

And it is also relavant to the question @Cyanlite previously posted in this thread about the razor battery. I believe those are lithium iron phosphate cells from BYD. Part of the secret sauce as to why they have so little reaction to puncture is their surface area to volume ratio. By making the cells narrow and long, BYD gives the heat from internal damage a way to dissipate more easily, so the extremely high temperatures required for lithium iron phosphate oxygen release are never reached inside the battery. As long as the battery pack construction also facilitates the heat dissipation, the cells should be really safe.

From what I gather, the difference with LiFePO4 chemistry is that burning doesn't release additional oxygen.
 
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Will, you really lucked out in the first video when you poked a hole into the pack with the screwdriver.
You could have burned down your workshop. A bigger hole would have ignited it just like what happened afterwards. Also the other 13 cells were within inches of it. By the way, happy birthday.
No, the other cells weren't nearby, what you see is an empty battery case.
 
The drill test is great and yet I would be more concerned about general operating conditions such as over voltage protection.
Will there be a second battery that actually works?
 
The drill test is great and yet I would be more concerned about general operating conditions such as over voltage protection.
Will there be a second battery that actually works?

The "solid state" battery discharge specs were not robust, and it's more expensive and dangerous than a LiFePO4.
 
Excuse my ignorance, but is water the right way to put out a lithium battery fire?

I don't think there is a "right way" to put out a lithium fire. Isn't the only thing you can do is smother the external flames a bit until it burns itself out? If you were to dunk it in a tank of water, it will just keep on burning while the water turns to steam. If you were to bury it in sand, it will just keep burning, heating up the sand.
 
Excuse my ignorance, but is water the right way to put out a lithium battery fire?
Eh.. this is why 'safety' is such a vague thing and is usually treated as lowest common denominator when technically 'it depends' on soo many things.

If there is nothing nearby which is ignitable the safest thing to do is not mess with it!
If there is something nearby which is ignitable and can be moved without exposing yourself to danger, just move it.
I think actually disturbing/messing with the fire itself comes after that or only if that is not possible.

But 'putting out' a fire is not always necessary so much as 'keeping other things from catching on fire' is. Pouch cell is guaranteed hot garbage (ha jokes) whether you put it out or let it burn, so putting it out is optional. Keeping other things from burning is more important.

Keeping other things from burning or catching on fire could be multiple forms such as slowing conduction of heat from source to it, or lowering temp of source by conducting some of its heat away into something cooler that you don't care about heating up (putting water on it could work, dirt, flour, etc), lowering temp of thing you are trying to avoid igniting (spray it with water probably works), add thermal mass to thing you don't want to ignite (water works again, if you can spray it periodically or constantly). Even just spraying water on the ground in a circle around this fire would be a viable way to prevent damage to the concrete (charring/cracking/spalling etc).

So just because water might not be the 'right' way to 'put out' a fire doesn't mean you don't have a range of options of how to use water to keep a situation from escalating. Directly spraying it onto the thing that is on fire may not be the best way to use it, but its also not the only way to use it. I can't think of many fire situations where water would have no use at all. I think the main thing is to think before you act. You don't want to make a tiny fire MORE dangerous by indulging your knee-jerk reaction impulses. I would venture that the likely most important first thing to do in most fires is actually to protect your eyes and lungs and THEN think about managing the heat energy.
 
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Excuse my ignorance, but is water the right way to put out a lithium battery fire?
You might be thinking of the way lithium metal reacts with water violently to form lithium hydroxide and releases hydrogen gas in the process, which will usually self ignite from the heat of reaction.

With a lithium ion battery fire, most of the heat is coming from the flammable electrolyte reacting with the oxygen released from the electrode material. There isn't so much elemental lithium available to react with the water that adding water will make the situation worse, and as @Vigo said, the important thing is to bring down the temperature and prevent fire spread to other nearby materials.

There was an extensive test done in 2013 on EV batteries to see how effective water was at extinguishing an electric car fire. For people who like reading and pictures of burning batteries, there is nearly 200 pages of smoldering goodness to enjoy. It appears that they made a car mock-up with a Chevy Volt battery in it and then used burners to heat it until it caught on fire. They measured internal heat, car chassis electrical current and fire hose electrical current. All of the hose nozzle current readings were under 2 ma. Anyway, they came to the conclusion that water could be safely used to contain the lithium battery fire, with a high risk of self re-ignition once it appeared the fire was out.
 
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