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

hankcurt said:
@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.
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From what I gather, the difference with LiFePO4 chemistry is that burning doesn't release additional oxygen.
 
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JWLV said:
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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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?
 
time2roll said:
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?
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The "solid state" battery discharge specs were not robust, and it's more expensive and dangerous than a LiFePO4.
 
LeoThomson said:
Excuse my ignorance, but is water the right way to put out a lithium battery fire?
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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?
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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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LeoThomson said:
Excuse my ignorance, but is water the right way to put out a lithium battery fire?
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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.
 
hankcurt said:
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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Thank you for the detailed answer, much appreciated.
 
While researching if there was something new about dendrites, I ran across this, and it makes me ask a question about Will's test - because this publication talks about dendrites in the so-called solid-state battery:

www.designnews.com

Three Ways That Lithium Dendrites Grow

New research shows that lithium metal crystals grow in three different ways in lithium batteries, depending upon the current level at which charging takes place.
www.designnews.com www.designnews.com

And what I'm reading into it is that perhaps these solid-state batteries aren't designed to handle the ultimate dendrite from a drill going through it from the outside. :) Yes, that forces an event.

BUT, under normal non-penetrating use where the growth of dendritic material can short or penetrate the separator, is either not there or vastly attenuated from previous types making these saf(er). Not as much as we LFP afficianados are used to, but maybe consider the solid-state an improvement over previous types under non-penetrating conditions.

And while it may not be related to the Chin's new battery, the *research* cells indicated that abuse with high-current could override these no-dendrite safety improvements. It is unknown if purposely abusing a Chin's solid-state with very high currents would do the same or if the bms would prevent that from happening.

According to the Amazon description, the new electrolyte of this "Semi-Solid State" is "very safe and environmentally friendly". And "effectively suppress the formations of substances that cause battery failure". To me, that suggest the suppression of dendrites. And perhaps not have any major harmful effects if Will breathed in a snootful of all that junk when the drill-dendrite got driven through it. :) I am not a doctor though.

Here I am only considering the cells themselves, and not the performance of the all-in-one unit overall.
 
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I fooled myself and let my marketing guard down!

Thought about it for a bit.

Chin's description on Amazon uses two definitions: "Solid State" and "Semi Solid Lithium Technology" (as of the time of this writing) is contradictory. Either it is, or is not, solid-state. Using electrolyte answers that question.

One must be careful when using buzzwords around us battery nerds!

Until further details are known, what we have here is a cell with an improved electrolyte that inhibits the growth of dendrites like a *real* solid-state cell would do. Um, Ok.

But Will proved that unlike a solid-state cell, this version, the "semi-solid-lithium technology" will go up in flames if punctured just like previous tech.

AND - the claim of being environmentally friendly - is compared to WHAT? One of your existing products? To one of your LFP cell's own electrolyte? Or to that of a lead-acid battery? To do that would mean revealing all the chemical components of your electrolyte.

Whew, thought I lost my marketing mojo. :)
 
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Substrate said:
Chin's description on Amazon uses two definitions: "Solid State" and "Semi Solid Lithium Technology" (as of the time of this writing) is contradictory. Either it is, or is not, solid-state. Using electrolyte answers that question.
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Contradictory marketing terms? Stop the presses! :)

Solid State just means a solid electrolyte, but it more commonly refers to a solid electrolyte paired with a lithium metal anode (as described in your article). Solid state lithium batteries are not new - 10 years ago there were already EVs in France that used them. The longest range version of the Mercedes e-Citaro bus uses a later version of those same batteries. But Bollore's batteries need to be heated to 80 deg C to work well, and even then they don't put out as much power as conventional cells because lithium ions don't flow as freely through their solid electrolyte. Bollore also used old-style LiFePO4 cathodes with low energy density, offsetting a lot of the gains you get with a lithium metal anode.

The goal is:
- lithium metal anode
- solid state electrolyte (to prevent dendrites)
- high density cathode (take your pick)
- low temperature operation

Quantumscape gets a lot of attention. They have the lithium metal anode, high density cathode and low(ish) temperature operation. They use a "semi-solid state" electrolyte. The anode sees no liquid, but they use a liquid/gel electrolyte on the cathode side, which they call a "catholyte", to help get the ions moving.

What does Chins use? I don't know, but it's not that.
 
Yep - *overall*, the improved electrolyte with an attenuation or retardation of dendrite growth is a good thing!

Especially when abused and recharged. It may also serve to extend service life as well. We'll need another 10 more years to see, since sausage-factory cycling under lab conditions does not represent real world usage.

And of course this is all for naught if the manufacturing process isn't tight and you have poor offsets, or the cells are allowed to delaminate and come back together with skewed offsets by not using proper compression in the consumer item (like laptop case itself) cell surrounds. (Quality-made cylindricals naturally solve this problem at the outset, but it was not unheard of for some cell makers to have bad offsets too, and might have been one of the issues that made a very early EV using LFP's to have an event and got bad press. The LFP was fine, it was a manufacturing mistake the cause - but back then reporters lumped all lithium chemistries as one and the same and so got the blame.)

But, if you take one camping with you, (like every lithium battery maker shows), break out the guitar, and suddenly your battery is attacked by a flock of woodpeckers - it's game over with these. Or if Will sneaks out from a bush and puts a drill through it. You still have to call the fire department. :)
 
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Substrate said:
Yep - *overall*, the improved electrolyte with an attenuation or retardation of dendrite growth is a good thing!

Especially when abused and recharged. It may also serve to extend service life as well. We'll need another 10 more years to see, since sausage-factory cycling under lab conditions does not represent real world usage.

And of course this is all for naught if the manufacturing process isn't tight and you have poor offsets, or the cells are allowed to delaminate and come back together with skewed offsets by not using proper compression in the consumer item (like laptop case itself) cell surrounds. (Quality-made cylindricals naturally solve this problem at the outset, but it was not unheard of for some cell makers to have bad offsets too, and might have been one of the issues that made a very early EV using LFP's to have an event and got bad press. The LFP was fine, it was a manufacturing mistake the cause - but back then reporters lumped all lithium chemistries as one and the same and so got the blame.)

But, if you take one camping with you, (like every lithium battery maker shows), break out the guitar, and suddenly your battery is attacked by a flock of woodpeckers - it's game over with these. Or if Will sneaks out from a bush and puts a drill through it. You still have to call the fire department. :)
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I'm always hiding in the bushes with my drill looking for batteries left alone. You guys better watch out ?
 
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