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CATL Thermal Runaway Management System

Will Prowse

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Look at the level of integration here. There seems to be no wasted space in the EV module in the second half of the video. Very impressive:


And overpressure relief valve is situated on the bottom. Terminals on top.

These packs are going to last so long. And the level of safety is improving quickly. I have not seen a EV battery fire on the news for some time. And the statistics for EV fires is incredibly good now. Extremely rare event.
 
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Didn't just switching from NMC or NCA chemistry to LFP make the biggest difference of reducing thermal runaway and fires?
Also, I would guess that improvements in BMS especially with active balancing are making batteries safer.
 
The issue with LFP for EVs is weight being higher and energy density being lower than NMC. That said, if I had to buy an EV and had a choice, I'd get LFT just because I don't like the idea of the underside of my car being an angry flamethrower.

Yeah yeah I know gas cars can burn too, yeah yeah gas is extremely flammable, yadda yadda, difference is you can put a gas fire out with normal stuff while these NMC EV fires can't be put out nearly as easily. Also, gasoline itself isn't flammable, it is the vapor that burns. A 20 gallon tank of gas won't explode like in the movies. An out of control NMC pack will all go up quite fast and quite forcefully. I'm just not comfortable with it. LFP would greatly mitigate my concerns.

Also I wonder about road safety and overall road wear, these EVs are heavier and that results in more road wear (how are they going to pay for the repairs without a gas tax?), and also barricades and such don't do as good of a job against heavier vehicles (though aren't they supposed to help keep box trucks and semi's sort of in check? Maybe not, maybe semis are a lost cause). Just things I wonder about.
 
For cars, the main limiting factor right now is LFP's relatively lower volumetric energy density. The increased weight obviously affects the car's performance but there simply isn't any more space to cram in more cells for the current generation of skateboard EV designs.

The effect of EV weight on road wear is a wildly overblown point because almost all of the wear comes from semi-trucks due to the "fourth-power law" https://en.wikipedia.org/wiki/Fourth_power_law. Road safety is definitely a risk: not because of increased weight, but because of the extreme torque/acceleration of popular EVs. Hopefully ADAS technology keeps improving to keep both drivers and pedestrians safe.

It's pretty clear that LFP batteries will eventually take over the mainstream car market, while high nickel will still have market share for performance vehicles, trucks etc. Hopefully some of the next generation doped LFP chemistries will improve on their performance characteristics without losing too much cycle lifespan.
 
This recent Tesla crash was pretty impressive

 
This recent Tesla crash was pretty impressive

Wow! And that is a new 2024 tesla. That is unfortunate.
 
This recent Tesla crash was pretty impressive

Not much left of that thing. I wonder if they will be able to determine what caused the crash. Bad driving or vehicle failure of some sort? I'm guessing we'll never know, it's not like it's going to get airplane crash level treatment.
 
Wow 33 year old dead at the scene. “a vehicle described as a 2024 Tesla impacted with a tree at a high speed, causing the electric vehicle to catch fire”
 
For cars, the main limiting factor right now is LFP's relatively lower volumetric energy density. The increased weight obviously affects the car's performance but there simply isn't any more space to cram in more cells for the current generation of skateboard EV designs.

I think the automotive designer has some degrees of freedom to accommodate almost any cell volume needed.

Just the ride height of the typical XUV vs. sedan would cover most needs.


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New inverters are coming to where the EV packs at 400volt can just be tied to inverter.

megarevo example. Of course EV makers are were talking about going to 800volts for packs.

IMG_7206.png

IMG_7205.jpeg
 
The issue with LFP for EVs is weight being higher and energy density being lower than NMC. That said, if I had to buy an EV and had a choice, I'd get LFT just because I don't like the idea of the underside of my car being an angry flamethrower.

Yeah yeah I know gas cars can burn too, yeah yeah gas is extremely flammable, yadda yadda, difference is you can put a gas fire out with normal stuff while these NMC EV fires can't be put out nearly as easily. Also, gasoline itself isn't flammable, it is the vapor that burns. A 20 gallon tank of gas won't explode like in the movies. An out of control NMC pack will all go up quite fast and quite forcefully. I'm just not comfortable with it. LFP would greatly mitigate my concerns.

Also I wonder about road safety and overall road wear, these EVs are heavier and that results in more road wear (how are they going to pay for the repairs without a gas tax?), and also barricades and such don't do as good of a job against heavier vehicles (though aren't they supposed to help keep box trucks and semi's sort of in check? Maybe not, maybe semis are a lost cause). Just things I wonder about.
Sedan-type EVs aren't significantly heavier. When you get to SUVs, they are, just as with an ICE SUV. The killers of road surfaces are semi-trucks.

Many states collect an additional fee (typically $100 - $200) every year at vehicle registration for EVs, to make up for road taxes typically collected at gas pumps. If you do the math, these fees are often *more* than an average vehicle would pay in gas tax.
 
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A lot of people obviously forget that EV's & Batteries withing have changed a LOT over the past 10 years... The fastest technological evolution in fact. The majority of EV fires were of earlier designs and even those numbers were not genuinely significant overall compared to the volume. Additionally, the vast majority of those fires were to damage incurred during accidents which compromised the physical cells. Battery Packs built now are "quite" different as are the cells withing (all chemistries).

CATL like all the other major players are advancing the chemistries at an exponential pace and along with that al, all the associated tech. The new BMS', fire control & sense systems (as shown above) and even their CTP Designs make them virtually bulletproof & near indestructible.
 
The new BMS', fire control & sense systems (as shown above) and even their CTP Designs make them virtually bulletproof & near indestructible.
Not much left of that thing. I wonder if they will be able to determine what caused the crash.
I am glad to see companies like CATL working on better designs, safety, active cooling etc. (would like some of those features for my ESS !)
I'm not sure how any of those features would have made any difference in the 2024 Tesla, obliterated against the tree in that crash.
I wonder if they can estimate the speed that must have been involved, based on the damage.
 
I am glad to see companies like CATL working on better designs, safety, active cooling etc. (would like some of those features for my ESS !)
I'm not sure how any of those features would have made any difference in the 2024 Tesla, obliterated against the tree in that crash.
I wonder if they can estimate the speed that must have been involved, based on the damage.
Doesn't take very long for a Tesla to get up to some pretty high speeds if the accelerator is fully depressed / stuck. They are pretty darn speedy.
 
By the time Lithium chemistries are completely mature, we won't be using them any more.
sometimes the reason we don't get new technology sooner is the invested amounts in older present techs has not been recovered to margins of converting to newer tech. old stock would take a hit too. They usually do phase outs over time.

when computers were first coming out for public sales ppl chased bleeding edge. lot of vendors were losing money with the out dated stock. everyone wanted bleeding edge. I learned to buy stuff a generation or 2 older because as you say it was being ironed out - sorted.

Most ppl Want it NOW. Why initial now prices are also high then prices drop later as determined by market. Sometimes prices will go up with great products.

For another instance if EV 800volt batteries start trend then EV 400volt manufacturers might go solar directions to run new inverters as previous pointed out from Megarevo vs shutting down lines. Market re-directs just a thought. Lithium might become solar oriented if made safer. density vs density


""""
Lithium ion batteries have one of the highest energy density among any battery types. These batteries provide an energy density of about 100 Wh/kg to 265 Wh/kg. LiFePO4 The energy density of an LFP battery is slightly lower than a lithium-ion battery. Their energy density falls between 90-165 Wh/kg.
"""""


Having come from a large corporation will say BEAN COUNTERS OFTEN WIN for decisions. They ruin things too. Am trying not to go off topic but safety has a price point with them.. cheaper the better so cut corners. roll the dice.

Notice video stated insulation comes from aircraft industry well Boeing has a not so good reputation right now. Again not trying go off topic but sourcing matters for building things.
Cabon fiber materials used on the fatal Titan sub were sourced bought from Boeing and think it was mentioned they were old stock
https://www.businessinsider.com/oce...old-material-bought-boeing-report-2023-6final

Sourcing of components can make and break end items when assembled as complete component. So root cause has to be chased. From the drawing board to the proto types to R&D proof to customers is sometimes long. If short time then things may have been rushed. Some manufacturers want status of being first even if it is bad. Employees often make or break too - weakest link in a chain will be seen with a heavy pull. Sign use to say "never enough time to do it right first time but always time to do it over."

BEAN COUNTERS will always scape goat too. These failures can be traced if they want to really see. New designs are always welcome. Bleeding edge involves a cut from the old mold of doing things.

PPL use to shout get a horse at ppl with broken down ICE.
 
Just when we get all this figured out, current LFP will be replaced by solid state batteries.

Solid state batteries have an energy density that is at least a magnitude greater energy density than current lithium batteries. They are also supposed to be more fire resistant and be able to charge at a really hight C-rate.

They are currenty making them in the lab and even in production for a few applications (like medical uses), but they are still probably 4-6 years for cost effective manufacturing for large scale use like cars. They are working on it. Almost every major auto manufacturer is spending billions partnering or working on production solid state batteries.
 
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So when my cycle count is getting up there on LFP - the soild state batteries will be ready for market!!
I hope so, but no doubt in my mind, there will be something better for sure in five-six years. Excited to see what it is.
 
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