New MG4 EV (2026 facelift) - Now on MG website

[tsedge]

Sorry Tom but Terry is right ... the accepted definition of thermal runaway is where the fire is driven by self-combustion. With an LFP fire, throw over a fire blanket and it'll go out quite quickly - with an NMC fire a fire blanket will do little, as the Cobalt in the NMC chemistry will generate Oxygen as it burns, so self-combusting and maintaining (if not accelerating) the fire.

You are both incorrect: thermal runaway can occur and cause a fire whenever there is oxygen present in the environment (whether self-generated in the chemistry or ambient). The result can still be fire although the intensity is far greater when oxygen is produced by the chemistry.

LFP batteries can burn.

 

[siteguru]

LFP batteries can burn.

Nobody is disputing that ... it seems we disagree on the definition of Thermal Runaway, as it applies to battery technology.

 

[tsedge]

Nobody is disputing that ... it seems we disagree on the definition of Thermal Runaway, as it applies to battery technology.

Indeed.

 

[tsedge]

For example:

https://www.sciencedirect.com/science/article/pii/S2352152X25019334

 

[LenEV2016]

China has banned any chemistry battery that can self combust, in other words, make it's own oxygen when thermal runaway occurs, and chemistry with cobalt in the mix is going to suffer this problem.
Unless you know of a company that can compete on price and manufacturing volume that isn't in China, then I'll accept defeat yet again.

Sodium ion does not suffer with low temp problems, down to -40C, NMC or any of the ternary lithium ion cells or LFP suffer loss of capacity and shorter cycle life operating in these low temps.
View attachment 43542

As you can see, Na+ (Sodium ion) out performs the 3 chemical mix lithium cells in capacity retention and discharge rate, NMC is on the extinct battery chemistry list .....

T1 Terry

Not disagreeing with anything you are saying but I can't find anything to say they have banned NMC batteries, I can see that there is a decline in sales but they are still the battery of choice for premium long range cars.

 

[Bam Bam]

Not disagree with anything you are saying but can't find anything to say the have banned NMC batteries, I can see that there is a decline in sales but they are still the battery of choice for premium long range cars

I think it is more that they have higher fire standards, not that they are banning on the basis of chemistry directly. Chemistry wouldn't matter if it met the standards.

 

[Archev]

Any evidence of thermal and rest assured I shall definitely runaway stage left sharpish.

 

[T1 Terry]

Not disagree with anything you are saying but can't find anything to say the have banned NMC batteries, I can see that there is a decline in sales but they are still the battery of choice for premium long range cars

As @Bam Bam has already posted, the chemistry itself isn't banned, but it can't meet the thermal runaway requirements, so it is dead as far as cell manufacturing in China.
Sure, it opens up that chemistry to be built elsewhere, but would there be a market to sell them with " Solid State Batteries" being just around the corner ..... sort of like one of those spiral carpark ramps that will lead to a space port by the time it actually reaches the end .... just another corner to go round .....

Sodium ion will dominate within 5 yrs, cheap to source the materials, longer life cycle, better low temp operation, greater discharge capability, faster charging ..... Unless of course, these Donut Lab battery cells are for real and not just super capacitors .......

T1 Terry

 

[T1 Terry]

I think the premium long range market doesn't really worry about weight as much as the performance market.
The ability to handle any weather conditions, fast charging and long cycle life when being fast charged and no thermal runaway, will be the selling point for Na+ batteries in the luxury market .....

Maybe a mixed chemical battery such as Na+ cells and LFP or LTO combined battery packs ..... LTO for the incredibly fast energy delivery and acceptance properties ....
A 100Ah 900v battery, 50/50 Na+ and LTO, the LTO part charges at up to 450kW (10C), from 0% SOC to 100% SOC in 6 mins, the Na+ part, another 45kWh capacity that can charge at 5C, in the same 6 mins would take on 50% of its capacity, say 30% SOC to 80% SOC ......
using the available charging current for the whole time it is connected, so no tapering off as one chemistry approaches 100% SOC, the other chemistry can take advantage and fill up, just not to 100% SOC so that chemistry will be able to handle fast charging until you have between 80% and 90% of the battery capacity, in under a 12 min recharge, so maybe another 81kWh of battery capacity added .....
Who would drive a luxury long range car further than that in a day?

T1 Terry