New solid state batteries from TDK
Just read this article about a new battery technology developed by TDK, an all-ceramic solid-state battery:
https://arstechnica.com/gadgets/2024/06/tdk-claims-insane-energy-density-in-solid-state-battery-breakthrough/
They claim an energy density of 1000 Watt hours per liter. By comparison, lithium ion batteries are 300 to 700 Watt hours per liter. Gasoline is 9700 Watt hours per liter, but internal combustion engines struggle to get efficiency above about 20%.
The solid-state design is claimed to be more durable and safer than existing batteries.
The article claims Toyota will be using them in vehicles by 2027.
No mention of how heavy they are.
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Replies
I'm pretty excited about solid state batteries. I hope they work, and I hope they end up making sense in cost/benefit.
LIB's just have such a huge fire potential. Very few LFP batteries fail, but when they do, the implications are large (larger than gasoline for instance).
In terms of vehicles, collisions with EV skateboard platforms often lead to LIB fires. (Not to mention the new norm of electronic door latches which has been my latest point of rant)
But let's also talk about home storage systems, and it's implications with that. Depending on the configuration, we can easily get into total battery capacity greater than vehicles. So have a collision into your home system with a car which is very feasible, and failure with thermal runaway becomes very serious.
Or otherwise, having your standard house fire is one thing to control, but if it gets into the garage where a LIB storage system typically is (if there is no garage, it'll probably be in the basement, which is way worse), it's now not a normal house fire anymore. Water doesn't put it out and it would be way harder to control or keep it to the one house, ie: neighbouring houses could catch on fire, etc. (based on lot sizes and seperation distances, fire ratings etc)
Solid state or otherwise non-flammable battery chemistry will hopefully solve all this. (I believe it will solve or reduce the potential of toxic gas emission from pre-thermal-runaway failure modes as well).
So Here I am crossing my fingers it comes out and financially makes sense sooner than later!
In the meantime, there's a LOT of lithium ion batteries, of various grades and quality getting pumped out into the general market, and will continue until solid state becomes cheaper.
For the point of discussion, these are my thoughts. Thanks for the high rant potential DC! Haha
Jamie
Solid state batteries have been just around the corner for the last 10 years. I'm hopeful that they are really getting close this time (and I know Toyota has staked a lot on it), but remember that claims like "up to 1000Wh/L" are leaning a lot on "up to".
I wouldn't be surprised if the first commercial offerings of them are comparable with LFP, since that will be the minimum viable product that their investors will be willing to bring to market. If they can increase that over the following years, great. The fact that they aren't available now shows that cost/stability/density isn't currently at LFP parity yet.
Another to watch is sodium-ion. These aren't as interesting for EVs (though some are being built with them in China), due to their lower density, but they are very interesting for home applications because of their higher inherent chemical stability, and wider operating temperature ranges. Right now offgrid homes are in a bit of a bind - lead acid batteries are very hard to permit in a home now, LFP works well but needs to be heated, LTO has great temp ranges but poor cost and life, and nickel-iron has good temp performance but poor voltage stability under load. Na-Ion could resolve a lot there and really open up home energy storage again.
Regarding fires, I do wonder what the actual incidence rates are of battery fires compared to other kinds of home energy storage such as generators, particularly liquid fuel generators. In automotive studies, results tend to show that ICE cars are 10-80 times more likely to catch on fire than an EV. Of course EV fires are novel, so they get more news coverage.
I'm not aware of any studies like this for homes, but I know that gas hot water heaters, gas ranges, and gensets catch on fire somewhat regularly, but they are a "known hazard" so get less reporting. If a Powerwall caught on fire you know it would hit the news. That is all to say that safer batteries and safer anything in our homes is always a worthwhile improvement, but I don't know enough either way to say if a home LFP battery is more or less hazardous than another form of home backup power.