By coating the iron sulfide cathodes in polymers, a research team was able to create transition-metal sulfide-based lithium batteries with stable cycling and high safety. After 300 cycles, a lithium carbide iron disulfide pouch cell retained 72.0% capacity with no capacity degradation after 100 cycl...
I really like the safety aspect of this, but 72% capacity after 300 cycles seems low. What's a use case scenario where this is preferable over lipo batteries?
Much more stable chemistry. In stationary applications, like UPS systems and off grid electrical systems, lead acid is still the standard, due to having stable chemistry, very unlikely to catch fire, and a cost to capacity ratio that is still very good.
The degradation seems pretty bad, but if it's stable from 300 cycles onwards, you could take 75% as the actual capacity of the battery.
As a point of reference, Google says that somewhere between 500-2000 cycles you can expect a regular lithium battery to degrade to 80%. So this is worse, but in the ballpark. Seems reasonable for a research prototype to be a little worse than a commercial product that’s had years to become highly optimized.
One of the fabricated battery pouch cells was even able to work after being folded and cut off. “That proves its high safety for practical application,” the researchers emphasized.
If you can cut it in half and it still works I doubt piercing it will do much.