Coretec Group Inc (CRTG)

[Quikshft]

This article is going to take some time to read. Still working through it and even though it is from 2018 is seems quite relevant, describing Si (silicon) anodes and designing an SEI layer. The later is a little disappointing when you understand that the 'engineering' of an SEI layer is probably not a new concept and certainly not the unique domain of Coretec. Hopefully their vein of research will lead to a unique solution, and the Endurion battery will realize much greater energy density that even the Amprius battery which is a 2x over a unit with graphite anode.

Here's a paste of some relevant info from the article, you'll recognize a few familiar terms and/or concepts:

The SEI on graphite can provide acceptable life in commercial Li-ion batteries, even though more than 50% capacity loss in a well-engineered LIB can be attributed to the SEI growth. In contrast, SEI design faces more challenges for the development of high-capacity anode materials. For example, the SEI is unstable for an anode material like Si after repeated cycling due to the large volume change accompanying its high capacity. The large volume change induces SEI damage, leading to low Coulombic efficiency. Nano-structured Si can avoid Si fracture, but because of the high surface area, it must be optimized along with a chemically and mechanically stable SEI in order to avoid SEI mechanical–electrochemical degradation and to achieve high Coulombic efficiency.

Link:

https://www.nature.com/articles/s41524-018-0064-0