RE:Lithium-Silicon EV Batteries Deliver Next-Level Performance An excerpt:
"There being no such thing as a free lunch, there is a problem. Silicon anodes expand almost 300% during the charging process, when lithium ions crowd in. When the battery discharges, the lithium ions make an exit, leaving the silicon anode to wither back down to its original size.
As a result of the stress, the anode eventually cracks and disintegrates, with a consequent impact on battery life.
Earlier iterations of new lithium-silicon technology managed to work around the problem, but then cost factors in as an obstacle.
“Many of the proposed silicon anodes that hope to tolerate the flow of lithium will require expensive starting materials and complex synthesis processes that use specialized equipment, making it challenging to produce at commercially relevant scales and costs,” PNNL has noted."
PNNL has developed a low cost solution based on a coating of carbon. Carbon also factors into the Group14 solution.
Group14’s flagship product is a silicon-carbon powder marketed under the trademarked name SCC55™, and they are not shy about listing the advantages.
“SCC55™ has five times the capacity and affords up to 50% more energy density than conventional graphite for Lithium battery anodes,” Group14 states. “Its unique hard carbon-based scaffolding keeps silicon in the most ideal form — amorphous, nano-sized, and carbon-encased. The result is the best-in-class anode material that exhibits outstanding first cycle efficiency and long life upon Li-ion battery cycling.”
Considering supply chain issues bedeviling the global economy, the big question is whether or not Group14 and other lithium-silicon stakeholders can churn out high volumes of SCC55™ at a fast clip.
That does not appear appear to be an issue. Group14 emphasizes that its technology is based on abundant and “non-exotic” materials. In addition, the powder is tailor-able depending on a customer’s needs, and it can be integrated into existing fabrication lines on a drop-in basis. That means willing customers can put the stuff to work when they receive it, rather than investing time and money to retool their lines.