Switching From Lithium-Ion Batteries To Lithium-Silicon Batteries
There are myriad paths to innovate lithium battery technology and not all the approaches envisioned are stable, commercially viable/scalable, produce improvements across all battery metrics, and/or are cost-effective. To date, the anode side of the li-ion battery cell has seen less innovation in adapting li-ion batteries to different needs than the cathode. However, anode innovation is where step-change transformation will take place. As of now, graphite has been the only reliable solution for the anode. Unfortunately, graphite as a stand-alone anode has significant limitations to its energy density and charge times that hinder the advancement of electric technologies.

To meet the growing tidal wave of demand for better lithium-ion batteries, global battery manufacturers need more than incremental improvements around the performance of graphite. They need a drop-in replacement that clearly exceeds the potential of graphite.

A long-standing goal for anode innovation with lithium batteries has been to leverage silicon as an active material inside of the anode, creating a lithium-silicon battery. Lithium-silicon batteries have the potential to hold huge amounts of lithium ions due to silicon’s 10x higher capacity than graphite. This quickly translates in cost parity for EVs and creates smaller, better lithium batteries for all electronics and energy storage. The idea is that a silicon-based replacement for graphite not only gives a massive boost to lithium’s performance and energy density within the battery but it also seamlessly fits into existing manufacturing processes.

By simply swapping out existing graphite anode material, drop-in-ready silicon-based technologies help minimize switching costs for manufacturing. They also eliminate the need for what could potentially be multi-billion-dollar manufacturing changes across different industries, and/or net new battery designs.

These new and improved silicon-based anode materials can immediately integrate into existing battery cell manufacturing lines to create better-performing batteries today, with no additional requirements for implementation at the cell level. True drop-in power provides three important characteristics:

Reduced reformulation work required during the initial validation and product development phases
Zero CapEx needed for retrofitting on the manufacturing line
Significant reduction in time to market for new products
Drop-in technology is a critical step to prove to the industry at large, customers, and financial markets, that a technology is easily manufacturable at scale and at a digestible cost from the first factory to all subsequent production facilities. The exciting potential of silicon-based battery anode materials, like our SCC55™, that are drop-in ready and manufactured at industrial scale, is that they create a step-change in what’s possible with energy storage. Lithium-silicon batteries move the world toward the electrification of everything because they are significantly more highly performing than li-ion batteries using graphite across all performance metrics. Lithium-silicon batteries have:

Higher energy density,
are faster charging than li-ion batteries using graphite, while
having comparable stability to graphite over 1000 deep-discharge cycles, allowing us to innovate things that we haven't been able to imagine before.
The basic reason for these performance improvements is simple—silicon can hold many more lithium atoms than graphite. One silicon atom absorbs four lithium atoms, whereas six atoms of graphite can only accommodate one lithium atom. Thus, silicon can hold 10x more lithium by weight than graphite. This allows for a much smaller anode in the cell, opening up more space for more cathode material (more lithium). It is the cathode that brings this initial lithium into the battery and so the more room enabled for the cathode - the more energy density possible. Replacing the low capacity graphite anode with a high capacity silicon anode delivers a revolutionary step-change in performance relative to the rate of battery improvement over the last 20 years.

The challenge with silicon chemistry up until this point has been that lithium ions inside of silicon can cause 3x expansion of the silicon, producing obvious problems of stability and mechanical stresses for batteries. If the silicon swelling problem could be solved for silicon-based anodes, the long-standing desire to use silicon would be achieved, helping usher in a new era of energy storage across sectors.

Group14 has solved the swelling challenge by creating a nanocarbon scaffold that acts as a host material for silicon and stabilizes the silicon during the lithiation (charging) and delithiation (discharging) processes. This innovation delivers greatly improved energy density and cycle efficiency for the lithium battery cells it lives in. When adopted, the lithium-silicon battery will replace the current lithium-ion battery, thus enabling the true electrification of everything today—not tomorrow.
https://group14.technology/en/whitepapers/transition-to-lithium-silicon-batteries-whitepaper