Silicon Nanowires offer a 10x increase in anode capacity
Improvements in the energy density of lithium-ion batteries have diminished to less then 2% annually. Further advances require the use of new materials.
Although silicon has long been known to have greater than 10x the theoretical capacity of carbon (4200 mAh/g compared to 370 mAh/g), silicon could not previously be cycled successfully. Cycling inducing stresses in the materials, which historically have caused fractures and destroyed cycle life. For this reason, carbon has remained today’s anode of choice and improvements in the energy density of lithium-ion batteries have diminished to less than 2% annually.
Amprius has discovered that, structured as nanowires, silicon is able to swell without breaking, enabling the use of silicon as an anode material with high cycle life. Amprius’ development team has successfully demonstrated deep cycling of silicon over many cycles with minimal capacity loss.