Adding silicon nanoparticles to the carbon-based anode of a lithium ion battery has been shown to dramatically improve battery performance. One company that is pursuing this technology is Paraclete Energy, which had an interesting start as a nonprofit. The company’s CEO, Jeff Norris, provided Design News with some exclusive insights into this silicon-based technology approach, its potential benefits for EVs, and where Paraclete came from and where it is going.
Design News: The use of silicon in the anode of lithium ion batteries is fairly new. Can you tell us how Paraclete got involved in this? How long have you been working in this field?
Jeff Norris: Paraclete Energy was initially formed as a philanthropic company in 2007 to produce very low-cost nanoparticle silicon inks for the room temperature production of very low-cost silicon solar cells and panels for third-world indigenous people groups. These silicon inks were made with covalently bonded, reactive functional organic and inorganic chemistry to the silicon surface to allow a much wider optical spectrum bandgap for higher photonic sensitivity. What is also relevant to the Li-ion battery industry is both Paraclete’s very low-cost production methods and the ability to make elemental nanoparticle silicon substantially oxide free.
This ability to produce cost-effective silicon nanoparticles at room temperature with nearly any organic or inorganic material covalently bonded to the surface of the silicon has been found to be very advantageous in overcoming the typical problems of working with nanoparticle silicon with Li-ion batteries. In 2012, in light of various events in the solar industry and the global move to electrify everything, Paraclete Energy focused on becoming a for-profit, sustainable supplier of nanoparticle silicon to the Li-ion battery industry.
|Jeff Norris, CEO of Paraclete Energy, will be a speaker at The Battery Show in Novi, Michigan, September 11-13. (Image source: Paraclete Energy)|
DN: What kind of advantages result in using silicon in the anode? How can these advantages improve the performance of the battery?
Jeff Norris: High capacity, cycle stable silicon in an anode enables greater range for an EV, the longer time between the need to recharge one’s phone, tablet, power tool, or other devices.
Graphite, the traditional anode material, cannot meet today’s high energy demands with a limited theoretical specific capacity of 370 mAh/g. Silicon oxide, which was used because it is air stable, has a higher capacity of 1,550 mAh/g. However, Paraclete Energy’s SM-Silicon is based on elemental silicon metal, which has a capacity of 3,590 mAh/g.
Like graphite, Paraclete’s SM-Silicon has a tap density of 0.8g/cm3 and an ICL of only 6% - 8% while being priced below graphite from a $/kWh.
DN: Fast charging has become the Holy Grail for EVs. Can silicon anodes help with that?
Jeff Norris: Fast charging is indeed not the Holy Grail, but a Holy Grail. Low cost and cycle-stable high capacity are also Holy Grails. Paraclete is presently working with some of the world’s leading fast-charging technology companies. We are assisting them by adding low cost and cycle-stable high capacity to their technology.