Advantage of Prelithiation in Li-Ion Batteries

Before any Li-ion rechargeable battery has become functional for general use, it has undergone a lengthy process called formation. In this procedure, the battery is both charged and discharged in a very precise manner to control the initial chemical reactions with lithium. Many of these reactions are irreversible and permanently decrease the battery’s available energy. Moreover, this process requires expensive lithium to be part of the cathode. It significantly increases manufacturing time, and thereby the investment in plant and equipment is not leveraged to capacity. If one could reduce or eliminate this formation process, margins would increase, time to market would decrease, and the overall cost of Li-ion batteries would be reduced substantially.

“Prelithiation is very appealing,” Jeff Norris, CEO of Paraclete Energy said, “because, unlike many standard battery improvement techniques which fight for a fraction-of-a-percent performance increase, any percentage gain from prelithiation is gained as a 1:1 ratio towards overall battery energy density. Additionally, with adequate prelithiation minimal formation cycles that dramatically slow the production process down will be required, thereby cutting the time to manufacture batteries significantly which has a dramatic positive impact on reducing cost and an equal impact on increasing the total annual manufacturing capacity of the facility. Prelithiation should bring about a cost-reduction shift across the entire industry, or at least to those that embrace it.”

Researchers have tried to eliminate the formation process by adding extra lithium to the battery anode in this prelithiation process. One such electrochemical exotic method not adopted by industry is a method that involves building a pseudo-battery, charging it to a given capacity, isolating the battery anode and then building a new battery with the anode containing this extra lithium. This process adds additional manufacturing steps, as well as capital equipment, and uses inert atmospheres, all of which prevent commercialization.

Another exotic method that has also not been adopted by industry incorporates metallic lithium particles into the anode electrode. However, these lithium particles are incompatible with aqueous slurry mixing techniques and thereby pyrophoric so they must be applied after electrode casting/drying in a separate process. This increases complexity and costs, limiting widespread adoption.

Ideally, prelithiation must be compatible and safe to interact with aqueous slurry processing and not introduce additional processing steps. Paraclete Energy’s methods enables aqueous compatibility by preventing the violent chemical reactions typically seen with prelithiated materials.

Additionally, electrochemical cycling is improved given Paraclete’s SM-Silicon family of surface modified products acts as an artificial solid electrolyte interphase (SEI) limiting undesirable side reactions. This method can be fully compatible with aqueous slurries and does not add additional processing, making it the most logical approach to this coveted Li-ion battery improvement. Paraclete can manufacture tons of many types of nanoparticle silicon metal, our premier silicon product is SM-Silicon. SM-Silicon is an appealing anode material because its capacity, nearly 3,575 mAh/g, is ten times that of graphite.