THE PROBLEM:
* There is an urgent need for high energy density batteries that will meet the ever-increasing needs of energy storage and enable our electric future.
* Lithium ion batteries (LIBs) offers a solution to this need leveraging the existing LIB manufacturing and commercial infrastructure that is not available for other types of advanced batteries. The overall LIB market for applications such as electric cars, drones, and smartphones is expected to grow from USD 37.4 billion in 2018 to USD 100.4 billion by 2025, at a CAGR of 17% . However, they suffer from the limited charge capacity at the anode electrode, which significantly hinders the energy density of the battery.
* Silicon (Si) is the best material in nature to create LIB anodes with a theoretical limit of 4200 mAh/g charge capacity (i.e. battery capacity; proportional to energy density), compared to the 372 mAh/g of currently used commercial graphite or ~740 mAh/g for graphene in research-grade LIBs. For example, the new 2170 Tesla batteries have 10% silicon generating 30% more energy density. It is the most abundant element on earth after oxygen and one of the lowest cost materials. It has been successfully used in solar cells with low manufacturing costs at large scales. On the other hand, Si faces substantial challenges such as:
- Swelling due to extensive volumetric expansion as it absorbs lithium (Li) ions during charging and corresponding contraction during discharging.
- This can lead to bre¬aking of the Si anode due to its mechanical rigidity and essentially short battery lifetimes.
* Nano-silicon can overcome the mechanical durability issues during LIB charging/discharging described above by providing available gaps for volumetric expansion/contraction acting like a spongy material. However, synthesis methods for nano-Si are typically complicated, labor-intensive, costly, limited to small-scale production, and involve toxic chemicals, also raising environmental concerns.
** Therefore, there is a need for scalable, low-cost, and environment-friendly fabrication methods for nanostructured silicon anodes to implement the use of Si in LIBs.
UNIQUE SOLUTION OFFERED by DEMAND:
Our patented technology allows us to modulate the density of silicon anode making it flexible and durable that leads to LIBs with superior energy densities and lifetimes. Our unique and simple synthesis method utilizes commercially available material fabrication systems, making it scalable for industrial production at high throughput and low cost, and does not involve any toxic chemicals. We achieved impressive charge capacity values of about 3500 mAh/g at initial charging/discharging cycles, and maintained a stable charge capacity of about 2000 mAh/g up to 300 cycles. A stable ~2000 mAh/g capacity achieved by our density modulated Si anode technology corresponds to an enhancement of approximately 5.4 times more charge storage capacity compared to graphite. In addition, having such a capacity up to 300 cycles is equivalent to ~1600 cycles of a conventional LIB, which overall significantly extends the usage time (A regular graphite anode battery would not be usable up to 1600 cycles.)
THE OVERALL OBJECTIVE:
The overall obective of the phase 1 project is to conduct technical, commercialization, practical, and financial feasibility studies involving producing Si-anodes, selling them to battery manufacturers, and/or nonexclusive/partially-exclusive licensing of the technology. Making and selling DEMAND anodes can provide a high profit margin, while licensing it to the battery manufacturers can lead to a fast commercialization of the technology. The results of our feasibility studies will better position us for the Phase 2 stage towards TRL9.
