Accelerating the Manufacturing Capacity of High Capacity, Long Life Silicon-Based Lithium Batteries in California
Silicon anode batteries with long lifetime for the next generation of lithium ion batteries
Rincell Corporation
Recipient
San Francisco, CA
Recipient Location
11th
Senate District
17th
Assembly District
$207,898
Amount Spent
Completed
Project Status
Project Result
In 2025, Rincell leveraged its Asia manufacturing and scaling experience to quickly ramp the LRIP line in Fremont, California. During equipment sourcing for the LRIP line, Rincell identified an opportunity to acquire equipments from a battery cell manufacturer that had entered bankruptcy. The equipments matched what Rincell had already specified and validated for the Fremont LRIP line. After confirming functionality and securing full support from the original equipment manufacturer, Rincell completed the purchase and rapidly integrated the tools into its Fremont facility.
Working closely with the equipment OEM and its established raw material partners, Rincell fully commissioned the Fremont LRIP line in December 2025 – approx. 6–8 months ahead of schedule.
In 2026, Rincell will start manufacturing its highest energy-capactiy 4.1Ah 18650 cells on the LRIP line. In addition, Rincell will use the LRIP line to provide battery cells as a service to several strategic raw material companies to drive material ecosystem development.
The Issue
With the push towards grid-storage batteries and electric vehicles to curb carbon emissions, a new generation of batteries with improved performance is required. Improvements to the capacity, energy density, and safety metrics of Li-ion batteries are restricted by the chemistry of their components. As an alternative anode active material, silicon offers a lighter and more compact cell design that can also support faster charging and better low temperature performance. However, silicon-based anode electrodes experience significant mechanical stress due to expansion and contraction of silicon particles during cell cycling which reduces cycle life. Silicon-carbon composites can address volume expansion, but their hard cell casing is unforgiving for even moderate stack-level expansion and gas generation and requires specialized electrodes. These advanced alternative lithium-ion battery chemistries also can be expensive to produce at scale.
Project Innovation
The purpose of this Agreement is to design and build a Low-Rate Initial Production (LRIP) pilot line to manufacture high capacity 18650 silicon-graphite anode lithium batteries with significantly higher cycle life compared to other silicon anode technologies. The batteries will be produced at an average rate of 500 cells per day and will have characteristics such as high energy density, fast charging, superior performance over a wide temperature range, and increased safety, and are based on raw materials less susceptible to supply chain disruption than mainstream graphite-based batteries.
Project Goals
Project Benefits
This Agreement will result in the ratepayer benefits of greater electricity reliability, lower costs, and increased safety by making high-capacity lithium batteries more affordable and accessible to Californians. The Recipient’s batteries have a higher capacity and energy density compared to traditional graphite-based batteries, allow faster charging of 0 to 80 percent in less than 20 minutes, and can perform at temperatures as low as -40C.
Safety: In addition to standard 18650 safety features (e.g., current interrupt device and top vent), the advances of engineered silicon materials (e.g., lower swelling) and judicial selection of cell components (e.g., separators with high thermal stability) provide additional cell-level safety features to mitigate thermal runaway occurrence. These safety characteristics—along with the battery’s high capacity and performance make the batteries more reliable for large-scale use.
Affordability
The project lowers costs by transitioning advanced battery technology from the prototype stage to a Low-Rate Initial Production (LRIP) pilot line, which drives down per-unit manufacturing expenses through process optimization and scale. Because these cells offer 10–17% higher energy density than current market standards, ratepayers benefit from a reduction in system-level costs, as fewer cells are required to achieve the same energy storage capacity.
Reliability
This project enhances electricity reliability by deploying battery technology with superior thermal stability and an industry-leading operational range down to -40°C, ensuring consistent performance across California's diverse climates. The increased cycle life of these silicon-carbon cells reduces the frequency of maintenance and replacement for energy storage assets, directly supporting a more resilient and dependable electric grid.
Safety
In addition to standard 18650 safety features (e.g., current interrupt device and top vent), the advances of engineered silicon materials (e.g., lower swelling) and judicial selection of cell components (e.g., separators with high thermal stability) provide additional cell-level safety features to mitigate thermal runaway occurrence.
Key Project Members
Jignesh Parikh
Dr. Jagjit Nanda
Dr. Lasantha Korala
Chris Kompella
Match Partners
Rincell Corporation
