Fremont, CA-based Amprius Technologies, Inc. has announced the shipment of the first commercially available 450 W·h/kg, 1150 W·h/L lithium-ion battery cells to an industry leader for a new generation of HAPS (high-altitude pseudo satellites). The leader in silicon anode lithium-ion battery cells with its Si-Nanowire platform says its high-energy-density cells have enabled groundbreaking capabilities in long-endurance, communications, and high-resolution imaging to cutting-edge stratospheric platforms since 2018.

Amprius says that the deployment of the industry-disrupting battery cell in an advanced aerospace application affirms it as the leading provider of the highest-energy-density cells available in the battery industry. The advancement from the 405 W·h/kg product, announced in November, “highlights the acceleration of our roadmap towards delivering products with unrivaled performance,” said Jon Bornstein, COO of Amprius Technologies. “Our proprietary Si-Nanowire platform and the comprehensive solutions we have developed enable unparalleled performance and continue to sustain our product leadership.”

The latest advancement is for a technology that has been in the commercial pilot manufacturing stage since 2018 at the company’s Fremont, CA, facility, but it is soon moving on to its first high volume manufacturing facility in the U.S., with a site to be selected in the first quarter of 2022. The move is a key step for the company led by Dr. Kang Sun, Chief Executive Officer, supported by Bornstein; Dr. Ionel Stefan, Chief Technology Officer; Sandra Wallach, Chief Financial Officer; Dr. Weijie Wang, Fellow; Aaron Bakke, Senior Director of Manufacturing; and Ronnie Tao, Vice President of Business Development.

According to Amprius, the main reason for the slow pace of battery improvement is chemistry. In conventional lithium-ion batteries, the anode is made of carbon in the form of graphite, and the company says that graphite has reached its energy-density limit.

It believes a new anode material is required to improve battery performance, and that material is silicon. It can store up to 10 times more lithium compared to graphite, which enables batteries to have much greater energy. However, silicon swells dramatically when it is charged with lithium, and that can cause it to crack and stop working.

In 2007, scientists at Stanford University discovered a solution to the swelling problem of silicon anodes, with nanowires shown to tolerate swell and resist cracking. Amprius has perfected this technology, and the result is said to be the world’s first 100% silicon nanowire anode for lithium-ion batteries.

Silicon nanowires are connected directly to the substrate with no binders so there is nothing to block the flow of current. The silicon lithium-ion batteries can substantially improve the performance of electric vehicles, aircraft, drones, and wearables, from almost doubling the range of a Tesla Model 3 with a long-range battery to providing nearly 2.5 times the Urban Air Mobility flight times.

The 100% silicon nanowire anode is a direct replacement for graphite anodes. The rest of the battery components and manufacturing methods leverage the established global supply chain for lithium-ion batteries.

In December, the company announced a charging rate of 6 min to 80% from 0% state of charge. It says the technological breakthrough validates its industry-disrupting performance against the USCAR’s U.S. Advanced Battery Consortium 2025 goal of 80% charge in sub-15 min and has been verified by a Mobile Power Solutions report.

“The need to shorten charge times extends well beyond the rapidly growing EV market and into the broader electric-mobility markets including micro-mobility and aviation,” said Bornstein. He added that the third-party validation confirms that the company’s Si-Nanowire platform delivers the highest energy density, power density, and now fast charging rate for real commercial applications.

The company’s proprietary Si-Nanowire anode is much thinner and lighter than conventional graphite anodes and has much higher conductivity due to the high electrical continuity between the silicon and current collector. The very low tortuosity of the anode structure also facilitates extreme fast charging, which is available on battery cells that are currently in commercial production and used in a variety of products including power-intensive drone and other aerospace applications.

In November, the company announced that it has secured commercial orders with Kraus Hamdani Aerospace, a pioneer in ultra-long endurance unmanned aerial systems (UASs). It started shipping battery cells to UAS maker through the end of 2021, and the companies have also entered into an agreement to secure additional high-performance battery cells through 2022.

“Amprius’ battery cells are the best in the market in terms of specific energy and energy density, both of which are critical for our unmanned aircraft that specialize in ultra-long endurance flights,” said Fatema Hamdani, Kraus Hamdani Aerospace CEO.

The Amprius cells will be used to power Kraus Hamdani Aerospace’s ultra-long-endurance UAS that has use-cases spanning defense, agriculture, communications, and emergency response. Compared with conventional batteries offering limited flight time capabilities at a heavier weight, they offer Kraus Hamdani’s aircraft double the energy in the same volume while also maintaining high power.

Amprius was also recognized with the Innovative Supplier Award at the 2021 Airbus annual supplier event, with Airbus Defence and Space choosing the company as the winner from over 10,000 suppliers. The company’s battery technology is used in the Airbus Zephyr solar-electric stratospheric UAS, which will be available to commercial, institutional, and military customers.

In December, Airbus and NTT Docomo, Inc. demonstrated the ability to use the solar-powered Zephyr HAPS (high altitude platform station) to deliver future wireless broadband connectivity. The trial took place in Arizona in August when the Zephyr S aircraft undertook an 18-day stratospheric flight to test various capabilities.

Based on a recent market study by Armstrong & Associates, the total battery market for UAS is estimated to be over $10 billion, increasing to over $30 billion by 2024.