Sila Nano silicon anode for Mercedes EVs

In a significant step forward for the electric vehicle industry, Mercedes-Benz announced the next step in its partnership with Sila Nanotechnologies, to incorporate Sila's silicon anode chemistry in batteries for its upcoming Mercedes-Benz G-Class electric vehicles.

Aptly located in Silicon Valley, Sila Nano has developed a silicon-based anode battery technology that is expected to enable lighter, safer, and higher energy density batteries for EVs, longer-lasting portable electronics, and broader use and availability of renewable energy.

You can read more about Sila Nanotechnologies at Silicon battery tech firm raises $590M in the February 3, 2021, edition of Metal Tech News.

Utilizing the second-most abundant element on Earth, Sila Nano says its current silicon-based anode offers at least a 20% improvement over present state-of-the-art lithium-ion batteries with graphite anodes, in terms of energy density, with the potential to reach 50% improvement over time.

Scientists have long been searching for an alternative to the expensive and limiting lithium battery, with previous and current iterations using graphite as a cathode material, "which has too low an energy content to create battery cells with enough performance to be useful," according to some researchers.

This innovative silicon anode material, however, will purportedly increase the energy density of batteries without compromising safety or other performance parameters.

Compared to today's commercially available cells, Sila says its technology will enable a 20%-40% increase in the energy density, reaching more than 800 watt-hours per liter at cell level. This major development could allow Mercedes-Benz EVs to store much more energy in the same space, thus increasing the range of its future vehicles by a significant amount.

Mercedes-Benz previously invested in Sila in 2019, as part of the company's research and development of advanced batteries for the automaker's future electric vehicles.

The supply agreement announced May 17, is a natural step for the partnership and marks another important milestone in Mercedes-Benz' ambition to become the leading manufacturer of electric vehicles.

"Sila has come a long way since we established our strategic partnership in 2019," said Mercedes-Benz Group Chief Technology Officer Markus Schäfer. "They have been proving their ability to not only deliver scientific innovation at the highest level, but also their ability to manufacture high quality material. We're glad that in Sila we have a leading partner who will help us power our future generation of electric luxury vehicles with their highly innovative anode technology."

Such an achievement will surely be lauded, as the use of silicon in anodes for batteries has been a long-term goal of research for many decades.

Typically, although silicon nanoparticles have remarkably high capacity, they suffer from rapid degradation with each cycle due to electrode volume expansion of approximately 400% during lithiation – the process by which a lithium atom replaces a hydrogen atom – placing a large strain on the material.

Yet, with the earlier nearly $600 million investment and the backing of one of the world's most well-established auto-giants, it is evident there is some substance to a future lithium-silicon battery.

"The technology of silicon anodes have been around for years, in fact, silicon is used already in Tesla's vehicles with Panasonic as a cell manufacturer, but it's used in a very small percent, maybe 3 to 5%," said Kurt Kelty, vice-president of commercialization at Sila during an interview with Energi Media. "The reason you don't use more of it is, it suffers from swelling so when you charge and discharge, the silicon swells and then contracts and what we've been able to do is solve the swell issue, so our material doesn't swell any more than graphite would."

After over 10 years of research and development and 55,000 iterations, however, the Sila team is the first to industrialize and make commercially available a next generation lithium-ion chemistry with dramatically higher energy density using silicon.

"We're focused on delivering materials that are cost-efficient and capable of delivering on the promise of electric vehicles, working to ensure longer range energy, improved charge times, and lowering battery cost per kWh," said Sila Nano CEO Gene Berdichevsky. "To realize the potential of next-generation materials, scale up is a pivotal part of execution and we've been building towards automotive quality standards and scale since our start."

The production of the new anode materials will take place at Sila's new facility in Moses Lake, Washington, using 100% renewable energy. Additionally, Mercedes-Benz will be the factory's first publicly announced automotive customer.

"With our new plant in Washington, we're ensuring we can meet the requirements of our auto partners like Mercedes-Benz as they transition to a fully electric future," finished Berdichevsky.