The Electric Mercedes-Benz G-Class SUV Will Use a Silicon-based Battery Developed by Sila Nanotechnologies

author: Eric Walz   

The electric G-Class concept.

Mercedes-Benz will use a more energy dense battery developed by California battery startup Sila Nanotechnologies in its upcoming electric G-Class from 2025, the automaker announced on Tuesday. 

The electric G-Class was first unveiled as a concept at the Munich Motor Show in 2021. 

The advanced battery for the electric G-Class SUV will use silicon-based anodes which are 20-40% more energy dense than comparable cells currently available, Mercedes-Benz said. These new types of batteries show promise in the auto industry, as they allow automakers to pack more and deliver more range in their future EVs. 

Sila Nanotechnologies is working to replace a battery's conventional graphite electrodes entirely with its proprietary and low cost silicon-based nanomaterials. The company has filed over 100 patents for its battery technology, which it has been working on for over a decade.

In Jan 2021, Sila Nanotechnologies announced it raised $590 million in Series F funding at a $3.3 billion post-money valuation. 

Silicon-based Nanotechnology for Electric Vehicle Batteries

Sila's advanced battery chemistry uses "silicon-based nanoparticles" for the high capacity anode material of lithium-ion batteries. These silicon nanoparticles replace the graphite in a battery cell's anode, allowing for the production of lower cost and more energy-dense battery packs, according to Sila. Silicon nanoparticles have almost ten times the theoretical energy capacity of the graphite materials most commonly used in lithium batteries.

The process also reduces swelling or expansion during charging. Traditional anode materials in EV batteries have a tendency to swell during charging, which can eventually cause damage to the battery and shorten its service life. But Sila Nano's silicon-based anode materials are porous enough to accommodate this expansion.

Silo Nanotechnologies says that its materials can improve the energy density of today's batteries by 20% and as much as 40% in the future as the technology improves, which translates into longer ranges for EVs.  But the technology can also make EVs more affordable in the future, with a smaller battery delivering as much power as a larger graphite-based battery.

"Delivering such a high energy density is a true game changer and allows us to think in completely new directions when developing future electric cars," Mercedes Chief Technology Officer Markus Schaefer said in a statement.

More importantly, Sila's silicon battery materials are designed to be a "drop-in" replacement for graphite in existing lithium-ion factories. The silicon-based anode coatings can be applied using the current lithium ion battery production process, making it possible to scale the technology using existing battery manufacturing lines.

The use of silicon-based anodes also improves "solid-electrolyte-interphase" (SEI) & cycle life. SEI is a process in which a microscopic coating forms on the electrode surfaces inside the battery from the decomposition of the electrolytes, which are created from repeated cycles of recharging and discharging. 

Although SEI is considered a part of a new battery's "break-in process," as it helps batteries maintain their charge, SEI formation is actually considered a defect of modern batteries, contributing to electrode surface instability, which leads to battery degradation over time.

Earlier this month, Sila Nanotechnologies announced the purchase of a new factory in Washington state where its plans to churn out advanced batteries for hundreds of thousands of EVs by 2026.

The 600,000-square-foot factory located in Moses Lake, Washington, will start producing automotive-scale quantities of Sila's silicon-based battery technology by the second half of 2024, with full production underway in early 2025. The facility will also produce advanced silicon-based batteries for consumer electronics.

The new facility in Washington state will serve Sila's existing joint ventures with automakers, Mercedes-Benz and BMW, as well as other partnerships not yet disclosed, according to Sila's co-founder and CEO Gene Berdichevsky. 

Berdichevsky is a former Tesla engineer who led the technical development of the battery technology for the Tesla Roadster, which was the company's first vehicle. According to TechCrunch, he was the seventh employee at Tesla and one of the first to successfully integrate a lithium-ion battery into an internal combustion engine vehicle, which was the Lotus Elise chassis that the Roadster was built on. Tesla produced the original Roadster from 2008 to 2012 before launching the Model S.

Berdichevsky left Tesla in 2008 and founded Sila in August 2011 with the goal of building lighter and higher energy density lithium-ion batteries to help spur the mass adoption of electric vehicles, as well as for broader use of renewable power sources. 

For the past decade, Sila has been working on its advanced silicon battery chemistry for EV batteries.  

In April 2019, Mercedes Benz acquired a minority equity stake in Sila as part of its research and development of advanced batteries for electric vehicles. 

Investing in more advanced batteries is an important part of Mercedes-Benz's electrification strategy and will allow the automaker to build EVs that offer much longer ranges. The automaker aims to have this new type of battery powering other electric models by 2025. 

Eric Walz

Originally hailing from New Jersey, Eric is a automotive & technology reporter covering the high-tech industry here in Silicon Valley. He has over 15 years of automotive experience and a bachelors degree in computer science. These skills, combined with technical writing and news reporting, allows him to fully understand and identify new and innovative technologies in the auto industry and beyond. He has worked at Uber on self-driving cars and as a technical writer, helping people to understand and work with technology.