A materials company in Almeida, California, has worked over the past decade to accelerate the energy stored in lithium-ion batteries, which can enable a large range of small gadgets and electric vehicles in advance.
Sila has developed silicon-based particles that can convert graphite into anodes and capture more lithium ions than carrying current in a battery.
Now the company is bringing its product to market for the first time, providing a portion of the anode powder in the battery of the upcoming WHOP 4.0, which is fitness wearable. It’s a small device but potentially a big step for the battery sector, where promising lab results often fail to translate into commercial success.
“Think of Hoop 4.0 as our Tesla Roadster,” says Silla CEO Jean Berdishevsky, who as Tesla’s seventh employee helped solve some important battery challenges for the company’s first electric vehicle. “It’s really the first device on the market that is proving this success.”
The company’s content, with the help of other advances, has increased the energy release density in the fitness tracker’s battery by about 17%. That’s a significant gain in one area that typically goes beyond a few percentage points a year.
“It’s almost like four years of standard progress,” says Venkat Viswanathan, an associate professor of mechanical engineering at Carnegie Mellon University. “But in a big leap.”
Sila is still facing some real technological challenges, but advances are a promising sign for the possibility of increasingly capable batteries to help move the world away from fossil fuels to accelerate the risks of climate change. Increasing the amount of energy that batteries can store makes it increasingly easier to power more of our buildings, vehicles, factories and businesses.
For the transportation sector, more energy could reduce battery costs or expand the range of electric vehicles, addressing two of the biggest issues that have frustrated consumers leaving their gas guzler. It also promises to deliver grid batteries that can save more energy from solar and wind farms, or consumer gadgets that last longer between charges.
Energy density is the key to “electrifying everything,” says Berdychevsky, an innovator under the age of 35 in 2017.
In the case of the wearable new Fitness, the new battery material and other improvements made it possible to shrink the device to 33% while maintaining a five-day battery life for the Boston-based Hoop. The product is now so thin that it can be inserted into a “smart apparel” as well as worn like a watch. It will go on sale on September 8.
Silla, which announced ભ 590 million in funding in January, also has a partnership to develop battery materials for automakers, including BMW and Daimler. The company says its technology could eventually pack 40% more energy into lithium-ion batteries.
Berdychevsky took his job at Tesla before his senior year at Stanford University and took his job, where he was working towards a degree in mechanical engineering. He was instrumental in addressing the potential survival risk for the company: that a fire in any one of the thousands of batteries in the vehicle would ignite the entire pack.
He set up a program to systematically evaluate the range of battery pack designs. After hundreds of tests, the company developed a combination of battery systems, heat transfer materials and cooling channels that largely prevent fugitive fires.
After Tesla launched the Roadster, Berdychevsky felt he would have to take the opportunity to see the company through the development of the next vehicle, the Model S development, or to try something new.
In the end, he decided he wanted to create something of his own.
Berdychevsky returned to Stanford for a master’s program studying materials, thermodynamics, and physics in hopes of finding ways to improve storage at the basic level. After graduating, he spent a year as an entrepreneur in residence at Sutter Hill Ventures, exploring ideas that could become the basis of his own business.
During that time, they found a scientific paper identifying the method of producing silicon-based particles for lithium-ion battery anodes.
Researchers have long viewed silicon as a promising way to increase battery life, as its atoms can bind to lithium ions up to 10 times heavier than graphite. That means they have more than charged atoms that generate electric current in the battery. But silicon anodes tend to crumble during charging, as they swell to accommodate ions that shuttle back and forth between the electrodes.
This paper, co-authored by Professor Gleb Yushin of the Georgia Institute of Technology, highlights the possibility of developing a rigid silicone material with a porous core that can more easily absorb and release lithium ions.
The following year, Berdychevsky founded Silla with Yula and another former Tesla engineer, Alex Jacobs.
Interruptions and delays
The company spent the next decade working through more than 50,000 iterations of chemistry, modifying its methods and materials while increasing its production capacity. Initially, he decided to develop drop-in materials in which manufacturers of lithium-ion batteries could be exchanged, rather than adopting a more expensive and risky route to the production of a complete battery.
However, Silla is not as far away as she initially hoped.
After receiving several million dollars from the ARPA-E department of the U.S. Department of Energy, the company at one point told the research agency that its content could be in products by 2017 and in vehicles by 2020. In 2018, when Silla announced its deal with BMW, it said its particles could help power the German automaker’s EV by 2023.
Berdychevsky says the company now expects to be in “like 2025” vehicles. He says solving “last mile” problems was more difficult than he expected. Working with battery manufacturers to get the best performance from innovative materials involves challenges.
“We were sincerely optimistic about the challenges of scaling and bringing products to market,” he said in an email.
The Hoop News hints that Silla was able to engineer the particles in a way that gives safety, life cycle and other similar battery performance benchmarks achieved in existing products.