Hashim al-Mashat, Cyrus Rustomji, Jungwoo Lee, Joe Hinostroza and Jim Royer.

South 8’s Mission to Create Innovative Batteries for the Equitable Advancement of all People

March 04, 2020

Energy storage startup South 8 Technologies started in a hallway between two labs at the University of California, San Diego. Working out of this former storage space, South 8 founder Cyrus Rustomji was able to scrape together enough preliminary data on his novel battery chemistry concept to win some initial government funding and eventually launch a company.

Rustomji started working on South 8 full time in 2013 and was joined shortly after by Jungwoo Lee, who currently serves as the San Diego-based company’s chief technology officer.

Today, South 8 has grown to five employees strong and was recently awarded $150,000 from the California Energy Commission’s California Sustainable Energy Entrepreneur Development (CalSEED) Concept Award program to help accelerate the development of its battery chemistry.

“I never pictured myself doing anything like this, doing a startup. I just wanted to do a normal 8 a.m. to 5 p.m. job, get paid for it, and go home,” said Rustomji. “But when you create something you believe in and know that you would not be able to sleep at night if you didn’t try to push further, it motivates a sense of passion to pursue new goals.”

Based on Rustomji’s research, South 8 Technologies has developed a breakthrough liquefied gas electrolyte chemistry for next-generation lithium batteries that are capable of operating at a temperature range of -80 to +60 degrees Celsius – much wider than existing technologies. This novel battery chemistry could one day power new aerospace and defense technologies and serve growing markets for all-weather grid-scale storage and electric vehicles.

This innovative California-developed solution could one day bring affordable clean energy technologies to the masses.

“We started this company because we believe in the technology and wanted to do something good for the world,” Rustomji said.

>> Materials from Mars

Coming up with a new battery technology is incredibly difficult, which is why relatively few people attempt to do it. For South 8, it took bravery and a unique perspective to turn Rustomji’s wild idea into a company.

“We both saw the promise in this because we’re both terrible chemists,” Lee jokes. “We’re both physicists by training, which caused us to look at the battery field from a different perspective than everyone else and we saw the promise in a lot of materials that no one else does.”

While the rest of the battery industry has started to experiment with solid state electrolytes, South 8 went the opposite direction and created a gaseous electrolyte using a unique set of ingredients.

“These are materials you wouldn’t traditionally think of unless you lived on Mars, where temperatures are cooler and these materials are liquid instead of gas,” said Lee.

According to South 8, the liquefied gas electrolyte provides up to 80 percent greater energy than a traditional lithium-ion battery, while also increasing safety and lowering cost. An additional benefit is that South 8’s unique chemistry integrates seamlessly with the existing battery manufacturing process.

“Unlike other ideas in this space we have materials compatibility. We don’t need to reinvent the whole wheel – all anodes, cathodes, casings, etc., integrate seamlessly,” said Lee. “Manufacturers like the idea of exponential improvement without major disruptions.

>> CalSEED’s support changes the game

CalSEED was one of the first organizations to support South 8’s work. In 2017, the startup received a $150,000 grant from the CalSEED Concept Award program and has continued to gain momentum since then.

“[The CalSEED grant] really enabled us to kickstart a lot of the science,” Lee said. “It allowed us to buy materials and prototyping equipment we otherwise wouldn’t have access to.” 

“Plus, the network is huge!” she added.

Through CalSEED connections, South 8 went on to win additional funding from New Energy Nexus, as part of the LG Battery Challenge. CalSEED funding also helped South 8 secure grants from the Shell Game Changer program, California Energy Commission, Department of Defense, NASA and the National Science Foundation.

After going through the CalSEED process, “you’re more credible,” said Lee.

South 8 has raised about $3.3 million in grants, contracts and non-diluted funding since was founded in 2018 and is currently in the middle of a bridge round for an undisclosed amount.


Jungwoo Lee (front) and Hashim al-Mashat (back).



Jim Royer

>> The driving force behind “South 8”

Rustomji and Lee spend a lot of their time in the lab, thinking about how to create a better battery using innovative materials commonly found on Mars. But they also spend time thinking about how their battery solution could one-day serve their local community and others like it.

The focus in cleantech accessibility is backed into South 8’s name. Highway 8 separates wealthy North San Diego from blue collar South San Diego, which better reflects income levels in the United States overall. Rustomji and Lee decided to name the company after communities “south of highway 8” to remind themselves of why they started creating this new technology in the first place.

“South 8 Technologies is named as a reminder that as we develop these clean technologies, we do so for the betterment of all people, not just those that can afford it,” said Rustomji. “We all breathe the same air and our technologies can help reduce carbon emissions towards a greener future for all.”

While they’ve come a long way from the hallway Rustomji worked in, Lee noted that startup life can be stressful. But if South 8 is succeeds in bringing its breakthrough battery technology to market, it could dramatically reduce the cost of electric vehicles and grid-scale energy storage, and facilitate the transition to a low-carbon economy.

Running a startup “gives us amazing creative space to build something that we think could potentially change the world and bring some meaningful change to the whole energy infrastructure,” she said.

“So, if I’m eating ramen noodles, if that’s what it takes to do this work,” said Lee. “It’s worth it to me.”