As the EV (electric vehicle) market continues to gain momentum, the development of better batteries is a key focus for automakers. The supply base is responding with new EV battery types, configurations, and chemistries. Innovations are coming from the entrenched players like Panasonic, CATL, SK Innovation, and LG Chem and especially from a growing number of new entrants like Quantumscape, Solid Power, Ionic Materials, and SES (formerly SolidEnergy Systems).

Boston-based SES has seen a lot of recent interest from the OEM and financial communities, as many industry EV experts see promise in lithium-metal batteries replacing conventional lithium-ion batteries due to the former’s higher energy density and greater safety.

 

Going public

The biggest SES news came this morning, as the company announced it was going public in a combination with its SPAC (special purpose acquisition company) partner Ivanhoe Capital Acquisition Corp. in what is believed to be the first publicly traded, hybrid lithium-metal battery supplier for EVs.

The combined company will be traded on the New York Stock Exchange under SES, with a proforma implied equity value of the combined company of about $3.6 billion inclusive of a $300 million earn-out for the transaction. The transaction is expected to provide SES up to $476 million in gross proceeds to fund expansion plans. This includes $200 million from a fully committed common stock PIPE (private investment in public equity), anchor investors including automakers General Motors, Hyundai Motor Co., Kia, Geely, and SAIC Motor. Other PIPE investors include the Koch Strategic Platform, LG Tech, Foxconn, and Fidelity Investments.

“As part of our diligence, we retained several of the world’s leading battery advisors to assess SES’s approach to li-metal batteries as well as commissioning independent third-party testing of the performance of its technology,“ said Robert Friedland, Ivanhoe’s Founder, Chairman and Chief Executive Officer. “We concluded that SES’s approach to Li-Metal batteries has led to it being the most competitive industry player today when measured by performance. This, together with its overall economics and wide-scale commercialization plan with key automakers, means that SES is the only next-generation battery technology company that will be successful in commercializing its batteries by the middle of the decade.”

Earlier this month, Korean news agency Yonhap reported that Hyundai Motor Co. would invest about $100 million in the lithium-metal battery startup.

In March, General Motors had announced a joint development agreement with SES. GM Ventures showed an early interest in the battery maker, with a 2015 investment being the start of a relationship between the two. The new joint development agreement is the next progression of the ongoing collaboration, with GM and SES planning to build a manufacturing prototyping line in Woburn, MA, for a high-capacity, pre-production battery by 2023.

SES also announced in April that it had completed its Series D funding round of $139 million led by the automaker, additional contributors including existing investors SK Inc., Temasek, Applied Ventures LLC, Shanghai Motor, and Vertex.

“This new round of funding will help accelerate technology development; significantly expand our technical, business, and manufacturing teams; and expedite the commercialization of lithium-metal batteries,” said Qichao Hu, Founder and CEO of SES, of the Series D.

“GM has been rapidly driving down battery-cell costs and improving energy density, and our work with SES technology has incredible potential to deliver even better EV performance for customers who want more range at a lower cost,” said Matt Tsien, GM Executive Vice President, and Chief Technology Officer and President, GM Ventures.

“We are pleased to be backing SES, which is making great progress in the next-generation battery development, and we believe it will bring meaningful change to the global EV industry,” said Yangtaek Kim, Executive Vice President of SK, Inc.

“SES’ lithium-metal cells have the potential to deliver a significant improvement in electric vehicle range compared to existing technology,” added Anand Kamannavar, Global Head of Applied Ventures.

 

Full-service solution

SES is aiming to offer the most complete solution in the highly competitive EV battery market, marrying its technology and mix of materials with a unique manufacturing approach. The company is developing lithium-metal cells because they deliver performance benefits sought by automakers and consumers including faster charging and a longer range at a lower price. It is optimizing its manufacturing process is optimized for affordable and easily scalable mass production.

Founded in 2012, SES was spun out of MIT from the Ph.D. research of Hu, who gave Futurride an exclusive one-on-one interview before the SPAC announcement. With strong capabilities in material, cell, module, AI-powered safety algorithms, and recycling, he says the company offers a unique full-service lithium-metal battery solution.

Helping him in the effort are Rohit Makharia, President and Chief Operating Officer, who was an investor in SES when he was at GM Ventures, but recently he joined SES full time. Key additional leaders are Yongkyu Son, Chief Technology Officer; Dr. Hong Gan, Chief Science Officer; Jing Nealis, Chief Financial Officer; Joanne Ban, Chief Legal and Corporate Officer; Hans Kim, Head of Korea; and Richard Chang, VP of Bus. Dev.

“We are not only producing battery materials but building a vertically integrated lithium-metal battery cell company, which provides a comprehensive solution that no one else in the market can offer,” said Hu.

A lot of battery companies are making similar claims about their battery solutions being faster charging, lighter, safer, smarter, and cheaper.

“But the key differentiator is [that] every claim we have made so far has been tested by GM, other car companies, and independent third parties,” he said. “Companies in the space will make some mathematical calculations and then just publish those estimates. In our case, every number we talk about, there’s an actual data point independently tested by third parties.”

The independent testers validating the SES claims are Eclipse Energy and Exponent.

 

Back to the future

SES claims its new ultra-thin lithium-metal system is a better solution than those using silicon-composite anodes, carbon anodes, and “old” lithium-metal solid-state alternatives.

A key benefit of lithium-metal (vs. lithium-ion) is its higher energy density, which has been a key driver of battery development since the first lead-acid battery came out in the mid-1800s. That was the case for the nickel chemistries—like nickel-cadmium and nickel-metal hydride—that came after lead-acid, and especially when Sony and Asahi Kasei commercialized the first lithium-ion batteries in the 1990s, enabling the age of laptops and cell phones. It was also true for EV battery makers when replacing carbon-based lithium-ion with silicon-carbon composites.

“In the seventies, the very first lithium batteries…actually used lithium-metal anodes, but back then they had a thicker lithium metal foil, so the energy density was lower,” said Hu. “And the electrolyte back then was very volatile and flammable. This is why Sony came out with this carbon lithium-ion anode, and then silicon graphite replaced graphite lithium-ion.”

Now the EV industry is heading toward lithium-metal, with car companies and battery makers around the world pursuing the next generation.

“The industry is going back to this old concept of using lithium-metal,” Hu said. “In the last 30 years, [there has been] a lot of progress in engineering, software, and materials. It wasn’t possible to make the ultra-thin lithium foils back in the ‘70s and ‘80s, but now it’s possible.”

SES has helped drive the advancements, developing the technology to make the ultra-thin lithium foil and new materials to make the electrolyte safer. The software has also come a long way.

“We have much more sophisticated software/AI that can very precisely monitor the data of the battery, so you can predict incidents,” he added.

 

Key enablers for better performance

Making thin lithium-metal foil is a recent engineering development, said Hu. Over the last few decades, the process has been optimized to roll thick into thin lithium and to thermally evaporate thin lithium for uniformity.

Battery-cell form factors are getting bigger, so the 10-micron (10-µm) thin foils are being produced in wide formats of around 500 mm (19.7 in) vs. the typical 100 mm (3.93 in).

Electrolytes have also gotten better.

“In the old days, we only had carbonate electrolyte, then a particular lithium-salt carbonate—an organic solvent that was highly flammable, highly volatile,” said Hu. “It was not compatible with lithium metal.”

Now SES uses a completely different solvent developed over multiple generations to improve efficiency and decrease volatility and flammability. The latest solvent is synthesized in-house using in-house materials.

Separators have advanced from the early days of simple porous polymer membranes.

“If you had dendrites, [they] would short through the separator, and then the cell would [fail],” said Hu. “Now the separator has ceramic fillers, so it’s much denser. You do coatings on the separator, so it’s also denser on the surface.”

Batteries have also improved through the application of software.

“In the old days, [you built] a battery, and then you were basically blind,” he said. “You had no idea if a battery was good or had a defect.”

The car is a very dynamic system, experiencing bumps and vibrations, but there was no monitoring of battery state-of-health. Now, with new software and sensors, key parameters of the battery can be monitored from the moment it comes off the manufacturing line.

“You know exactly the state-of-health of every individual cell, 24/7,” said Hu. “Then if there’s a small issue or micro-short, you can go through some healing charge and discharge cycles. If there is a major issue, then you send it back to the factory or repair.”

SES has developed AI (artificial intelligence) algorithms trained on terabytes of data to make batteries smarter, higher performing, and safer.

“We’ve built hundreds of thousands of these cells and collected data—chemical, thermal, and mechanical—and then feed the data into the model,” he said. “Going forward, the more that these batteries get used in actual cars, the more data we collect, and that translates to better training of the model, which will become more sophisticated.”

 

Coming soon

All these SES advances add up to impressive lithium-metal cell performance.

The company’s current battery system is capable of greater than 400 W·h/kg and 1000 W·h/L. This represents a major boost in energy density compared to today’s lithium-ion EV batteries at 280 W·h/kg and 700 W·h/L. As a result, the new technology can deliver significantly longer driving ranges for EVs.

The company’s cells can charge from 0% to 80% of battery capacity in just 15 min. They have demonstrated 500 cycles with 80% SOH (state-of-health) and a safety hazard level of less than 4. They use a low amount of cobalt of less than 7wt% and 11mol%.

The production version of the SES technology will hit the market in just a few years.

“Our partnerships with world-class automakers like GM, Hyundai, and Kia will further accelerate the commercialization of our technology and position our company to emerge as the leading lithium-metal battery supplier to more global automakers starting in 2025,” concluded Hu.