Electric Vehicle (EV) adoption is one of the most meaningful steps an individual can take to combat climate change. Yet, current battery performance is holding back many consumers from electrification. Beyond the issue of range, EV batteries are slow-charging, have short lifetimes, and are intrinsically dangerous systems. Adden Energy has developed lithium-metal solid-state battery technology that solves these issues. To scale production and bring this technology to car manufacturers, the company has raised $15M in a Series A round led by At One Ventures.

“Current EVs work great for people like me – those with at-home charging whose driving consists of short commutes and an occasional road trip,” explained Adden Energy Co-Founder and CEO Will Fitzhugh. “That’s not good enough. We need to deliver battery solutions that put EVs at parity with the internal combustion engine in every consumer facing dimension.”Slow charging limits EV adoption amongst the over 120 million Americans who live in housing without dedicated parking, making at-home charging impossible. Commercial vehicles routinely drive over a million miles in their lifetime, far beyond what lithium-ion batteries can deliver. Safety concerns regarding the high flammability of current batteries limit EV adoption across the board.

Adden Energy’s next-generation batteries are on track to reach the ambitious goal of EV parity with internal combustion engines by 2028. Based on solid-state battery technology originally developed at Harvard, Adden Energy combines two technologies that have long been goals of the EV industry – lithium metal and fast charging.

Lithium metal has the highest energy density of any battery material, offering longer driving range and lower costs than current batteries. That promise has so far been unachievable due to lithium metal dendrites, microscopic strands of lithium metal that grow through the battery causing catastrophic failure. Dendrites are particularly dangerous at high charge-rates as high current causes faster, more aggressive dendrite growth. In 2022, Adden Energy was spun-out of Harvard to commercialize new tech that stops dendrite growth entirely.

“Every battery has some level of imperfection – or defects – which dendrites can use as an avenue to grow. For example, dendrites can grow along microscopic cracks in the battery components,” explained Harvard Professor and Adden Energy Co-Founder and Chairman Xin Li. “Rather than trying to make perfect batteries with no defects, which is practically impossible, we’ve figured out how to make components that self-heal dynamically while the battery is in-use, a phenomenon that has been studied for years and nowadays can be designed by us. This allows the battery to stop dendrites in terms of both manufacturing defects and any damage to the battery that happens during its useful lifetime.”

The self-healing solid-state separator, originally discovered at Harvard and exclusively licensed to Adden Energy, not only allows lithium metal with no risk of dendrites but also enables the battery to be pushed beyond the limits of traditional batteries. Adden Energy’s prototypes are the fastest in the world, charging in less than 10 minutes with nearly 10x the lifetime of conventional batteries.

The funding, led by At One Ventures with participation from Primavera Capital Group, Rhapsody Venture Partners, and MassVentures, will be used to construct a roll-to-roll pilot line production facility at Adden Energy’s headquarters in Waltham, MA. The company has already demonstrated technology that can deliver the world’s fastest lithium metal battery in EV-compatible, commercially acceptable pouch cell form-factors. This Series A funded production line will enable them to scale the size of the batteries 100x.

“We are in the middle of an exciting transition from a fossil fuel economy to a materials economy, but we haven’t yet maximized the productivity of the materials used in EV batteries,” notes Laurie Menoud, Partner at One Ventures and board member at Adden Energy. “Our investment in this technology is a signal of how important we know this to be, and it’s also our confidence level in Adden Energy’s ability to win market share through competitive unit economics. With the added energy density of lithium metal anodes, the cost per kilowatt hour is going to drop by 30%, and that is going to be a significant driver of adoption.”

The development of this technology, and Adden Energy’s position as a battery manufacturer, comes at an ideal time, with several federal and state initiatives underway to boost American competitiveness in the space. The Inflation Reduction Act and the Bipartisan Infrastructure Law both aim to repatriate the battery manufacturing industry. Adden Energy is an opportunity to make sure that that manufacturing is for next-generation technology. The company has already received support from both the federal government and the State of Massachusetts.

“Adden Energy is a great example of the type of cutting-edge climate tech innovation that is coming out of Massachusetts,” said Economic Development Secretary Yvonne Hao, Chair of the MassVentures Board. “A spinout from Harvard University, MassVentures provided early support as an idea evolved into a commercialized technology with huge potential for our transition to clean energy. We’re so grateful to have Adden Energy in Massachusetts and we are eager to see the company grow and scale here.”