When it comes to battery innovations, the importance of production processes for bringing down costs is often overlooked. Now the MIT spinout 24M Technologies has simplified lithium-ion (Li-ion) battery production with a new design that requires fewer materials and steps to manufacture each cell. According to the company the design, which it calls “SemiSolid” for its use of gooey electrodes, reduces production costs by up to 40 percent. The approach also improves the batteries’ energy density, safety, and recyclability.
“The SemiSolid platform has been proven at the scale of hundreds of megawatts being produced for residential energy-storage systems. Now we want to prove it at the gigawatt scale,” said 24M CEO Naoki Ota, whose team includes 24M Co-Founder, Chief Scientist, and MIT Professor Yet-Ming Chiang.
Establishing large-scale production lines is only the first phase of 24M’s plan. Another key draw of its battery design is that it can work with different combinations of Li-ion chemistries. That means 24M’s partners can incorporate better-performing materials down the line without substantially changing manufacturing processes.
The kind of quick, large-scale production of next-generation batteries that 24M hopes to enable could have a dramatic impact on battery adoption across society — from the cost and performance of electric cars to the ability of renewable energy to replace fossil fuels.
The main components of batteries are the positive and negatively charged electrodes and the electrolyte material that allows ions to flow between them. Traditional Li-ion batteries use solid electrodes separated from the electrolyte by layers of inert plastics and metals, which hold the electrodes in place.
Stripping away the inert materials of traditional batteries and embracing the gooey electrode mix gives 24M’s design a number of advantages. For one, it eliminates the energy-intensive process of drying and solidifying the electrodes in traditional Li-ion production. According to the company, it also reduces the need for more than 80 percent of the inactive materials in traditional batteries, including expensive ones like copper and aluminum. The design also requires no binder and features extra thick electrodes, improving the energy density of the batteries.
“This is a platform technology,” Ota said. “We’re not just a low-cost and high-reliability operator. That’s what we are today, but we can also be competitive with next-generation chemistry. We can use any chemistry in the market without customers changing their supply chains. Other startups are trying to address that issue tomorrow, not today. Our tech can address the issue today and tomorrow.”
Judging by industry interest, 24M is onto something. Since coming out of stealth mode in 2015, 24M has licensed its technology to multinational companies including Volkswagen, Fujifilm, Lucas TVS, Axxiva, and Freyr. Those last three companies are planning to build gigafactories (factories with gigawatt-scale annual production capacity) based on 24M’s technology in India, China, Norway, and the United States.