It has been quiet around the A123 spin-off 24M that had promised to deliver cheaper, semi-solid batteries by doing away with inactive materials in the electrodes. Now the company has received a 22 million dollar funding push and will build a small commercial plant beginning next year.
24M had started developing their novel batteries in 2010, backed by researchers from MIT. In 2015, they first made the news when presenting a new battery cell design using a semi-solid electrolyte, allowing for a much simpler design and thus cheaper production. Only it never materialised.
But now things seem to be moving again as M24 raised nearly $22 million in funding in a financing round led by the ceramics and electronics giant Kyocera Group and Itochu, a textiles and trading business. M24 will invest in further research and a manufacturing facility. Works on a small scale factory will begin with an industrial partner next year and they hope to deliver the first products in 2020.
For the process internally called SemiSolid, M24 uses electrolyte as the processing solvent and thus eliminates capital and energy intensive steps such as drying, solvent recovery, calendaring and electrolyte filling. In order to do so, they invented new cell designs, eliminating the need for significant inactive material such as copper, aluminium and separator.
For now, the lab-scale version of 24M’s batteries have an energy density between 280 and 300 watt-hours per kilogram (Wh/kg), exceeding the average 250 Wh/kg of most batteries now on the market.
In addition, Technology Review reports the company is also working on a different solution that could create lithium-ion batteries capable of reaching energy densities close to 500 Wh/kg. The company says they have already demonstrated that densities above 350 Wh/kg are feasible using this approach in the lab. But that relies on a very thick separator between the electrodes that would need to be scaled down to work on a commercial level, according to the report.