Battery manufacturing technology provider 24M has unveiled a new battery separator tech called 24M Impervio, which the company says can make EV batteries substantially safer by inhibiting the growth of dendrites (rootlike metal growths that can build up on the anode surface, potentially causing a short-circuit that can lead to a fire).
24M’s Impervio technology foils dendrites in two ways: a proprietary separator technology impedes the growth of dendrites; and the system continuously monitors each battery cell, and can detect a potential short before it occurs and shut down the individual cell. This could also prevent the mass recall of batteries by pinpointing defective products.
24M Impervio can be used in conventional lithium-ion and lithium-metal cells, as well as 24M SemiSolid cells.
24M’s internal testing demonstrated the Impervio cell’s safety advantages. In one test, the cathode of a baseline NMC/graphite cell and that of an Impervio cell were each intentionally contaminated with ~1% stainless steel. This caused the baseline cell to short immediately after dendrite formation, while the Impervio cell suppressed the stainless steel dendrite and surpassed 800 cycles.
In a second test, the baseline and Impervio cells intentionally exposed copper on the anode to stimulate the formation of a lithium-metal dendrite. This led to a rapid soft short of the baseline cell, while the Impervio cell suppressed the lithium-metal dendrite and delivered stable coulombic efficiency during cycling.
24M expects to demonstrate mass production of Impervio by the end of 2024 and introduce it to the market in 2025 or 2026.
“For many years safety challenges have limited the commercial viability of the most promising next-generation cell chemistries,” said 24M Chief Scientist Yet-Ming Chiang. “The ability to prevent dendrites and detect internal faults that 24M Impervio has shown can enable the commercialization of a new class of large-area, high-energy-density batteries based on lithium-metal and silicon-dominant chemistries.”
“The sweeping safety improvements demonstrated by 24M Impervio will open up a whole new world of growth for battery-driven applications by eliminating the fear of catastrophic safety failures,” said 24M CEO Naoki Ota.