Semi-Solid Flow Battery, a Viable Alternative for Electric Vehicles

Researchers at the Massachusetts Institute of Technology have developed black goo for semi-solid flow battery that is lightweight and cheaper that existing batteries, which makes them a viable option for electric vehicles.

The black goo, dubbed "Cambridge crude", developed by the researchers overcomes the limitations of the traditional flow battery by providing a 10-fold improvement in energy density over present liquid flow-batteries and lower-cost manufacturing than conventional lithium-ion batteries. The Cambridge crude contains the battery’s positive and negative electrodes composed of solid particles that are suspended in the electrolyte liquid. In flow batteries, power is generated when an electrolyte is pumped through the battery’s systems separated by a filter. Traditional flow batteries use electrolyte liquids with very low energy density thus then need a large amount of liquid and large containers for the liquid. Because they take up so much space and have a lower efficiency, they are less popular than fuel cells.

The researcher’s new battery design reduces the size and the cost of a complete battery system, including all of its structural support and connectors, by half the current levels. The researchers said that this reduction could make E.V.’s competitive with conventional vehicles. "The demonstration of a semi-solid lithium-ion battery is a major breakthrough that shows that slurry-type active materials can be used for storing electrical energy," said Yury Gagotsi, a distinguished university professor at Drexel University. The researchers also pointed out that the novel flow battery which uses their goo can be scaled up to very large sizes at low cost. Since it can be scaled up, it can be used for large scale electricity storage for utilities making unpredictable energy sources such as wind and solar energy practical for powering the electric grid.

The development of the technology was partly funded by grants from the United States Department of Defense’s Defense Advanced Research Projects Agency and Advanced Research Projects Agency – Energy (ARPA-E). Currently, it is being licensed to 24M Technologies, a company founded by some of the researchers.