File this one under gee whiz, or – if it pans out – file it under in a few years we won't be needing nearly as much gasoline to power motor vehicles anymore.

Stories of amazing tech possibilities come out all the time, but one reported last week with more than a little hope attached to it is about a lab-based experimental battery invented by MIT students based on a two-part liquid electrolyte called “Cambridge Crude.”

The battery is being developed for EVs and grid storage and reportedly could deliver more energy density than lithium-ion batteries while being more cost effective. Even more intriguing is it could overcome a common objection to present-tech batteries in that it can be “refueled” with the pump-able liquid as petrol cars do in minutes, thus promising to relegate long recharging times to distant memory.


Cambridge Crude. A new kind of black gold?

The project’s supervising professor, Yet-Ming Chiang – one of the founders of A123 Systems – said the team's mission was no less than "to reinvent the rechargeable battery," and he expects to have a fully operational prototype suitable for electric cars in the next 18 months.

The new battery, which you can read more about in a technical paper , has been licensed to 24M Technologies which is working on perfecting the recipe, as it were. This Massachusetts-based organization branched from A123 Systems – which itself branched from MIT – and is doing the research with $16 million in venture capital and U.S. Department of Defense funding.

According to MIT News, the battery employs an innovative architecture called a semi-solid flow cell. In it, charged particles float in a liquid carrier between two containers.

The battery’s electrically active components – the positive and negative electrodes, or cathodes and anodes – are composed of particles suspended in the liquid electrolyte.

These two different suspensions are intended to be stored in separate tanks in a vehicle, then slowly pumped through systems separated by a filter, such as a thin porous membrane. When they come in contact, they exchange ions and create electricity.

“[The] new kind of flow battery is fueled by semi-solid suspensions of high-energy-density lithium storage compounds that are electrically ‘wired’ by dilute percolating networks of nanoscale conductor particles,” MIT said in a summary statement.

The battery's separation feature is in contrast to conventional batteries in which energy storage and discharge take place in the same structure. Chiang said batteries can be designed more efficiently by separating these functions.

To recharge, electricity is input to separate the particles that make up each electrode. A couple potential ways to quickly “refuel,” would be either pumping out the expended liquid slurry, and replacing with fresh, similar to gas or diesel (except the pumping out part). Or, a complete tank swap system could be designed such as Better Place now proposes with solid batteries.

Until now, flow battery technology has been known, but energy density was too low. Cambridge Crude is said to have 10 times more energy density than previous liquid flow battery electrolytes. It is actually a fairly dense gel-like liquid that need not circulate very quickly, and instead “kind of oozes,” Chiang said.


MIT's "Cambridge Crude" flow battery.

The unique difference of the MIT design is that it utilizes proven lithium-ion chemistry broken into tiny particles merged into the liquid matrix.

The initial promise of Cambridge Crude's has MIT researchers hoping that they may have invented a completely new family of viable batteries.

MIT News cited Yury Gogotsi, distinguished university professor at Drexel University and director of Drexel’s Nanotechnology Institute who offered validation for the research.

“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.” This advance, he says, “has tremendous importance for the future of energy production and storage.”

Gogotsi cautioned research is still required to find better cathode and anode materials and electrolytes, but added, “I don’t see fundamental problems that cannot be addressed – those are primarily engineering issues. Of course, developing working systems that can compete with currently available batteries in terms of cost and performance may take years.”

This time estimate is on the high side from Chiang's year-and-a-half projection for a working prototype EV battery, so we shall see whether the optimists or pessimists win.

Source: The Atlantic Wire , MIT News , MIT Online Library