A123 spinoff 24M funded for novel energy storage

Start-up 24M Technologies receives $10 million in venture funding to pursue high energy density storage for vehicles and grid storage that combines lithium ion and flow battery concepts.

Martin LaMonica Former Staff writer, CNET News
Martin LaMonica is a senior writer covering green tech and cutting-edge technologies. He joined CNET in 2002 to cover enterprise IT and Web development and was previously executive editor of IT publication InfoWorld.
Martin LaMonica
3 min read

Yet-Ming Chiang, the MIT professor whose research led to the creation of lithium ion battery company A123 System, and his colleagues have started a new company to address the limitations of today's rechargeable batteries.

Called 24M Technologies, the early-stage company on Monday announced that it has raised $10 million in a series A round of venture funding from Charles River Ventures and North Bridge Venture Partners. 24M Technologies also recently received a grant from the Department of Energy which will bring the Cambridge, Mass.-based company between $5.5 million and $6 million.

Yet-Ming Chiang MIT

The technology behind 24M came about when Chiang and collaborators at A123 Systems took a fresh approach to automotive and stationary energy storage, such as storing wind and solar power. It combines concepts in current lithium ion batteries with flow batteries, where tanks of liquid electrolytes combine to create an electrical current.

"It came out of taking a blank sheet of paper and looking at what the real limitations of lithium ion--and rechargeable battery technology, in general--are and considering future applications," said Chiang. "We came to a point where we felt that after two years' effort, it really had merit, we had digested the idea, and we had enough for a proof of concept."

A123 Systems is spinning out 24M Technologies as its own company to give it more attention, A123 Systems CEO David Vieau said last Thursday. Chiang will remain an MIT professor, maintain his position at A123 Systems, and work with the 24M team, which is now under 10 people. The technology was started at A123 Systems about three years ago and advanced in collaboration with MIT researchers.

In particular, 24M is trying to create batteries that can store more energy per volume than current lithium ion batteries. Chiang said it's hard to predict when a product will come to market but the company hopes to have its first demonstrations within five years.

One of the limitations with rechargeable batteries is the cost and overhead associated with inactive components, Chiang explained. Meanwhile, flow batteries, which typically have two tanks holding liquid electrolytes, are complex and require a lot of mechanical engineering.

Throop Wilder Crossbeam Systems

"What we're trying to do with the technology is to take the concepts from rechargeable batteries and high energy density flow batteries, and even fuel cells to produce a new device," Chiang said.

The Energy Department grant stemmed from an auto battery research program, but the technology could also be used for grid storage or other forms of stationary storage. With better energy density, a vehicle storage device could overcome the range limitations of lithium ion batteries.

Although it borrows flow battery concepts, 24M's planned device is not meant to be a flow battery, said company President Throop Wilder, a former networking technology executive. "A flow battery has been likened to managing a corrosive swimming pool," he said.

Both Chiang and Wilder were unwilling to be too specific about the technology or battery chemistry. A patent application, filed two years ago, describes a "high energy density redox flow device" where a semi-solid medium, such as a gel, is used for active materials. In an interview, Chiang said that the "storage media is flowable."

The name 24M refers to 24 molars, a level of concentration of active material in the storage media. "We believe that concentration is significant and relevant to the technology," said Chiang. "And we needed a name for the project."