EV storage breakthrough gets $1 million Energy department funds – low-cost batteries from CO2

  • Published on September 13th, 2017

The US Energy Department has been steaming full speed ahead on cutting edge energy storage technology, and the latest development is one of those environmental twofers we love. A $1 million grant from the agency will help a company called Saratoga Energy to bridge the gap between its labwork and a low cost, high efficiency energy storage technology ideal for electric vehicles — without the carbon footprint, too.

energy storage EVs batteriesBy Tina Casey

The EV carbon footprint

The Union of Concerned Scientists took a look at the lifecycle carbon footprint of EVs and determined that it is significantly smaller than conventional gas-powered vehicles.

However, EVs still have a carbon footprint, and in the interests of global carbon management that footprint needs to be as small as possible.

Part of the EV carbon problem is the graphite used in lithium-ion energy storage technology.

Graphite is a form of pure carbon chemically identical to diamonds but with different structural characteristics.

The carbon footprint of mining and processing comes into play for naturally occurring graphite, and the go-to source for synthetic graphite is petroleum coke (surprise!).

Local environmental issues also bedevil the graphite industry, but that’s a whole ‘nother can of worms.

Crossing The Valley Of Death

The Saratoga Energy solution is to skip the graphite supply chain middleman and go straight to the source: carbon.

The company came into the Energy Department’s Small Business Innovation Research grant program radar for a process that synthesizes graphite from carbon dioxide.

SBIR grants are doled out in stages depending on an awardee’s progress, so Saratoga must have a good trick or two up its sleeve. SBIR gave the company just $150,000 in the 2016 funding phase to help push the labwork along, so the new $1 million grant represents a big jump up.

The new funds are aimed at helping Saratoga cross the “Valley of Death” that separates cutting edge technology from the marketplace. In effect, we taxpayers are stepping up to bat for private investors who are wary of taking a chance on unproven technology. Group hug!

The Saratoga Energy Storage Solution

When you take a close look at Saratoga’s synthetic graphite technology, the potential for disruption in the EV marketplace is huge. Here’s the rundown from SBIR:

Graphite is the primary active anode component used in lithium-ion batteries and constitutes 10-14% of the total cell cost. In turn, the worldwide graphite market size for batteries is estimated to be $1.4 billion in 2015 making it a very attractive opportunity.

So far, Saratoga has compiled enough evidence to demonstrate that its CO2-to-graphite technology has the potential to provide for a 70% cost savings when stacked up against conventional graphite.

But wait, there’s more:

In addition, the company’s graphite features another very important characteristic: it enables fast charging of lithium-ion batteries — up to ten times faster than standard anodes. Thus, as the project succeeds, it will provide two essential contributions that are fully aligned with the mission of the DOE Vehicle Technologies Office: contributing to reducing the cost of batteries for electric vehicles and dramatically improving charging performance.

Phase I of the SBIR grant involved tweaking the fabrication process to optimize the performance of the synthetic graphite, and demonstrating the fast-charging capabilities.

Phase II will help Saratoga keep pushing down costs, with the aim of demonstrating the new process at pilot scale.

At that scale, Saratoga can produce more samples for potential customers to examine, while working on the design for the next step toward designing a full scale facility.

The pilot plant will also enable Saratoga to demonstrate lifecycle performance for its Phase 1 improvements in graphite performance.

To ice the cake, the basic process is powered by electrolysis, which opens the door for sourcing electricity from renewables.

The ice on that icing is another win for the environment: the carbon dioxide would be reclaimed from industrial waste gases.

So, make that a green four-for: lower cost, better performance, reduced carbon footprint and carbon sequestration, too.

How Does It Work?

If you want all the details about the process, you may have to dig a little because Saratoga is playing it pretty close to the vest.

Basically, it involves separating CO2 into oxygen and graphitic carbon through an electrochemical reaction.

That’s similar to other “splitting” processes, though the special sauce seems to be a tweak or two that makes the sequence deliver graphite rather than other forms of carbon.

Here’s an example of carbon separation example from MIT:

A molten salt electrochemical system comprising a eutectic mixture of Li – Na – K carbonates, a Ni cathode, and a SnO 2 inert anode is proposed for the capture and electrochemical conversion of CO2. It is demonstrated that CO2 can be  effectively captured by molten carbonates, and subsequently electrochemically split into amorphous carbon on the cathode, and oxygen gas at the anode…The intrinsic nature of alkaline oxides for CO 2 capture, the conversion of CO2 to value-added products, and the ability to drive the process with renewable energy sources such as solar power, enables the technology to be engineered for high flux capture and utilization of CO2.

Beyond EVs

Graphite plays many roles in the green energy future, so EV batteries is just for starters. Saratoga is already eyeing stationary energy storage applications.

Other uses noted by CleanTechnica include tricking out graphite with other materials is another promising pathway to cutting costs and increasing energy storage efficiency, so stay tuned for more on that.

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(Originally appeared at our sister-site, Cleantechnica. Check out their new 93-page EV report. Image: US Department of Energy.)

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