Gridtential Energy, the bipolar lead battery start-up, has appointed John Barton, former president of global asset management for SunEdison, as its new chief executive. In an October 24 announcement, former Johnson Power Solutions’ global VP of product and advanced engineering Bob Gruenstern (pictured) was also named as a technology advisory board member.
Barton takes over from Christiaan Beekhuis, who has been with Gridtential since 2011.
Gruenstern joined JCI as an engineer in 1982 and retired from the firm in the summer of 2014. He presently works as a consultant to Interstate Batteries.
Gridtential said the appointments were made because of Barton’s experience in the sustainable energy sector and across global supply chains, and Gruenstern’s engineering knowledge.
The appointments follow the closing of its $11 million series ‘B’ financing round in September.
Barton said: “After my two decades of product development, high-volume manufacturing and solar, I believe we’re seeing the same intersection of technology advances, increases in performance and cost reductions in energy storage that catapulted those industries to the next level.
“This convergence is already transforming existing markets and enabling new ones, like the shift from 12 volt to 48 volt in hybrid cars.”
Ray Kubis, chairman of Gridtential, said: “Barton’s operations experience will help our battery partners move to high volume manufacturing of our silicon joule technology.”
In a silicon joule battery, silicon wafers are used as current collectors, replacing the lead grids used in traditional lead acid monoblocs.
In an interview with BESB, Gruenstern said he was on the brink of retiring when Kubis approached him.
“I’m a big proponent of lead-acid and when I heard about Gridtential I thought I’d like to see,” he said. “I didn’t expect it — you’ve got to have the right kind of technology and the right kind of market pull and when I went out on site with them I thought, they’ve got something unique that could solve the bipolar quest.
“The two major advantages are weight, because of the reduced amount of lead, and scaling up in voltage terms: the construction allows layers to be placed one on top of the other. This has always been a hurdle for lead-acid when it comes to 48 volts — you would have to use four lead-acid batteries and string them together with a cable connection. With this technology it can all be done in one unit.
“Once you’ve achieved voltage of six, 12, 24, it’s just a matter of adding more layers.”
Gruenstern said that when inserting the plates, although some of the manufacturing process has to change, often it meant eliminating some of the steps or modifying existing ones.
“In the end you are mixing and making lead-acid paste, assembling a battery, filling and forming the battery,” he said.
“I’d really like to see bipolar come to fruition. Lead acid has been that technology that has evolved maybe not in giant steps, but it always remains an attractive trusted solution. It’s great to see when it makes the steps to keep up with application changes.
“Lead acid has traditionally been excluded from a funding standpoint, but it doesn’t mean it hasn’t been trying to keep up and compete. Bipolar doesn’t have the energy density of power density of lithium, but it makes a good step towards it.”