DETROIT — Elegus Technologies Inc., one of the 10 startups that began a three-month accelerator program Techstars launched at Ford Field in Detroit this month, hopes the same material that helps stop bullets will lead to safer and more efficient lithium-ion batteries.
Aramid fiber is more typically used in range of applications for aerospace, the military and as an asbestos substitute. And, of course, for bulletproof vests.
Elegus' four co-founders think they have found another commercial use for the fibers: Increasing the time between charges for lithium-ion batteries and, more important, resolving one of the batteries' most widely acknowledged flaws: a dangerous propensity for overheating.
In 2006, Dell, Apple Inc. and Toshiba Corp. recalled a total of more than 6 million lithium-ion batteries powering notebook computers because of their tendency to overheat and sometimes even catch fire — eventually costing their maker, Sony, $250 million in replacement costs.
And in 2013, all of Boeing Co.'s new and long-awaited 787 Dreamliner aircraft were grounded because of fires ignited by lithium-ion batteries until stronger battery containment systems could be devised.
Lithium-ion batteries are also in thousands of hybrid and electric vehicles on the road today.
Elegus was spun out from the University of Michigan last August, a product of Nicholas Kotov's lab at the school. Kotov has an endowed chair in chemical engineering and is a professor of biomedical engineering, materials science engineering and macromolecular engineering.
Separating for safety
Elegus' plan: Use the fibers to help lithium-ion batteries keep a charge longer with less risk of overheating.
Three patents have been applied to cover its technology — which involves making extremely thin layers made of aramid fiber to separate the anodes from the cathodes in lithium-ion batteries.
Currently, lithium-ion batteries use thin layers of polyethylene for the separating layer.
The benefit of using lithium in batteries is it is the least dense metal, which means that, ounce for ounce, it can store more power than the metal used in other batteries.
But lithium is also a highly reactive element, a member of the alkali metal group that also includes potassium, another highly reactive element.
The trouble comes if a fault occurs in the separator, a rare occurrence but a dangerous one. That can trigger a short circuit called a thermal runaway that, in turn, can cause adjacent battery cells to overheat.
Dreamliners were allowed to fly again after the cells were given more protection from each other.
Tests at UM in Ann Arbor, Mich., show that batteries using aramid fibers as separators store up to 20 percent more energy, need less time between charges and remain stable at much higher temperatures than PE, said Elegus Chief Operating Officer Daniel VanderLey.
VanderLey said independent tests, which will be crucial to Elegus' commercialization plans, are scheduled to be conducted this summer by Navitas Systems LLC of Woodbridge, Ill.
He said Elegus has signed nondisclosure agreements with large chemical and battery companies to vet the technology. If tests by Navitas go as hoped, VanderLey said, Elegus will look for local manufacturers to make the aramid separators it will sell to battery makers.
The company plans forecast it will start production in the fourth quarter of 2017, generating $4.2 million in revenue that year based on the manufacturing of an estimated 2.4 million square meters of product.
VanderLey said the company hopes to produce 17 million square meters in 2020, with revenue of about $30 million.
"We're looking for an early exit to a chemical company after we prove out the technology," VanderLey said. "We'd liked to have an exit in the next two or three years for $20 million. But if that doesn't happen, we're looking at an exit to a customer in five years."
