The word "breakthrough" gets bandied about with alarming regularity. Anyone who performs science or covers it should know better than to use that phrase.
A rash of "breakthrough" stories appeared recently in conjunction with an announcement by privately held Envia Systems at the ARPA-E (Advanced Research Projects Agency) Summit in late February that it had achieved a world's record for energy density in a lithium-ion battery.
As we've recently discussed lithium-ion batteries in this space, and cited the conventional wisdom that only incremental improvements in their energy density are all that's expected in the near future, let's take a look at developments at Envia that caused a break-out of "breakthroughs."
(For context, see our recent piece, "Li-ion Batteries: One Path Clear, Another Less So." For more background discussion of related issues, see "Electric Vehicles: Rorschach Card for Election Year?" and "Interop and EVs: Work Remains.")
While we rarely pay attention to pre-commercial developments, Envia's work may be important for several reasons. One is the slower than forecast uptake of EVs in the United States. Another is the recent news concerning the scaled-back production the Chevy Volt, reflecting that slower EV market. Other reasons include the background noise created by reports of crash tests involving lithium-ion batteries that burst into flame and the apparent "bricking" of an EV battery in a Tesla Roadster.
All these factors underscore the importance of increasing the range of EV battery capacity, while reducing weight and cost.
Envia's work on Li-ion battery technology at this point is aimed solely at increasing the range of electric vehicles and bringing down their weight and cost. Those are the metrics that could move the needle on EV uptake. Full commercialization of Envia's apparent advancements is perhaps two to four years away, given that those advancements come in two steps involving both the battery's cathode and anode.
(In a discharging battery, the cathode is the positive terminal. In a recharging battery, the cathode is the negative terminal. These statements, in reverse, describe anodes.)
I had an opportunity to discuss Envia's work with two of its principals—Atul Kapadia, CEO, and Sujeet Kumar, co-founder, president and CTO. Kapadia and Kumar also discussed the sorts of metrics that market observers and investors should keep their eyes on that distinguish real advancements from hype in the EV battery sector.
"What Envia has done—which everyone considers a 'Eureka'! moment for Envia—has actually been a continuous evolution for the past four and a half years, since my colleague, Sujeet Kumar, started the company," Kapadia told me.
Lithium iron phosphate was supposed to solve all problems because it was very cheap, according to Kapadia. But energy density is what decides the cost of the cell. It is not the cost of the material only. (Energy density is the amount of energy in a system per unit volume.)
The conventional wisdom that Li-ion technology would see only minor, incremental improvements over time, according to Kapadia, is due to the tendency among vendors today to manipulate traditional materials in a minor way or blend them "to get a little more juice out of the apple." They also are working to make the passive battery elements lighter. They're not working on the active materials that could make a big difference in the key performance metrics, such as the cathode-anode electrolyte that governs the amount of capacity in each of those components.
So Kumar first explored the high-capacity materials for the cathode, which determines the energy density, and thus the cost, of all the most important elements in a Li-ion battery. ARPA-E was thinking similarly, thus a $4 million ARPA-E grant to Envia in 2009, followed by a $1 million grant from the California Energy Commission. (Envia, like many start-ups, is largely backed by venture capital, but General Motors has a stake as well.)
The result, after several years' work (i.e., the "breakthrough"): first, an HCMR (high-capacity manganese-rich) cathode, then a silicon-carbon composite anode. In the past few months, Envia engineers have assembled these components into 400 watt hours per kilogram (Wh/kg) cells. Wh/kg is an energy density metric.
"This was not something that happened overnight, through a brain wave," Kapadia said. "This was continuous hard work over the past four and a half years.
"The battery industry is subject to hyperbolic claims, so we've been conservative in our relationship with the public," he added.
That meant getting a nationally recognized, third party to asses Envia's work, which resulted in documentation that the company had achieved the world record of 400 Wh/kg cells. That could translate to a 300-mile EV range (triple current numbers) at half the cost of the battery pack.
Right now, Envia's components are being "qualified" by auto makers. The cathode innovation is 18 to 24 months away from commercialization, while the anode component is perhaps two years behind that schedule.
"Envia's goal is that 8 to 10 percent of vehicles on the road should be battery driven by 2018, globally, not including China," Kapadia told me. "The majority of vehicles on the road should be battery driven by the time Gen X is retiring. The only way to get there is to have all the components of a 400 Wh/kg battery commercialized."
As a privately held company, has some flexibility around its business model, which may include partnerships, licensing of technology, possibly manufacturing.
One frequently asked question: does this possible advancement have implications for grid-scale storage? Answer: Not yet. One thing at a time. But the higher capacity battery will hold greater value longer as its performance declines, providing strong secondary use value, either in a car or in a small-scale storage array.
Finally, in Kapadia's view, how does one assess the claims of battery innovators in a field characterized by hype?
He suggests that observers demand third-party validation, assess an innovator's customers, pay attention to the cell size (better than 20 amps is critical), assess cycling data (i.e., the number of charges/discharges possible in an automotive application) and the cost per kilowatt hour, which is difficult for third-party validation.
"Cost per kWh and customers are tied together," Kapadia added. "Customers won't come to you if your cost per kWh is not compelling."
Competition? Envia believes it will be disruptive to VC-backed research into different chemical mixes in the battery.
"If you want your battery in a car four years from now, you'd better have a 400 Wh/kg battery today," Kapadia said. "Once an OEM has created a profitable car in this manner, there is no compelling reason to continue to explore exotic technologies.
"In the lithium-ion field, we have some respected competitors, such as LG, Samsung and Panasonic," Kapadia concluded. "The aspiration of Envia is to commoditize this market and bring the prices down. We'd rather follow a model of partnering than competing. Profit maximization for Envia should not happen the Apple way—vertical integration, doing everything inside to get the biggest margins. We'll follow more of an Android, open-source model."
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