New solid state battery data released by Volkswagen-backed QuantumScape has ticked three major boxes that could, if commercialised, blow away the capabilities of today’s electric car batteries.
Data released by the company on Tuesday (US time) shows testing of its single-layer solid state battery cells have a much higher energy density, as well as the ability to fast charge to 80% in 15 minutes, without degrading quickly.
They could also enable “hundreds of thousands of miles” to be driven without significantly degrading.
Co-inventor of the lithium-ion battery and winner of the 2019 Nobel prize in chemistry, Dr. Stan Whittingham, in a statement released by QuantumScape, said the data “holds the potential to transform the industry”.
Tesla co-founder JB Straubel who is on the board of QuantumScape alongside SolarCity CFO Brad Buss and Volkswagen execs Juergen Leohold and Frank Blome described the result as “a major breakthrough”.
QuantumScape CEO Jagdeep Singh told CNBC that QuantumScape’s end product would be about the size of a deck of cards, with the added benefit of being non-combustible.
“Today’s batteries are not competitive. They don’t have the energy density to get the range that’s needed. They don’t have the power to get the fast charge,” Singh was quoted as saying by CNBC. “Today’s best batteries take about an hour to charge where it’s obviously easy to re-fuel a gas car in 5 or 10 minutes.”
“The tested cells were large-area single-layer pouch cells in the target commercial form factor with zero excess lithium on the anode and thick cathodes (>3mAh/cm2), running at rates of one-hour charge and discharge (1C charge and 1C discharge) at 30 degrees Celsius,” the company stated regarding the test results.
“These tests demonstrated robust performance of these single layer pouch cells even at these high rates, resulting in retained capacity of greater than 80% after 800 cycles (demonstrating high columbic efficiency of greater than 99.97%).”
The data also shows that the solid state cells tested by the company can operate at a wide range of temperatures including down to -30 degrees Celsius – a temperature at which most solid state cells stop operating.
“The hardest part about making a working solid-state battery is the need to simultaneously meet the requirements of high energy density (1,000 Wh/L), fast charge (i.e., high current density), long cycle life (greater than 800 cycles), and wide temperature-range operation,” said Whittington.
“This data shows QuantumScape’s cells meet all of these requirements, something that has never before been reported. If QuantumScape can get this technology into mass production, it holds the potential to transform the industry,” he said.
For context, the 2170 Panasonic cells used by Tesla have a volumetric energy density of 711Wh/litre, according to InsideEV’s George Bower.
The cells tested were also able to fast charge at extremely high rates without the lithium dendrite formation that typically reduces the lifespan and performance of today’s EV batteries.
Increased energy density was achieved by avoiding the use of excess lithium on the anode, says QuantumScape.
A battery long life span, determined by more than 80% capacity retention after 800 cycles, has been made possible by elimiating the side reaction between the liquid electrolyte and the carbon in the anode of conventional lithium-ion cell, the company says.
“These results blow away what was previously thought to be possible in a solid-state battery,” said Venkat Viswanathan, battery expert and professor of materials science at Carnegie-Mellon University.
“Supporting high enough current density to enable fast charge without forming dendrites has long been a holy grail of the industry. This data shows the capability to charge to 80% capacity in 15 minutes, corresponding to an astonishingly high rate of lithium deposition of up to a micron per minute.”
“We believe that the performance data we’ve unveiled today shows that solid-state batteries have the potential to narrow the gap between electric vehicles and internal combustion vehicles and help enable EVs to become the world’s dominant form of transportation,” said Jagdeep Singh, founder & CEO of QuantumScape.
“Lithium-ion provided an important stepping stone to power the first generation of EVs. We believe QuantumScape’s lithium-metal solid-state battery technology opens the automotive industry up to the next generation battery and creates a foundation for the transition to a more fully electrified automotive fleet.”
In November, QuantumScape went public on the New York Stock Exchange via a reverse merger with special purpose acquisition company, or SPAC, Kensington Capital Acquisition.
The company’s shares jumped 31.08% on Monday (US time) to close at $US57.90 ($A78.07).
Bridie Schmidt is lead reporter for The Driven, sister site of Renew Economy. She specialises in writing about new technology and has been writing about electric vehicles since 2018. She has a keen interest in the role that zero emissions transport has to play in sustainability. She has participated in podcasts such as Download This Show with Marc Fennell and Shirtloads of Science with Karl Kruszelnicki and is co-organiser of the Northern Rivers Electric Vehicle Forum.