First Commercially Viable Solid State Battery From QuantumScape, Doubling Tesla's Wh-kg Ratio
By using a solid electrolyte instead of the typical liquid solution, solid-state batteries can store considerably more energy by weight and volume than lithium-ion batteries; but yet, making a battery that is reliable and has a useful life appropriate to any driver's needs - high charge and discharge rates, long service life, and without any temperature or safety concerns - has proven difficult up to now.
QuantumScape says it has solved the problem with a new design that uses lithium-metal anodes that are not formed during manufacturing, but formed around the current collector when the battery is charged. The energy density is reportedly excellent. In volumetric terms, the new battery can store 1 kWh/l, about four times what the current Tesla Model 3 battery stores. By weight, it offers between 380-500 Wh/kg, as compared to 260 Wh/kg in packages currently used by Tesla.
The QuantumScape battery charges at blazing speeds, allowing a 0-80% charge in 15 minutes. It can retain more than 80% of its capacity after 800 cycles, which would represent about 240,000 miles (386,000 km) traveled in an electric car.
Dr. Stanley Whittingham, co-inventor of the lithium-ion battery and winner of the 2019 Nobel Prize in Chemistry, stated in that regard that "… the hardest part of making a working solid state battery is the need to simultaneously meet the requirements of high energy density, fast charging, long life cycle, and wide operating temperature range. These data show that QuantumScape cells meet all of these requirements, something that has never been achieved before. If QuantumScape can bring this technology to large-scale production, it has the potential to transform the industry."
According to Venkat Viswanathan, a battery expert and professor of materials science at Carnegie-Mellon University, "… these results blow up what was previously thought possible in a solid-state battery. Withstanding a high enough current density to allow fast charging without forming dendrites has long been an industry holy grail."
Dendrites are tiny, rigid tree-like structures that can grow inside a lithium battery; their needle-like projections are called whiskers. Both cause tremendous harm; notably, they can pierce a structure known as the separator inside a battery, much like a weed can poke through a concrete patio or a paved road. They also increase unwanted reactions between the electrolyte and the lithium, speeding up battery failure. Dendrites and whiskers are holding back the widespread use of lithium metal batteries, which have higher energy density than their commonly used lithium-ion counterparts.
QuantumScape is an American company that does research about solid state lithium metal batteries for electric cars. The company is headquartered in San Jose, California and employs around 400 people. It was founded in 2010 by Jagdeep Singh, Tim Holme and Professor Fritz Prinz of Stanford University. In 2012, QuantumScape began working with German automaker Volkswagen.
In 2018, Volkswagen invested $100 million in the company, becoming the largest shareholder. In the same year, Volkswagen and QuantumScape announced the establishment of a joint production project to prepare for mass production of solid state batteries. In June 2020, Volkswagen made an additional $200 million investment into the company.
In September 2020 QuantumScape announced a merger with the special-purpose acquisition company Kensington Capital Acquisition. As a result of the merger, QuantumScape will receive $1 billion in financing, including funding from Volkswagen and the Qatar Investment Authority. At the same time, the company's shares will be listed on the New York Stock Exchange under the symbol QS. The transaction was completed in November 2020 and raised capital for the series production of batteries.
You can find more information and details on their website, www.quantumscape.com
All images courtesy of Tesla Inc.
Nico Caballero is the VP of Finance of Cogency Power, specializing in solar energy. He also holds a Diploma in Electric Cars from Delft University of Technology in the Netherlands, and enjoys doing research about Tesla and EV batteries. He can be reached at @NicoTorqueNews on Twitter. Nico covers Tesla and electric vehicle latest happenings at Torque News.