Lower Cost, Higher Density
“This is really about getting energy density in the right level. That’s the main thing,” says R. “Ray” Wang, principal analyst and founder at Constellation Research Inc., based in Palo Alto, CA. “Energy is everything.”
The high cost of battery ingredients such as lithium and other rare earth minerals, which are becoming rarer, creates one primary hurdle, Wang says. Mining rare earth minerals entails processes “more devastating than burning fossil fuels,” meaning “trading one evil for another evil” from a green perspective, Wang says. Instead, it’s essential to achieve greater energy density in more sustainable ways.
Manufacturing anodes using silicon offers a promising solution, he notes: “Different economics are in play” because silicon is a renewable resource, making the material “better for the environment in the long run.”
Other benefits include faster charging time (to 80 percent in six to 10 minutes), higher energy density, improved recyclability and longer life, he says.
The potential of so-called “bio batteries” also offers intriguing solutions, Wang says. Researchers at the Massachusetts Institute of Technology used a genetically modified virus to build nano-wire electrodes “that allow more electrochemical activity to happen” with less impact on the environment, he says. They contain a little bit of metal, such as palladium, which allows energy density that exceeds any kind of lithium battery now available, Wang says.
Other bio battery research focuses on enzymatic fuel cells, which use enzymes to break down sugar to create energy. The technology is rechargeable as well as biodegradable, he says.
Cell tech evolves
“Silicon anode is going to be our best bet for the next three to five years, and that’s going to power the revolution for the next decades — a 20-year run,” Wang predicts. Bio battery experiments won’t generate enough energy to make usable prototypes sooner than three to five years from now, and likely won’t be in production vehicles sooner than 10 years, he says.
“There’s a pretty big canvas of potential future [battery] cell tech” stemming from before 2014, when companies in the automotive and consumer electronics industries filed many patents that remain relevant today, says Evan Horetsky, a partner at the McKinsey Center for Future Mobility in Stockholm, Sweden, and the former director of engineering, procurement and construction at Tesla, responsible for the design and planning of Tesla’s Gigafactories in Reno, Austin, Shanghai and Berlin.
“The electric vehicle craze and others put pressure on the market for increasing the energy density, increasing the number of cells that can be made. So, as a result, the variations and innovations, as well as the scale of production, are going up” at a tremendous rate, Horetsky says — citing 50 percent year-over-year growth in factory production.
Today, nickel-rich chemistries such as nickel manganese cobalt (NMC) and nickel cobalt aluminum (NCA), are common in cell cathodes for benefits of higher energy density, power and charge-discharge rate. But “there has recently been a low-cost chemistry in lithium iron phosphate (LFP), mostly supplied by Chinese companies, that now takes more than 15 percent of the lithium ion battery cell market from the nickel-rich chemistries, Horetsky says.
Cell form factors also continue to evolve, Horetsky says. Most electric vehicles used pouch or prismatic before Tesla spurred a shift to cylindrical cells among battery pack designers. A new blade form factor, one of the latest new developments from BYD, offers a long cell that can span the entire length of a vehicle.
“That’s a bit fringe, but I think it’s going to develop” alongside more customized form factors, Horetsky says. “It’s definitely a lot less often that you change the form factor. What everybody is changing — and even a cell manufacturer might change a few times over the lifecycle of a production line — is the chemistry.”
The next step is solid state, which can be applied to cathodes, anodes and electrolytes, Horetsky says. In the case of the latter, ceramic or metal instance of fluid represents a “leapfrog technology” advance that also makes EV batteries safer in crashes. Still, manufacturers face incredible challenges to produce in high volumes on top of already challenging cell manufacturing, making the technology uncompetitive when it comes to price, Horetsky says. In McKinsey’s view, solid state batteries will achieve price competitiveness by 2030, when they could grab 70 percent market share over the next decade, he says.
Unconventional Architectures
André Taylor, professor of chemical biomolecular engineering at NYU Tandon School of Engineering in Brooklyn, NY, agrees that challenges for electric vehicle batteries center on capacity and reproducibility, and moving away from metals, especially lithium and those like cobalt that are sourced from conflict areas.
In 2016, Taylor’s Transformative Materials Devices Lab turned to heme, derived from hemoglobin, and used the iron it contains to produce a so-called “blood battery.” The heme serves as a redox mediator in a lithium air or lithium oxygen battery, added to a liquid electrolyte for improved ion exchange, he says.
Later, in 2019, the lab combined urea with waste asphalt from oil refineries to create anodes for high-capacity, low-cost, long-life sodium-ion batteries as an alternative to lithium-ion batteries. The technology also withstands rapid charging and discharging of the battery.
While those developments have not been applied to vehicles so far, they offer potential to do so, and his lab is now working torward that goal in collaboration with another national laboratory, Taylor says.
San Jose, CA-based QuantumScape, a company offering solid state batteries, is working on a lithium-metal, anode-free cell. Researchers there have replaced the polymer separator and liquid electrolyte used in conventional lithium-ion batteries with a ceramic solid-electrolyte separator and dropped the anode. (QuantumScape manufactures the battery without an anode, and the anode forms in situ on the first charge.)
“The size of the battery is shrunk dramatically [and] the ceramic electrolyte separator is really good at resisting lithium dendrites” that may cause a battery to short-circuit when charged too quickly, says Asim Hussain, the company’s chief marketing officer.
Replacing conventional graphite anodes with lithium metal, which can store almost 10 times more energy than graphite, improves the range performance.
“You can store more energy in the same amount of space” as a traditional battery cell — potentially providing 500 to 600 miles of range, rather than 250 to 300 miles with same-sized batteries, Hussain says.
QuantumScape’s battery technology powers a less-than-15-minute fast charge (from 10 percent to 80 percent) because lithium ions don’t have to travel as far and don’t encounter the obstacles posed by conventional graphite anodes. Fast charging every time in just 10 minutes — which is unrealistic for most consumers who typically only need fast charging on long road trips — would reduce the range slightly, he says.
QuantumScape’s largest shareholder, Volkswagen Group, has invested about $300 million into the company, which has developed the technology for more than 10 years and conducted more than 2 million tests, Hussain says. In December 2022, QuantumScape achieved its key public milestone for 2022, having shipped its first 24-layer prototype lithium-metal battery cells, which it refers to as ‘A0 samples.’ Also notably, QS shipped dozens of zero externally applied pressure single-layer pouch cells for customer testing for the consumer electronics sector in October 2022, as it seeks to apply its batteries to that sector.
Another EV battery innovator focusing on lithium ion technology hails from Alameda, CA. Founded in 2011, Sila conceived a silicon anode material that replaces graphite, bringing a 20 to 25 percent improvement in energy density and range compared to a same-size battery while maintaining the lifespan of 1,000 to 1,500 charge cycles required by automakers, says Kurt Kelty, Sila’s vice president of commercialization and battery engineering. The company’s technology is already in production in a consumer electronics product — the WHOOP fitness tracker — and Sila expects production volumes to be ramped up enough to satisfy automaker demand by 2025, Kelty says.
In May, the Mercedes-Benz Group AG (a Sila investor) announced a high-silicon anode battery from Sila as an option in a range-extended version of its upcoming electric G-Class SUV, expected to launch mid-decade. Sila will manufacture the advanced silicon anode materials for the battery at its new facility in Washington state, with Mercedes-Benz its first publicly announced automotive customer.
“Sila has come a long way since we established our strategic partnership in 2019,” Markus Schäfer, member of the board of management at Mercedes-Benz Group, and chief technology officer responsible for development and procurement, states in a press release about the launch. “Delivering such a high energy density is a true game changer and allows us to think in completely new directions when developing electric cars.”
NexTech Batteries, Inc., founded in 2016 and based in Carson City, NV, works with lithium sulfur technology licensed from the University of California at Berkeley, where it was developed in 2000. The company’s patented processes and materials incorporate a sulfur carbon composite, and yield a battery that holds more energy is lighter weight, safer, more environmentally friendly, and more cost efficient than competitive chemistries, says Warren Rapp, NexTech’s vice president of business development. Company officials are in discussions with major automakers in the U.S. and around the world, and its technology could be in a production vehicle in three years’ time, Rapp says.
“Battery technology is going to move faster now than ever before … because the need is there,” says Malcolm Bricklin, founder and CEO of Visionary Vehicles, based in New York — as well as the founder and CEO of Subaru of America in 1968, and of Bricklin Motors, whose historic SV1 car was introduced in 1974. “Solid state batteries are coming for sure, and they’re going to be coming very fast from now on, for sure. I predict that by this time next year, somebody will introduce a vehicle that has solid state batteries.”
Visionary Vehicles’ new cars — the three-wheeled Bricklin 3EV and extended-range 3EVX — will use lithium-ion batteries and offer ranges of between 250 and 380 miles. The company’s search for a manufacturer to build the cars remains ongoing, but a mid-2023 launch is planned, along with an eventual production ramp-up to 50,000 cars per month, Bricklin says.
