To solve the most urgent issues with electric car range, charging efficiency, and cost, General Motors is developing a number of next-generation battery technologies. These include silicon anodes, sodium-ion batteries, and solid-state batteries.
“Whether it’s all-solid-state, sulphide-based, oxide-based, or ceramic, our R&D team at GM has actively continued to look at solid-state technologies,” Kushal Narayanaswamy, GM’s director of advanced battery cell engineering, told InsideEVs in an interview last week. “Sodium ions are also being examined by our R&D team,” he continued.
In an electric car, the high-voltage battery is the most crucial and costly part. An EV’s acceleration speed and range are directly influenced by its voltage architecture and charging/discharging capabilities. EVs are still often more expensive than their gas-powered counterparts due to the high cost of the battery. In May, EVs typically cost $9,644 more than gas-powered vehicles.
In addition to lowering those expenses, automakers and battery manufacturers are attempting to enhance the safety, charging speed, and range of these cells in comparison to conventional lithium-ion cells. Despite concurrently researching next-generation combustion engines, GM is making a big commitment. GM is now the biggest cell manufacturer in North America, surpassing even Tesla, together with its primary battery supplier, LG Energy Solution. According to GM executives, it can manufacture cells more cheaply than its competitors.
With next-generation battery technologies, the manufacturer now hopes to expand its lead. In Warren, Michigan, Narayanaswamy is in charge of GM’s brand-new, state-of-the-art Wallace Battery Cell Innovation Centre. The facility debuted in 2022 and is situated just north of Detroit. It is the carmaker’s little-known tool for creating and expanding new chemistry and refining existing ones.
In the past, battery producers have provided cells to manufacturers, which were subsequently modified for use in automobiles. However, when Tesla brought battery development in-house in 2016 through its relationship with Panasonic, that model began to change. With greater control over every step of the process—from choosing raw materials to designing cells and integrating vehicles—GM is now doing the same.
GM’s work on the lithium manganese-rich (LMR) chemistry serves as an example. Prior to enlisting the help of its joint venture partner LG Energy Solution for mass production, the business constructed and tested 300 large-format cells in 18 different versions internally. According to Narayanaswamy, the Wallace Centre enables GM to develop internal expertise, prototype quickly, and scale more effectively with its suppliers.
Additionally, it allows the business more freedom to create and deploy large-format cells in a variety of forms and chemistries. Picking batteries off the shelf is giving way to a fully integrated, automaker-led innovation process. Because of its internal R&D capabilities and the seeming start-up-like latitude it has in battery research, GM is able to investigate alternative chemistries like solid-state and sodium-ion.
According to Narayanaswamy, GM is developing seven distinct anode and cathode chemistries, including the new LMR cells and several of its existing nickel-based applications.
The development of sodium-ion batteries is still in its infancy. Nevertheless, they are becoming more and more recognised as a viable low-cost battery substitute. Despite having a lower energy density than conventional lithium-ion batteries, they are far safer, don’t require rare earth elements, and are mostly immune to freezing temperatures.
Lithium is around 400 times less plentiful than sodium. According to a study that was published in the scholarly journal IOP Science, it is extensively accessible in our seas and oceans. Compared to lithium, which costs $5,000 per tonne, it costs $150 per tonne.
China’s JAC Yiwei 3, a small hatchback comparable in size to the BYD Seagull, was the first to use a sodium-ion battery in a production EV in 2024. On the CLTC cycle, its 23.2 kWh battery provides a range of 230 kilometres (142 miles). Early this year, the massive Chinese battery manufacturer CATL unveiled its first sodium-ion batteries for both high-voltage and low-voltage uses. The CLTC range of the high-voltage pack is 310 miles. It is said to function almost perfectly at temperatures as low as -40 degrees Fahrenheit.
In China, sodium-ion technology is particularly taking off in the electric two-wheeler market. In that class, the reduced cost and adequate performance for short-distance use cases outweigh the trade-off in energy density.
Regarding GM’s capacity to produce sodium-ion batteries, Narayanaswamy stated, “We do have the technical know-how.” “Getting the right supply chain and making sure the right application is there for it are more important,” he continued.
Solid-state batteries, on the other hand, promise greater performance and energy density than the majority of conventional chemistries.
The substance that moves ions between the charging and discharging cycles in a conventional lithium-ion cell is called the electrolyte, and it is usually a liquid chemical. Solid-state batteries replace that with a solid electrolyte, which is frequently composed of oxides, sulphides, or polymers. According to studies, this combination significantly boosts energy density, speeds up charging, and makes batteries safer and far less likely to catch fire.
Solid-state batteries are frequently referred to as the holy grail of battery technology by industry professionals. However, it has been difficult to scale the technology for mass production. Nevertheless, a few of automakers think that will happen anytime soon.
Solid-state batteries have already been included in prototype cars made by Mercedes-Benz and BMW. By the end of the decade, Toyota intends to make its first hybrid application, and Stellantis is anticipated to test one in the Dodge Charger Daytona the following year. In the meantime, a number of Chinese production EVs are already using semi-solid-state batteries, which substitute a gel-like material for the liquid electrolyte as a stopgap measure before full solid-state batteries can be manufactured.
Although GM has not yet confirmed that solid-state cells will be commercialised, the company has stated that the technology is being “actively explored” in its research and development laboratories.
Additionally, Narayanamswamy restated GM’s efforts on silicon anodes.
The electrode of an EV battery that stores lithium ions during charging is called the anode. Graphite usually makes up this substance. GM previously said that an EV’s charging performance and range can be enhanced by a larger silicon percentage. Although in very small quantities, silicon anodes have been used for a few years. Its percentage in the anodes is now expected to rise.
The carmaker is now evaluating large-format, automotive-grade silicon anode cells at the Wallace Research Centre in an effort to incorporate silicon anodes into its EVs. said Narayanaswamy.
When GM plans to introduce its innovative lithium manganese rich (LMR) prismatic cells on a production truck in 2028, the first results of its efforts at the Wallace battery centre will be visible. These cells will have a range of over 400 miles, save hundreds of pounds of weight, and reportedly cost about the same as LFP cells.
It might be some time before the other chemistries are deemed suitable for use in vehicles.
Regardless of the outcome on the policy front, where the Trump administration is working to eliminate almost all of the Biden-era clean energy initiatives, such as the EPA’s emissions standards, the consumer tax credits, and the manufacturing credits for EV battery plants, Narayanasawmy stated that the automaker will continue its R&D activities.
According to Narayanaswamy, none of those would hinder GM’s battery research and development activities.