JAC Motors, a Volkswagen-backed Chinese automaker, unveiled the first mass-produced EV with a sodium-ion battery through its new Yiwei brand. Although sodium-ion battery tech has a lower density than lithium-ion, its lower costs, simpler and more abundant supplies and superior cold-weather performance could help accelerate mass EV adoption.
Probably because they’re new and the parent comment specifically referred to the cheaper, less energy dense battery types.