Electric cars typically use lithium-ion batteries, which shuttle lithium ions between the electrodes. "Lithium-ion batteries have pretty incredible properties. They're very tuneable, so we can design them to fit a specific application through our choice of materials for the electrodes and the electrolyte," Dahn said. "Lithium-nickel-manganese-cobalt-oxide batteries (NMCs) are used in electric cars and come in a whole number of flavours depending on the performance you want."
Specifically, the nickel, manganese and cobalt are used in the positive electrode, and the precise ratio of these metals determines the properties of the battery. Car manufacturers must juggle lots of competing factors — including driving range, battery lifetime, weight and cost — to create the most appropriate vehicle for their customers.
Almost all NMC batteries use the same electrolyte and negative electrode. But chemists can tweak the battery properties further by adding special additives to these components. Tweaking chemical ratios can affect properties such as charging times and safe operational temperatures.