GoKawiilSodium-ion batteries trail lithium-ion in energy density but gain industry backers
Sodium-ion and lithium-ion batteries both work by shuttling charged ions between electrodes, differing mainly in which element carries the charge. Sodium-ion cells deliver about 175 watt-hours per kilogram, well below lithium iron phosphate's 205 and lithium NMC's 255, partly because sodium ions are larger, heavier, and operate at lower voltages. Despite these limits, companies including CATL and the General Motors/Peak Energy partnership are pushing ahead with larger-scale commercial production.