This is largely due to the use of lithium metal anodes, which have a much higher charge capacity than the graphite anodes used in lithium-ion batteries. At a cell level, lithium-ion energy densities are generally below 300Wh/kg while solid-state battery energy densities are able to exceed 350 Wh/kg.
The lithium-ion batteries that we rely on in our phones, laptops and electric cars have a liquid electrolyte, through which ions flow in one direction to charge the battery and the other direction when it is being drained. Solid-state batteries, as the name suggests, replace this liquid with a solid material.
Solid-state batteries may require even more lithium than current lithium-ion packs, exacerbating the limited global supply. Without effective recycling methods for solid-state packs, obtaining sufficient lithium resources becomes a concern that could hinder the widespread adoption of this battery technology.
Lithium-ion batteries work by letting ionic lithium cross the electrolyte barrier between the battery’s anode and cathode (the positive and negative ends). This electrolyte is a liquid in standard lithium-ion batteries. A solid-state battery uses a solid electrolyte to regulate the lithium ions instead of a liquid one.
Solid-state batteries can use metallic lithium for the anode and oxides or sulfides for the cathode, increasing energy density. The solid electrolyte acts as an ideal separator that allows only lithium ions to pass through.
A lithium-ion battery will typically have a graphite electrode, a metal oxide electrode and an electrolyte of lithium salt dissolved in some sort of solvent. In solid-state batteries, you might find one of a whole host of promising materials replacing the lithium, including ceramics and sulphides.
OverviewHistoryMaterialsUsesChallengesAdvantagesThin-film solid-state batteriesMakers
Between 1831 and 1834, Michael Faraday discovered the solid electrolytes silver sulfide and lead(II) fluoride, which laid the foundation for solid-state ionics. By the late 1950s, several silver-conducting electrochemical systems employed solid electrolytes, at the price of low energy density and cell voltages, and high internal resistance. In 1967, the discovery of fast ionic conduction β - alumina for a broad class of ions (Li+, Na+, K+, Ag+, and R…