The Shift to Solid-State Battery Technology is Next, Reports IDTechEx

BOSTON, Sept. 7, 2020 /PRNewswire/ -- Electric vehicles are expected to include solid-state batteries as an innovative approach, according to IDTechEx's research report "Solid-State and Polymer Batteries 2020-2030: Technology, Patents, Forecasts, Players".

The Mature Lithium-Ion Battery Technology Has Its Intrinsic Limitations

Since commercialized in 1991, lithium-ion batteries have received a worldwide success. However, this cannot hide their intrinsic limitations in terms of safety, performance, form factor and costs.

Most current lithium-ion technologies employ liquid electrolyte, with lithium salts such as LiPF₆, LiBF₄ or LiClO₄ in an organic solvent. However, the solid electrolyte interface, which is caused as a result of the de-composition of the electrolyte at the negative electrode, limits the effective conductance. Furthermore, liquid electrolyte needs expensive membranes to separate the cathode and anode, as well as an impermeable casing to avoid leakage. Therefore, the size and design freedom for these batteries are constrained. In addition, liquid electrolytes have safety and health issues as they use flammable and corrosive liquids. Samsung's Firegate has particularly highlighted the risks that even large companies incur when flammable liquid electrolytes are used.

Current high-end lithium-ion batteries can reach an energy density of over 700 Wh/L at cell level, with a maximum driving range of about 500 Km for electric vehicles. The high-nickel-cathode materials being improved may further push the energy density but the characteristics of the active materials may draw a threshold. 

Solid-State Batteries Can Be a Game Changer

Solid-state electrolyte enables the integration of better performed materials such as lithium metal and high-voltage cathode materials. However, it has been observed that the early-generation solid-state batteries may contain similar types of active electrode materials, with the liquid electrolyte being replaced by solid-state electrolyte. In this case, solid-state batteries have no obvious advantage over liquid-based lithium-ion batteries in terms of energy density.