Cell Design and Materials: Solid-State

SSB Hype vs Reality: Common Misconceptions Clarified Many expectations around solid-state batteries stem from simplified assumptions; real-world performance depends on system-level design tradeoffs rather than electrolyte choice alone. Common Misconception

What the Evidence Shows

“Solid-state” means all battery components are solid.

Many batteries labeled “solid-state” retain some liquid or gel components*. These are more accurately described as semi-solid or quasi-solid systems. Fully all-solid-state batteries remain less common and are still under development.

All solid-state batteries require lithium-metal anodes.

Solid-state electrolytes can be paired with graphite, silicon, or lithium-metal anodes. Lithium metal offers higher energy density but introduces additional interfacial and stability challenges.

Solid-state batteries inherently deliver the highest energy density.

Higher energy density is possible, particularly with lithium metal, but is not guaranteed. Some advanced liquid-electrolyte systems achieve comparable energy density today.

High ionic conductivity alone enables successful solid-state batteries.

While important, ionic conductivity is only one factor. Interfacial resistance, mechanical contact, and dendrite suppression are often the dominant challenges.

Solid-state batteries enable faster charging and higher power by default.

Many solid electrolytes exhibit lower rate capability than liquids due to interface limitations and transport constraints, particularly at room temperature.

* There is not an industry standard for ther term “solid’state”, although there is a new effort in China to create one.

Extracted from the PDF; charts and images may read imperfectly.