When you think about the evolution of cars, you think of naturally aspirated V12 engines, flat sixes, and everything in between. To most, electric cars seem like an innovation of the present and future. However, the first four-wheeled electric car was created in the late 1880s by Andreas Flocken. Due to power density limitations of the time, internal combustion engines were deemed the powerhouse of the 20th and early 21st centuries. By contrast, this cycle is reversing itself today, with the limitations of internal combustion engines pushing forth an engine of the future which isn't an engine at all. It is a battery. Just like how different engine architects shaped eras of automotive history, the materials that go into batteries will shape the next.
Many have seen the disturbing videos of Teslas catching fire in their garages, or have been angered by the realization that their battery-powered cars have severely restricted range. Hence, solid-state batteries have been marketed as the holy grail of EV technology. Unlike the lithium-ion batteries used by leading electric vehicle manufacturers such as Tesla, solid-state batteries utilize solid materials that enable high energy density, faster charging, and increased safety.
The main attraction of solid-state batteries is the advantages of packaging. You cannot indefinitely increase the energy density of a lithium-ion battery due to the dangers of compressing highly volatile liquids within the battery. However, solid-state batteries utilize a solid electrolyte instead of a liquid electrolyte, enabling a different anode with a higher storage capacity.
While solid-state batteries are more expensive than lithium-ion batteries, if mass production and innovation continue, the adoption of solid-state batteries would enable longer ranges and innovation without exponential price increases due to their simpler system and less expensive components.
For now, speculators claim that solid state is coming, but not as soon as headlines suggest:
Cost: The specialized materials and manufacturing processes are far more expensive than conventional lithium-ion.
Scaling: Even if a prototype works, building gigafactories to mass-produce them is a different challenge entirely.
Durability: Cracks in solid electrolytes and uneven wear make long-term reliability questionable.
Through all of this turmoil, the significance of material science becomes apparent. Companies must bet and invest in what they feel is the true future, whether it is a variation of the lithium battery, sodium, or solid-state. Material science will affect not just the chemistry, but also the durability, scalability, safety, and engineering trade-offs. In the same way that carbon fiber defined supercars, the material inside tomorrow's batteries will define the entire industry.