Solid-state batteries, while potentially safer during external heating incidents (such as fires), are still vulnerable to short circuits caused by dendrite formation, as revealed by a recent study conducted by Alex Bates at Sandia National Laboratories. Surprisingly, they can ignite just as readily as traditional lithium-ion batteries.
What is a Solid State Battery?
Solid-state batteries replace the liquid electrolyte with a solid electrolyte. This solid electrolyte can be composed of various materials, including ceramics, polymers, or even hybrid combinations. The use of a solid electrolyte can potentially lead to higher energy densities, longer cycle life, and improved safety due to the reduced risk of leakage or combustion.
The term broadly refers to any battery using a solid electrolyte, so other chemistries besides lithium-ion can also be utilized in a solid-state configuration. However, lithium-ion-based solid-state batteries are currently the most researched and discussed due to their potential for high performance and safety in various applications, especially in electric vehicles.
Expert Insights on Battery Safety
Recent high-profile recalls and fire incidents have highlighted the dangers inherent to lithium-ion batteries. While generally stable under normal conditions, lithium-ion batteries contain highly flammable organic electrolytes and are susceptible to thermal runaway at temperatures as low as 60 degrees Celsius—a problem for applications with poor heat dissipation or use in equatorial regions.
Yuliya Preger, a Sandia researcher, stated:
“One of the promises of solid-state batteries is that they are safe because the solid electrolyte is firm and unlikely to break. But if it does break, the temperature rise could be about as much as when lithium-ion batteries fail…This study highlighted the importance of engineering the heck out of that separator so that it does not fail…We found if the solid-state battery has lithium metal, it has the potential to be dangerous.”
Are Solid State Batteries Safe?
Solid state batteries have not yet reached mass commercialization, so it’s impossible to say whether they will be safer in real-world applications. Researchers believe that they should be less prone to thermal runaway due to overcharging or internal shorts, but recent tests show that they may be just as flammable when crushed or punctured.
The Promise of Next-Generation Battery Technology
Several companies are currently developing next-generation lithium-ion solid state battery technology that substitutes liquid electrolytes for solid compounds, promising improved energy density and safety. While eliminating the liquid component is a step in the right direction, these batteries are still lithium batteries and have numerous safety issues.
Modern High-Performance Battery Alternatives
So how do we get from “safer” to “safe?” While better engineering will definitely go a long way to reducing the risks associated with current lithium batteries, a better option is to reduce the dependence on lithium altogether by using alternative chemistries that are inherently non-flammable. Life without lithium is possible, and with Alsym Energy’s new non-lithium battery technology, a safer future is here.
