Solid-state batteries (SSB) have emerged as a promising alternative. That’s especially to traditional lithium-ion batteries. With their potential for increased safety and higher energy density. For solid-state batteries are paving the way. That’s for advancements in electric vehicles and grid-scale energy storage.
In a recent study led by Sandia National Laboratories. Researchers challenged the notion that adding liquid electrolyte to SSB compromises their safety. Instead, they discovered that solid-state batteries with a small amount of liquid electrolyte can actually be safer. Moreover than their lithium-ion counterparts.
The Chemistry Behind Solid-State Batteries
Solid-state batteries operate on the same principle as lithium-ion batteries. That’s with lithium ions moving between the electrodes while electrons flow through the circuit. However, the key difference lies in the electrolyte.
In lithium-ion batteries, a liquid electrolyte facilitates the movement of lithium ions. That’s ensuring efficient battery performance.
According to Loraine Torres-Castro, a battery safety expert at Sandia, the liquid electrolyte can be likened to a fleet of cars shuttling lithium ions to their destinations. However, the flammability of current liquid electrolytes poses a significant safety risk, especially when batteries are damaged.
These batteries eliminate the need for liquid electrolyte by utilizing a solid material called a solid electrolyte. This solid electrolyte facilitates the movement of lithium ions, akin to a fleet of trains efficiently shuttling passengers to their desired locations. However, the challenge lies in the seamless transfer of lithium ions between the solid electrolyte and the electrodes.
Debunking Safety Concerns
One of the main criticisms of these batteries has been the safety implications of introducing liquid electrolyte. However, the Sandia research team sought to evaluate the actual safety risks associated with incorporating a small amount of liquid electrolyte into solid-state batteries.
The team conducted calculations to assess the potential heat release in three different scenarios: battery fires, dendrite formation, and solid electrolyte failure. Their findings were surprising. In the case of battery fires, solid-state batteries with a small amount of liquid electrolyte produced only one-fifth of the heat generated by lithium-ion batteries. Solid-state batteries without liquid electrolyte produced no heat in this scenario.
The second scenario examined the formation of dendrites, which can cause short-circuits in batteries. Regardless of the presence of liquid electrolyte, all three types of batteries produced similar amounts of heat, dependent on the quantity of lithium metal present.
In addition, the third scenario focused on the failure of the solid electrolyte. Surprisingly, solid-state batteries without liquid electrolyte exhibited temperatures. Those were similar to those of lithium-ion batteries. Especially when the solid electrolyte broke. This emphasizes the importance of engineering a robust separator within solid-state batteries. That’s most importantly to prevent such failures.
Balancing Performance and Safety
The study’s results highlight the trade-off between battery performance and safety. While solid-state batteries without liquid electrolyte are generally considered safer, the addition of a small amount of liquid electrolyte can significantly enhance performance without compromising safety. This finding paves the way for the commercialization of solid-state batteries, addressing one of their main obstacles: the solid electrolyte interface.
The team’s next steps involve conducting similar calculations and experiments with alternative solid electrolyte materials. By further exploring the engineering and safety aspects of solid-state batteries, researchers aim to accelerate their development and adoption in various industries.
Solid-state batteries offer a safer and more powerful alternative to traditional lithium-ion batteries. By replacing liquid electrolyte with a solid electrolyte, solid-state batteries eliminate the risk of flammability associated with current battery technologies. The recent study conducted by Sandia National Laboratories dispels concerns about the safety of adding a small amount of liquid electrolyte to solid-state batteries. These findings open up new possibilities for the commercialization of solid-state batteries, enabling advancements in electric vehicles and grid-scale energy storage. With ongoing research and engineering efforts, the potential of solid-state batteries can be fully realized, revolutionizing the energy storage landscape.