Lithium-metal batteries have long been seen as the future of energy storage, but they've been plagued by one major problem: they tend to short circuit.
Now, researchers from Stanford University and the SLAC National Accelerator Laboratory have uncovered the root cause of this issue and offered solutions that could transform the energy industry.
Lithium-Metal batteries have several advantages over other batteries, including their high capacity, low density, and non-flammability. This makes them a promising option for electric vehicles and green technology.
However, despite their potential, these batteries have been held back by their tendency to short circuit due to tiny fissures in the ceramic electrolyte called dendrites.
In an effort to solve this mystery, the researchers conducted over 60 experiments to uncover the cause of dendrites in lithium-Metal batteries.
They found that small cracks in the ceramic solid electrolyte, which can be as narrow as 20 nanometers, occur when the battery is under pressure during fast charging. These cracks allow a lithium-Metal "bridge" to form between the anode and cathode, leading to a short circuit.
The researchers simulated a miniature battery using an electric probe and electrolyte to understand why lithium intruded into certain areas, causing a short circuit.
They discovered that any indenting, bending, or twisting, along with dust or impurities gathered during the manufacturing process, increased the chances of failure.
According to lead coauthor William Chueh, "Just modest indentation, bending or twisting of the batteries can cause nanoscopic fissures in the materials to open and lithium to intrude into the solid electrolyte causing it to short circuit.
Even dust or other impurities introduced in manufacturing can generate enough stress to cause failure."
The good news is that these findings offer a roadmap for engineers to overcome the limitations of lithium-Metal batteries. The researchers are now exploring ways to strengthen the electrolyte during manufacturing, as well as develop self-repairing coatings for the ceramic barrier.
In 2019, the same Stanford lab developed a method for lithium-Metal batteries to retain 85 percent of their charge after 160 cycles, compared to just 30 percent in previous reports. With this new information about the cause of short circuits, the possibilities for lithium-Metal batteries are endless.
In conclusion, the discovery of why lithium-Metal batteries tend to short circuit is a major breakthrough for the energy industry. It opens the door for engineers to design better, more efficient batteries that could revolutionize the way we store and use energy.