Lithium-sulfur battery technology breakthrough may extend electric vehicle battery life by 4 times

According to foreign media reports, researchers from the University of Texas at Austin and the Cockrell School of Engineering have found a way to stabilize one of the most challenging parts of lithium-sulfur batteries and accelerate the commercialization of lithium-sulfur battery technology.

Recent research results from researchers at the two American universities indicate that an artificial tellurium layer can be created in situ inside the battery and covered on metallic lithium, which can extend the battery's service life by 4 times.

Lithium-sulfur batteries have been hailed as the next generation of battery technology, promising to make products such as mobile phones and electric vehicles last longer, and they are more environmentally friendly than lithium-ion batteries. However, the disadvantage of this type of battery is that its service life is shorter than that of lithium-ion batteries and it will degrade over time. 

Lithium is a reactive element that breaks down other elements around it. Every charge and discharge cycle of a lithium-sulfur battery forms needle-shaped, moss-like deposits on the lithium metal anode (the battery's negative electrode), causing a reaction that degrades the battery as a whole. The deposits break down the electrolyte that transports lithium ions back and forth, leaving the electrode unable to provide enough energy to keep the battery going for longer, and the reaction can cause the battery to short-circuit, posing a fire hazard.

Solving the instability of lithium-sulfur batteries is the key to extending their service life and enabling their wider application.

The artificial tellurium layer formed on the lithium electrode protects the electrolyte from degradation and reduces the moss structure that forms during charging and traps lithium. The stabilizing layer is formed using a simple in-situ process, without the need for complex pretreatment or lithium metal anode coating processes.

Compared with current lithium-ion batteries, lithium-sulfur batteries have a nine-fold higher charge capacity for both positive and negative electrodes, and can be used for longer periods of time on a single charge. Due to the abundance of sulfur, the production cost of this type of battery is also very low. In addition, sulfur is more environmentally friendly than the metal oxide materials in lithium-ion batteries.

The researchers say the approach could also be applied to other lithium-based and sodium-based batteries, and have filed a provisional patent for the technology. Lithium-sulfur batteries are best suited for devices that require lightweight batteries that can run for long periods of time on a single charge without requiring multiple charging cycles. Lithium-sulfur batteries also have the potential to play an important role in extending the range of electric vehicles and increasing the adoption of renewable energy.