Scientists from Washington State University have done an important work in the development of lithium-ion batteries. Researchers have created a more efficient battery technology by replacing the anode and electrolyte combinations in lithium-ion batteries.
Scientists continue to work to develop lithium-ion batteries used in mobile devices and electric vehicles. One of the areas in which battery technology is studied is the development of anode and cathode compositions of lithium-ion batteries.
Lithium-ion batteries discharge after charging, while electrons alternate between anode and cathode. The batteries used today are made of anode, graphite and copper. Scientists from Washington State University (WSU) have tried to use pure lithium metal instead of this graphite, copper composition found in the anode.
Kyu Song, one of the researchers, explained that pure lithium metal can offer much higher energy density than copper-graphite composition and will last twice as long. “If we can use lithium metal directly, we can significantly increase the energy density of the batteries,” said Song.
However, efforts of scientists from WSU to use pure lithium metal in the anode section have faced safety issues. Lithium ions fluctuated between the cathode and the anode formed from lithium metal, causing protrusions on the surface of the material. These protrusions in lithium cause short circuit and then fire. The overhangs caused the battery to discharge quickly if they did not cause a fire.
After the problem that appeared on the surface of lithium, scientists started working on alternatives to solve this problem. As a solution, after forming the cathode part from a porous carbon structure, a chemical named selenium disulfide was placed in it. Several additives were added to the electrolyte solution, which ensures the movement of lithium ions between the cathode and anode.
This mixture caused the anode surface consisting of lithium metal to form a self-protective layer. This protective layer prevented the protrusions formed on the surface of the lithium metal. The team was able to charge the battery created in this way 500 times during the test.
Scientists working in the field of battery technology development are trying to use solid electrolytes as another way. Studies on these batteries, known as solid-state batteries, at MIT and the Deakin University of Australia revealed important examples. However, the experiment of using lithium instead of anode at WSU seems to be more efficient than solid state batteries at this stage.