The modern world relies on portable electronic devices such as smartphones, tablets, laptops, cameras or camcorders. Many of these devices are powered by lithium-ion batteries, which could be smaller, lighter, safer and more efficient if the liquid electrolytes they contain were replaced by solids. A promising candidate for a solid-state electrolyte is a new class of materials based on lithium compounds, presented by physicists from Switzerland and Poland.
The modern world relies on portable electronic devices such as smartphones, tablets, laptops, cameras or camcorders. Many of these devices are powered by lithium-ion batteries, which could be smaller, lighter, safer and more efficient if the liquid electrolytes they contain were replaced by solids. A promising candidate for a solid-state electrolyte is a new class of materials based on lithium compounds, presented by physicists from Switzerland and Poland.
Commercially available lithium-ion batteries consist of two electrodes connected by a liquid electrolyte. This electrolyte makes it difficult for engineers to reduce the size and weight of the battery, in addition, it is subjected to leakage; the lithium in the exposed electrodes then comes into contact with oxygen in the air and undergoes self-ignition. Boeing's troubles, which for many months caused a full grounding of Dreamliner flights, are a spectacular example of the problems brought about by the use of modern lithium-ion batteries.
Laboratories have been searching for solid materials capable of replacing liquid electrolytes for years. The most popular candidates include compounds in which lithium ions are surrounded by sulphur or oxygen ions. However, in the journal Advanced Energy Materials, a Swiss-Polish team of scientists has presented a new class of ionic compounds where the charge carriers are lithium ions moving in an environment of amine (NH2) and tetrahydroborate (BH4) ions. The experimental part of the research project was carried out at Empa, the Swiss Federal Laboratories for Materials Science and Technology in Dübendorf, and at the University of Geneva (UG). The person responsible for the theoretical description of the mechanisms leading to the exceptionally high ionic conductivity of the new material was Prof. Zbigniew Lodziana from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow.
Continue reading at The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN)
Image: Lithium amide-borohydride is a promising candidate for a solid electrolyte. The crystalline structure of this material consists of two sub-lattices, shown in different colors. Under appropriate conditions, lithium ions (red), normally found in the elementary cells of only one sub-lattice (yellow), move to the empty cells of the second sub-lattice (blue) where they can freely propagate.
Credit: IFJ PAN
