In solid electrolytes, a Si anode made of commercial Si nanoparticles ready to expel deposition displays incredible electrode performance, new research led by NIMS scientists demonstrated.
The method mentioned is an affordable and atmospheric technique, and the performance exhibited has previously been noticed only for film electrodes developed by evaporation processes. This new outcome, therefore, implies that an affordable and extensive production of high-capacity anodes for the appliance in all-solid-state Li batteries is practicable.
Si has a hypothetical ability of ~4,200 mAh/g, which is about 11 times higher than that of the graphite typically used as the anode-active elements in commercial Li-ion batteries.
Substituting the usual graphite by Si can significantly increase the propulsion per charge of electric vehicles. Even so, its massive volume change, which is ~300 percent during lithiation and delithiation, commonly known as charge and discharge, obstructs its practical use in the batteries.
Further Research is Needed
In standard liquid electrolytes, the application of polymeric bonds is needed to hold the active material molecules in the electrode together and keep their bond to the surface of metal current collectors. The continual massive quantity change of Si makes the particle isolation and, therefore, conducts to losing the active material, which produces a continuous ability loss.
In solid-state cells, the active material is located between two solid elements, namely a solid electrolyte separator layer and metal current collector, which allows it to dodge the issue tackling, more precisely, the electrical isolation of the active material.
Further action taken by the team of NIMS scientists to enhance the cyclability in the anode while having the increased areal volume loading of nanoparticles is currently underway. These efforts will eventually meet the terms of electric vehicles.
Research explaining the Si anode made only of commercial nanoparticles in a sulfide solid electrolyte was published online on September 24th of this year, in the ACS Applied Energy Materials.