Performance Improvement of the All-Solid-State Battery Using Porous Li_(0.33)La_(0.56)TiO_3 Membrane By Sol-Gel Method

摘要

The all-solid-state battery using a solid electrolyte has no risk of liquid leakage or ignition and it is highly reliable in terms of safety. Unlike conventional organic electrolytes, they have no fluidity, so they can be stacked. Furthermore, solid electrolytes show single conduction in which only Li~+ ions move in the electrolyte. Therefore, it is expected that a high energy density can be obtained, and it is expected to be load in an electric vehicle as a next-generation storage battery. However, in all-solid-state battery, since each material is solid, it is not possible to form an interface as easily as a solid-liquid interface. In other words, the biggest challenge of all-solid-state batteries is the reducing of electrode/electrolyte interface resistance. In our laboratory, it was found that LiCoO_2 (LCO) formed on a LLTO substrate using a molten salt of Li and Co has a low interface resistance (about 40 Ω cm~2) and high electrochemical activity. However, the film thickness obtained by this method is as thin as 1 μm. It is the active material that stores energy, and even if it is a thin film, it cannot move an electric vehicle. Thus, the purpose of this paper is to increase the amount of active material by using a porous LLTO membrane to three-dimensionally fill the LLTO with molten salt LCO.