LITHIUM BATTERY AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: WATAGUCHI NOBUKI, TAKEUCHI YUKI, SHISHIHARA DAISUKE, HIKOSAKA HIDEAKI
• Format: Patent
• Language: English; Japanese
• Published: 29.11.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To suppress the initial performance and enduring performance of a lithium battery from worsening.SOLUTION: A lithium battery comprises a pair of electrode layers and a solid electrolyte layer. The solid electrolyte layer includes a first solid electrolytic material consisting of oxide having lithium ion conductivity as a primary component; and a second solid electrolytic material having lithium ion conductivity, of which the rate of an actual density to a theoretical density of a green compact subjected to an uniaxial pressurizing press with a predetermined pressure is 70% or more which is larger than that of the first solid electrolytic material. As to an index value indicative of a quantity of deformation in an axial direction when pressurization is disabled from the state of being pressurized with the predetermined pressure in a predetermined axial direction, an absolute value of the difference in index value between the first electrode layer and the solid electrolyte layer is larger than an absolute value of the difference in index value between the second electrode layer and the solid electrolyte layer. A contact area of the first electrode layer and solid electrolyte layer is smaller than that of the second electrode layer and solid electrolyte layer.SELECTED DRAWING: Figure 1 【課題】リチウム電池の初期性能や耐久性能が低下することを抑制する。【解決手段】リチウム電池は、２つの電極層と固体電解質層を備える。固体電解質層は、リチウムイオン伝導性を有する酸化物の第１の固体電解質材料を主成分として含み、リチウムイオン伝導性を有し、所定の圧力で一軸加圧プレスした圧粉体の理論密度に対する実密度の比が第１の固体電解質材料より大きく、かつ、７０％以上である第２の固体電解質材料を含む。所定の圧力で所定の軸方向に加圧した状態から加圧を解除したときの軸方向における変形量の大きさを表す指標値に関し、第１の電極層の指標値と固体電解質層の指標値との差の絶対値は、第２の電極層の指標値と固体電解質層の指標値との差の絶対値より大きい。第１の電極層と固体電解質層との接触面積は、第２の電極層と固体電解質層との接触面積より小さい。【選択図】図１