▎ 摘　　要

NOVELTY - A positive electrode for a lithium battery has: a composite material comprising a positive active material as a core of the composite material, and a coating layer located on a surface of the positive active material forming a shell on the core of the composite material. The coating layer comprises a copolymer comprising an aryl first repeating unit (1), and a second repeating unit (2). USE - Positive electrode for a lithium battery such as all solid battery (claimed). ADVANTAGE - The lithium battery including a solid electrolyte stores a large amount of electrical energy, has improved stability, and a decreased risk of explosion by ignition, as compared to a lithium battery including a liquid electrolyte. The solid electrolyte includes a sulfide-based electrolyte having excellent ionic conductivity and applicable to fast charging/discharging environments. The composite positive active material has excellent stability at a high voltage, excellent mechanical properties, and increased elasticity capable of preventing deformation of the coating layer even in a volume changing environment. The composite positive active material is able to effectively inhibit side reactions between the sulfide-based solid electrolyte and the positive electrode. By using the copolymer as a material for forming a coating layer on the positive active material, an oxidation reaction between the solid electrolyte and the positive active material is suppressed due to minimal contact between the sulfide-based solid electrolyte and the positive active material. Due to the decreased number of interfacial side reactions, a passage for effectively transferring lithium ions is provided, and the positive active material is not broken or damaged by volume changes thereof. Thus, a lithium battery having excellent cycle characteristics and high energy density may be manufactured. The effect of inhibiting an interfacial side reaction between the positive electrode and the solid electrolyte is improved, thus improving stability at a high voltage. The positive electrode including the composite positive active material has electrochemical stability at a high voltage, lithium ion-delivering capability, and mechanical properties which resist volume changes. Thus, the cycle characteristics of the lithium battery including the positive electrode may be improved by having a high capacity retention ratio under charge/discharge conditions and stably maintaining the interface between the positive electrode and the solid electrolyte under long-term charging/discharging cycle environments. DETAILED DESCRIPTION - A positive electrode for a lithium battery has: a composite material comprising a positive active material as a core of the composite material, and a coating layer located on a surface of the positive active material forming a shell on the core of the composite material. The coating layer comprises a copolymer comprising an aryl first repeating unit of formula (1), and a second repeating unit of formula (2). (Ar1= 6-30C-(hetero)arylene group (optionally substituted); R1-R3= 1-30C-alkyl, 6-30Caryl, or 3-30C-heteroaryl (all optionally substituted), or H; A = 1-30C-alkylene, 6-30C-arylene, 3-30C-heteroarylene, 4-30C-cycloalkylene, or 3-30C-heterocycloalkylene (all optionally substituted), or a bond; Ring X' = 3- 31-membered ring system comprising 2-30C; = X = -S, -N(R), or -P(R'); R, R' = 1-30C-alkyl, 1-30C-heteroalkyl, 1-30C-alkoxy, 6-30C-aryl, 7-30C-arylalkyl, 6-30C-aryloxy, 3-30C-heteroaryl, 4-30C-heteroarylalkyl, 3-30C-cycloalkyl, 2-30C-alkenyl, or 3-30C-alkynyl (all optionally substituted) or H; Y-= anion; A1= -C(=O)O-CH2CH2O)a-R7; R7= 1-30C-alkyl, or 6-30C-aryl (both optionally substituted), or H; a = 1-10; R4-R6= 1-30C-alkyl, 6-30C-aryl, or 3-30C-heteroaryl (all optionally substituted) or H; and m, n = 0-1; or m+n = 1) An INDEPENDENT CLAIM is included for a lithium battery, which comprises the positive , a negative electrode, and a solid electrolyte interposed between the positive electrode and the negative electrode and comprising a sulfide solid electrolyte and/or an oxide solid electrolyte.