Electrode for lithium secondary battery, method of manufacturing the same, and lithium secondary battery including the same

Abstract

An electrode for a lithium secondary battery, the electrode including: an electrode active material; and a composite including a clay and a polymer intercalated between layers of the clay, a method of manufacturing the electrode, and a lithium secondary battery including the electrode.

1 . An electrode for a lithium secondary battery, the electrode comprising:
 an electrode active material; and   a composite comprising a clay and a polymer intercalated between layers of the clay.   
     
     
         2 . The electrode of  claim 1 , wherein the clay comprises at least one selected from the group consisting of montmorillonite, bentonite, saponite, beidellite, nontronite, hectorite, and stevensite. 
     
     
         3 . The electrode of  claim 1 , wherein the polymer comprises at least one selected from the group consisting of polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), and polyacrylic acid (PAA). 
     
     
         4 . The electrode of  claim 1 , wherein an amount of the composite is from about 0.1 to about 20 parts by weight based on 100 parts by weight of the electrode active material. 
     
     
         5 . The electrode of  claim 1 , wherein the electrode active material comprises at least one selected from the group consisting of lithium iron phosphate (LiFePO 4 ), lithium cobalt oxide (LiCoO 2 ), lithium manganese oxide (LiMnO 2 ), lithium nickel oxide (LiNiO 2 ), and lithium nickel cobalt manganese oxide (LiNiCoMnO 2 ). 
     
     
         6 . The electrode of  claim 1 , further comprising a conducting agent. 
     
     
         7 . The electrode of  claim 6 , wherein the conducting agent comprises a carbonaceous material. 
     
     
         8 . The electrode of  claim 6 , wherein the amount of the conducting agent is from about 1 to about 10 parts by weight based on 100 parts by weight of the electrode active material. 
     
     
         9 . The electrode of  claim 1 , wherein the electrode is a positive electrode. 
     
     
         10 . A lithium secondary battery comprising an electrode comprising:
 an electrode active material; and   a composite comprising a clay and a polymer intercalated between layers of the clay.   
     
     
         11 . The lithium secondary battery of  claim 10 , wherein the polymer comprises at least one selected from the group consisting of polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), and polyacrylic acid (PAA). 
     
     
         12 . The lithium secondary battery of  claim 10 , wherein an amount of the composite is from about 0.1 to about 20 parts by weight based on 100 parts by weight of the electrode active material. 
     
     
         13 . A method of manufacturing an electrode for a lithium secondary battery, the method comprising:
 preparing a clay dispersion by dispersing clay in a first solvent;   preparing a composite by mixing the clay dispersion with a polymer or a polymer solution prepared by dissolving the polymer in a second solvent:   preparing a composition for forming an electrode active material layer by adding an electrode active material to the composite and mixing the electrode active material and the composite; and   coating and drying the composition on a current collector to form an electrode active material layer.   
     
     
         14 . The method of  claim 13 , wherein the amount of the polymer is from about 5 to about 2000 parts by weight based on 100 parts by weight of the clay. 
     
     
         15 . The method of  claim 13 , wherein a conducting agent is further used in preparing the composition. 
     
     
         16 . A method of manufacturing an electrode for a lithium secondary battery, the method comprising:
 melting clay and a polymer by using a heat treatment;   extruding the molten product to form a composite;   preparing a composition for forming an electrode active material layer by dissolving the composite in a third solvent, adding an electrode active material thereto, and mixing the resultant mixture; and   coating and drying the composition on a current collector to form an electrode active material layer.   
     
     
         17 . The method of  claim 16 , wherein the amount of the polymer is from about 5 to about 2000 parts by weight based on 100 parts by weight of the clay. 
     
     
         18 . The method of  claim 16 , wherein a conducting agent is further used in preparing the composition. 
     
     
         19 . A lithium secondary battery comprising an electrode manufactured by the method of  claim 13 . 
     
     
         20 . A lithium secondary battery comprising an electrode manufactured by using the method of  claim 16 .