Positive electrode and lithium battery utilizing the same

Abstract

Disclosed is a positive electrode applied in lithium battery and method for manufacturing the same. First, a lithium alloy oxide layer is formed on a substrate. Subsequently, an additional high density and low energy plasma treatment is processed, such that the lithium alloy oxide layer has a top surface composed of uniform, dense, and inter-necked nano grains, and the in-side/bottom grains of the oxide layer remain unchanged. According to experiments, the positive electrode with such properties has higher capacity and longer cycle lifetime, thereby improving the lithium battery performance.

1 . A positive electrode, comprising:
 a substrate consisting of stainless steel, polyamide, acrylonitrile-butadiene-styrene (ABS), mica, glass, poly(ethyleneterephthalate) (PET), poly-p-phenylene-benzobisoxazole (PBO), or epoxy resin; and   a lithium alloy oxide layer on the substrate;   wherein the lithium alloy oxide layer has uniform, dense, inter-necked nano grains on a top surface, and larger grains in a bottom structure.   
     
     
         2 . The positive electrode as claimed in  claim 1 , wherein the lithium alloy oxide layer comprises LiMnO 2 , LiMn 2 O 4 , LiCoO 2 , LiCr 2 O 7 , Li 2 CrO 4 , LiNiO 2 , LiFeO 2 , LiNi x Co 1-x O 2 , LiFePO 4 , LiMn 0.5 Ni 0.5 O 2 , LiMn 1/3 Co 1/3 Ni 1/3 O 2 , LiMc 0.5 Mn 1.5 O 4 , or combinations thereof, wherein 0<x<1 and Mc is divalent metal. 
     
     
         3 . A lithium battery, comprising:
 the positive electrode as claimed in  claim 1 ;   a negative electrode;   a separator film disposed between the positive electrode and the negative electrode to define a reservoir region;   a electrolyte solution in the reservoir region; and   a sealant structure wrapped around the positive electrode, the negative electrode, the separator film, and the electrolyte solution.