Lithium ionic energy storage element and method for making the same

Abstract

A lithium ionic energy storage element comprises a positive electrode having a first current collector and a positive electrode active substance provided on the first current collector; a negative electrode having a second current collector and a negative electrode active substance provided on the second current collector, wherein the negative electrode active substance is a material selected from the group consisting of carbon-containing materials, Si alloy and Sn alloy; and an electrolyte, wherein the positive electrode active substance comprises a lithium ion donor including lithium peroxide, lithium oxide or the mixture thereof and a positive electrode frame active substance. The invention also relates to a method for making a lithium ionic energy storage element.

What is claimed is: 
     
         1 . A positive electrode active substance used in a lithium ionic energy storage element, the positive electrode active substance comprising a lithium ion donor and a positive electrode frame active substance, wherein the lithium ion donor includes lithium peroxide, lithium oxide or a combination of lithium peroxide and lithium oxide; and the positive electrode frame active substance is a material selected from the group consisting of anatase titanium dioxide, carbon-sulfur composite, carbon-containing materials, carbon fluoride and—is lithium metallic oxides. 
     
     
         2 . A lithium ionic energy storage element comprising:
 a positive electrode having a first current collector and a positive electrode active substance provided on the first current collector;   a negative electrode having a second current collector and a negative electrode active substance provided on the second current collector, wherein the negative electrode active substance is a material selected from the group consisting of carbon-containing materials, Si alloy and Sn alloy; and   an electrolyte interposed between the positive electrode and the negative electrode, wherein the positive electrode active substance comprises a lithium ion donor including lithium peroxide, lithium oxide or a combination of lithium peroxide and lithium oxide and a positive electrode frame active substance.   
     
     
         3 . The lithium ionic energy storage element as claimed in  claim 2 , wherein the positive electrode frame active substance of the positive electrode active substance is a material selected from the group consisting of anatase titanium dioxide, carbon-sulfur composite, carbon-containing materials, carbon fluoride and lithium metallic oxides. 
     
     
         4 . The lithium ionic energy storage element as claimed in  claim 3 , wherein the carbon-sulfur composite of the positive electrode frame active substance has a weight ratio of carbon with sulfur is 0.4-1. 
     
     
         5 . The lithium ionic energy storage element as claimed in  claim 2 , wherein the positive electrode frame active substance is lithium metallic oxides. 
     
     
         6 . The lithium ionic energy storage element as claimed in  claim 2 , wherein the positive electrode active substance contains conductive carbon comprising super P carbon black, KS6 graphite or a combination thereof. 
     
     
         7 . A method for making a lithium ionic energy storage element comprising steps:
 (a) mixing a lithium ion donor, a positive electrode frame active substance and a binder with a predetermined weight ratio to form a mixture, and adding the mixture into a dispersant to form a positive electrode active substance, wherein the lithium ion donor includes lithium peroxide, lithium oxide or a combination thereof;   (b) coating the positive electrode active substance on an aluminum foil to form a film, and baking the film to form a positive electrode; and   (c) forming a lithium ionic energy storage element by assembling the positive electrode, a negative electrode having a negative electrode active substance and a porous separate strip interposed between the positive electrode and the negative electrode, and filling an electrolyte into the porous separate strip.   
     
     
         8 . The method as claimed in  claim 7 , further comprising an oxygen removal step for removing oxygen produced in a first cycle of charge and discharge the lithium ionic energy storage element after filling the electrolyte into the porous separate strip. 
     
     
         9 . The method as claimed in  claim 7 , wherein the positive electrode frame active substance of the step (a) is a material selected from the group consisting of anatase titanium dioxide, carbon-sulfur composite, carbon-containing materials and carbon fluoride. 
     
     
         10 . The method as claimed in  claim 7 , wherein the positive electrode frame active substance of the step (a) is lithium metallic oxides. 
     
     
         11 . The method as claimed in  claim 7 , further comprising adding a conductive carbon into the mixture of the step (a), wherein the conductive carbon is super P carbon black, KS6 graphite or a combination thereof. 
     
     
         12 . The method as claimed in  claim 7 , wherein the binder in the step (a) is polyvinylidene fluoride or carboxymethyl cellulose. 
     
     
         13 . The method as claimed in  claim 7 , wherein the negative electrode active substance of the step (c) is a material selected from the group consisting of graphitized mesocarbon microbeads, hard carbon, Si alloy and Sn alloy. 
     
     
         14 . The method as claimed in  claim 7 , wherein the electrolyte of the step (c) is a concentration of 1M LiPF 6 dissolving in a mixing solution of ethylene carbonate and diethyl carbonate; or a concentration of 1M lithium bis(trifluoromethanesulfonly)imide dissolving in a mixing solution of tetraethylene glycol dimethyl ether and 1,3-dioxolane. 
     
     
         15 . The method as claimed in  claim 7 , wherein the dispersant of the step (a) is N-methyl-2-pyrrolidone.