Non-aqueous electrolyte secondary battery

Abstract

According to one embodiment, there is provided a non-aqueous electrolyte secondary battery including a positive electrode including a positive electrode active material layer, a negative electrode including a negative electrode active material layer, and a non-aqueous electrolyte. At least one of the positive electrode active material layer and the negative electrode active material layer contains carbon dioxide and releases the carbon dioxide in the range of 0.1 ml to 10 ml per 1 g when heated at 350° C. for 1 minute.

What is claimed is: 
     
         1 . A non-aqueous electrolyte secondary battery comprising:
 a positive electrode comprising a positive electrode active material layer;   a negative electrode comprising a negative electrode active material layer; and   a non-aqueous electrolyte;   wherein at least one of the positive electrode active material layer and the negative electrode active material layer contains carbon dioxide and releases the carbon dioxide in the range of 0.1 ml to 10 ml per 1 g when heated at 350° C. for 1 minute.   
     
     
         2 . The battery according to  claim 1 , wherein at least one of the positive electrode active material layer and the negative electrode active material layer shows two peaks appearing in the range of 120° C. to 350° C. in the pyrolysis-gas chromatography/mass spectrometry under a temperature rising condition of 5° C./minute, and an inequality  a ≦ b  is satisfied where  a  is a peak intensity of the low-temperature side of the two peaks and  b  is a peak intensity of the high-temperature side of the two peaks. 
     
     
         3 . The battery according to  claim 2 , wherein the negative electrode active material layer comprises lithium titanium composite oxide, and
 the negative electrode active material layer shows two peaks appearing in the range of 120° C. to 350° C. in the pyrolysis-gas chromatography/mass spectrometry under a temperature rising condition of 5° C./minute, and the peak of the low-temperature side of the two peaks appears in the range of 120° C. or more and less than 200° C. and the peak of the high-temperature side appears in the range of 200° C. to 350° C.   
     
     
         4 . The battery according to  claim 3 , wherein the negative electrode active material layer releases carbon dioxide in the range of 0.1 ml to 5 ml per 1 g when heated at 350° C. for 1 minute. 
     
     
         5 . The battery according to  claim 2 , wherein the positive electrode active material layer comprises at least an oxide selected from the group consisting of lithium manganese composite oxide, lithium nickel composite oxide and lithium composite phosphate compound, and the positive electrode active material layer shows two peaks appearing in the range of 120° C. to 350° C. in the pyrolysis-gas chromatography/mass spectrometry under a temperature rising condition of 5° C./minute, and the peak of the low-temperature side of the two peaks appears in the range of 120° C. or more and less than 250° C. and the peak of the high-temperature side appears in the range of 250° C. to 350° C. 
     
     
         6 . The battery according to  claim 5 , wherein the positive electrode active material layer releases carbon dioxide in the range of 0.5 ml to 10 ml per 1 g when heated at 350° C. for 1 minute. 
     
     
         7 . The battery according to  claim 2 , wherein
 the negative electrode active material layer comprises lithium titanium composite oxide;   the negative electrode active material layer shows two peaks appearing in the range of 120° C. to 350° C. in the pyrolysis-gas chromatography/mass spectrometry under a temperature rising condition of 5° C./minute, and the peak of the low-temperature side of the two peaks appears in the range of 120° C. or more and less than 200° C. and the peak of the high-temperature side appears in the range of 200° C. to 350° C.;   the positive electrode active material layer comprises at least an oxide selected from the group consisting of lithium manganese composite oxide, lithium nickel composite oxide and lithium composite phosphate compound; and   the positive electrode active material layer shows two peaks appearing in the range of 120° C. to 350° C. in the pyrolysis-gas chromatography/mass spectrometry under a temperature rising condition of 5° C./minute, and the peak of the low-temperature side of the two peaks appears in the range of 120° C. or more and less than 250° C. and the peak of the high-temperature side appears in the range of 250° C. to 350° C.