TECHNOLOGY FOCUS - METALLURGY - Preferred Components: The negative electrode contains a metallic element, a semi-metal element as a constituent element and a carbon material, preferably silicon, and tin (Sn), cobalt (Co) and carbon (C). Preferred Properties: The ratio of (Co/(Sn+Co)) is 9.9 to 29.7 mass%. The half value width of diffraction peak obtained by X-ray diffraction of SnCoC containing material is greater than or equal to 1 degree and the carbonaceous content is 20-70 mass%. The negative electrode occludes and discharges a lithium ion as a negative electrode active material and lithium metal.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The cyclic polyester is of formula (I), preferably 1,3,7,9-tetraoxa-cyclododecane-4,6,10,12-tetraone, 5,5,11,11-tetrafluoro-1,3,7,9-tetraoxa-cyclododecane-4,6,10,12-tetraone, 2,2,5,5,8,8,11,11-octafluoro-1,3,7,9-tetraoxa-cyclododecane-4,6,10,12-tetraone, 1,4,8,11-tetraoxa-cyclotetradecane-5,7,12,14-tetraone, 2,2,3,3,9,9,10,10-octafluoro-1,4,8,11-tetraoxa-cyclotetradecane-5,7,12,14-tetraone, 2,2,3,3,6,6,9,9,10,10,13,13-dodecafluoro-1,4,8,11tetraoxa-cyclotetradecane-5,7,12,14-tetraone, 6,6,13,13-tetrafluoro-1,4,8,11-tetraoxa-cyclotetradecane-5,7,12,14-tetraone, 1,5,9,13-tetraoxa-cyclohexadecane-2,4,10,12-tetraone, 3,3,11,11-tetrafluoro-1,5,9,13-tetraoxa-cyclohexadecane-2,4,10,12-tetraone, 6,6,7,7,8,8,14,14,15,15,16,16-dodecafluoro-1,5,9,13-tetraoxa-cyclohexadecane-2,4,10,12-tetraone, 3,3,6,6,7,7,8,8,11,11,14,14,15,15,16,16-hexadecafluoro-1,5,9,13tetraoxa-cyclohexadecane-2,4,10,12-tetraone, 3,3,6,6,7,7,8,8,11,11,14,14,15,15,16,16-hexadecafluoro-1,5,9,13-tetraoxa-cyclohexadecane-2,4,10,12-tetraone, 1,3,5,7,11,13,15,17-octaoxa-cycloicosane-8,10,18,20-tetraone, 1,4,7,11,14,17-hexaoxa-cycloicosane-8,10,18,20-tetraone, 1,4,7,10,14,17,20,23-octaoxa-cyclohexacosane-11,13,24,26-tetraone, 9,9,19,19-tetrafluoro-1,4,7,11,14,17-hexaoxa-cycloicosane-8,10,18,20-tetraone, (1,3,7)-trioxecane-4,6,8,10-tetraone, 1,4,8-trioxa-cycloundecane-5,7,9,11-tetraone, 1,5,9-trioxa-cyclododecane-2,4,6,8-tetraone, 1,4,9,12-tetraoxa-cyclohexadecane-5,8,13,16-tetraone, (2Z,6Z,10Z,14Z)-1,4,9,12-tetraoxa-cyclohexadeca-2,6,10,14-tetraene-5,8,13,16-tetraone, 1,4,9,12-tetraoxa-cyclohexadeca-2,6,10,14-tetrayne-5,8,13,16-tetraone, and tetraone compounds of formulae (II and III).R1-R4=divalent organic group;m,n=0-3;andm+n=greater than or equal to 1.Preferred Property: The content of cyclic polyester is 0.01-10 weight%.