the mandrel 11 the wound assembly was inserted into a can electrolyte injection assembling and formation were performed to fabricate a cell as shown in fig1 a cathode 13 having a size of 114 u00d7 35 u00d7 0 73 mm and an anode 15 having a size of 149 u00d7 35 u00d7 0 40 mm were arranged on opposing sides of separator 17 having a size of 263 u00d7 38 u00d7 0 15 mm after winding the cathode 13 the anode 15 and the separator 17 around the mandrel 11 the wound assembly was inserted into a can electrolyte injection assembling and formation were performed to fabricate a cell as shown in fig2 a cathode 13 having a size of 114 u00d7 35 u00d7 0 73 mm and an anode 15 having a size of 149 u00d7 35 u00d7 0 73 mm were arranged on opposing sides of a separator 17 having a size of 263 u00d7 38 u00d7 0 15 mm an additional separator 31 having a size of 149 u00d7 35 u00d7 0 15 mm enough to cover the initial parts of the cathode 13 and the anode 15 was placed on the cathode side of the separator 17 after winding the cathode 13 the anode 15 the separator 17 and the additional separator 31 around the mandrel 11 the wound assembly was inserted into a can electrolyte injection assembling and formation were performed to fabricate a cell the following table shows the results of measuring the volume of a cell injection volume of an electrolyte internal pressure and durability according to the above examples and comparative examples table______________________________________ injection internal volume of an pressure durabilityvolume mm sup 3 electrolyte g kg cm sup 2 cycle ______________________________________example 1 1647 3 3 10 250comparative 1500 3 3 10.