Patent attributes
To offer excellent hermeticity inside a battery having high productivity and being covered with package members by means of solving a problem such as sealing failures caused by gaps between sides of lead electrodes and the package members in sealing parts, in which the lead electrode to be disposed. During a step of sealing between ends of the package members and the lead electrodes by fusing the sealing members, or during a step of adhering the fused sealing members to the lead electrodes, stripping sheets made of a material such that the fused sealing members does not adhere to heaters, are inserted between the package members, or the sealing members and the heaters. Accordingly, even if the fused sealing members are forced out from ends of the package members, or leaked toward the outside, the sealing members does not adhere to surfaces of the heaters or crumble their shapes.