US Patent 7998614 Lithium ion rechargeable cell

A lithium ion rechargeable cell that is constructed by the steps of forming a cell unit (1) by packing an electrode group (10), in which plate-like positive and negative electrodes (12 and 14) and a plate-like separator (16) are superposed in layers, in a cell case (20) and sealing the electrode group together with an electrolyte; and forming a module by aligning and packing a plurality of cell units in a module case. The cell case is made of a laminated film (22). A porous spacer (30) made of insulating material is interposed in between the entire circumferential surface or partial surface of the electrode group and the laminated film.