Abstract: A cell such as a lithium ion cell consists of an anode and a cathode comprising respective lithium ion insertion materials, separated by an electrolyte. A practical cell may be made by stacking a plurality of anode plates (14) and cathode plates (12) alternately, and interleaving a continuous layer (10) of polymer electrolyte or separator material between successive anode and cathode plates so it forms a zigzag. If the continuous layer is a separator, the assembly is then contacted with a solution comprising lithium salt in a compatible organic solvent, which provides the cell electrolyte. This procedure enables cells to be made with thin electrolyte layers, for example less than 30 ?m thick, and hence of low internal resistance.

Abstract: A cell such as a lithium ion cell consists of an anode and a cathode comprising respective lithium ion insertion materials, separated by an electrolyte. A practical cell may be made by stacking a plurality of anode plates (14) and cathode plates (12) alternately, and interleaving a continuous layer (10) of polymer electrolyte or separator material between successive anode and cathode plates so it forms a zigzag. If the continuous layer is a separator, the assembly is then contacted with a solution comprising lithium salt in a compatible organic solvent, which provides the cell electrolyte. This procedure enables cells to be made with thin electrolyte layers, for example less than 30 &mgr;m thick, and hence of low internal resistance.