TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Battery: The opposing positive and negative electrodes are preferably interleaved with the electrolyte layers, or separators as well. Total thickness of the electrolyte layer is 2-100 mum. The electrode mixture may also contain a binder to hold and maintain the electrolyte in even distribution throughout. Electrolyte of the electrode mixture can be made from an organic polymer, and such electrolyte is particularly obtained from a solution of an electrolyte salt in a plasticizer, which contains both high and low affinity structures.Preferred Process: The sheets of electrode-active material or its mixture with the electrolyte and monomer can be covered with a releasable film after forming into a desirable thickness to keep the electrolyte solution as a liquid film. During impregnation of the electrode-active sheet in the electrolyte solution, an ambient pressure or atmosphere at reduced pressure can be applied, particularly at 0.03-15 kPa, especially with further application of atmospheric pressure or pressurization afterwards e.g. at reduced pressure of 0.1-15 kPa and pressurization at not more than 400 kPa, in a sealable pressure-resistant vessel with sheet sealed at reduced pressure first and then the electrolyte is added. In step (a), the specified binder may also be added for mixing so that a binder-containing electrode can be obtained. A separator may also be inserted between the positive and negative electrodes.    TECHNOLOGY FOCUS - POLYMERS - Preferred Binder: Such binder can be polyvinylidene fluoride, hexafluoropropylene resin, or polyvinylidene and hexafluoropropylene copolymer. EXAMPLE - A positive electrode sheet was produced from lithium cobaltate as positive electrode-active material, acetylene black as conductor and polyvinylidene fluoride as binder in N-methyl-2-pyrrolidone by applying and pressing (0.1 mm thick) onto a current collector. The positive electrode sheet was soaked in a mixture of gamma-butyrolactone as plasticizer, 1 M LiBF4 and an organic monomer (see structure below) for 15 mins., covered with a peelable film and then irradiated with electron beam to effect polymerization. After removing the peelable film, a positive electrode was obtained with a 10-mum thick electrolyte layer. Similarly, a negative electrode was produced with carbon as negative electrode-active material and copper foil as negative electrode current collector. A battery was then assembled. Capacitance of the battery (total electrolyte layer thickness being 20 mum) was 10 mAh, with no occurrence of internal short circuits. Structure of Monomer.    CH2=CH-CO-O-(CH2CH2)2-X-C(CH3)2X-(OCH2CH2)2-O-CO-CH=CH2    (X = p-phenylene)