The electrolyte additive includes a neutral compound represented by formula (1) and having, in the molecule, a trialkyl silyl group. It can improve the withstand voltage of the electrolyte and be applied to electrolyte for lithium-ion rechargeable batteries. In formula (1), R.sup.1 each represent independent C1-8 alkyl groups, R.sup.2 each represent independent C1-8 alkyl groups, A represents a C1-10 alkylene group, X represents either a single bond, a methylene group or one of the linking groups represented by formulas (2) to (4), m represents an integer from 1 to 3, n represents an integer from 0 to 2, where m+n is 2 if X is a single bond, a methylene group, a linking group represented by formula (2) or a linking group represented by formula (3), and m+n is 3 if X is a linking group represented by formula (4). In formula (3), R.sup.3 represents a C1-8 alkyl group.

##STR00001##

A power storage module includes a laminate constituted of a plurality of laminated bipolar electrodes, each of the bipolar electrodes including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate, wherein a plurality of internal spaces is formed between the bipolar electrodes adjacent to each other in the laminate; a frame body holding an edge portion of the electrode plate and provided with an opening communicating with at least one of the plurality of internal spaces; and a pressure regulating valve attached to the frame body.

A power storage module includes a laminate constituted of a plurality of laminated bipolar electrodes, each of the bipolar electrodes including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate, wherein a plurality of internal spaces is formed between the bipolar electrodes adjacent to each other in the laminate; a frame body holding an edge portion of the electrode plate and provided with an opening communicating with at least one of the plurality of internal spaces; and a pressure regulating valve attached to the frame body.

Disclosed herein is a method of manufacturing a micro-supercapacitor with an increased storage capacity of electrical energy. The method is a method of manufacturing a high-capacity micro-supercapacitor including an anode and a cathode separated from each other, which includes forming a pair of current collectors by discharging conductive ink on a substrate surface with a 3D printer, and forming an electrode consisting of an anode and a cathode by stacking an electrode constituting material in the form of a plurality of layers on each of the pair of current collectors using the 3D printer.

An electricity storage device includes an internal element that has a first main surface, a second main surface, a first side surface, a second side surface, a first end surface, and a second end surface, and that further includes a first internal electrode drawn out to the first end surface, a second internal electrode drawn out to the second end surface, a separator layer disposed between the first and second internal electrodes, and an electrolytic solution. Moreover, a first end surface electrode is disposed on the first end surface; and a second end surface electrode is disposed on the second end surface. The first internal electrode, the second internal electrode, the separator layer, the first end surface electrode, and the second end surface electrode are integrally sintered to form a sintered body.

An electricity storage device includes an internal element that has a first main surface, a second main surface, a first side surface, a second side surface, a first end surface, and a second end surface, and that further includes a first internal electrode drawn out to the first end surface, a second internal electrode drawn out to the second end surface, a separator layer disposed between the first and second internal electrodes, and an electrolytic solution. Moreover, a first end surface electrode is disposed on the first end surface; and a second end surface electrode is disposed on the second end surface. The first internal electrode, the second internal electrode, the separator layer, the first end surface electrode, and the second end surface electrode are integrally sintered to form a sintered body.

A capacitor-assisted battery module includes a housing, a positive terminal, a negative terminal, one or more capacitor-assisted battery cells and one or more first switches. The one or more capacitor-assisted battery cells are disposed in the housing and include one or more battery terminals and one or more capacitor terminals. The one or more battery terminals are connected to battery electrodes. The one or more capacitor terminals are connected to capacitor electrodes. At least one of the one or more battery terminals and the capacitor terminals is connected to the negative terminal. One or more first switches is configured to connect the one or more capacitor terminals to the positive terminal. An overall voltage of the capacitor assisted battery module is measured across the positive terminal and the negative terminal.

A capacitor-assisted battery module includes a housing, a positive terminal, a negative terminal, one or more capacitor-assisted battery cells and one or more first switches. The one or more capacitor-assisted battery cells are disposed in the housing and include one or more battery terminals and one or more capacitor terminals. The one or more battery terminals are connected to battery electrodes. The one or more capacitor terminals are connected to capacitor electrodes. At least one of the one or more battery terminals and the capacitor terminals is connected to the negative terminal. One or more first switches is configured to connect the one or more capacitor terminals to the positive terminal. An overall voltage of the capacitor assisted battery module is measured across the positive terminal and the negative terminal.

An electric storage device includes a case having a substantially rectangular shape including a cutout part. An electrode body is disposed in the case and includes a first electrode, a second electrode, and a separator disposed between the first and second electrodes. An electrolyte is located in the case and at least partially impregnating the electrode body. A first electrode terminal is located on a first part of a side surface of the case and is electrically connected to the first electrode by a first connection member which has elasticity in a direction extending from the first electrode terminal to the first electrode. A second electrode terminal is located on a second part of the side surface of the case and is electrically connected to the second electrode by a second elastic connection member which has elasticity in a direction extending from the second electrode terminal to the second electrode.

An electric storage device includes a case having a substantially rectangular shape including a cutout part. An electrode body is disposed in the case and includes a first electrode, a second electrode, and a separator disposed between the first and second electrodes. An electrolyte is located in the case and at least partially impregnating the electrode body. A first electrode terminal is located on a first part of a side surface of the case and is electrically connected to the first electrode by a first connection member which has elasticity in a direction extending from the first electrode terminal to the first electrode. A second electrode terminal is located on a second part of the side surface of the case and is electrically connected to the second electrode by a second elastic connection member which has elasticity in a direction extending from the second electrode terminal to the second electrode.