Abstract: A purpose of the present invention is to provide an electrode assembly and a manufacturing method therefor that can favorably suppress a short circuit that is due to a burr created by punching. At least one of the cathode 11 and the anode 12 of the electrode assembly of the present invention is covered with an insulating layer. The cathode 11 and the anode 12 are oriented such that the burr 11b of the cathode 11 and the burr 12b of the anode 12 of the opposing cathode 11 and the opposing anode 12 close to at least the outer peripheral edge of the cathode 11 and the outer peripheral edge of the anode 12 do not face each other 12 are opposed to each other.

Abstract: An electrospun coated component for a lead acid battery is disclosed. The electrospun coated component includes positive electrode, negative electrode, and separator. The separator may comprise a low-conducting and/or non-conductive material. A method of electrospun coating these components of a LAB is provided. Suitable compositions and conditions for electrospun coating on to LAB components are further provided in this disclosure.

Abstract: The present invention relates to an electrode assembly and a method for manufacturing the same, and more particularly, to an electrode assembly in which a degree of alignment of cells is improved and a method for manufacturing the same. An electrode assembly according to the present invention comprises a separator sheet folded in a zigzag shape and a unit cell having a structure in which an electrode and a separator are alternately stacked, wherein the unit cell is repeatedly disposed between the separator sheet that is folded in a zigzag shape, and at least a portion of the unit cell and at least a portion of the separator sheet are bonded to each other.

Abstract: A first separator (130) covers a first surface of a cathode electrode (110). The first separator (130) has a melting point of a first temperature. A second separator (140) covers a second surface of the cathode electrode (110). The second separator (140) has a melting point of a second temperature higher than the first temperature. An adhesive layer (132) is formed by melting a portion of the first separator (130). The adhesive layer (132) pastes the first separator (130) and the second separator (140) to each other.

Abstract: The present invention relates to an electrode assembly including at least two electrode plates and a separator interposed between the electrode plates, wherein indented portions are formed from lower ends of opposite sides of the electrode tab in an opposite direction to an externally extending direction of the electrode tab in a side of the electrode body in which the electrode tab externally extends, in the electrode plates.

Abstract: The present invention provides a unit cell for a nickel-zinc battery in the form of a cell pack having positive and negative electrodes reliably separated by a hydroxide ion-conductive separator, which can be readily handled and is very advantageous for forming an assembled battery. The nickel-zinc cell pack of the invention includes: a flexible bag comprising flexible films; a separation sheet liquid-tightly connected to the interior of the flexible bag to separate a positive-electrode chamber and a negative-electrode chamber for inhibiting liquid communication therebetween; a positive electrode and a positive-electrode electrolytic solution disposed in the positive-electrode chamber; a negative electrode and a negative-electrode electrolytic solution disposed in the negative-electrode chamber, wherein the separation sheet comprises a separator structure comprising a separator exhibiting hydroxide-ion conductivity and water impermeability.

Abstract: An electrode laminate is located in a case. The electrode laminate has opposed first and second principal surfaces and opposed first and second lateral side surfaces. The electrode laminate includes a positive electrode having a planar main surface and first and second opposed lateral ends located on opposite lateral sides of its main surface, a negative electrode having a planar main surface and first and second opposed lateral ends located on opposite lateral sides of its main surface, the main surface of the positive electrode opposing the main surface of the negative electrode. A separator is located between the opposed main surfaces of the positive and negative electrodes and has first and second lateral ends extending laterally outward from the first and second lateral ends of the positive and negative electrodes, respectively. At least a tip of the first and second lateral ends of the separator are bent in a direction towards the first principal surface of the electrode laminate.

Abstract: A battery includes at least an electrode group including a positive electrode, a separator, a negative electrode, and a protection layer. The separator is interposed between the positive electrode and the negative electrode. The positive electrode includes a positive electrode current collector, a positive electrode mixture layer, and a positive electrode tab. The positive electrode mixture layer is disposed on a surface of the positive electrode current collector. The positive electrode tab is electrically connected to the positive electrode current collector. The protection layer covers a surface of the positive electrode tab. A volume resistivity of the protection layer is within a range of one to 100 times a volume resistivity of the positive electrode mixture layer.

Abstract: In the case where a film, which has lower strength than a metal can, is used as an exterior body of a secondary battery, a current collector provided in a region surrounded by the exterior body, an active material layer provided on a surface of the current collector, or the like might be damaged when force is externally applied to the secondary battery. A secondary battery that is durable even when force is externally applied thereto is provided. A cushioning material is provided in a region surrounded by an exterior body of a secondary battery. Specifically, a cushioning material is provided on the periphery of a current collector such that a sealing portion of an exterior body (film) is located outside the cushioning material.

Abstract: A rechargeable battery includes positive and negative electrodes and first and second separator portions. The positive electrode includes a positive metal foil and a positive active material layer. A positive active material-free portion is formed on a first end of the positive electrode. The positive active material layer extends to a second end. The negative electrode includes a negative metal foil and a negative active material layer. A negative active material-free portion is formed on a third end of the negative electrode. The negative active material layer extends to a fourth end. Each of the first and second separator portions includes a strong bonding portion and a weak bonding portion. The strong bonding portion is located proximate to the first end and extends along the first end. The weak bonding portion is located proximate to the second end and extends along the second end.

Abstract: The present disclosure provides a method of casting ribs on substrate, said method comprising acts of, mounting applicator comprising plurality of nozzles and polymer filled into the applicator, placing the substrate below the nozzles of the applicator, applying pressure onto the melt polymer to cast plurality of polymer ribs of predetermined shape on the substrate, and cooling the substrate casted with ribs.

Abstract: According to one embodiment, an electrode structure is provided. The electrode structure includes a current collector, a separator layer, and an active material layer including a main surface and a first end face other than the main surface. The active material layer covers a first part of at least one surface of the current collector. The separator layer covers the main surface of the active material layer, at least a part of the first end face and second part of the at least one surface of the current collector.

Abstract: A battery separator for a lead acid (storage) battery is made from a thermoplastic sheet material. The sheet material has a central region flanked by peripheral regions. The central region includes a plurality of longitudinally extending ribs that are integrally formed from the sheet material. The peripheral regions are free of ribs and may include a densified structure. Also disclosed are a method of producing the foregoing separator, an envelope separator made from the sheet material, and a method of making the envelope separator.

Abstract: A stacked battery including two kinds of electrodes 1, 2 and separators 3 through each of which one of the two kinds of electrodes 1 is stacked on another of the two kinds of electrodes 2, each of separators 3 including bonding portion 7 in which separator 3 stacked on the one of the two kinds of electrodes 1 and separator 3 stacked on the another of the two kinds of electrodes 2 are partly bonded to each other on a lateral side of the one of the two kinds of electrodes 1, and non-bonding portion 8 in a curve form which extends at least from a position in which separator 3 is contacted with an end surface of the another of the two kinds of electrodes 2 toward a lateral side of the another of the two kinds of electrodes 2.

Abstract: Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate. Representative ceramic selective membranes include ion-conductive membranes (e.g., proton-conducting membranes) and gas selective membranes. Representative uses for the membranes include incorporation into fuel cells and redox flow batteries (RFB) as ion-conducting membranes.

Abstract: This electricity storage device comprises an electrode assembly, a case, an electrode terminal and a conductive member. The electrode assembly comprises a positive electrode, a negative electrode and a separator. The separator comprises a first separator part and a second separator part. The separator has a container part that contains portions of the positive electrode other than a tab. The separator has a welded part and a tab facing part. The welded part has facing parts that are positioned on both sides of the tab facing part. The facing parts face the electrode terminal with the conductive member being interposed therebetween. The facing parts are larger in shrinkage amount associated with thermal welding than the other portions of the welded part.

Abstract: A cell in which thermal welding of a laminate packaging is performed so that the thickness of a thermal welded portion including an electrode terminal is larger than that of a thermal welded portion including no electrode terminal.

Abstract: Binder for an electrode of an electrochemical system having a non-aqueous electrolyte, said binder comprising a first polymer which has functional groups capable of reacting with a crosslinking agent and is crosslinked with said crosslinking agent, the crosslinked first polymer forming a three-dimensional network in which a second polymer chosen from fluoropolymers is imprisoned.

Abstract: A pouch battery including an electrode assembly, and a pouch case comprising a receiving part accommodating the electrode assembly, wherein corners or vertices of the receiving part are coated with a UV curing agent.

Abstract: An optical sensor (10) comprises an optical cavity defined by a dielectric body and responsive to one or more physical environmental conditions, and a waveguide (70) having a terminal end spaced apart from the optical cavity such that light is optically coupled from the terminal end of the waveguide (70) to the optical cavity. The waveguide (70) is arranged such that, in use, it is maintained at a first temperature that would not damage the optical coupling to the optical cavity when the dielectric body is maintained at a second temperature sufficient to damage the optical coupling to the optical cavity.

Abstract: To provide a power storage unit having a structure which is unlikely to break down by change in shape, such as bending. An electrode plate is covered with a sheet of an insulator which is folded in two. The sheet is preferably processed into a bag-like shape or an envelope-like shape by bonding overlapping portions of the sheet in the periphery of the electrode plate. The electrode plate and the sheet are fixed to an exterior body. In the case where the shape of the exterior body is changed by bending or the like, the electrode plate and the sheet can slide together in the exterior body. Thus, stress on the electrode plate due to bending can be relieved.

Abstract: A rechargeable battery includes positive and negative electrodes and first and second separator portions. The positive electrode includes a positive metal foil and a positive active material layer. A positive active material-free portion is formed on a first end of the positive electrode. The positive active material layer extends to a second end. The negative electrode includes a negative metal foil and a negative active material layer. A negative active material-free portion is formed on a third end of the negative electrode. The negative active material layer extends to a fourth end. Each of the first and second separator portions includes a strong bonding portion and a weak bonding portion. The strong bonding portion is located proximate to the first end and extends along the first end. The weak bonding portion is located proximate to the second end and extends along the second end.

Abstract: A secondary battery includes an electrode assembly including a pair of electrodes separated from each other by a separator, a battery case including a front portion bonded to a back portion to produce wing portions at opposite edges of the battery case, the electrode assembly being arranged within an accommodating portion of the battery case, the accommodating portion being arranged between the wing portions, an insulating member arranged at each of said wing portions of the battery case and a bonding portion arranged at each of said wing portions to attach said wing portions to the accommodating portion of the battery case. The bonding portion may be a double sided tape and may be integrally provided with the insulating member to simplify manufacturing process thereof.

Abstract: Provided is a separator incorporating an electrode, provided with two of separator sheets facing each other, an electrode sandwiched between the separator plates. Each of the facing surfaces of the separator sheets is provided with a coated portion coated with a ceramic, and a non-coated portion that is not coated with the ceramic, located in at least a portion of ranges corresponding to peripheral edges of the electrode. The separator sheets are joined to one another in the non-coated portion.

Abstract: In a method for manufacturing a packed electrode, an electrode is set between two separation layers that are made of resin, a heat-resistant layer is set between at least one of the two separation layers and the electrode, the two separation layers, the electrode and the heat-resistant layer, an overlapped portion of the two separation layers overlapped with the heat-resistant layer interposed therebetween is pinched, pressed and heated by a pair of heat sealing chips at an outside of the electrode, and the two separation layers are fastened by destroying the heat-resistant layer at the overlapped portion that are pressed and heated. According to the above manufacturing method, man-hours required for stacking can be reduced by integrating the heat-resistant layer with the packed electrode.

Abstract: A bipolar secondary battery has a battery element that includes first and second bipolar electrodes each having a collector disposed with a conductive resin layer containing a first resin as a base material and positive and negative electrode active material layers formed on opposite sides of the collector and a separator containing a second resin as a base material, arranged between the first and second bipolar electrodes and retaining an electrolyte material to form an electrolyte layer. The positive electrode active material layer of the first bipolar electrode, the electrolyte layer and the negative electrode active material layer of the second bipolar electrode constitute a unit cell. A melting point of the first resin is lower than or equal to a melting point of the second resin. Outer peripheries of the collectors of the first and second bipolar electrodes and an outer periphery of the separator are fused together to thereby seal an outer peripheral portion of the unit cell.

Abstract: Disclosed is a sealing material composition for a secondary battery, which is capable of providing a safe sealing layer that exhibits excellent adhesion in the sealing portion, while preventing leakage of the electrolyte solution. Specifically disclosed is a sealing material composition for a secondary battery, which is characterized by containing a diene rubber, a thermoplastic elastomer, carbon and an organic liquid material. The sealing material composition for a secondary battery is also characterized in that the number of coarse particles contained in 3 mL of the composition is 10 or less, said coarse particles having a maximum diameter of 10 ?m or more.

Abstract: The sealed battery has a battery container (4, 5) and a power generating element sealed inside the battery container. The battery container is provided with a fill opening (12), an annular ridge (16), which extends around the entire circumference of the outer face surrounding the fill opening, and an annular indentation (15) on the inside of the inner wall surface of the annular ridge, and has a sealing cap (8), which fits into the annular indentation and covers the fill opening. The sealing cap is joined by being welded to the inner wall surface of the annular ridge around the entire circumference at the edge thereof. Since heat is not well transferred from the inside to the outside of the outer wall surface of the annular ridge, the effective thermal capacity during welding is mostly determined by the structure of the area inside the outer wall surface of the annular ridge. Consequently, the effective thermal capacity is nearly uniform independent of direction.

Abstract: A flat nonaqueous secondary battery with improved reliability is provided. The flat nonaqueous secondary battery (1) includes an electrode assembly disposed in a space formed by an exterior case (2) and a seal case (3). The electrode assembly includes a plurality of positive electrodes (5) and a plurality of negative electrodes (6) alternately stacked upon each other and a separator (7). The separator (7) has a joint (7c) formed by welding together at least a portion of its periphery. When the separator (7) and the positive electrode (5) are measured along a cross section in their thickness direction, the ratio A/B of the shortest distance A between the end of the joint (7c) of the separator (7) facing the positive electrode (5) and the outer periphery of the positive electrode (5) sandwiched by the separator (7) to the thickness B of the positive electrode (5) is not smaller than 1.

Abstract: Disclosed herein is an electrochemical cell constructed in a structure in which a plurality of full cells or bicells, as unit cells, are folded by a separation film formed in the shape of a long sheet, and separators of the unit cells are secured to the separation film by thermal welding. The electrochemical cell according to the present invention has the effect of preventing the electrodes of the stacked electrodes from being separated from the separation film or from being twisted due to external impacts and vibrations, thereby restraining the electrochemical cell from generating heat or catching fire. Furthermore, the structural stability of the electrochemical cell is maintained even when the temperature of the electrochemical cell is increased, or the volume of the electrochemical cell is increased due to the generation of gas.

Abstract: A method of forming a secondary battery comprises: positioning an electrode assembly between a first pouch sheet and a second pouch sheet; initially sealing outer portions of the first pouch sheet and of the second pouch sheet on at least one side of the first and second pouch sheets; and additionally sealing outer portions of the first pouch sheet and of the second pouch sheet on the at least one side of the first and second pouch sheets.

Abstract: A rechargeable battery that includes: an electrode assembly generating a current; a case accommodating the electrode assembly therein; and a cap assembly coupled to the case so as to be electrically connected with the electrode assembly. The electrode assembly includes a first electrode, a separator, and a second electrode that are sequentially stacked, and the separator includes a main body part disposed between the first and second electrodes and protrusions formed that protrude from the main body part to the side of at least one of an end portion of the first electrode and an end portion of the second electrode.

Abstract: A rechargeable battery according to an exemplary embodiment of the present invention includes: an electrode assembly including a positive electrode, a negative electrode, a separator disposed between the positive and negative electrodes and having an expanded portion protruding to the outside of the positive and negative electrodes; a fixing member including a first support contacting a first outer side of the expanded portion, a second support contacting a second outer side, facing the opposite direction of the first outer side, and a joining portion joining the first and second supports; and a terminal electrically connected with the electrode assembly.

Abstract: Four sides of a rectangular bag-like separator 10 are composed of two adjacent separator thermo-bonding sides 10a and 10c where thermo-bonding portions are formed and of two adjacent insertion opening sides 10b and 10d forming one insertion opening 11 into which an electrode 30 can be inserted. A thermo-bonding section is formed in a portion of at least one of the insertion opening sides 10b and 10d.

Abstract: Disclosed herein is an electrochemical cell constructed in a structure in which a plurality of full cells or bicells, as unit cells, are folded by a separation film formed in the shape of a long sheet, and separators of the unit cells are secured to the separation film by thermal welding. The electrochemical cell according to the present invention has the effect of preventing the electrodes of the stacked electrodes from being separated from the separation film or from being twisted due to external impacts and vibrations, thereby restraining the electrochemical cell from generating heat or catching fire. Furthermore, the structural stability of the electrochemical cell is maintained even when the temperature of the electrochemical cell is increased, or the volume of the electrochemical cell is increased due to the generation of gas.

Abstract: A rechargeable battery comprises: an electrode assembly comprising a plurality of positive electrode plates, a plurality of negative electrode plates, and a plurality of separators; and a case enclosing the electrode assembly; wherein each separator in the plurality of separators comprises a central portion facing at least one of the positive and negative electrode plates, and an extended portion that extends past the positive and negative electrode plates, and wherein each of the extended portion comprises an adhered portion that is adhered to adjacent extended portions.

Abstract: A battery separator for a lead acid (storage) battery is made from a thermoplastic sheet material. The sheet material has a central region flanked by peripheral regions. The central region includes a plurality of longitudinally extending ribs that are integrally formed from the sheet material. The peripheral regions are free of ribs and may include a densified structure. Also disclosed are a method of producing the foregoing separator, an envelope separator made from the sheet material, and a method of making the envelope separator.

Abstract: Provided is a battery which can reduce expansion caused by gas emission when stored at high temperature. A secondary battery (1) is constructed such that a flat wound electrode (20) as a power generating element is sandwiched between exterior members (30a, 30b), having adhesion layers (40a, 40b) interposed therebetween. The adhesion layers (40a, 40b) are, for example, two-sided adhesive tapes and have a structure such that adhesive layers are formed on both surfaces of a thin plate-shaped support layer. The support layer is preferably made of polypropylene or polyimide. The adhesion layers (40a, 40b) are composed of maleated polypropylene whose melting point is preferably in a range from 100° C. to 200° C., more preferably, in a range from 140° C. to 180° C.

Abstract: The present invention provides a bipolar battery made by using a polymer gel electrolyte or a liquid electrolyte in an electrolyte layer, which is highly reliable and prevents liquid junction (short circuit) caused by leak out of an electrolyte solution from the electrolyte part. The present invention provides a bipolar battery laminated, in series, with a plurality pieces of bipolar electrodes which is formed with a positive electrode on one surface of a collector, and a negative electrode on the other surface, so as to sandwich an electrolyte layer, characterized by being provided with a separator which retains the electrolyte later, and a seal resin which is formed and arranged at the outer circumference part of a part of the separator where the electrolyte is retained.

Abstract: A battery separator for a lead acid (storage) battery is made from a thermoplastic sheet material. The sheet material has a central region flanked by peripheral regions. The central region includes a plurality of longitudinally extending ribs that are integrally formed from the sheet material. The peripheral regions are free of ribs and may include a densified structure. Also disclosed are a method of producing the foregoing separator, an envelope separator made from the sheet material, and a method of making the envelope separator.

Abstract: A battery unit and a lithium secondary battery employing the same are provided. The battery unit includes a positive electrode plate having a positive current collector and a positive active material layer formed on at least one plane of the positive current collector, a positive electrode lead electrically connected with the positive current collector, a negative electrode plate having a negative current collector and a negative active material layer formed on at least one plane of the negative current collector, a negative electrode lead electrically connected with the negative current collector, and a separator interposed between the positive electrode plate and the negative electrode plate, having a width greater than that of each electrode plate, and having different widths of protruding portions which stick out on either side of the electrode plate.

Abstract: A stacked secondary cell suppresses heat contraction of the opening of a sack-shaped separator even in a high-temperature environment and prevents the occurrence of short circuits between the stacked electrodes. In the disclosed stacked secondary cell, positive electrodes (13) and negative electrodes each having a lead-out terminal (2) are alternately stacked with interposed separators (15). Of positive electrodes (13) and negative electrodes, at least electrodes of one polarity are each housed in sack-shaped separator sacks (15) each formed by two sheet-shaped separators that are bonded together with an opening (3) in one portion. Further, the lead-out terminal (2) of the electrode (13) that is housed in the separator sack (15) protrudes through the opening (3) to the exterior of the separator sack (15), and the outer periphery of the opening (3) is covered by an electric insulating layer (8).

Abstract: A gasket for sealing internal surfaces of a fuel cell and formed of compressible material, the gasket comprising a first sealing surface and a second sealing surface for providing a fluid seal against opposing faces of a first fluid flow field plate and a second fluid flow field plate respectively, the gasket further comprising a third sealing surface for sealing against an outer perimeter region of a first surface of a membrane electrode assembly, the third sealing surface being entirely enclosed within a boundary defined by an inner perimeter of the second sealing surface.

Abstract: An electrode terminal 42 is connected to a current collector part 12 of electrodes through a deformation restricting member 3. Between laminate films 2 and 2, a space 15 is formed above and below the current collector part 12. The deformation restricting member 3 is placed close to the inner wall peripheral portion of an outer package including sealing parts 23, thereby forming a deformation-restricting part 22 to restrict the inward deformation of the laminated films 2. In a section extending from the inside end of the deformation restricting member 3 to a battery element 1, the laminated films 2 face the space 15 to allow the deformation of the laminated films 2 in response to the change of internal pressure. At the decrease of internal pressure, the contraction of the laminated films 2 can be localized in the deformation-allowing part 21, thereby reducing the bending stress on an end portion of the sealing parts 23.

Abstract: A flat nonaqueous secondary battery with improved reliability is provided. The flat nonaqueous secondary battery (1) includes an electrode assembly disposed in a space formed by an exterior case (2) and a seal case (3). The electrode assembly includes a plurality of positive electrodes (5) and a plurality of negative electrodes (6) alternately stacked upon each other and a separator (7). The separator (7) has a joint (7c) formed by welding together at least a portion of its periphery. When the separator (7) and the positive electrode (5) are measured along a cross section in their thickness direction, the ratio A/B of the shortest distance A between the end of the joint (7c) of the separator (7) facing the positive electrode (5) and the outer periphery of the positive electrode (5) sandwiched by the separator (7) to the thickness B of the positive electrode (5) is not smaller than 1.

Abstract: A winding electrode body is provided which includes a belt-shaped positive electrode, a belt-shaped negative electrode, and two belt-shaped separators. In the above winding electrode body, the two separators are laminated with the positive electrode and the negative electrode are wound in the state that positive electrode and the negative electrode are interleaved by the intermediate portions of the two separators in the longitudinal directions thereof, start edges of the two separators extending past the intermediate portions are disposed to face each other in a free edge state at a position at which the positive electrode and the negative electrode are not provided, and end edges of the two separators extending past the intermediate positions are disposed and fixed to each other at a position at which the positive electrode and the negative electrode are not provided.

Abstract: A stack type battery has a positive electrode plate (1) having a positive electrode active material layer (1a) formed on at least one side of a current collector made of a metal plate and a positive electrode current collector lead (11) provided in a portion thereof, the positive electrode plate (1) and the positive electrode current collector lead (11) facing a negative electrode plate across a separator (3a). A protective layer (13) made of a material having a lower electron conductivity than the metal of the current collector and being non-insulative is formed at a portion of the positive electrode plate (1) between the positive electrode current collector lead (11) and the separator (3a). The positive, electrode current collector lead (11) and the separator (3a) are joined to each other by the protective layer (13).

Abstract: An electrode assembly for a secondary battery that includes pressing parts are formed on separators surrounding positive and negative electrodes so that the electrode assembly can be bent in a zigzag shape to form a stacked structure, and thus the thermal stability of the electrode assembly can be improved and the stacked structure of the electrode assembly can be easily formed. In addition, electrolyte can easily permeate the electrode assembly. The electrode assembly includes separators, positive and negative electrode plates disposed between the separators, and pressing parts formed on the separators between the positive and negative electrode plates. Guide parts are formed at the pressing parts, and the separators are bent at the guide parts.

Abstract: A method for forming an electrode plate for a battery includes the steps of (a) forming mixture layers on a current collector, lateral end surfaces of the mixture layers forming a continuous plane with at least one lateral end surface of the current collector; and (b) forming a porous film on the mixture layers.

Abstract: A battery unit and a lithium secondary battery employing the same are provided. The battery unit includes a positive electrode plate having a positive current collector and a positive active material layer formed on at least one plane of the positive current collector, a positive electrode lead electrically connected with the positive current collector, a negative electrode plate having a negative current collector and a negative active material layer formed on at least one plane of the negative current collector, a negative electrode lead electrically connected with the negative current collector, and a separator interposed between the positive electrode plate and the negative electrode plate, having a width greater than that of each electrode plate, and having different widths of protruding portions which stick out on either side of the electrode plate.