Abstract: A battery container, a battery pack, and a vehicle are provided. The battery container includes a battery compartment and a first beam. The battery compartment is configured to accommodate a plurality of batteries. The batteries are arranged along a first direction. The first beam extends along the first direction and forms a first side wall of the battery compartment. A first adhesive receiving groove is recessed from an inner wall of the first beam. The first adhesive receiving groove extends along the first direction. The first adhesive receiving groove is configured to be filled with a connection adhesive to connect the first beam to the batteries. The inner wall of the first beam is a side wall of the first beam facing the batteries.

Abstract: Pouch cell having a positive contact lug and a negative contact lug, in which contact lugs electrical contact can be made with the pouch cell pouch cell and the pouch cell can be charged and discharged in this way, wherein the pouch cell is of planar design and has a flat cell surface which extends parallel in relation to the positive contact lug and the negative contact lug, wherein the positive contact lug has an upper positive connecting element and a lower positive connecting element, which positive connecting elements are arranged on opposite sides of the positive contact lug, and the negative contact lug has an upper negative connecting element and a lower negative connecting element, which negative connecting elements are arranged on opposite sides of the negative contact lug.

Abstract: An all-solid battery includes at least a unit cell including a positive electrode, a negative electrode, and an ion-conductive solid electrolyte layer interposed between the positive electrode and the negative electrode. The solid electrolyte layer includes an inorganic solid electrolyte, and a resistance R1 of the unit cell when the pressure applied in a thickness direction of the unit cell is 100 kPa is 90 ?cm2 or less.

Abstract: A bipolar lead acid battery with increased energy density is provided. The battery includes a number of lead acid wafer cell that each comprise a negative electrode having a negative electrode plate and a negative active material positioned on the negative electrode plate, as well as a positive electrode having a positive electrode plate and a positive active material positioned on the positive electrode plate. The positive electrode plate comprises a metal foil with a conductive film thereon, such as a titanium foil or substrate with a titanium silicide coating thereon. The lead acid wafer cell also includes a separator between the negative and positive electrodes, wherein the separator includes an electrolyte for transferring charge between the negative and positive electrodes.

Abstract: An electrode includes a unit body stack part formed by stacking at least one basic unit having a four-layer structure in which a first electrode, a first separator, a second electrode and a second separator are sequentially stacked. Each surface of the first separator and the second separator is coated with a coating material having adhesiveness, and the basic unit adheres to an adjacent radial unit in the unit body stack part. The electrode assembly of allows a heating and pressing process to be performed prior to a primary formation process so that a separator of one basic unit and a first electrode of the other basic unit to be adhered and fixed by a coating material coated on the separator, and thus a bending phenomenon caused by a difference in electrode expansion rates in a charging/discharging process is prevented.

Abstract: Provided is a lithium-ion assembled battery in which two or more single cells are laminated and the DC resistance value between the single cells is low.

Abstract: A battery pack including m number of battery cells arranged in a first direction; and spacers on the battery cells, the spacers each including a plurality of spacer units arranged in the first direction, wherein each of the spacer units extends across n number of battery cells, in which n<m, and each of the spacer units includes a plurality of spacing bars, each spacing bar being between adjacent ones of the battery cells, and connection bars connecting the plurality of spacing bars to each other.

Abstract: A method for manufacturing the electrode assembly includes: a first step of preparing a plurality of radical units, each of which is manufactured by alternately stacking an electrode and a separator; a second step of stacking the plurality of radical units to manufacture an electrode stack; and a third step of pressing an outer surface of the electrode stack to manufacture an electrode assembly on which a curved surface having a curvature radius is formed on the electrode stack, wherein, when the sum of bonding force remaining after the third step among bonding force between the electrode and the separator as bonding force generated before the third step is defined as F1, the sum of force by which the electrode and the separator are spread again so that shapes of the electrode and the separator return to shapes before the electrode stack is pressed in the third step is defined as R, and the sum of bonding force additionally generated between the electrode and the separator within the electrode assembly by the

Abstract: A positive electrode material contains a positive electrode active material and a first solid electrolyte material. The first solid electrolyte material is represented by Chemical Formula (1): Li?M?X?. In Chemical Formula (1), ?, ?, and ? each represent a value larger than 0, M represents at least one element selected from the group consisting of metal elements other than lithium and of metalloid elements, and X represents at least one element selected from the group consisting of fluorine, chlorine, bromine, and iodine. The ratio of the volume of the positive electrode active material to the sum of the volume of the positive electrode active material and the volume of the solid electrolyte material is not less than 0.55 and not more than 0.85.

Abstract: A power supply device includes a plurality of rectangular battery cells stacked in the thickness direction, and a plurality of separators interposed between adjacent battery cells. The separator includes an insulating separator frame that forms a defined space surrounded in a frame shape, and a separator core that is inserted into the defined space surrounded by the separator frame and is disposed between the adjacent battery cells.

Abstract: To suppress heat generation in a stacked battery including a plurality of electric elements in internal short circuits and an unstable reaction when the battery is operated while an energy level is increased, the stacked battery includes a stack comprising a first current collector layer, a second current collector layer, a plurality of bipolar current collector layers that are arranged between the first and second current collector layers at intervals in the stacking direction, a plurality of electric elements, an anode active material layer, and an electrolyte layer that is arranged between the cathode and anode active material layers, where the ratio h/S (cm?1) of a length h (cm) between the one end face and the other end face in the stacking direction of the stack to an electrode area S (cm2) on a cross section orthogonal to the stacking direction of the stack is more than 1.

Abstract: An electrode assembly includes a cell stack part having (a) a structure in which one kind of radical unit is repeatedly disposed and has same number of electrodes and separators which are alternately disposed and integrally combined, or (b) a structure in which at least two kinds of radical units are disposed in a predetermined order, and an auxiliary unit disposed on at least one among an uppermost part or a lowermost part of the cell stack part. The one kind of radical unit of (a) has a four-layered structure in which a first electrode, a first separator, a second electrode and a second separator are sequentially stacked or a repeating structure in which the four-layered structure is repeatedly stacked, and each of the at least two kinds of radical units are stacked by ones in the predetermined order to form the four-layered structure or the repeating structure.

Abstract: A battery module made from a plurality of side-by-side pouch cell modules, wherein each pouch cell module is formed with a pair of cells on either side of an insulation pad with the cells in turn positioned between first and second metal brackets such that each cell contacts an insulation pad on one side and a metal bracket on the other. Also included are a pair of pressure plates at the ends of the stack of side-by-side pouch cells and a compression band wrapping around the plurality of side-by-side pouch cells and the pressure plates. A busbar electrically connects the plurality of side-by-side pouch cells together.

Abstract: A vehicle floor structure includes: a center floor; a plurality of longitudinal members attached to a bottom surface of the center floor; and a battery assembly having a battery case disposed under the center floor and a through bolt passing through the battery case, wherein the through bolt is vertically aligned with respect to at least one longitudinal member among the plurality of longitudinal members, and the through bolt is joined to the at least one longitudinal member.

Abstract: An electrode for a secondary battery that includes a collector and an active material layer formed on the collector. The active material layer is configured of a plurality of layers including at least a first layer formed on the collector, and a second layer formed on the first layer. An end portion of the collector at an edge portion of the electrode is widened in an electrode thickness direction with respect to a plate thickness of the collector.

Abstract: An electrode assembly including an electrode stack including a plurality of radical units including an electrode and a separator and having a structure in which the plurality of radical units are sequentially stacked, wherein at least a portion of a circumference of the electrode stack is surrounded by the separator, a curved surface having a curvature radius is formed on a top or bottom surface of the electrode stack, and the separator surrounding at least the portion of the circumference of the electrode stack surrounds the curved surface formed on the electrode stack to maintain a relative distance between the radical units adjacent to each other is provided. A method of forming the electrode assembly is also provided.

Abstract: An electrode assembly includes a fan-folded multilayer containing a separator as an inner layer, current collectors as outer layers, and electrode material between the two sides of the separator and the current collectors, and a first terminal that is attached to the upward folds of the fan-folded multilayer and a second terminal that is attached to the downward folds of the fan-folded multilayer. An energy storage device includes the electrode assembly.

Abstract: A battery enclosure is provided having unswitched positive and negative terminals that are physically separated. The unswitched positive and negative terminals may be connected to circuit protection components, such as contactors and fuses. The contactors are set to an opened or closed state via a contactor control module. The battery enclosure includes external terminals that electrically couple the battery and circuit protection devices to external components, such as charging ports and electrical loads.

Abstract: A solid-state battery includes a third active material layer, a first solid electrolyte layer, a first active material layer, a first current collector layer, a second active material layer, a second solid electrolyte layer and a fourth active material layer in the order mentioned, wherein both the first and second active layers are anode or cathode active material layers. When both the first and second active layers are anode layers, both the third and fourth active layers are cathode layers. When both the first and second active layers are cathode layers, both the third and fourth active layers are anode layers, at least the first current collector layer extends to an outer side than the third and fourth active layers, and an insulating resin layer continuously across a surface of the extending part on one side, a side face and a surface of the extending part on the other side.

Abstract: Disclosed herein is an electrode assembly configured to have a structure in which a bi-cell and two or more monocells are folded in a state in which the bi-cell and the two or more monocells are arranged on a continuous separation film. The bi-cell includes electrodes in the form of at least one cathode and at least one anode stacked so that a separator is disposed between the cathode and the anode, the bi-cell having a first dimension in a first direction substantially equal to w. The two or more monocells each include electrodes in the form of at least one cathode and at least one anode stacked so that a separator is disposed between the cathode and the anode, each cathode and each anode of each monocell having a first dimension in the first direction substantially equal to 2 times the first dimension w of the bi-cell.

Abstract: Provided by the present disclosure is a batten pack in which both battery performance and durability of an all solid state battery are improved. Provided is a battery pack provided with a plurality of single batteries and a constraining mechanism. The constraining mechanism constrains the arranged single batteries in such a way that stress exists in the direction of compression along the arrangement direction. In addition, in a direction which intersects the arrangement direction, when a direction in which the external connection terminals extend is deemed to be a first direction and the direction opposite the first direction is deemed to a second direction, the constraining mechanism is configured in such a way that the stress increases from the first direction towards the second direction.

Abstract: A spacer (first spacer 114) has an insulating property, is used in a battery pack 100, obtained by electrically interconnecting unit cells 110 that are stacked one atop another, by means of a bus bar 132 along the stacking direction (Z direction) of the unit cells, each having a cell body 110H, which includes a power-generating element 111 and is formed in a flat shape, and an electrode tab 112, which is drawn out from the cell body 110H and whose distal end portion 112d is folded along the thickness direction of the cell body 110H; and is provided between each of the unit cells. The first spacer has an abutting portion 114h, a recessed portion 114i, and a communicating portion 114j. The abutting portion abuts the distal end portion of the electrode tab along the stacking direction of the unit cells. The recessed portion is recessed in a direction intersecting the stacking direction of the unit cells so as to be separated from the distal end portion of the electrode tab.

Abstract: A battery module having a battery cell assembly that is free from module banding is provided. The assembly includes an expandable battery cell having a first and second face. The assembly further includes a growth plate having a first and second face. The first face of the battery cell contacts the second face of the growth plate. The battery cell assembly further includes a first cell frame securing the growth plate on at least two sides and a second cell frame that contacts the second face of the battery cell. The first face of the growth plate includes a plurality of spacing features disposed along the first face of the growth plate that offset the first face of the growth plate from the first cell frame, which creates a cavity between the growth plate and the first cell frame. The cavity decreases when the battery cell expands.

Abstract: A method for manufacturing an all-solid state secondary battery including a plurality of provisional battery bodies, the method including: forming each of the plurality of provisional battery bodies by pressing a positive-electrode mixture, a solid electrolyte, and a negative-electrode mixture that are stacked between a pair of electrode current collectors and pressure-molding the stacked provisional battery bodies with the electrode current collectors facing each other. The electrode current collectors facing each other have rough surfaces.

Abstract: [SUMMARY] [OBJECT] To provide an all-solid-state battery in which the occurrence of short-circuiting can be prevented and in which damage to the electrode can be prevented, and a method for producing the all-solid-state battery.

Abstract: A manufacturing method of a battery structure is provided. A packing is provided, wherein the packing pre-forms an accommodating space. A first battery unit is disposed into the accommodating space, wherein the first battery unit includes at least one anode and at least one cathode alternately stacked with each other and a dielectric layer located between the anode and the cathode. A separation membrane is disposed into the accommodating space and located on the first battery unit. A second battery unit is stacked onto the separation membrane, located in the accommodating space and includes at least one anode and at least one cathode alternately stacked with each other and a dielectric layer located between the anode and the cathode. A dimension of the first battery unit is smaller than a dimension of the second battery unit. Electrolytes is injected into the accommodating space. The packing is sealed.

Abstract: This application describes a process for the preparation of flexible electrode-separator elements or assemblies, which includes the application of an electrode material on the separator. The electrode material comprises graphene, for instance produced by graphite exfoliation. The electrode-separator elements obtained by the process as well as their use in electrochemical cells are also described.

Abstract: A power storage device having flexibility is provided. A power storage device of which the capacity is not likely to deteriorate even when being curved is provided. A power storage device includes a first electrode, a second electrode, and an electrolytic solution. The first electrode and the second electrode overlap with each other. The first electrode includes a first current collector and a first active material layer. The first current collector has a first surface and a second surface. The first active material layer is provided on the first surface. The first current collector has a first bent portion with the second surface inside. The second surface includes a first region and a second region. The first region overlaps with the second region. The first region is connected to the second region at a portion different from the first bent portion.

Abstract: An electrode assembly for a solid state battery includes a positive electrode, a negative electrode and a solid electrolyte layer interposed between the positive electrode and the negative electrode. In addition, the binder disposed at the interface between the negative electrode and the solid electrolyte layer, the interface between the positive electrode and the solid electrolyte layer and/or at a predetermined depth from the interface is crosslinked to form a three-dimensional network. In other words, in the electrode assembly, the binder contained in the negative electrode and the solid electrolyte layer and/or the binder contained in the positive electrode and the solid electrolyte layer is crosslinked to improve the interfacial binding force between the negative electrode and the solid electrolyte layer and/or between the positive electrode and the solid electrolyte layer, and thus ion conductivity is maintained to a significantly high level.

Abstract: An electrochemical device positive electrode with a lead member includes a positive electrode and a lead member attached to the positive electrode. The positive electrode includes a positive current collector, a carbon layer, and an active layer. The carbon layer is disposed on a surface of the positive current collector, and contains a conductive carbon material. The active layer is supported by the positive current collector via the carbon layer disposed between the active layer and the positive current collector, and contains a conductive polymer. The lead member is in contact with the carbon layer.

Abstract: An assembled battery disclosed herein includes a plurality of battery cells and a plurality of heat transfer plates. The plurality of battery cells are laminated in a prescribed direction. The plurality of heat transfer plates are arranged on both sides in the direction of lamination of each of the plurality of battery cells. As two battery cells adjacent to each other among the plurality of laminated battery cells, two adjacent battery cells connected in series and two adjacent battery cells connected in parallel are included, and an insulating material for insulating the adjacent battery cells from each other is arranged between the two adjacent battery cells connected in series among the two battery cells adjacent to each other but the insulating material is not arranged between the two adjacent battery cells connected in parallel among the two battery cells adjacent to each other.

Abstract: The present invention relates to an electrode assembly in which a plurality of electrode units are stacked to improve product stability when manufactured and a method for manufacturing the same. In addition, the present invention is provided to include a plurality of electrode units on which electrode tabs are formed and a full length-side separator member folded in a direction in which the electrode tabs are formed and a direction opposite to the direction in which the electrode tabs are formed while stacking the plurality of electrode units to be separated from each other.

Abstract: A structural component for a vehicle has a battery construction having a solid-electrolyte matrix material, a first layer of carbon fibres having a cathode-active coating, embedded in said solid-electrolyte matrix material, a second layer of carbon fibres without a cathode-active coating, embedded in said solid-electrolyte matrix material, and at least one electrically isolating barrier layer disposed between said first layer and said second layer. The structural component has a first collector layer and a second collector layer disposed on the first layer and the second layer, respectively, on a side that faces away from the barrier layer. The first collector layer and the second collector layer are configured from a flexible, moldable and porous layer of carbon allotropes.

Abstract: A battery includes first and second power generating elements laminated to each other. In the first power generating element, the inner layer of a first electrode current collector is in contact with a first electrode active material layer. In the second power generating element, the inner layer of a second electrode current collector is in contact with a second electrode active material layer. The outer layers of the first electrode current collector and the second electrode current collector are in contact with each other. The inner layer of the first electrode current collector contains a first material; the inner layer of the second electrode current collector contains a third material different from the first material; the outer layer of the second electrode current collector contains a second material different from the first material; and the outer layer of the first electrode current collector contains the second material.

Abstract: Improved battery separators are disclosed herein for use in flooded lead-acid batteries, and in particular enhanced flooded lead-acid batteries. The improved separators disclosed herein provide for enhanced electrolyte mixing and substantially reduced acid stratification. The improved flooded lead-acid batteries may be advantageously employed in applications in which the battery remains in a partial state of charge, for instance in start/stop vehicle systems. Also, improved lead-acid batteries, such as flooded lead-acid batteries, improved systems that include a lead-acid battery and a battery separator, improved battery separators, improved vehicles including such systems, and/or methods of manufacture and/or use may be provided.

Abstract: A battery module includes a plurality of battery cells stacked on one another, a cell housing configured to accommodate the plurality of battery cells, a top plate configured to cover an entire upper side of the cell housing and electrically connected to any one of positive electrodes and negative electrodes of the plurality of battery cells, and a bottom plate disposed to face the top plate and configured to cover an entire lower side of the cell housing and electrically connected to the other of the positive electrodes and the negative electrodes of the plurality of battery cells.

Abstract: An assembled battery includes non-aqueous electrolyte batteries laminated with each other and at least one lead being interposed between two adjacent batteries. The lead is connected to the two adjacent batteries and has an area larger than that of a side surface of each battery, the side surface being opposing to the lead. Each battery includes at least one positive electrode, at least one negative electrode and a non-aqueous electrolyte. The positive electrode includes a current collector and positive electrode active material layers provided on both side surfaces of the collector. The negative electrode includes a negative electrode current collector and negative electrode active material layers provided on both side surfaces of the collector.

Abstract: A battery includes a current collector, first electrode layer, first counter electrode layer, and second electrode layer. The current collector includes a first electroconductive portion, first insulating portion, and second electroconductive portion. The second electroconductive portion includes a first edge region, first front face region, first rear face region, first fold portion, second front face region, second rear face region, and second edge region. The first and second rear face regions face each other by the current collector being folded. The first electrode layer is disposed in contact with the first electroconductive portion, the first counter electrode layer in contact with the first front face region, and the second electrode layer in contact with the second front face region. The first insulating portion links the first electroconductive portion and first edge region. The first electrode layer and first counter electrode layer face each other by the current collector being folded.

Abstract: The application discloses a hard-shell flexibly-packaged capacitor module and a system, including: a flexibly-packaged individual capacitor and fastening plates, including a first fastening plate and a second fastening plate being oppositely mounted and connected in clasped manner; and, supports including a first support and a second support being oppositely mounted and used for connecting the individual positive and negative tabs respectively; and the two supports and the two fastening plates being enclosed to form a closed structure for accommodating the individual capacitor. Individual capacitors and a silica gel insulator are assembled inside the fastening plates clasped with each other, i.e. a “hard-shell” structure is provided for the individual capacitors; the hard-shell flexibly-packaged capacitor module is assembled as a whole, and multiple capacitor modules are connected in series or in parallel to form a required capacitor system, it is good in expansibility and easy to assemble.

Abstract: According to the present disclosure, there is provided an electrode assembly comprising (a) a structure in which one kind of radical unit is repeatedly disposed, the one kind of radical unit having a same number of electrodes and separators which are alternately disposed and integrally combined, or (b) a structure in which at least two kinds of radical units are disposed in a predetermined order, the at least two kinds of radical units each having a same number of electrodes and separators which are alternately disposed and integrally combined.

Abstract: An energy storage apparatus includes: one or more energy storage devices; an outer case; and a plate-like spacer disposed between the energy storage device at an end among the above-mentioned one or more energy storage devices and the outer case.

Abstract: The present invention relates to a secondary battery in which a stacked electrode assembly having a cathode, an anode and a separator is accommodated together with an electrolytic solution between exterior members. In the present invention, the secondary battery has a plurality of joint parts at which the outer peripheral portion of the separator is joined with the exterior members and a holding part formed at least between the joint parts so as to hold therein the electrolytic solution, wherein a sum of perimeters of the joint parts is longer than a perimeter of a rectangle of minimum area enclosing therein all of the joint parts. In this configuration, it is possible to refill the stacked electrode assembly with the electrolytic solution and protect the joint parts from breakage while preventing displacement of the stacked electrode assembly in the secondary battery.

Abstract: The present invention relates to a secondary battery in which a stacked electrode assembly having a cathode, an anode and a separator is accommodated together with an electrolytic solution between exterior members. In the present invention, the secondary battery has a plurality of joint parts at which the outer peripheral portion of the separator is joined with the exterior members and a holding part formed at least between the joint parts so as to hold therein the electrolytic solution, wherein a sum of perimeters of the joint parts is longer than a perimeter of a rectangle of minimum area enclosing therein all of the joint parts. In this configuration, it is possible to refill the stacked electrode assembly with the electrolytic solution and protect the joint parts from breakage while preventing displacement of the stacked electrode assembly in the secondary battery.

Abstract: Wireless headphones having a built-in flexible battery are provided. Wireless headphones having a built-in flexible battery according to an exemplary embodiment of the present invention comprise: a band part having at least one fastening portion; a pair of headset parts, each of which includes a speaker unit for receiving a wirelessly transmitted audio signal and outputting the audio signal to the outside, and is connected to the band part; and a plate-shaped flexible battery which is embedded in the band part so as to supply power to the headset parts, and has a to-be-fastened portion corresponding to the fastening portion so as to be fixed in position when coupled to the band part.

Abstract: A battery module incorporates features of both prismatic housings and metal foil laminate pouch housings, and is configured to receive and support electrochemical cells. The battery module housing includes a rigid tubular frame and flexible cover elements that are joined to the frame and close the open ends of the frame. The frame has an inner surface that faces the cells, an outer surface that is opposed to the inner surface, a first edge that joins the inner surface to the outer surface at one open end of the frame, and a second edge that joins the inner surface to the outer surface at the opposed open end of the frame. The first cover element overlies and closes the one open end of the frame and the second cover element overlies and closes the other open end of the frame.

Abstract: A battery module includes a plurality of flat or square type batteries that each have a positive terminal and a negative terminal; a holder that has an opening, and retains the batteries in such a manner that the positive terminal and the negative terminal are positioned toward the opening, and that the principal surfaces of the batteries face each other; a cover that is disposed over the opening; a circuit board that is disposed over the cover; and a plurality of connection members that are disposed between the cover and the circuit board to electrically connect the positive terminal and negative terminal. Some of the connection members retain a peripheral portion of the circuit board.

Abstract: Electrochemical device 1 includes: electric storage element 5 that includes positive electrode 2, negative electrode 3 and a plurality of separators 4, positive electrode 2 and negative electrode 3 overlapping each other with separators 4 interposed therebetween; and outer container 8 that is composed of flexible film 7, outer container 8 containing electric storage element 5. Separators 4 include adhesive separator 4a and heat-resistant separator 4b whose melting point is higher than the melting point of adhesive separator 4a, and at least a part of adhesive separator 4a is welded to flexible film 7 that makes up outer container 8.

Abstract: A conventional bipolar battery is constituted of a combination of cells hermetically sealed for preventing a liquid junction and preventing corrosion of a peripheral device due to a liquid leakage. Therefore, electrolytic solution injecting processes are carried out as many as the number of cells, so that much times and costs have been required for manufacturing a large-scale battery. In addition, a wiring space has been required since the cells are connected to one another with wires. The use of a current collector formed of a one-end closed tubular conductor, the current collector having a bottom protruding outward to form a protrusion, eliminates the wiring space and achieves a reduction in ohmic loss due to the wires. In addition, an electrolytic solution in one cell is separated by a water-repellent sheet from an electrolytic solution in another cell, so that a liquid junction is prevented.

Abstract: Disclosed is a battery module, which comprises a cell assembly including a plurality of battery cell groups, in each of which a plurality of battery cells respectively having protrusions protruding in a left and right direction on at least one of one end and the other end thereof are stacked in an upper and lower direction, wherein the protrusion of any one battery cell group among the plurality of battery cell groups is inserted and coupled between the protrusions of another battery cell group, wherein a step is formed between adjacent battery cell groups in an upper and lower direction; and end plates respectively disposed at upper and lower portions of the cell assembly.

Abstract: A battery includes a first current collector, first electrode layer, and first counter electrode layer. The first counter electrode layer is a counter electrode of the first electrode layer. The first current collector includes first front and rear face regions, second front and rear face regions, and a first fold portion. The first rear face region is a region situated on the rear face of the first front face region. The second rear face region is a region situated on the rear face of the second front face region. The first fold portion is situated between the first and second front face regions. The first current collector is folded at the first fold portion, whereby the first and second rear face regions face each other. The first electrode layer is in contact with the second front face region, and the first counter electrode layer with the first front face region.