Abstract: A high energy density battery is provided that improves energy density through efficient placement of the inter-plate connections within the battery enclosure. The placement of the current carrying leads in the high energy density battery allows for a greater volume of active material to be placed within the battery enclosure. This placement design can also be used to reduce the size of existing power sources. Methods for constructing high energy density batteries and methods for increasing the volumetric energy density of an implantable battery are also provided. The resulting high energy density battery can be used to power electronics associated with a variety of devices such as medical devices.

Abstract: A battery pack includes battery modules; battery module stacked members including the stacked battery modules; a battery module group including the battery module stacked members arranged in a plane; and a lower plate arranged to hold the battery module group. The lower plate includes a main body made from a resin, the main body supporting the battery module stacked members arranged in parallel, and including mounting surfaces each of which one of the battery module stacked members is mounted on; and metal frames each inserted and molded in one of the mounting surfaces, the metal frames being arranged in an arrangement direction of the battery module stacked members, and electrically insulated with each other.

Abstract: Disclosed herein is a process for preparation of a secondary battery module. The process includes forming coupling through-holes having specific shapes at plate-shaped electrode terminals of a plurality of unit cells, stacking the unit cells one on another, and inserting coupling members through the coupling through-holes to couple the unit cells with each other. Consequently, the secure coupling and the electrical connection between the unit cells is accomplished without using additional members, such as cartridges, and therefore, a compact battery module having high coupling force is prepared.

Abstract: A battery module is constructed with a plurality of unit batteries, and barrier ribs including bands mounted on each of the unit batteries and forming gaps to enable a heat conductive medium to circulate the unit batteries.

Abstract: Provided is a package for sodium-sulfur batteries in which the inner temperature can be suitably controlled even when it is installed in the place where temperatures and direction of wind change violently. Specifically, there is provided a package 101 for sodium-sulfur batteries in which air guiding plates 106a, 106b are provided being inclined obliquely and downwardly toward wall faces 109a, 109b between bottom surfaces of module batteries 4a, 4b and wall faces 109a, 109b, and in addition, flow rectifying plates 107a, 107b are provided being inclined obliquely and upwardly toward space 8 from the upper surface of module batteries 4a, 4b.

Abstract: The present invention provides a secondary battery module which is excellent in vibration resistance. A battery module 20 has assembled battery blocks 11 each constituted by screw-fixing the assembled batteries 2 to the block bases 3, 4 supporting a lower portion thereof and the two block reinforcing plates 5 supporting an upper portion thereof, the six assembled batteries 2 are sandwiched by and fixed firmly to the block bases 3, 4 and the block reinforcing plates 5. The assembled batteries 2 do not move freely even if vibration is added to the battery module 20. Because the elastic sheet 9 is laid between the block bases 3, 4 and the assembled batteries 2, since a space derived due to variance in size accuracy of frames 12 which hold and fix the unit cells 11 and derived due to variance in size accuracy of the block bases 3, 4 can be removed, and vibration resistance can be enhanced.

Abstract: A secondary battery is disclosed. In one embodiment, the secondary battery includes i) a first electrode plate having two opposing surfaces, wherein the first electrode plate comprises a first electrode collector and a first electrode coating portion disposed on at least one of the two surfaces of the first electrode collector and ii) a second electrode plate having two opposing surfaces, wherein the second electrode plate comprises a second electrode collector and a second electrode coating portion disposed on at least one of the two surfaces of the second electrode collector. The secondary battery may further include a separator disposed between the first and second electrode plates and electrically insulating the first and second electrode plates from each other.

Abstract: An electrode assembly and a secondary battery including the same. The electrode assembly includes a plurality of alternately disposed positive electrode plates and negative electrode plates, separators disposed between the positive electrode plates and the negative electrode plates, a plurality of positive electrode tabs formed in the plurality of positive electrode plates, a plurality of negative electrode tabs formed in the plurality of negative electrode plates, a positive electrode lead including a clip accommodating the plurality of positive electrode tabs and a lead line coupled to the clip, and a negative electrode lead including a clip accommodating the plurality of negative electrode tabs and a lead line coupled to the clip.

Abstract: A battery pack includes battery modules; battery module stacked members including the stacked battery modules; a battery module group including the battery module stacked members arranged in a plane; and a lower plate arranged to hold the battery module group. The lower plate includes a main body made from a resin, the main body supporting the battery module stacked members arranged in parallel, and including mounting surfaces each of which one of the battery module stacked members is mounted on; and metal frames each inserted and molded in one of the mounting surfaces, the metal frames being arranged in an arrangement direction of the battery module stacked members, and electrically insulated with each other.

Abstract: An individual cell for a battery comprises an electrode stack disposed within a cell housing and a method for the production thereof. The individual electrodes, preferably electrode foils, are electrically connected to lead vanes, and at least electrodes of different polarity are separated and insulated from each other by a separator preferably a separator foil. Lead vanes of the same polarity are electrically connected to each other to form a pole. The lead vanes of a pole are electrically compressed with each other and/or welded to each other.

Abstract: Apparatus and methodology subject matters relate to an improved electrochemical single or multi-cell energy storage device. Also, an outer casing may be provided as a pair of U-shaped shells, a single foil piece, or a tube-shaped structure which encases the internal electro chemical cell stack. The energy storage device and such casing when used advantageously exhibit low internal resistance, low ESR, a high voltage/capacity, and a low contact resistance between the internal stack and the outer casing.

Abstract: Provided are a secondary battery and a method for manufacturing the same. The secondary battery includes an electrode assembly and a pouch, the electrode assembly including a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode and insulating the first electrode and the second electrode from each other, the pouch configured to have a bottom face and lateral faces extending from edges of the bottom face and including a cavity to accommodate the electrode assembly. The pouch includes at least one alignment protrusion provided on its lateral face, and the electrode assembly including at least one alignment hole provided at its edge, the at least one alignment hole corresponding to the alignment protrusion of the pouch.

Abstract: A battery module is provided. The battery module includes a battery body having a plurality of unit cells arranged in series and having a respective barrier disposed between adjacent unit cells. End plates are disposed on opposite outermost sides of the battery body. A fixing unit fixes together the end plates and the battery body by enclosing an outer circumference of an assembly of the end plates and the battery body.

Abstract: Disclosed herein is a battery module having a plurality of plate-shaped battery cells which are sequentially stacked, wherein the battery module is configured in a structure in which two or more battery cell units are connected in series to each other in a state in which the battery cell units are stacked, each of the battery cell units is configured in a structure in which two or more battery cells are connected in parallel to each other in a state in which the battery cells are in tight contact with each other, the battery cells being mounted in housings, and external input and output terminals, i.e., a module cathode terminal and a module anode terminal, of the battery module are located at the same side or opposite sides of the battery module depending upon the number of the battery cell units constituting the battery module.

Abstract: The connection structure between unit cells connects a plurality of batteries B1 and B2 in series with bottomed cylindrical battery cases 2 and 5 which function as electrode terminals on one side, sealing plates 3 which close the opening portions of the battery cases 2 and 5 which function as electrode terminals on another side, and the first ring 1a with a flange is conductively connected at a bottom portion of a battery case 2 of one battery B1, the second ring 1b with a flange is conductively connected at an upper portion of the sealing plate 3 of another battery B2, and the first ring 1a and the second ring 1b are fitted.

Abstract: A lead acid electric storage battery uses conventional lead-acid secondary battery chemistry. The battery may be a sealed battery, an unsealed battery or a conventional multi-cellbattery. It has 12 to 25 cells in a single case. The case is less than 12 inches long and may be less than 6 inches long. The battery has a set of positive battery grids (plates) which are constructed with a core of thin titanium expanded metal having a thickness preferably, for start batteries etc. in the range 0.1 mm to 0.7 mm and most preferably 0.2 mm to 0.4 mm. The grid cores are of a titanium alloy containing a platinum group metal. The cores are coated with hot melt dip lead and are not lead electroplated. The grid cores expand and contract, with temperature changes, much less than conventional lead grids.

Abstract: A sealed rectangular battery excellent in volumetric efficiency and pressure resistance is provided. The sealed rectangular battery includes an electrode group having a positive electrode and a negative electrode and a cell casing for accommodating therein the electrode group and an electrolyte solution, which casing includes a rectangular frame member, a first lid member and a second lid member. Each of the first and second lid members includes a body portion for covering one of the openings of the frame member, and a side portion formed so as to protrude from the body portion substantially along at least one set of sides opposite to each other.

Abstract: A battery module is provided. The battery module includes a battery body having a plurality of unit cells arranged in series and having a respective barrier disposed between adjacent unit cells. End plates are disposed on opposite outermost sides of the battery body. A fixing unit fixes together the end plates and the battery body by enclosing an outer circumference of an assembly of the end plates and the battery body.

Abstract: A battery pack that includes a holder to accommodate bare cells and a lead plate electrically connected to the holder. The lead plate includes female and male coupling members such that the holder is easily assembled with the lead plate and an error occurring when the holder and the lead plate are coupled with each other may be prevented. The lead plate may not separate from the holder after assembling the holder with the lead plate.

Abstract: A battery assembly may include a battery and a battery housing. The battery may include an electrolyte vent to provide a pressurized electrolyte discharge during an electrolyte discharge event. The battery housing may contain the battery and may include an electrolyte control member to dissipate energy from and inhibit dispersion of the pressurized electrolyte discharge from the electrolyte vent during the electrolyte discharge event.

Abstract: A movable, portable, and instantly attachable/detachable battery pack includes batteries enclosed in a case with a ground transportation structure, such as wheels, coasters, and runners. The battery pack can include handles and mating connectors. The ground transportation structure allows the majority of the weight of the battery packs to be supported by the ground during transportation. The person who moves the battery pack only needs to use a minimum force sufficient to move the battery pack in a direction perpendicular to the force of gravity. Battery packs disclosed herein can be easily maneuvered into a building or structures to be recharged or swapped.

Abstract: A battery module is provided with a battery cell stack and a module case. The battery cell stack includes a plurality of stacked flat secondary battery cells. The module case includes an inwardly protruding section, a low rigidity section and a high rigidity section. The inwardly protruding section is disposed on at least one of two oppositely facing sides of the module case that faces in a battery cell stacking direction and protruding toward the interior area of the module case to apply pressure to an end surface of the battery cell stack. The low rigidity section elastically supports a periphery of the inwardly protruding section due the low rigidity section having a lower rigidity than the inwardly protruding section. The high rigidity section supports a periphery of the low rigidity section with the high rigidity section having a higher rigidity than low rigidity section.

Abstract: A prismatic rechargeable battery includes a housing comprising a plurality of cell vessels separated from one another by electrically insulating intermediate walls and a plate stack provided in each of the cell vessels, the plate stack comprising stacked electrode plates and a plurality of contacts. The battery also includes contact connector plates coupled to each of the intermediate walls such that each of the contact connector plates is in electrical contact with a contact of a plate stack. Each of the intermediate walls has a contact connector plate on a first side thereof electrically coupled to a contact connector plate on a second side thereof through the intermediate wall.

Abstract: The lithium-ion secondary battery has a portion where a thickness of a sealing member from a surface of an outer package to a surface of a lead in a laminating direction of electrode bodies on one side of the lead differs from that on the other side of the lead such that two leads connected to each electrode body are arranged within the same plane perpendicular to the laminating direction of the electrode bodies. The electrode bodies are laminated in the outer package such as to yield portions where only one of the planar leads of a first electrode body overlaps one of the planar leads of a second electrode body in the laminating direction of the electrode bodies in the opening part of the outer package.

Abstract: An interconnect device enables battery cells having terminals in the form of flexible tabs to be serially interconnected in a stack. The interconnect device comprises a relatively rigid substrate and at least two arrays of pins projecting from opposing first and second surfaces of the substrate. This enables the flexible tabs of the battery cell to be embedded in the pin arrays, providing a quick and easy means of fixing the tabs and enabling them to be interconnected to other cells in a stacked arrangement. A battery module formed from such a stack of cell assemblies is also disclosed.

Abstract: Disclosed herein is a structure of layering unit cells for a lithium polymer battery, in which electrode terminals are provided on surfaces of the respective unit cells for the lithium polymer battery, and are alternately layered, thus allowing the unit cells to be connected in series through only a layering operation without an additional connecting device. The battery system includes first and second unit cells each having a pouch and anode and cathode terminals which are connected to a surface of the pouch and are oppositely bent in upward and downward directions. In this case, the cathode terminal of the second unit cell is directly connected to the anode terminal of the first unit cell.

Abstract: A battery module is provided. The battery module includes a battery body having a plurality of unit cells arranged in series and having a respective barrier disposed between adjacent unit cells. End plates are disposed on opposite outermost sides of the battery body. A fixing unit fixes together the end plates and the battery body by enclosing an outer circumference of an assembly of the end plates and the battery body.

Abstract: The disclosure is directed to a battery assembly that includes a protective cover. The protective cover is positioned over a side plate that includes connections, such as a bus bar and a fixing member, that allow for battery operation. One or more flexible openings within the protective cover open to accept the fixing member, such as a screw or bolt, and close once the fixing member has passed. In this manner, the flexible opening allows for easy assembly and maintenance of the battery assembly while providing a mechanism of protecting the battery components from environmental elements. In addition, the flexible opening may be made by one or more cuts in the protective cover, wherein material elasticity enables the flexible opening to open and close.

Abstract: A package case is structured by a plurality of substantially identical and flat frames stacked on one another. Flat laminate cells (accumulator cells) are individually accommodated in the frames and stacked on one another, so that the number of flat laminate cells (accumulator cells) can readily be changed simply by increasing/decreasing the number of frames to be stacked to meet energy needs and the like. The accumulator device is segmented using the plurality of flat frames, so that externally applied impacts can readily be dispersed and the impact transmitted to the flat laminate cells (accumulator cells) can be reduced without reinforcing the accumulator device 1 with more than necessary strength.

Abstract: A fuel cell module includes a plurality of fuel cells, which are connected one behind the other and which are combined to form a fuel cell stack. The fuel cell module should be designed in such a manner that the magnetic field or leakage field, which can be detected in the outer area and which is generated during the operation of the fuel cell module, is held at a particularly low level. To this end, the materials used for providing the fuel cells themselves, the materials used for producing the connecting components or auxiliary components, which are assigned thereto, that connect these fuel cells, and the materials used for producing the housing are selected that have a relative magnetic permeability of less than 1.1.

Abstract: The present invention relates to a battery pack (10) having a housing (11) in which battery cells (12) are arranged and having electric contact elements (18) that are arranged on the housing (11). The battery pack also has a gas reservoir (15) and an output port (19) for gas that is connected to the gas reservoir (15) via a pressure line (16). Moreover, the invention relates to a hand-held power tool (30) having at least one electric consumer, having a cradle (31) for a battery pack (10), said cradle (31) comprising electric counter-contact elements (38) for the contact elements (18) of the battery pack (10), and said hand-held power tool having at least one device (35) that uses a gas that is under pressure. A connector (39) for an output port (19) of a gas reservoir (15) of the battery pack (10) is arranged on a cradle (31) of the hand-held power tool (30) for the battery pack (10), whereby said connector (39) is pneumatically connected to the device (35).

Abstract: A power storage unit includes a battery module housed in a battery case. The battery module has, as components, a plurality of battery cells stacked and arranged in a direction (direction Y) crossing a transverse direction. Reinforcing members arranged at a predetermined spacing are provided between the battery cells. The power storage unit of this structure can prevent damage to the power storage unit disposed between seats adjacent to each other in the transverse direction, when frame members provided in the seats are moved in the transverse direction in the event of a crash of a moving conveyance.

Abstract: Disclosed herein is a battery module constructed in a structure in which a cell stack, including a plurality of secondary battery cells (‘battery cells’) or a plurality of unit modules, each of which including a plurality of battery cells, stacked with high density, is mounted in a hexahedral module case, wherein the module case is provided at least one side thereof with a sliding coupling structure, and the battery module has a variable grip mounted thereto.

Abstract: A battery unit having at least two pouch type secondary battery cells and a single safety device serving each cell in the battery unit. Each individual battery or cell body fits into a space within a casing. The battery unit may use one or more casings. The battery cells are arranged such that the terminals of different battery cells are located near the terminals of other battery cells within the unit. These terminals are connected to the safety device. The safety device may be a safety circuit board that is positioned in a space within the battery unit so that the battery unit does not consume any more space than when no safety circuit board is used.

Abstract: One embodiment includes an electrical cell that includes a flat housing, at least one electrode and an electrically and heat conductive tab coupled to the electrode and extending through the housing for electrically and thermally coupling to a collector panel, the tab being capable of conducting both current and a substantial amount of heat out of the housing to a temperature control system. The cells may be stacked to form a battery having a temperature panel interfaced to the temperature control system by a thermal interface. The battery may propel an electrically-powered vehicle or the like.

Abstract: A flat secondary battery having a fusion-bonded sealing type laminate film as an armored body tends to be inferior in sealing reliability to a flat secondary battery having a welded sealing type can as an armored body, due to a difference in sealing method between the two batteries. Therefore, there has been a large challenge of finding the way to make the sealing reliability of the laminate film secondary battery closer to that of the can type secondary battery. The sealing reliability is improved by further increasing a sealing force without taking any measure to the existing laminate film secondary battery, in such a manner that the fusion bonding area of the existing laminate film secondary battery is sandwiched from upside and downside to be cramped from outside so as to mechanically add a sealing force from outside to the sealing force of the laminate film itself.

Abstract: A sealed prismatic battery has a battery case made of a plurality of prismatic cell cases coupled together via partition walls. Electrode plate groups are accommodated together with liquid electrolyte in each of the cell cases. Each electrode plate group consists of alternately stacked-up positive and negative electrode plates with separators interposed therebetween, lead portions of positive and negative electrode plates being protruded on opposite sides. Collectors are bonded to these lead portions. Between the collectors and end walls (and/or partition walls) of the battery case are provided conductive plates that are connected to the collectors one or more than one location in their middle part so as to decrease the resistance between connection terminals and the electrode plate groups.

Abstract: The battery system is provided with battery blocks 2 having a plurality of stacked battery cells 1, a pair of endplates 4 stacked at opposite ends of a battery block 2, connecting rails 5 that join the pair of endplates 4, and output lines 20 that connect to battery cell 1 electrode terminals 13. Output lines 20 are connected to battery cell 1 electrode terminals 13 via transfer bus bars 22, and an output line 20 connecting terminal 21 is connected to a transfer bus bar 22 by a bolt 7, and a nut 8. In this battery system, the nut 8 is attached to an endplate 4 in a manner that does not allow it to rotate, and the bolt 7 is screwed into the nut 8 to attach it to the endplate 4. The output line 20 connecting terminal 21 and transfer bus bar 22 are connected via the bolt 7 and nut 8 and are fixed to the endplate 4.

Abstract: Apparatus and methodology subject matters relate to an improved electrochemical single or multi-cell energy storage device. Also, an outer casing may be provided as a pair of U-shaped shells, a single foil piece, or a tube-shaped structure which encases the internal electrochemical cell stack. The energy storage device and such casing when used advantageously exhibit low internal resistance, low ESR, a high voltage/capacity, and a low contact resistance between the internal stack and the outer casing.

Abstract: A cell binder includes a frame body and a frame body. A storage portion of a electric storage cell are pressed/clamped by the bottom of an accommodating portion of the frame body and the bottom of an accommodating portion of the frame body. Also, a sealing portion of the electric storage cell is accommodated in a gap between the bottom of a fitting concave portion of the frame body 16 and the front end of a projecting portion of the other frame body, in a state of being deflected by bending, and the sealing portion is clamped between an inner wall of the fitting concave portion and an outer wall of the projecting portion, thereby fitting the frame bodies to each other. This makes it possible to reduce the size for clamping the sealing portion and to achieve the downsizing of the entire package. In addition, providing the sealing portion with deflections allows movements of the electric storage cell to be accommodated when vibrations are applied.

Abstract: A Battery Assembly comprises a rack assembly, a plurality of guiding strips, two polar heads, a plurality of lithium batteries and safety units. The guiding strips are connected to the polar heads and are disposed on the rack assembly, respectively. The rack assembly has a containing space for accommodating the lithium batteries, and each lithium battery is connected to the guiding strip by a guiding piece via one safety unit, such that the lithium batteries are connected in parallel, thus providing enough power with a small size. In addition, each safety unit can cut off the broken lithium battery separately, so as to avoid the immediate shut-off of the electric power.

Abstract: Disclosed herein is a battery module constructed in a structure in which a cell stack, including a plurality of secondary battery cells (‘battery cells’) or a plurality of unit modules, each of which including a plurality of battery cells, stacked with high density, is mounted in a hexahedral module case, wherein the module case is provided at least one side thereof with a sliding coupling structure, and the battery module has a variable grip mounted thereto.

Abstract: Disclosed herein is a middle- or large-sized battery module comprising a plurality of stacked unit cells, each unit module including two or more plate-shaped battery cells electrically connected with each other, each battery cell having electrode terminals formed at opposite sides thereof. The battery module is manufactured by connecting electrode terminals of a pair of unit modules by welding, mounting a sensing unit, including a sensing member, to the welding part and bending the welding part such that the unit modules are stacked, and repeatedly performing the above processes until all the unit cells are stacked.

Abstract: A battery compartment assembly includes a housing and a lid configured to be removably attached to the housing. The lid includes a pair of hinges that engage a corresponding pair of openings in the housing, and a latch that engages a ridge on the housing when the lid is in the closed position. The lid also includes a pair of contacts that extend from the lid to mate with connectors of a control unit to be powered by the batteries in the assembly. A spring is included in the housing for connecting to a positive terminal of a first battery and a negative terminal of a second battery.

Abstract: A metal-air battery is shown. The metal-air battery includes a housing holding at least one metal-air cell and an interface electrically coupled to the housing holding the at least one metal-air cell. The interface includes an air management system. The air management system includes a housing having at least one cavity and a passage to allow air flow from the cavity. The housing carries contacts to make electrical contact with the interface. A motor is disposed within the one cavity and an impeller is in communication with the motor. An electronic circuit is provided to control the motor and a cover disposed over one side of the housing. The metal-air battery can be a zinc-air battery.

Abstract: A frame device for supporting objects such as batteries during seismic stress, comprising a pair of end frame members mounted in upstanding spaced apart relation by a plurality of vertically spaced elongated channel support members secured at opposite terminal ends to the vertical columns of the end frame members, shelves for supporting batteries spanning the channel support members and defining a plurality of compartments for the batteries, each end frame member being formed of a single sheet material shaped to define vertical columns and a web extending between the end columns, a pair of anchors, means for securing the end frames to the anchors, and means defining a plurality of openings in the web of each end frame generally aligned with the compartments formed by the shelves to provide horizontal ventilation of batteries mounted in the compartments.

Abstract: A bus bar simultaneously performs electrical connection between unit cells and detection of voltage of the unit cells in a battery module having the same and includes: vertical bent parts formed by bending opposite ends of a strip-shaped bar body in the same direction, the vertical bent parts being provided with coupling grooves or protrusions; and a horizontal bent part formed by bending one of the vertical bent parts toward the bar body such that the horizontal bent part is parallel with the bar body. The electrode terminals of the unit cells are connected to the rear surface of the bar body of the bus bar, whereby the electrical connection between the unit cells is accomplished, and the horizontal bent part of the bus bar is directly connected to a battery management system for monitoring the potential difference and the temperature of the unit cells to control the unit cells.

Abstract: A battery module includes a plurality of batteries provided adjacent to one another. Each battery includes a case, which has a frame-shaped peripheral wall having open ends and a sidewall provided at one end of the peripheral wall, and a cell which is contained in the case and exposed at the other end of the peripheral wall. In two adjacent batteries of the batteries, the other end of a peripheral wall of one battery and one end of a peripheral wall of the other battery are opposed to each other.

Abstract: A cell binder includes a frame body and a frame body. A storage portion of a electric storage cell are pressed/clamped by the bottom of an accommodating portion of the frame body and the bottom of an accommodating portion of the frame body. Also, a sealing portion of the electric storage cell is accommodated in a gap between the bottom of a fitting concave portion of the frame body 16 and the front end of a projecting portion of the other frame body, in a state of being deflected by bending, and the sealing portion is clamped between an inner wall of the fitting concave portion and an outer wall of the projecting portion, thereby fitting the frame bodies to each other. This makes it possible to reduce the size for clamping the sealing portion and to achieve the downsizing of the entire package. In addition, providing the sealing portion with deflections allows movements of the electric storage cell to be accommodated when vibrations are applied.

Abstract: Disclosed are a battery pack and a method of producing the same. A battery pack includes a cell main body in which a cell element comprising a solid state electrolyte or a gel form electrolyte disposed between a cathode active material layer and an anode active material layer is contained inside a sheath material comprised of an aluminum laminated film, an outer case having a box-like shape with one end face open and containing the cell main body therein, and a cap for closing the open face of the outer case. In the battery pack, initial charging of the cell main body is conducted after the cell main body is contained into the outer case to assemble the battery pack. An enhancement of cell capacity at a fixed outside size or a reduction in outside size at a fixed cell capacity is achieved.