JP6784009B2 - Power storage element and manufacturing method of power storage element - Google Patents

Description

The present invention relates to a power storage element and a method for manufacturing the power storage element.

There is known a power storage element in which a metal terminal to which a bus bar is connected is crimped and fixed to a battery case by a rivet (see, for example, Patent Document 1).

JP-A-2009-301874

Usually, in the form of using a plurality of batteries, the terminals of the power storage elements are connected to each other via a bus bar. When a battery receives vibration or shock, the vibration or shock is transmitted to another battery via the bus bar. In the power storage element in which the metal terminals are crimped and fixed by the rivets as described above, the vibration and impact are transmitted to the rivets, and it is expected that the rivet fastening force is reduced. The decrease in the fastening force leads to a decrease in the performance of the power storage element such as an increase in resistance.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a power storage element that suppresses a decrease in fastening force due to vibration or impact via a bus bar.

In order to achieve the above object, the power storage element according to one aspect of the present invention includes a container, an external terminal arranged outside the container, and a fixing member penetrating the container and connected to a part of the external terminal. The fixing member and the external terminal are joined by a male screw formed on a part of the fixing member and a first nut that engages with the male screw. ing.

Further, in the method for manufacturing a power storage element according to one aspect of the present invention, a container, an external terminal arranged on the outside of the container, and a fixing member penetrating the container and partially formed with a male screw are provided. A method of manufacturing a power storage element to be provided, in which an external terminal is fixed by a male screw of a fixing member and a first nut engaged with the male screw, and then the inner end of the container in the fixing member is crimped.

According to the present invention, it is possible to suppress a decrease in fastening force due to vibration or impact via the bus bar.

It is a perspective view which shows typically the appearance of the power storage element which concerns on embodiment of this invention. It is a perspective view which shows each component which the power storage element has by separating the container body of the container of the power storage element which concerns on embodiment of this invention. FIG. 5 is a cross-sectional view showing a configuration in which a positive electrode terminal and a negative electrode terminal according to an embodiment of the present invention are fixed to a lid together with a positive electrode current collector and a negative electrode current collector. It is an exploded view which shows each component when the structure around the positive electrode terminal of the power storage element which concerns on embodiment of this invention is disassembled. It is sectional drawing which shows the structure which the positive electrode terminal which concerns on embodiment of this invention is fixed to the lid together with the positive electrode current collector. It is a top view which shows the schematic structure of the fixing member, a nut, a washer and a positive electrode terminal which concerns on embodiment of this invention. It is sectional drawing which shows one step of the manufacturing method of the power storage element which concerns on this embodiment. It is sectional drawing which shows one step of the manufacturing method of the power storage element which concerns on this embodiment. It is sectional drawing which shows one step of the manufacturing method of the power storage element which concerns on this embodiment.

Hereinafter, the power storage element according to the embodiment of the present invention will be described with reference to the drawings. In addition, all the embodiments described below show a preferable specific example of the present invention. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, manufacturing processes, order of manufacturing processes, etc. shown in the following embodiments are examples, and are not intended to limit the present invention. Further, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept are described as arbitrary components.

(Embodiment)
First, the configuration of the power storage element 10 will be described. FIG. 1 is a perspective view schematically showing the appearance of the power storage element 10 according to the embodiment of the present invention. FIG. 2 is a perspective view showing each component of the power storage element 10 by separating the container body 111 of the container 100 of the power storage element 10 according to the embodiment of the present invention. In these figures, the Z-axis direction is shown as the vertical direction, and the Z-axis direction may be described below as the vertical direction. However, depending on the usage mode, the Z-axis direction may not be the vertical direction. Therefore, the Z-axis direction is not limited to the vertical direction. The same applies to the following figures.

The power storage element 10 is a secondary battery capable of charging electricity and discharging electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage element 10 is not limited to the non-aqueous electrolyte secondary battery, and may be a secondary battery other than the non-aqueous electrolyte secondary battery, or may be a capacitor.

As shown in FIGS. 1 and 2, the power storage element 10 includes a container 100, a positive electrode terminal 200 and a negative electrode terminal 201, a positive electrode current collector 120 and a negative electrode current collector 130, and fixing members 300 and 301. It includes nuts 600 and 601, washers 800 and 801 and an electrode body 140.

Further, although a liquid such as an electrolytic solution (non-aqueous electrolyte) is sealed inside the container 100 of the power storage element 10, the illustration of the liquid is omitted. The type of electrolytic solution sealed in the container 100 is not particularly limited as long as it does not impair the performance of the power storage element 10, and various types can be selected.

The container 100 is composed of a container main body 111 having a rectangular tubular shape and a bottom, and a lid 110 which is a plate-shaped member that closes the opening of the container main body 111. Further, the container 100 can be sealed inside by accommodating the positive electrode current collector 120, the negative electrode current collector 130, the electrode body 140 and the like inside, and then welding the lid 110 and the container body 111 or the like. It is possible. The material of the lid 110 and the container body 111 is not particularly limited, but is preferably a weldable metal such as stainless steel, aluminum, aluminum alloy, iron, or plated steel plate.

The electrode body 140 includes a positive electrode, a negative electrode, and a separator, and is a member capable of storing electricity. The positive electrode is a positive electrode active material layer formed on a positive electrode base material foil which is a long strip-shaped metal foil made of aluminum, an aluminum alloy, or the like. Further, the negative electrode is a negative electrode active material layer formed on a negative electrode base material foil which is a long strip-shaped metal foil made of copper, a copper alloy, or the like. The separator is a microporous sheet made of resin. Here, as the positive electrode active material used for the positive electrode active material layer or the negative electrode active material used for the negative electrode active material layer, any known material is appropriately known as long as it is a positive electrode active material or a negative electrode active material capable of storing and releasing lithium ions. Can be used.

The electrode body 140 is formed by winding what is arranged in a layer so that a separator is sandwiched between the negative electrode and the positive electrode, and is electrically connected to the positive electrode current collector 120 and the negative electrode current collector 130. Has been done. Although FIG. 2 shows the electrode body 140 having an oval cross section, it may have a circular shape or an elliptical shape. Further, the shape of the electrode body 140 is not limited to the winding type, and may be a laminated type in which flat plate-shaped electrode plates are laminated.

The positive electrode terminal 200 is an external terminal that is arranged outside the container 100 and is electrically connected to the positive electrode of the electrode body 140. Further, the negative electrode terminal 201 is an external terminal arranged outside the container 100 and electrically connected to the negative electrode body 140. That is, the positive electrode terminal 200 and the negative electrode terminal 201 lead the electricity stored in the electrode body 140 to the external space of the power storage element 10, and the electricity is stored in the internal space of the power storage element 10 in order to store electricity in the electrode body 140. It is a conductive electrode terminal for introducing.

Further, the positive electrode terminal 200 and the negative electrode terminal 201 are attached to the lid 110 arranged above the electrode body 140. Specifically, the positive electrode terminal 200 is fixed to the lid 110 together with the positive electrode current collector 120 by the fixing member 300 and the first nut 600. Similarly, the negative electrode terminal 201 is fixed to the lid 110 together with the negative electrode current collector 130 by the fixing member 301 and the nut 601. The detailed configuration in which the positive electrode terminal 200 and the negative electrode terminal 201 are fixed to the lid 110 together with the positive electrode current collector 120 and the negative electrode current collector 130 will be described later.

The positive electrode current collector 120 and the negative electrode current collector 130 are arranged inside the container 100, that is, on the inner surface of the lid 110 (the surface on the minus side in the Z-axis direction). Specifically, the positive electrode current collector 120 is arranged between the positive electrode of the electrode body 140 and the side wall of the container body 111, and is electrically connected to the positive electrode terminal 200 and the positive electrode of the electrode body 140. It is a member having rigidity. The negative electrode current collector 130 is arranged between the negative electrode of the electrode body 140 and the side wall of the container body 111, and has conductivity and rigidity that are electrically connected to the negative electrode terminal 201 and the negative electrode of the electrode body 140. It is a member. The positive electrode current collector 120 is made of aluminum, an aluminum alloy, or the like, like the positive electrode base material foil of the electrode body 140. Further, the negative electrode current collector 130 is made of copper, a copper alloy, or the like, like the negative electrode base material foil of the electrode body 140.

The fixing member 300 is a member that connects and fixes the positive electrode terminal 200 and the positive electrode current collector 120. Further, the fixing member 301 is a member that connects and fixes the negative electrode terminal 201 and the negative electrode current collector 130. Specifically, the fixing member 300 fixes the positive electrode terminal 200 and the positive electrode current collector 120 to the lid 110, and the fixing member 301 fixes the negative electrode terminal 201 and the negative electrode current collector 130 to the lid 110. .. Further, the fixing members 300 and 301 are formed of a conductive member such as metal. The fixing member 300 is preferably made of aluminum or an aluminum alloy, like the positive electrode current collector 120 and the positive electrode base material foil of the electrode body 140. Further, the fixing member 301 is preferably made of copper or a copper alloy, like the negative electrode current collector 130 and the negative electrode base material foil of the electrode body 140. Further, the first nuts 600 and 601 are engaged with the outer part of the container 100 in the fixing members 300 and 301.

The first nuts 600 and 601 are made of a conductive member such as metal. The first nut 600 is preferably made of aluminum or an aluminum alloy, like the positive electrode current collector 120 and the positive electrode base material foil of the electrode body 140. Further, the nut 601 is preferably made of copper, a copper alloy, aluminum, or the like, like the negative electrode base material foil of the negative electrode current collector 130 and the electrode body 140.

The washers 800 and 801 are washers made of a conductive member such as metal. The washer 800 is preferably made of aluminum or an aluminum alloy, like the positive electrode current collector 120 and the positive electrode base material foil of the electrode body 140. Further, the washer 801 is preferably made of copper, a copper alloy, aluminum, or the like, like the negative electrode base material foil of the negative electrode current collector 130 and the electrode body 140. If the loosening prevention function is to be enhanced, elastic rings such as spring washers may be applied as the washers 800 and 801.

Next, the configuration in which the positive electrode terminal 200 and the negative electrode terminal 201 are fixed to the lid 110 together with the positive electrode current collector 120 and the negative electrode current collector 130 by the fixing members 300 and 301 and the first nuts 600 and 601 will be described. To do. First, the outline of the configuration will be described. Since the configuration on the positive electrode terminal 200 side and the configuration on the negative electrode terminal 201 side have the same configuration, the configuration on the positive electrode terminal 200 side will be mainly described below, and the configuration on the negative electrode terminal 201 side will be described. Is omitted or abbreviated.

FIG. 3 is a cross-sectional view showing a configuration in which the positive electrode terminal 200 and the negative electrode terminal 201 according to the embodiment of the present invention are fixed to the lid 110 together with the positive electrode current collector 120 and the negative electrode current collector 130. Specifically, FIG. 3 is a cross section showing the configuration around the positive electrode terminal 200 and the negative electrode terminal 201 when the power storage element 10 shown in FIG. 2 is cut along a plane parallel to the XZ plane including the line III-III. It is a figure.

As shown in FIG. 3, the power storage element 10 further includes a first sealing member 400 and a second sealing member 500 on the positive electrode terminal 200 and the positive electrode current collector 120 side. Further, the positive electrode terminal 200 has a connecting portion 210 and a terminal main body portion 220.

The positive electrode current collector 120 is an electrode which is a flat plate-shaped terminal-side arrangement portion 121 connected to the positive electrode terminal 200 via a fixing member 300 and two long legs joined to one end of the electrode body 140. It has a body connecting portion 122.

The connecting portion 210 is a member that is arranged outside the container 100 and connects the terminal main body portion 220 and the fixing member 300. That is, the connecting portion 210 is arranged above the lid 110 (plus side in the Z-axis direction), and connects the terminal body portion 220 on the positive electrode terminal 200 side and the fixing member 300. The connecting portion 210 is formed in a plate shape with a conductive member such as metal (for example, aluminum). Further, the connecting portion 210 is fixed to the lid 110 together with the terminal-side arrangement portion 121 of the positive electrode current collector 120 by the fixing member 300 and the first nut 600. The terminal body 220 can be attached with a bus bar 700 that connects the electrode terminals of the power storage element 10, and includes a bolt portion 240 and a second nut 250.

The bolt portion 240 is a bolt-shaped member protruding outward from the container 100, and the bus bar 700 can be attached to the bolt portion 240. Specifically, on the positive electrode terminal 200 side, the bus bar 700 is attached to the bolt portion 240 by inserting the bolt portion 240 into the through hole 710 having a circular shape in the top view provided in the bus bar 700. The bolt portion 240 is formed of a conductive member such as metal (for example, aluminum or stainless steel).

The second nut 250 is a nut-shaped member that engages with the bolt portion 240. Specifically, on the positive electrode terminal 200 side, the second nut 250 is screwed and fastened to the bolt portion 240 to which the bus bar 700 is attached to fix the bus bar 700. In this way, the bus bar 700 can be fixed by the bolt portion 240 and the second nut 250. The second nut 250 is made of a conductive member such as metal (for example, aluminum or stainless steel). A washer may be attached to the bolt portion 240 so as to be arranged between the second nut 250 and the bus bar 700.

The first sealing member 400 is a packing in which at least a part thereof is arranged between the positive electrode terminal 200 and the lid 110. The first sealing member 400 is preferably made of an insulating member having a lower rigidity than the lid 110. For example, the first sealing member 400 is made of a resin such as polyphenylene sulfide (PPS) or polypropylene (PP).

The second sealing member 500 is a packing in which at least a part thereof is arranged between the terminal side arrangement portion 121 of the positive electrode current collector 120 and the lid body 110. The second sealing member 500 is preferably made of an insulating member having a lower rigidity than the lid 110. The second sealing member 500 is made of, for example, a resin such as polyphenylene sulfide (PPS) or polypropylene (PP).

Next, the details of the configuration in which the positive electrode terminal 200 and the negative electrode terminal 201 are fixed to the lid 110 together with the positive electrode current collector 120 and the negative electrode current collector 130 by the fixing members 300 and 301 and the first nuts 600 and 601. ,explain. Since the configuration on the positive electrode terminal 200 side and the configuration on the negative electrode terminal 201 side have the same configuration, the configuration on the positive electrode terminal 200 side will be mainly described below, and the configuration on the negative electrode terminal 201 side will be described. Is omitted or abbreviated.

First, the details of each component before fixing the positive electrode terminal 200 and the positive electrode current collector 120 to the lid 110 will be described. FIG. 4 is an exploded view showing each component when the configuration around the positive electrode terminal 200 of the power storage element 10 according to the embodiment of the present invention is disassembled. Specifically, FIG. 4 is a cross-sectional view (a view of each component before assembly) when each component around the positive electrode terminal 200 shown in FIG. 3 is separated.

As shown in FIG. 4, the connecting portion 210 of the positive electrode terminal 200 is a rectangular and flat plate-shaped member, and the first opening 211 and the second opening 212 are formed. The first opening 211 is a top-view circular through hole into which the screw body 311 of the fixing member 300 described later is inserted, and the second opening 212 is the upper surface into which the bolt portion 240 of the terminal body 220 is inserted. It is a through hole in the shape of a visual circle. The shapes of the first opening 211 and the second opening 212 may be any shape corresponding to the outer shapes of the screw body 311 and the bolt portion 240, for example, an elliptical or rectangular through hole when viewed from the upper surface. Alternatively, it may be a notch cut out in a semicircular shape or a rectangular shape.

The bolt portion 240 of the terminal main body portion 220 has a male screw 221 and a head portion 222. The male screw 221 is a cylindrical portion protruding upward (plus side in the Z-axis direction) from the head 222, and a screw thread is formed on the outer periphery thereof. The head 222 is formed in a flat shape, for example, an octagonal column. The connecting portion 210 and the terminal main body portion 220 may be integrally formed. Further, the positive electrode terminal 200 may have a configuration in which only the connecting portion 210 is provided without having the terminal main body portion 220. In this case, the second opening 212 is not formed in the connecting portion 210, and the positive electrode terminal 200 is joined to the bus bar 700 connecting the electrode terminals of the power storage element 10 by welding.

The upper part (plus side in the Z-axis direction) of the fixing member 300 is a screw body, and the lower part (minus side in the Z-axis direction) is a hollow rivet. Specifically, the fixing member 300 has, for example, an octagonal column-shaped flange portion 320 that projects outward in the central portion in the Z-axis direction. The portion of the fixing member 300 above the flange portion 320 is a screw body 311 made of a male screw. Specifically, the screw body 311 is a cylindrical portion, and a thread is formed on the outer periphery thereof. On the other hand, the portion of the fixing member 300 below the flange portion 320 is the hollow rivet portion 312. The rivet portion 312 is formed in a hollow cylindrical shape.

The screw body 311 of the fixing member 300 is inserted into the first opening 211, and the rivet portion 312 collects electricity from the tubular opening 421, the lid opening 112, the second sealing member opening 510, which will be described later. It is inserted into the body opening 123.

The first sealing member 400 is a rectangular and flat member, and has a flat plate-shaped portion 410 and a cylindrical tubular portion 420 projecting downward (minus side in the Z-axis direction) from the plate-shaped portion 410. And have. Here, the plate-shaped portion 410 is formed with a first plate-shaped portion recess 411 and a second plate-shaped portion recess 412. The flange portion 320 of the fixing member 300 is inserted and fitted into the first plate-shaped portion recess 411. The head 222 of the terminal body 220 is inserted and fitted into the second plate-shaped recess 412. Further, the first plate-shaped recess 411 and the second plate-shaped recess 412 are octagonal recesses when viewed from above. The shapes of the first plate-shaped recess 411 and the second plate-shaped recess 412 may be any shape corresponding to the outer shapes of the flange portion 320 and the head 222, and are not limited to the octagonal shape. Further, the tubular portion 420 is formed with a tubular portion opening 421 which is a through hole having a circular shape when viewed from above. The rivet portion 312 of the fixing member 300 is inserted into the tubular portion opening 421.

The lid body 110 is a rectangular and flat plate-shaped member, and the lid body opening 112 is formed. The tubular portion 420 of the first sealing member 400 is inserted into the lid opening 112, which is a through hole having a circular shape when viewed from above.

The second sealing member 500 is a rectangular and flat plate-shaped member, and has a second sealing member opening 510 and a second sealing member recess 520, which are through holes having a circular shape when viewed from above. The tubular portion 420 of the first sealing member 400 is inserted into the second sealing member opening 510. In the second sealing member recess 520, the terminal-side arrangement portion 121 of the positive electrode current collector 120 is arranged inward.

In the positive electrode current collector 120, a current collector opening 123 is formed in the terminal side arrangement portion 121. The rivet portion 312 of the fixing member 300 is inserted into the current collector opening 123. The current collector opening 123 is a through hole having a circular shape when viewed from above. The shape of the current collector opening 123 may be any shape corresponding to the outer shape of the screw body 311. For example, it may be cut into an elliptical or rectangular through hole, or a semicircular or rectangular shape when viewed from above. It does not matter if it is a notch or the like.

Next, the configuration after fixing the positive electrode terminal 200 and the positive electrode current collector 120 to the lid 110 will be described. FIG. 5 is a cross-sectional view showing a configuration in which the positive electrode terminal 200 according to the embodiment of the present invention is fixed to the lid 110 together with the positive electrode current collector 120. Specifically, FIG. 5 is an enlarged cross-sectional view showing an enlarged configuration around the positive electrode terminal 200 shown in FIG.

The screw body 311 of the fixing member 300 is arranged so as to penetrate the connecting portion 210. Then, the washer 800 and the first nut 600 are attached to the screw body 311 and the first nut 600 is fastened to the screw body 311. By this fastening, the flange portion 320 and the first nut 600 sandwich and tighten the connecting portion 210 in the Z-axis direction. As a result, the fixing member 300 is fixed to the connecting portion 210.

The rivet portion 312 of the fixing member 300 is arranged so as to penetrate the lid 110, the first sealing member 400, the second sealing member 500, and the terminal-side arrangement portion 121 of the positive electrode current collector 120. .. The rivet portion 312 is crimped after penetrating these members. As a result, the end portion of the rivet portion 312 located inside the container 100 is crimped. Specifically, the wall portion forming the end portion of the rivet portion 312 is pressed so as to spread outward, and the exposed main surface of the terminal side arrangement portion 121 (the main surface opposite to the second sealing member 500). ). This close contact portion is referred to as a close contact portion 313. The close contact portion 313 is formed in an annular shape centered on the axial center of the fixing member 300 when viewed from the axial direction (Z-axis direction) of the rivet portion 312. Since the close contact portion 313 is in close contact with the exposed main surface of the terminal side arrangement portion 121 over the entire circumference, the airtightness between the close contact portion 313 and the terminal side arrangement portion 121 is enhanced. Further, by this caulking, the flange portion 320 and the close contact portion 313 form the first sealing member 400, the lid 110, the second sealing member 500, and the terminal side arrangement portion 121 of the positive electrode current collector 120. Tighten by sandwiching in the Z-axis direction. As a result, the first sealing member 400, the lid 110, the second sealing member 500, and the terminal-side arrangement portion 121 of the positive electrode current collector 120 are fixed to the fixing member 300.

As described above, by fastening with the first nut 600 and fastening with the close contact portion 313, the connecting portion 210, the first sealing member 400, the lid 110, and the second sealing are attached to the fixing member 300. The member 500 and the terminal-side arrangement portion 121 of the positive electrode current collector 120 are fixed. In other words, with respect to the lid 110 forming the container 100, the connecting portion 210, the first sealing member 400, the fixing member 300, the second sealing member 500, and the terminal-side arrangement portion of the positive electrode current collector 120. 121 and is fixed.

Here, the degree of increase in contact resistance between the power storage element 10 according to the present embodiment and the comparative example in which the first nut 600 and the washer 800 are not used is compared.

In the power storage element 10 according to the present embodiment, the washer 800 is attached to the screw body 311 of the fixing member 300 to fasten the first nut 600, but in the comparative example, the portion is fastened by caulking. different. That is, in the comparative example, both ends of the fixing member are crimped. Other parts of the comparative example are the same as the power storage element 10 according to the present embodiment.

A force (see arrow Y in FIG. 5) was applied to the bus bar 700 so as to reciprocate the tips of the bus bars 700 of the power storage element 10 and the comparative example in the Z-axis direction. The table below shows the resistance value for every 10 times of addition.

In the first embodiment, the resistance value does not fluctuate significantly even if the number of additions increases from 0 to 50. However, in the comparative example, the resistance value increases from the point where the number of additions exceeds 30 times, and increases significantly after 40 times. It can be considered that this is because the bus bar 700 swings and the axial force acts on the crimped portion of the fixing member of the comparative example, so that the bus bar 700 loosens and the resistance value increases. On the other hand, in the power storage element 10 according to the first embodiment, it can be considered that the loosening of the first nut 600 is suppressed and the resistance value does not fluctuate significantly. As shown in the above comparison, by joining the positive electrode terminal 200 and the fixing member 300 with the first nut 600, the positive electrode terminal 200 is loosened due to the vibration transmitted from the bus bar 700, and the resistance value is increased due to the loosening. I was able to suppress it.

Here, since the washer 800 is provided between the connecting portion 210 and the first nut 600, the loosening prevention function of the washer 800 can more efficiently suppress the loosening of the first nut 600. Therefore, it is possible to suppress an increase in contact resistance due to loosening of the first nut 600.

Further, since the end portion of the rivet portion 312 located inside the lid body 110 is crimped, the portion (adhesion portion 313) formed by this caulking is the inner member of the lid body 110 (the present embodiment). Then, it comes into close contact with the terminal side arrangement portion 121). Therefore, the airtightness between the member and the rivet portion 312 can be improved. Further, since the first sealing member 400 and the second sealing member 500 are pressed by the tightening by the close contact portion 313, the airtightness between the first sealing member 400 and the second sealing member 500 is further improved. Can be made to.

FIG. 6 is a top view showing a schematic configuration of the fixing member 300, the first nut 600, the washer 800, and the positive electrode terminal 200 according to the embodiment of the present invention. As shown in FIG. 6, a linear mark M1 along the radial direction is provided on the main surface 600a of the first nut 600 facing outward. Further, a mark M2 is provided on the main surface 210a of the positive electrode terminal 200 facing outward of the connecting portion 210. The mark M2 is arranged at a position where the first nut 600 engages with the screw body 311 and is aligned with the mark M1 when tightened. Specifically, the mark M2 is provided in a straight line so as to overlap the extension line of the mark M1 after the first nut 600 is fastened. When the relative positional deviations of the marks M1 and M2 can be visually recognized, the user can recognize a decrease in the fastening force of the first nut 600 with respect to the screw body 311.

Further, since the bus bar 700 can be fixed by the bolt portion 240 and the second nut 250, the bus bar 700 can be fixed more easily than in the case of fixing by welding, and the bus bar 700 can be removed. As a result, the power storage element 10 can be easily replaced. Further, by setting the direction in which the second nut 250 is fastened and the direction in which the first nut 600 is fastened to be the same direction (minus side in the Z-axis direction), the first nut 600 is lifted when the second nut 250 is fastened. The force to try does not act on the first nut 600. Therefore, it is possible to prevent the first nut 600 from loosening when the bus bar 700 is fixed.

Next, a method of manufacturing the power storage element 10 will be described. 7, 8 and 9 are cross-sectional views showing one step of the manufacturing method of the power storage element 10 according to the present embodiment. Specifically, FIGS. 7, 8 and 9 are diagrams corresponding to FIG.

First, as shown in FIG. 7, with respect to the lid 110, the connecting portion 210, the terminal body portion 220, the first sealing member 400, the fixing member 300, the second sealing member 500, and the positive electrode collection. Assemble the terminal side arrangement portion 121 of the electric body 120.

After that, as shown in FIG. 8, the operator attaches the washer 800 to the screw body 311 and then attaches and tightens the first nut 600. By this fastening, the fixing member 300 is fixed to the connecting portion 210. After fastening, the operator forms the mark M1 on the main surface 600a of the first nut 600, and forms the mark M2 on the main surface 210a of the connecting portion 210. If the position of the first nut 600 after fastening is known in advance, the marks M1 and M2 may be formed in advance at predetermined positions of the first nut 600 and the connecting portion 210 before fastening.

Next, as shown in FIG. 9, the operator crimps the end portion of the rivet portion 312 located inside the container 100 to form the close contact portion 313. By this caulking, the first sealing member 400, the lid 110, the second sealing member 500, and the terminal-side arrangement portion 121 of the positive electrode current collector 120 are fixed to the fixing member 300. As a result, with respect to the lid 110, the connecting portion 210, the terminal main body portion 220, the first sealing member 400, the fixing member 300, the second sealing member 500, and the terminal side of the positive electrode current collector 120. The arrangement portion 121 and the arrangement portion 121 are fixed.

When the first nut 600 is tightened to the screw body 311 after crimping the end portion of the rivet portion 312 of the fixing member 300, the force for fastening the first nut 600 acts on the close contact portion 313, and the close contact portion 313. There is a risk of weakening the fastening by 313. However, as described above, if the end portion of the fixing member 300 at the rivet portion 312 is crimped after the first nut 600 is tightened to the screw body 311 to prevent loosening of the fastening by the close contact portion 313. it can.

Although the power storage element according to the embodiment of the present invention and its modified example has been described above, the present invention is not limited to the above-described embodiment and its modified example. That is, it should be considered that the embodiments disclosed this time and examples thereof are examples in all respects and are not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended that all modifications within the meaning and scope equivalent to the scope of claims are included.

For example, in the above-described embodiment and its modification, the rivet portion 312 of the fixing member 300 is a hollow rivet, but it may be a solid rivet.

Further, in the above-described embodiment and its modification, the power storage element 10 is provided with one electrode body 140, but a configuration including a plurality of electrode bodies may be used.

In addition, a form constructed by arbitrarily combining the above-described embodiment and the above-mentioned modification is also included in the scope of the present invention.

The present invention can provide a power storage element capable of easily determining a decrease in fastening force applied to a terminal.

10 Power storage element 100 Container 110 Lid 111 Container body 112 Lid opening 120 Positive electrode current collector 121 Terminal side arrangement 122 Electrode connection 123 Current collector opening 130 Negative current collector 140 Electrode 200 Positive terminal (external) Terminal)
201 Negative electrode terminal (external terminal)
210 Connecting part 211 First opening 212 Second opening 220 Terminal body part 221 Male screw 222 Head 231 Narrow part 232 Widening part 240 Bolt part 250 Second nut 300, 301 Fixing member 311 Screw body (male screw)
312 Rivet part 313 Adhesion part 320, 320A Flange part 400 First sealing member 410 Plate-shaped part 411 First plate-shaped part recess 412 Second plate-shaped part recess 420 Cylindrical part 421 Cylindrical part opening 500 Second sealing Member 510 Second sealing member Opening 520 Second sealing member Recess 600,601 First nut 600a Main surface 700 Busbar 710 Through hole 800,801 Washer M1, M2 Mark

Claims (5)

A container with a lid that extends in a predetermined direction ,
An external terminal located on the outside of the container and
A fixing member that penetrates the container and is connected to a part of the external terminal is provided.
The external terminal has a terminal body portion to which a bus bar is attached and a connecting portion connected to the terminal body portion.
The connecting portion, said male threads formed on a portion of the fixing member is inserted, by the male screw and the male screw and the first nut to engage, directly bonded portions with said fixing member Have and
The terminal body portion is arranged on the side of the fixing member in a direction from the center portion to the end portion of the lid body in the predetermined direction with respect to the joint portion joined to the portion of the fixing member , and the terminal body portion is used as described. The bus bar is connected to the bus bar so as to extend in the predetermined direction.
The fixing member has the inner end of the container crimped and is in close contact with the inner member of the container .
Power storage element. A washer is provided between the external terminal and the first nut.
The power storage element according to claim 1. At least one of the external terminal, the part of the fixing member, and the first nut is provided with a mark indicating a misalignment of the first nut.
The power storage element according to claim 1 or 2. The terminal body portion has a second nut which engages the bolt portion and the bolt portion, wherein the bus bar is fixed by the bolt portion and the second nut,
The power storage element according to any one of claims 1 to 3. With the container
An external terminal located on the outside of the container and
A method for manufacturing a power storage element, comprising a fixing member that penetrates the container and has a male screw partially formed therein.
After the external terminal is directly fixed to the fixing member by the male screw of the fixing member inserted into a part of the external terminal and the first nut engaged with the male screw, the external terminal is directly fixed to the fixing member .
The inner end of said container in said fixing member by caulking, Ru is adhered to the inner member of the container,
Manufacturing method of power storage element.

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