JP2015022941A - Power storage element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage element in which sealability can be enhanced in the vicinity of the electrode terminal thereof, and the sealability can be maintained.SOLUTION: In a power storage element 100 including a container 110, an electrode body 200 to be housed in the container, an electrode terminal 130, a collector member 160 for electrically connecting the electrode terminal and electrode body, and an external insulation sealant 120 for insulating the container and the electrode terminal, the electrode terminal has a columnar connection part 132 penetrating the container and being connected with the collector member, and a planar terminal body 131, i.e., the end of the connection part, arranged on the outside of the container. The external insulation sealant insulates the container and electrode terminal by being arranged between the container and connection part and between the container and terminal body. At least one of the terminal body and container is formed so that a first interval d1 between the terminal body and container at a first position P1 of the terminal body is smaller than a second interval d2 between the terminal body and container at a second position P2 closer to the connection part than the first position.

Description

  The present invention relates to power storage elements such as secondary batteries and other batteries.

  Secondary batteries are widely used as power sources for electronic devices such as mobile phones and IT devices, as well as for replacing primary batteries. In particular, since non-aqueous electrolyte secondary batteries represented by lithium ion batteries have high energy density, they are also being applied to industrial large electric devices such as electric vehicles.

  Conventionally, in a non-aqueous electrolytic secondary battery, in order to take out the electric power generated by the electrode body disposed inside the container, the current collector is electrically connected to the positive electrode and the negative electrode of the electrode body and disposed inside the container. There is a connecting portion for connecting the member and an electrode terminal outside the container. The connecting portion is integrally formed with the electrode terminal, and penetrates the lid portion of the container in order to connect the current collecting member inside the container and the electrode terminal outside the container. For this reason, the cover part is provided with a through hole through which the connection part passes.

  The container is often made of metal, and if the connection part penetrates the container without insulation, it is short-circuited by the container, so the part where the through hole of the container is formed, the electrode terminal, and the connection part And the current collecting member must be insulated. In addition, the container contains the electrolytic solution together with the electrode body, and it is necessary to prevent the electrolytic solution from leaking from the through hole to the outside of the container.

  In the conventional power storage element, as in Patent Document 1, for example, in order to insulate the container from the electrode terminal, the connection portion, and the current collecting member, and to prevent the electrolyte from leaking from the through hole of the container, An insulating sealing material is provided over the outer side and the inner side of the container at a portion where the through hole is formed. With the insulating sealing material covering the part where the through-hole of the container is formed over the inside and outside of the container, the electrode terminal outside the container and the current collecting member inside the container are pressure-bonded by the connecting portion, so that the electrode The insulation between the terminal, the connecting portion, and the current collecting member and the container and the seal are made compatible.

JP 2010-097822 A

  However, there is a high possibility that a sufficient seal cannot be maintained in the following cases. Generally, the longer the time elapses when the insulating member is compressed at a temperature higher than room temperature (for example, 25 ° C.) (for example, 80 ° C.), the more the seal by the insulating member cannot be maintained.

  Accordingly, the present invention has been made in view of such a situation, and provides a power storage element that can improve the sealing performance in the vicinity of the electrode terminal of the power storage element and can maintain the sealing performance. For the purpose.

  To achieve the above object, a container, an electrode body housed in the container, an electrode terminal, a current collecting member for electrically connecting the electrode terminal and the electrode body, the container and the electrode A storage element including an insulating member that insulates the terminal, wherein the electrode terminal penetrates the container and is connected to the current collecting member at a columnar connection portion and an end portion of the connection portion And having a plate-like terminal main body disposed outside the container, and the insulating member is disposed between the container, the connection portion and the terminal main body, whereby the container and the The terminal body is insulated from at least one of the terminal body and the container from the second position of the terminal body toward the first position farther from the connecting portion than the second position. So that the distance from the container is small It has been made.

  According to this, the space | interval of the terminal main body and container in the 1st position which is a position far from the connection part of an electrode terminal is narrow. The insulating member is sandwiched between the terminal body and the container and receives a pressing force from both. For this reason, even if an insulating member thermally expands in a high temperature environment, it can suppress that an insulating member expands toward the direction which cross | intersects the direction of a pressing force. Thereby, even if the insulating member is thermally expanded, the insulating member can be kept within a predetermined range, so that the sealing performance in the vicinity of the electrode terminal can be sufficiently maintained. Further, at least one of the terminal main body and the container is formed so that the distance between the terminal main body and the container decreases as the distance from the connection portion increases between the first position and the second position. During the thermal expansion of the insulating member, when the insulating member expands in the direction intersecting the direction of the pressing force, the force applied to the insulating member between the first position and the second position can be dispersed. . Note that this force is specifically a force that prevents the insulating member from expanding in a direction farther from the connection portion, and is a force directed in a direction closer to the connection portion. Thereby, compared with the structure of the structure where the space | interval between a terminal main body and a container becomes small rapidly, it can prevent that force is largely applied to the specific part of a terminal main body, a container, or an insulation member, and a terminal It is possible to prevent the main body, the container, or the insulating member from being damaged.

  Further, at least one of the terminal main body and the container may have a first distance between the terminal main body and the container at the first position smaller than ½ of a second distance at the second position.

  According to this, since the first interval is smaller than ½ of the second interval, even if the insulating member thermally expands in a high temperature environment, the insulating member expands in a direction intersecting the direction of the pressing force. This can be suppressed more reliably.

  A container; an electrode body housed in the container; an electrode terminal; a current collecting member that electrically connects the electrode terminal and the electrode body; and an insulation that insulates the container from the electrode terminal. A storage element including a member, wherein the electrode terminal penetrates the container and is connected to the current collecting member, and is an end of the connection part and outside the container A plate-like terminal body disposed on the container, and the insulating member is disposed between the container, the connection portion, and the terminal body to insulate the container from the electrode terminal. And at least one of the terminal main body and the container has the terminal at a second position where the first distance between the terminal main body and the container at the first position of the terminal main body is closer to the connecting portion than the first position. 1/2 of the second distance between the main body and the container It may be formed so as also small.

  According to this, the shape of at least one of the terminal body and the container is such that the first distance between the terminal body and the container at the first position is a distance between the terminal body and the container at the second position closer to the connecting portion than the first position. Less than 1/2 of the second interval. The insulating member is sandwiched between the terminal body and the container and receives a pressing force from both. That is, in the space in which the insulating member is arranged, the distance between the terminal body and the container at the first position, which is a position far from the electrode terminal connection portion, is narrow in the direction intersecting the direction of the pressing force. . For this reason, even if the insulating member thermally expands in a high temperature environment, it is possible to reliably suppress the insulating member from expanding toward the direction intersecting the direction of the pressing force. Thereby, even if the insulating member is thermally expanded, the insulating member can be kept within a predetermined range, so that the sealing performance in the vicinity of the electrode terminal can be sufficiently maintained.

  In addition, at least one of the terminal main body and the container has at least a distance between a portion of the terminal main body farthest from the connection portion and the container, and a portion of the terminal main body closest to the connection portion and the container. You may form so that it may become smaller than a space | interval.

  According to this, the distance between the terminal body and the container at the portion farthest from the connection portion of the terminal body is smaller than the distance between the terminal body and the container at the portion closest to the connection portion of the terminal body. The expansion of the insulating member can be suppressed with respect to the entire insulating member. Thereby, since the expansion | swelling of more insulating members can be suppressed, the sealing performance of an electrode terminal vicinity can be maintained more fully.

  In addition, at least one of the terminal main body and the container has a container-side surface of the terminal main body between the first position and the second position, with respect to the terminal main body-side surface of the container. It may be inclined linearly.

  According to this, the container side surface of the terminal body is inclined linearly with respect to the terminal body side surface of the container. For this reason, at the time of thermal expansion of the insulating member, when the insulating member expands in the direction intersecting the direction of the pressing force, the insulating member between the first position and the second position is close to the connection portion. The force directed in the direction can be evenly distributed at least between the first position and the second position. Thus, since the force applied to the terminal body, the container, or the insulating member can be made uniform between the first position and the second position, the force applied at each position can be minimized. For this reason, it can prevent more effectively that a terminal main part, a container, or an insulating member is damaged.

  In addition, at least one of the terminal body and the container has a stepwise difference between the first interval in the first region including the first position and the second interval in the second region including the second position. Also good.

  According to this, the shape of at least one of the terminal main body and the container is formed such that the first interval in the first region and the second interval in the second region are stepwise different. For this reason, in at least one of the terminal body and the container, a shape in which the first interval is narrow can be easily manufactured.

  In addition, the container has a third distance between the connection portion and the container at a third position of the container at a portion facing the connection portion, the third distance between the container and the third position. You may form so that it may become smaller than the 4th space | interval of the said connection part and the said container in four positions.

  According to this, the shape of the container is such that the third distance between the connection portion and the container at the third position is the fourth distance between the connection portion and the container at the fourth position on the outer side of the container with respect to the third position. Smaller than. The insulating member is sandwiched between the connecting portion and the container, and when thermally expanded, the insulating member tends to expand in all directions. At this time, since the third interval at the third position, which is the position on the inner side of the container, is narrower than the fourth interval, the insulating member expands toward the inner side of the container even if the insulating member thermally expands. Can be suppressed. Thereby, when the insulating member is thermally expanded, the insulating member can be kept within a predetermined range even in the axial direction of the connecting portion, and thus the sealing performance in the vicinity of the electrode terminal can be sufficiently maintained.

  In addition, the container may be formed so that a distance between the connection portion and the container becomes smaller from the fourth position toward the third position.

  According to this, the container is formed so that the distance between the connecting portion and the container decreases as the distance from the terminal body increases between the third position and the fourth position. For this reason, during the thermal expansion of the insulating member, when the insulating member expands in the direction intersecting the direction of the pressing force, the force applied to the insulating member between the third position and the fourth position is dispersed. be able to. Specifically, this force is a force that prevents the insulating member from expanding toward the inside of the container, and is a force that is directed toward the terminal body. Thereby, compared with the structure of the structure where the space | interval between a connection part and a container becomes small rapidly, it can prevent that force is largely applied to the specific site | part of a terminal main body, a container, or an insulating member, and a terminal It is possible to prevent the main body, the container, or the insulating member from being damaged.

  In addition, even if the surface of the container that faces the connection portion of the container is inclined linearly with respect to the surface of the connection portion between the third position and the fourth position. Good.

  According to this, the connection part side surface of the container is inclined linearly with respect to the surface of the connection part. For this reason, at the time of thermal expansion of the insulating member, when the insulating member expands in the direction intersecting the direction of the pressing force, the insulating member between the third position and the fourth position is close to the connecting portion. The directionally directed force can be equalized at least between the third position and the fourth position. Thus, since the force applied to the terminal body, the container, or the insulating member can be made uniform between the third position and the fourth position, the force applied at each position can be minimized. For this reason, it can prevent that a terminal body, a container, or an insulating member breaks.

  Further, the electrode terminal may be sealed with the insulating member between a portion where the through hole of the container is formed and the terminal body by pressure-bonding the insulating member and the container.

  According to this, the insulating member and the container are pressure-bonded by the electrode terminal, whereby the portion where the through hole of the container is formed and the terminal body are sealed with the insulating member. For this reason, the insulating member is in a state in which a pressing force is always applied between the terminal body and the container by the electrode terminal. Even in such an insulating member that is always subjected to a pressing force and is likely to expand in a direction that intersects the pressing force when thermally expanded, the space in the direction intersecting the pressing force is narrowed. Therefore, the expansion of the insulating member in the direction can be suppressed.

  According to the electricity storage device of the present invention, the sealing performance in the vicinity of the electrode terminal of the electricity storage device can be improved, and the sealing performance can be maintained.

It is a perspective view which shows the external appearance of the nonaqueous electrolyte secondary battery which concerns on embodiment of this invention. It is a disassembled perspective view which shows the typical structure of a nonaqueous electrolyte secondary battery. It is the enlarged view to which the electrode terminal periphery was expanded among the III-III sectional drawings of the nonaqueous electrolyte secondary battery of FIG. In modification (1), it is the enlarged view to which the electrode terminal periphery was expanded among the III-III sectional drawings of the nonaqueous electrolyte secondary battery of FIG. In modification (2), it is the enlarged view to which the electrode terminal periphery was expanded among the III-III sectional drawings of the nonaqueous electrolyte secondary battery of FIG. In modification (3), it is the enlarged view to which the electrode terminal periphery was expanded among the III-III sectional drawings of the nonaqueous electrolyte secondary battery of FIG. It is a figure for demonstrating the phenomenon which generate | occur | produces when the temperature resembles a high temperature from room temperature. It is a graph which shows the result of having experimented about the residual compressibility after heating at 80 degreeC in the state which applied the predetermined pressure to three types of PPS materials, and leaving it to stand for the predetermined time.

(Knowledge that became the basis of the present invention)
The present inventor has found that the following problems occur with respect to the electricity storage device described in the “Background Art” column.

  As the insulating member is compressed at a temperature higher than room temperature (for example, 25 ° C.) (eg, 80 ° C.), the longer the time elapses, the more the sealing by the insulating member cannot be maintained. This mechanism will be described with reference to FIGS.

  FIG. 7 is a diagram for explaining a phenomenon that occurs when the temperature changes from room temperature to a high temperature.

  For example, as shown in FIG. 7A, similarly to the insulating member in the power storage element, a predetermined material is obtained by sandwiching between two plate-like members 510 in a PPS (Polyphenylene sulfide) material 500 that is a material constituting the insulating member. Apply pressure. At this time, the regulating member 520 is sandwiched between the two plate-like members 510 so that the interval between the two plate-like members 510 is maintained at the predetermined interval d10. That is, the PPS material 500 is a material whose width is larger than the predetermined interval d10 in a state before a predetermined pressure is applied. Next, as shown in FIG. 7B, the temperature is set to 80 ° C., which is a high temperature. In this case, since the PPS material 500 is compressed from the vertical direction, it thermally expands in the horizontal direction intersecting the vertical direction. And when it cools to room temperature like FIG.7 (c), the PPS material 500 shrink | contracts not only in the left-right direction but the up-down direction. As a result, the seal with the PPS material 500 cannot be maintained.

  FIG. 8 is a graph showing the results of experiments on the residual compression ratio after heating at 80 ° C. with a predetermined pressure applied to three types of PPS materials and leaving them for a predetermined time. The “residual compression ratio” here refers to the width of the PPS material in the compression direction when the room temperature (25 ° C.) and the predetermined pressure are 0 after a predetermined time (hereinafter referred to as “width after a predetermined time”). This is a value obtained by dividing the difference obtained by subtracting the width of the PPS in the compression direction (hereinafter referred to as “initial width”) immediately after applying a predetermined pressure by the width after a predetermined time. In other words, as the residual compression ratio approaches 0, the pressing force from the PPS material decreases, and when the residual compression ratio becomes negative, the seal is not completely sealed.

  As shown in FIG. 8, the material A and the material B have a residual compression rate approaching 0, and a sufficient seal cannot be maintained. Moreover, in the material C, the residual compression rate is a negative value and is not completely sealed.

  Due to such a mechanism, it is difficult for the technique of Patent Document 1 to maintain a seal in the vicinity of the electrode terminal, particularly when used in a high temperature environment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept of the present invention are described as optional constituent elements that constitute a more preferable embodiment.

(Embodiment)
FIG. 1 is a perspective view showing an external appearance of a nonaqueous electrolyte secondary battery according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing a schematic configuration of the nonaqueous electrolyte secondary battery.

  As shown in FIG. 1, the power storage device 100 of the present embodiment electrically connects a container 110, an electrode body 170 accommodated in the container 110, an electrode terminal 130, and the electrode terminal 130 and the electrode body 170. A current collecting member 160 to be connected, an external insulating sealing material 120 for insulating the container 110 and the electrode terminal 130, and an internal insulating sealing material 150 for insulating the container 110 and the current collecting member 160 are provided.

  The container 110 includes a lid part 111 and a container main body 112. The lid portion 111 is a long plate-like member that is long in the Y-axis direction (described later). The container body 112 is a member having an opening 114 at one end of a rectangular cylindrical member and a bottom at the other end. In the present embodiment, the arrangement direction of the container body 112 and the lid portion 111 is the vertical direction (Z-axis direction in FIG. 1), and the arrangement direction of the positive electrode terminal and the negative electrode terminal is the left-right direction (Y-axis in FIG. 1). Direction), and a direction perpendicular to the up-down direction and the left-right direction is defined as the front-rear direction (X-axis direction in FIG. 1).

  The lid portion 111 is formed with through holes 113 penetrating the electrode terminals 130 at both ends in the longitudinal direction. In FIG. 1, only the through hole 113 on the positive electrode side is shown, and the through hole on the negative electrode side is not shown because it is hidden behind an insulating sealing material described later.

  The electrode body 170 is formed by being wound into a long cylindrical shape while being laminated so that a separator is sandwiched between a positive electrode and a negative electrode which are band-shaped electrodes. The electrode body 170 is housed in the container 110 in such an orientation that the winding axis direction coincides with the Y-axis direction and the long axis of the cross-sectional oval shape coincides with the Z-axis direction. The positive electrode and the negative electrode are wound in a long cylindrical shape around the winding axis while being displaced from each other in the winding axis direction. The electrode body 170 has projecting portions 171 and 172 that project from the separator toward the outside in the winding axis direction (Y-axis direction) of the electrode body 170 with a predetermined width at both ends thereof. That is, the electrode body 170 has a positive-side protruding portion 171 in which the positive electrode protrudes from the separator at one end in the winding axis direction, and a negative-side protruding portion 172 in which the negative electrode protrudes from the separator at the other end. Further, the positive electrode-side protruding portion 171 and the negative electrode-side protruding portion 172 are not formed with an active material, and the metal foil as the base material is exposed. In other words, the protruding portion 171 on the positive electrode side exposes an aluminum foil that is a positive electrode base material on which the positive electrode active material layer is not formed, and the protruding portion 172 on the negative electrode side has a negative electrode on which the negative electrode active material layer is not formed. The copper foil which is a base material is exposed. A positive electrode side current collecting member 160 and a negative electrode side current collecting member 164 are electrically connected to the positive electrode side protruding portion 171 and the negative electrode side protruding portion 172, respectively.

  The upper end portion of the current collecting member 160 has a plate-like configuration (a plate portion 161 described later) parallel to the upper surface of the electrode body 170 (that is, parallel to the XY plane). A through hole 162 is formed in the configuration. Further, the current collecting member 160 has a configuration (an arm portion 163 to be described later) that is connected and fixed by ultrasonic welding or the like at the positive-side protruding portion 171 that is one end of the electrode body 170 in the winding axis direction. The negative electrode side current collecting member 164 has the same configuration and is formed of copper or a copper alloy. Since the positive current collecting member 160 and the negative current collecting member 164 have the same configuration, only the positive current collecting member 160 will be described below, and the description of the negative current collecting member 164 will be omitted. .

  The internal insulating sealing material 150 is an insulating member that insulates the container 110 and the current collecting member 160 by being disposed between the lid portion 111 and the current collecting member 160. That is, the internal insulating sealing material 150 is an insulating member that is disposed inside the container 110 and insulates the container 110 from the electrode body 170 that is electrically connected via the current collecting member 160. Further, the internal insulating sealing material 150 is pressed together with the electrode terminal 130 and the external insulating sealing material 120 to the through hole 113 formed in the lid portion 111 of the container 110, thereby sealing the through hole 113. It also functions as a sealing material (packing). The internal insulating sealing material 150 is made of synthetic resin or the like and has insulating properties and elasticity. The internal insulating sealing material 150 is formed with a through hole 151 that is penetrated by a connection portion 132 of an electrode terminal 130 described later, along with the through hole 113 of the lid portion 111 and the through hole 162 of the current collecting member 160.

  The external insulating sealing material 120 is an insulating member that insulates the electrode terminal 130 from the container 110 by being disposed between the terminal main body 131 (see below) of the electrode terminal 130 and the lid portion 111. That is, the external insulating sealing material 120 is disposed outside the container 110 and is an insulating member for insulating the container 110 from the electrode body 170 that is electrically connected via the electrode terminal 130 and the current collecting member 160. It is. The external insulating sealing material 120 is a member disposed between the terminal main body 131 and the lid portion 111 of the container 110, and the through hole 113 of the connection portion 132 and the lid portion 111 of the container 110 is formed. It is the member arrange | positioned over the part currently formed. Further, the external insulating sealing material 120 is sealed together with the electrode terminal 130 and the internal insulating sealing material 150 against the through hole 113 formed in the lid portion 111 of the container 110, thereby sealing the through hole 113. It also functions as a sealing material (packing). The external insulating sealing material 120 is arranged on the upper side of the lid portion 111 and is continuously formed from a plate-like plate portion 121 in which the through hole 124 is formed and a portion of the plate portion 121 in which the through hole 124 is formed. And a cylindrical tube portion 123 extending below the plate portion 121. That is, the external insulating sealing material 120 includes a cylindrical portion 123 and a plate portion 121 that extends in the direction intersecting the axis of the cylindrical portion 123 and outside the cylindrical portion 123.

  The external insulating sealing material 120 is a synthetic resin member similar to the internal insulating sealing material 150. The through holes 124 formed in the external insulating sealing material 120 are the through holes 113 formed in the lid portion 111, the through holes 151 formed in the internal insulating sealing material 150, and the through holes formed in the current collecting member 160. Along with 162, it is penetrated by a connecting portion 132 of an electrode terminal 130 described later.

  The cylindrical portion 123 of the external insulating sealing material 120 is formed on the side facing the lid portion 111 (that is, the lower side of the plate portion 121), and the through hole 124 and the inner edge of the cylindrical portion 123 coincide with each other. Yes. The cylindrical portion 123 has an outer shape corresponding to the through holes 113 and 151 and is fitted into the through holes 113 and 151. Accordingly, the cylindrical portion 123 is sandwiched between the through hole 113 formed in the lid portion 111 of the container 110 and the connection portion 132 of the electrode terminal 130. That is, the external insulating sealing material 120 is sandwiched between the terminal body 131 of the electrode terminal 130 and the lid portion 111 of the container 110, and forms the connection portion 132 of the electrode terminal 130 and the through hole 113 of the container 110. The electrode terminal 130 and the container 110 are insulated by being sandwiched between the portions. Further, a frame body 122 is formed on the upper side of the plate portion 121 of the external insulating sealing material 120, and the frame body 122 is formed outside a through hole 124 formed in the plate portion 121.

  The electrode terminal 130 penetrates the container 110 and is connected to the current collecting member 160 and is connected to the current collector 160. The plate-shaped terminal body is disposed outside the container 110 at the end of the connection part 132. 131. Note that the connecting portion 132 extends inward of the container 110. The terminal body 131 has a planar shape in which the outer edge shape corresponds to the inner edge shape of the frame body 122. The connecting portion 132 serves to electrically connect the terminal body 131 and the current collecting member 160 and mechanically join the lid portion 111 and the electrode body 170. Moreover, the electrode terminal 130 arrange | positioned at the positive electrode side is comprised from aluminum or aluminum alloy, and the electrode terminal arrange | positioned at the negative electrode side is comprised from copper or a copper alloy.

  Specifically, the electrode terminal 130 is connected to the storage element 100 and the external load by welding and fixing a terminal of an external load (not shown) (that is, a device that consumes electrical energy of the storage element 100) to the surface of the terminal body 131. This is a member for completing the electrical connection. Alternatively, the electrode terminal 130 is electrically connected between the storage elements 100 by welding and fixing the terminal main body 131 of each battery with a conductive member such as a bus bar in a state where a plurality of storage elements 100 (not shown) are arranged side by side. It is a member for completing.

  In the electrode terminal 130, the terminal main body 131 and the connecting portion 132 may be made of the same material by forging, casting, or the like. The electrode terminal 130 includes a terminal body 131 and a connection portion 132 that are independent of each other, and is formed by integrally molding two different or similar materials constituting the terminal body 131 and the connection portion 132. May be.

  Next, with reference to FIG. 3, the structure around the electrode terminal of the nonaqueous electrolyte secondary battery according to the present embodiment will be described in more detail. FIG. 3 is an enlarged view of the periphery of the electrode terminal in the III-III cross-sectional view of the nonaqueous electrolyte secondary battery of FIG.

  As shown in FIG. 3, the configuration around the electrode terminal 130 of the power storage device 100 includes the electrode terminal 130, the external insulating sealing material 120, the lid 111, the internal insulating sealing material 150, and the plate portion of the current collecting member 160 from the top. The layers are stacked in the order of 161. The external insulating sealing material 120 includes a plate portion 121, a lid portion 111, and an internal insulating sealing material 150 that overlap each other, and a cylindrical portion 123 formed in the lid portion 111 and an internal insulating sealing material. It arrange | positions in the state penetrated to the through-hole 151 formed in 150. FIG. The end surface of the cylindrical portion 123 is flush with the lower surface of the internal insulating sealing material 150 and is in contact with the upper surface of the plate portion 161 of the current collecting member 160 together with the lower surface of the internal insulating sealing material 150. And the shape of the inner periphery of the cylinder part 123 of the external insulation sealing material 120 and the through-hole 162 of the current collection member 160 are the same size and the same shape. The cylindrical portion 123 and the through hole 162 are penetrated by the connection portion 132 of the electrode terminal 130. That is, the outer periphery of the connection part 132, the inner periphery of the cylinder part 123, and the part in which the through-hole 162 is formed are in contact with each other. And the connection part 132 of the electrode terminal 130 is caulked at the tip in a state where it penetrates the cylindrical part 123 of the external insulating sealing material 120 and the through-hole 162 formed in the current collecting member 160, and the caulking end 133 is shaped. Is done. That is, the caulking end 133 is formed by caulking the end of the electrode terminal 130 on the side opposite to the terminal body 131 of the connecting portion 132, and the inner diameter of the cylindrical portion 123 and the diameter of the through hole 162 of the current collecting member 160. The outer diameter is larger than

  Since the outer diameter of the caulking end 133 is larger than the diameter of each of the through holes 124, 113, 151, 162, the outer insulating sealing material 120, the lid portion 111, the inner insulating sealing material 150, and the current collecting member 160 are connected to the electrode terminal 130. By being sandwiched between the terminal body 131 and the caulking end 133, they are crimped to each other and fixed together. As a result, the electrode terminal 130 is bonded to the external insulating sealing material 120 and the lid portion 111 of the container 110, so that the portion between the portion of the container 110 where the through hole 113 is formed and the electrode terminal 130 are sealed with the external insulating seal. Sealing is performed with the stopper 120 and the internal insulating sealing material 150. The electrode terminal 130 is electrically connected to the current collecting member 160 in a state of penetrating the lid 111 because the connecting portion 132 and the crimping end 133 are in contact with the current collecting member 160. In addition, since the side surface of the connection part 132 is covered with the cylinder part 123 of the external insulation sealing material 120, the insulation state is ensured between the cover part 111 and the connection part 132. FIG.

  Next, the individual configuration of each unit will be described.

  As shown in FIG. 3, the terminal body 131 of the electrode terminal 130 is formed such that the first interval d1 is smaller than ½ of the second interval d2. The first interval d1 is the interval between the terminal body 131 and the lid portion 111 of the container 110 at the first position P1 of the terminal body 131. The second distance d2 is the distance between the terminal body 131 and the lid portion 111 of the container 110 at the second position P2 that is closer to the connecting portion 132 than the first position P1.

  In the present embodiment, the first position P1 is a position on the terminal main body 131 and a position farthest from the connecting portion 132. In the present embodiment, the second position P <b> 2 is a position on the terminal main body 131 and a position closest to the connection portion 132. Further, in the present embodiment, the distance between the terminal main body 131 and the lid portion 111 of the container 110 is between the lower surface of the terminal main body 131 and the upper surface of the lid portion 111 (all planes that coincide with the upper surface). Is the interval.

  Note that the first position P1 and the second position P2 are not limited to the farthest position and the latest position from the connection part 132 as described above, but the first position is closer to the connection part 132 than the second position. Any remote location is acceptable. That is, even in such a case, the first interval at the first position is smaller than the second interval at the second position. In this case, the distance between the terminal main body 131 and the lid portion 111 of the container 110 at a position farthest from the connecting portion 132 in the terminal main body 131 which is a position different from the first position is different from the second position. It is good also as a structure smaller than the space | interval of the terminal main body 131 and the cover part 111 of the container 110 in the position nearest to the connection part 132 in the terminal main body 131 which is a position.

  Further, the terminal main body 131 is formed so that the distance between the terminal main body 131 and the lid portion 111 of the container 110 becomes smaller from the second position P2 toward the first position P1. More specifically, in the terminal body 131, the surface 131a of the terminal body 131 on the lid 111 side of the container 110 of the terminal body 131 is the surface of the container 110 on the terminal body 131 side between the first position P1 and the second position P2. It is inclined linearly with respect to 111a (that is, the upper surface). Further, the surface 121 a on the terminal main body 131 side of the external insulating sealing material 120 has an inclination corresponding to the surface 131 a on the lid 111 side of the container 110 of the terminal main body 131.

  Further, the lid portion 111 of the container 110 is formed so that the third interval d3 is smaller than the fourth interval d4 in the portion facing the connection portion 132 (that is, the portion where the through hole 113 is formed). ing. The third distance d3 is the distance between the connection part 132 and the lid part 111 of the container 110 at the third position P3 of the lid part 111 of the container 110. The fourth distance d4 is the distance between the connecting portion 132 and the container at the fourth position P4 located on the outer side of the lid portion 111 of the container 110 with respect to the third position P3. That is, the through hole 113 formed in the lid portion 111 of the container 110 is formed so that the diameter thereof becomes smaller toward the inside of the container 110.

  In the present embodiment, the third position P3 is a position on the lid portion 111 of the container 110 and is a position on the outermost side of the lid portion 111 of the container 110. Further, in the present embodiment, the fourth position P4 is a position on the lid portion 111 of the container 110 and is a position on the innermost side of the lid portion 111 of the container 110. The third position and the fourth position are not limited to the outermost position and the innermost position of the lid portion 111 of the container 110 as described above, but the third position is more than the fourth position. What is necessary is just the outside position.

  Further, the lid portion 111 of the container 110 is formed so that the distance between the connection portion 132 and the lid portion 111 of the container 110 becomes smaller as it goes from the fourth position P4 to the third position P3. More specifically, in the lid portion 111 of the container 110, the surface 111b facing the connection portion 132 of the lid portion 111 of the container 110 is between the third position P3 and the fourth position P4. It is inclined linearly with respect to the surface 132a.

(Feature)
According to the electricity storage device 100 according to the present embodiment, the shape of the terminal main body 131 is such that the first distance d1 between the terminal main body 131 and the lid portion 111 of the container 110 at the first position P1 is more connected than at the first position P1. It is smaller than the second distance d2 between the terminal body 131 and the lid portion 111 of the container 110 at the second position P2 close to the portion 132. The external insulating sealing material 120 is sandwiched between the terminal body 131 and the container 110 and receives a pressing force from both. That is, the space in which the external insulating sealing material 120 is disposed is the terminal body 131 and the container at the first position P1, which is a position far from the connection portion 132 of the electrode terminal 130, in a direction intersecting the direction of the pressing force. The space | interval with the cover part 111 of 110 is narrow. For this reason, even if the external insulating sealing material 120 is thermally expanded in a high-temperature environment, it is possible to suppress the external insulating sealing material 120 from expanding toward the direction intersecting the direction of the pressing force. Thereby, even if the external insulating sealing material 120 is thermally expanded, the external insulating sealing material 120 can be kept within a predetermined range, so that the sealing performance in the vicinity of the electrode terminal 130 can be sufficiently maintained. .

  In addition, according to power storage device 100 according to the present exemplary embodiment, external insulating sealing material 120 is arranged between terminal body 131 and lid portion 111 of container 110. Further, the external insulating sealing material 120 is disposed between the connection portion 132 and the lid portion 111 of the container 110. That is, the external insulating sealing material 120 is filled between the electrode terminal 130 (the terminal main body 131 and the connecting portion 132) and the lid portion 111 of the container 110 without a gap. For this reason, the sealing performance in the vicinity of the electrode terminal 130 can be improved. In addition, since the external insulating sealing material 120 is filled between the electrode terminal 130 and the lid portion 111 of the container 110 without any gap, it easily expands in a direction that intersects the direction of the pressing force when thermally expanded. However, the space in which the external insulating sealing material 120 is disposed is such that the terminal body 131 and the lid portion 111 of the container 110 become farther away from the terminal body 131 and the connection portion 132 of the electrode terminal 130 in the direction intersecting the direction of the pressing force. And the interval between the connection portion 132 and the lid portion 111 of the container 110 are narrowed, so that the external insulating sealing material 120 can be prevented from expanding in a direction intersecting the direction of the pressing force.

  Moreover, according to the electrical storage element 100 according to the present embodiment, the terminal body 131 and the lid portion of the container 110 as the terminal body 131 moves away from the connection portion 132 between the first position P1 and the second position P2. It is formed so that the distance from 111 is small. For this reason, during the thermal expansion of the external insulating sealing material 120, when the external insulating sealing material 120 expands in the direction intersecting the direction of the pressing force, it is between the first position P1 and the second position P2. The force applied to the external insulating sealing material 120 can be dispersed. Specifically, this force is a force that prevents the outer insulating sealing material 120 from expanding in a direction farther than the connection portion 132, and is a force directed in a direction closer to the connection portion 132. . Thereby, compared with the thing of the structure where the space | interval between the terminal main body 131 and the cover part 111 of the container 110 becomes small rapidly, identification of the terminal main body 131, the cover part 111 of the container 110, or the external insulation sealing material 120 is specified. It is possible to prevent a large force from being applied to these parts, and it is possible to prevent the terminal main body 131, the lid 111 of the container 110, or the external insulating sealing material 120 from being damaged.

  In addition, according to power storage device 100 according to the present exemplary embodiment, surface 131a of container 110 of terminal body 131 on the lid 111 side is linear with respect to surface 111a of lid 110 of container 110 on the side of terminal body 131. It is inclined to. For this reason, during the thermal expansion of the external insulating sealing material 120, when the external insulating sealing material 120 expands in the direction intersecting the direction of the pressing force, it is between the first position P1 and the second position P2. With respect to the external insulating sealing material 120, the force directed in the direction close to the connecting portion 132 can be made uniform at least between the first position P1 and the second position P2. Thus, between the first position P1 and the second position P2, the force applied to the terminal body 131, the lid portion 111 of the container 110, or the external insulating sealing material 120 can be equalized. The applied force can be minimized. For this reason, it can prevent more effectively that the terminal main body 131, the cover part 111 of the container 110, or the external insulation sealing material 120 is damaged.

  Moreover, according to the electrical storage element 100 according to the present embodiment, the shape of the lid portion 111 of the container 110 is such that the third distance d3 between the connection portion 132 and the lid portion 111 of the container 110 at the third position P3 is third. It is smaller than the fourth distance d4 between the connecting portion 132 and the lid portion 111 of the container 110 at the fourth position P4 on the outer side of the lid portion 111 of the container 110 than the position P3. The external insulating sealing material 120 is sandwiched between the connecting portion 132 and the lid portion 111 of the container 110, and when thermally expanded, the external insulating sealing material 120 tends to expand in a direction crossing the direction of the pressing force. . At this time, since the third interval d3 at the third position P3 that is the position on the inner side of the lid portion 111 of the container 110 is narrower than the fourth interval d4, even if the external insulating sealing material 120 is thermally expanded, It is possible to suppress the external insulating sealing material 120 from expanding toward the inner side of the lid portion 111 of the container 110. As a result, when the external insulating sealing material 120 is thermally expanded, the external insulating sealing material 120 can be kept within a predetermined range in the axial direction of the connecting portion 132, so that the seal near the electrode terminal 130 can be maintained. Sex can be sufficiently maintained.

  Moreover, according to the electrical storage element 100 according to the present embodiment, the lid portion 111 of the container 110 is connected to the connection portion 132 and the container 110 as the distance from the terminal body 131 increases between the third position P3 and the fourth position P4. The gap with the lid portion 111 is formed to be small. For this reason, during the thermal expansion of the external insulating sealing material 120, when the external insulating sealing material 120 expands in the direction intersecting the direction of the pressing force, it is between the third position P3 and the fourth position P4. The force applied to the external insulating sealing material 120 can be dispersed. Note that this force is specifically a force that prevents the outer insulating sealing material 120 from expanding toward the inside of the container 110 and is a force that is directed toward the terminal main body 131. Thereby, compared with the thing of the structure where the space | interval between the connection part 132 and the cover part 111 of the container 110 becomes small rapidly, identification of the terminal main body 131, the cover part 111 of the container 110, or the external insulation sealing material 120 is specified. It is possible to prevent a large force from being applied to these parts, and it is possible to prevent the terminal main body 131, the lid 111 of the container 110, or the external insulating sealing material 120 from being damaged.

  In addition, according to power storage element 100 according to the present exemplary embodiment, surface 111b of connecting portion 132 side of lid portion 111 of container 110 is inclined linearly with respect to surface 132a of connecting portion 132. For this reason, during the thermal expansion of the external insulating sealing material 120, when the external insulating sealing material 120 expands in the direction intersecting the direction of the pressing force, it is between the third position P3 and the fourth position P4. With respect to the external insulating sealing material 120, the force directed in the direction close to the connection portion 132 can be made uniform at least between the third position P3 and the fourth position P4. Thus, between the third position P3 and the fourth position P4, the force applied to the terminal body 131, the lid portion 111 of the container 110, or the external insulating sealing material 120 can be equalized. The applied force can be minimized. For this reason, it can prevent that the terminal main body 131, the cover part 111 of the container 110, or the external insulation sealing material 120 is damaged.

  In addition, according to power storage device 100 according to the present exemplary embodiment, external insulating sealing material 120 and lid portion 111 of container 110 are pressed by electrode terminal 130, so that through hole 113 of lid portion 111 of container 110 is formed. The portion to be formed and the terminal body 131 are sealed with an external insulating sealing material 120. For this reason, the external insulating sealing material 120 is in a state in which a pressing force is always applied between the terminal main body 131 and the lid portion 111 of the container 110 by the electrode terminal 130. Even if the external insulating sealing material 120 is in such a state that it is always applied with a pressing force and is likely to expand in the direction crossing the pressing force when thermally expanded, the space ahead of the direction crossing the pressing force Therefore, the expansion | swelling to the said direction of the external insulation sealing material 120 can be suppressed.

(Modification)
As mentioned above, although the electrical storage element of this invention was demonstrated based on embodiment, this invention is not limited to this embodiment. Unless it deviates from the meaning of this invention, the form which carried out the various deformation | transformation which those skilled in the art can think to this embodiment, and the structure constructed | assembled combining the component in different embodiment is also contained in the scope of the present invention. .

(1)
According to the electricity storage device 100 according to the above-described embodiment, the terminal main body 131 is configured such that the surface 131a on the lid 111 side of the container 110 of the terminal main body 131 is between the first position P1 and the second position P2. Although it inclines linearly with respect to the surface 111a by the side of the terminal main body 131 of the cover part 111, it does not restrict to inclining linearly.

  For example, it is good also as the terminal main body 231 of the electrode terminal 230 shown in FIG. FIG. 4 is an enlarged view of the modified example (1) in which the periphery of the electrode terminal in the III-III cross-sectional view of the nonaqueous electrolyte secondary battery in FIG. 1 is enlarged. As shown in FIG. 4, in the terminal body 231, the first interval d11 in the first region R1 including the first position P11 and the second interval d2 in the second region R2 including the second position P12 are stepwise different. It may be formed as follows. That is, the terminal main body 231 has a convex portion 231a that extends downward in the lower portion of the first region R1. Further, in this case, the plate portion 221 of the external insulating sealing material 220 is formed with a concave portion 221a for fitting the convex portion 231a at a position facing the convex portion 231a of the terminal body 231. In FIG. 4, the same components as those in FIG. 3 are denoted by the same reference numerals.

  According to this, the shape of the terminal body 231 is formed such that the first interval d11 in the first region R1 and the second interval d12 in the second region R2 are different in stages. For this reason, in the terminal main body 231, the shape where the 1st space | interval d11 becomes narrow can be manufactured easily.

(2)
For example, it is good also as the terminal main body 331 of the electrode terminal 330 shown in FIG. FIG. 5 is an enlarged view enlarging the periphery of the electrode terminal in the III-III cross-sectional view of the nonaqueous electrolyte secondary battery of FIG. 1 in Modification (2). As shown in FIG. 5, the terminal main body 331 is formed such that the distance between the terminal main body 331 and the lid portion 111 of the container 110 is gradually reduced from the second position P22 toward the first position P21. . In other words, the terminal main body 331 only needs to monotonously decrease as the distance between the terminal main body 331 and the lid portion 111 of the container 110 moves from the second position P22 to the first position P21. In FIG. 5, the same components as those in FIG. 3 are denoted by the same reference numerals.

(3)
Further, according to power storage element 100 according to the above embodiment, lid portion 111 of container 110 is connected to connecting portion 132 and container 110 at third position P3 of lid portion 111 of container 110 at a portion facing connecting portion 132. The fourth distance between the connection part 132 and the lid part 111 of the container 110 at the fourth position P4 is located on the outer side of the lid part 111 of the container 110 from the third position P3. Although it is formed to be smaller than d4, it is not limited to this. For example, it is good also as the cover part 411 of the container 410 as shown in FIG. FIG. 6 is an enlarged view enlarging the periphery of the electrode terminal in the III-III cross-sectional view of the nonaqueous electrolyte secondary battery of FIG. 1 in Modification (3). Like the lid portion 411 of the container 410 shown in FIG. 6, the third distance d13 between the connecting portion 132 and the lid portion 111 of the container 110 at the third position P13, and the lid portion 411 of the container 410 from the third position P13. The fourth gap d14 between the connecting portion 132 and the lid portion 411 of the container 410 at the fourth position P14 on the outer side may be the same shape. That is, the through hole 413 formed in the lid portion 411 of the container 410 has the same diameter regardless of whether it is an inner position or an outer position of the container 410. In FIG. 6, the same components as those in FIG. 3 are denoted by the same reference numerals.

(4)
Moreover, according to the electrical storage element 100 according to the above-described embodiment and each of the modifications described above, the shape (specifically, the thickness) of the terminal body 131 differs between the first position P1 and the second position P2. Thus, the first interval d1 and the second interval d2 are formed to be different from each other. However, the present invention is not limited to this. For example, it is good also as a shape which the shape of the cover part of a container approaches a terminal main body as it goes to a 1st position from a 2nd position.

  INDUSTRIAL APPLICABILITY The present invention is useful as a power storage element that can improve the sealing performance in the vicinity of the electrode terminal of the power storage element and can maintain the sealing performance.

100 Storage element 110, 410 Container 111, 411 Lid portion 111a Surface 111b Surface 112 Container body 113, 413 Through hole 114 Opening portion 120, 220 External insulation sealing material 121, 221 Plate portion 121a Surface 122 Frame body 123 Tube portion 124 Through Holes 130, 230, 330 Electrode terminals 131, 231, 331 Terminal body 131 a surface 132 connection portion 132 a surface 133 caulking end 150 internal insulating sealing material 151 through hole 160, 164 current collecting member 161 plate portion 162 through hole 163 arm portion 170 Electrode bodies 171 and 172 Protruding part 221a Concave part 231a Convex part 500 PPS material 510 Plate-like member 520 Restricting member

Claims (10)

A container, an electrode body housed in the container, an electrode terminal, a current collecting member that electrically connects the electrode terminal and the electrode body, and an insulating member that insulates the container from the electrode terminal; A storage element comprising:
The electrode terminal penetrates the container and is connected to the current collector, a columnar connection part, and a plate-like terminal body that is an end of the connection part and is disposed outside the container. Have
The insulating member is
Insulating the container and the electrode terminal by being disposed between the container and the connection portion and the terminal body,
At least one of the terminal body and the container is such that the distance between the terminal body and the container decreases from the second position of the terminal body toward the first position that is farther from the connection portion than the second position. An electricity storage element formed to be. The at least one of the terminal main body and the container has a first distance between the terminal main body and the container at the first position that is smaller than ½ of a second distance at the second position. Power storage element. A container, an electrode body housed in the container, an electrode terminal, a current collecting member that electrically connects the electrode terminal and the electrode body, and an insulating member that insulates the container from the electrode terminal; A storage element comprising:
The electrode terminal penetrates the container and is connected to the current collector, a columnar connection part, and a plate-like terminal body that is an end of the connection part and is disposed outside the container. Have
The insulating member is
Insulating the container and the electrode terminal by being disposed between the container and the connection portion and the terminal body,
At least one of the terminal main body and the container has the terminal main body in a second position where the first distance between the terminal main body and the container in the first position of the terminal main body is closer to the connecting portion than the first position. And an electric storage element formed to be smaller than ½ of the second distance between the container and the container. At least one of the terminal main body and the container has at least a distance between the container and a portion of the terminal main body that is farthest from the connection portion and a distance between the container and the portion of the terminal main body that is closest to the connection portion. The power storage element according to any one of claims 1 to 3, wherein the power storage element is formed to be smaller. In at least one of the terminal body and the container, the container side surface of the terminal body is linear with respect to the terminal body side surface of the container between the first position and the second position. The power storage element according to any one of claims 1 to 4, wherein The at least one of the terminal body and the container has a stepwise difference between the first interval in the first region including the first position and the second interval in the second region including the second position. The electrical storage element as described in. The container has a fourth position where a third distance between the connection portion and the container at a third position of the container is located on an outer side of the container with respect to the third position at a portion facing the connection portion. The electrical storage element according to claim 1, wherein the electrical storage element is formed so as to be smaller than a fourth interval between the connection portion and the container. The power storage device according to claim 7, wherein the container is formed such that a distance between the connection portion and the container becomes smaller from the fourth position toward the third position. The surface of the container that faces the connection portion of the container is inclined linearly with respect to the surface of the connection portion between the third position and the fourth position. The electrical storage element as described in. The said electrode terminal seals between the part in which the through-hole of the said container is formed, and the said terminal main body by the said insulating member by crimping | bonding the said insulating member and the said container. The electrical storage element of 1 item | term.

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