JP2015191825A - Power storage device and power storage module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device and a power storage module that are able to improve actuation pressure accuracy in a current cut-off device.SOLUTION: A power storage device comprises: an electrode assembly 80 in which a positive electrode and a negative electrode are stacked via a separator; a case 7 accommodating the electrode assembly; and a current cut-off device 3 configured to block a power supply path between the electrode assembly and a negative electrode terminal by a first deformable plate 31 and a second deformable plate 35, which are provided between the electrode assembly and the negative electrode terminal, electrically connecting the electrode assembly and the negative electrode terminal, and deformed when pressure in the case rises beyond a predetermined level. The negative electrode terminal connected to the current cut-off device is provided with a communication hole communicating a first space that is separated from the inside space of the case by the deformable plates and that is the space between the deformable plates and the negative electrode terminal, and a second space that is the outside space of the case.

Description

  The present invention relates to a power storage device and a power storage module having a current interruption function.

  Secondary batteries such as lithium ion batteries, electric double layer capacitors, and the like are known as power storage devices. In these power storage devices, an electrode assembly and an electrolytic solution are accommodated in a sealed case. In such a power storage device, a charging current larger than usual flows due to some abnormality during charging, and as a result, an overcharged state may occur, and gas may be generated in the case. In this case, in the sealed power storage device, the pressure inside the case increases and the case may be damaged.

  Regarding this problem, in the power storage device disclosed in Patent Document 1, a current interrupt device (CID) is provided between the electrode terminal and the electrode assembly. The current interrupting device includes an energization path that connects the electrode terminal and the electrode assembly, and a deformation plate that deforms toward the outside of the case when the pressure inside the case rises above a predetermined level. The energization path is physically broken by the deformation of the deformation plate when the pressure inside the case rises.

JP 2010-212034 A

  However, in the conventional power storage device, the space on the side corresponding to the outside of the case in the reversing plate is completely sealed. However, the pressure in the sealed space may increase due to deformation of the reversal plate, temperature, minute leakage of gas from the case internal space, and the like. If the pressure in the space in contact with the outer side of the deformable plate increases, there is a risk that the pressure difference between both spaces disappears and the current interrupting device does not operate. That is, the operating pressure accuracy in the current interrupt device is reduced.

  Then, an object of this invention is to provide the electrical storage apparatus and electrical storage module which can improve the operating pressure precision in an electric current interruption apparatus.

  The power storage device of the present invention includes an electrode assembly in which a positive electrode and a negative electrode are stacked with a separator interposed therebetween, a case that accommodates the electrode assembly, a positive electrode terminal and a negative electrode terminal that are provided so as to protrude from the case, and an electrode assembly Provided between at least one of the three-dimensional body and the positive electrode terminal and between the electrode assembly and the negative electrode terminal to electrically connect the electrode assembly and the positive electrode terminal or the negative electrode terminal, and the pressure inside the case is predetermined. A current interrupting device that interrupts a current-carrying path between the electrode assembly and the positive electrode terminal or the negative electrode terminal by a deforming plate that deforms when rising above the level, and is connected to the current interrupting device. The first space that is a space between the deformation plate and the positive electrode terminal or the negative electrode terminal and the second space that is an outer space of the case are communicated with each other by being separated from the space inside the case by the deformation plate. Ream Holes are provided.

  In this power storage device, the deformation plate separates the space inside the case from the first space formed between the deformation plate and the positive electrode terminal or the negative electrode terminal, and the second space that is the space outside the case. , Is communicated. For this reason, 1st space is hold | maintained at the pressure of the space outside a case. As a result, it is easy to keep the pressure in the first space where the surface opposite to the pressure receiving surface inside the case is exposed in the deformed plate at a constant level. For example, even if gas leaks from the space inside the case to the first space, it is possible to prevent the gas from escaping to the second space and increasing the pressure in the first space. For this reason, when the pressure in the space inside the case increases due to overcharging or the like, a pressure difference between the first space and the space inside the case is likely to be generated. As a result, in the case of overcharge or the like, it is possible to suppress the malfunction of the current interrupting device due to the insufficient pressure difference between the space inside the case and the first space. That is, the operating pressure accuracy in the current interrupt device can be improved.

  In the power storage device of the present invention, the communication hole may be formed in a straight line, and the deformation plate may be positioned on an extension line of the axis of the communication hole.

  According to this power storage device, if a straight bar-shaped member is inserted into the communication hole, the deformable plate can be pressed at the tip of the bar-shaped member. Thereby, a deformation | transformation board can be easily returned to the state before a deformation | transformation.

  In the power storage device of the present invention, a portion where the energization path is blocked by the deformation plate may be located on an extension of the axis of the communication hole.

  According to this power storage device, the deformable plate can be returned to the state before deformation more easily.

  The power storage device of the present invention may further include a linear rod-shaped member inserted into the communication hole, and one end of the rod-shaped member may be disposed in contact with the deformation plate.

  According to this power storage device, when the current interrupting device is activated, it is lifted upward along the axial direction of the communication hole by the deformation plate. Thereby, the presence or absence of the operation | movement in an electric current interruption apparatus can be easily confirmed only by confirming the position of a rod-shaped member from a communicating hole.

  In the power storage device of the present invention, a permeable film that blocks the communication hole may be provided at the end of the communication hole on the second space side.

  According to this power storage device, it is possible to prevent foreign matter from entering the communication hole while securing the gas flow between the first space and the second space.

  The power storage device may be a secondary battery.

  The power storage module of the present invention includes a plurality of power storage devices configured as described above, and these power storage devices are electrically connected by a connection member.

  In the power storage module having this configuration, the operating pressure accuracy in the current interrupting device of each power storage device is improved. Thereby, a highly safe power storage module can be provided.

  In the power storage module of the present invention, the positive electrode terminal and the negative electrode terminal to which the current interrupting device is connected communicate with the first space, and the hole for penetrating the fastening member for fastening the connection member to the positive electrode terminal or the negative electrode terminal The connecting member is fastened to the positive electrode terminal or the negative electrode terminal by a fastening member inserted into the hole, and the fastening member has a through hole penetrating in the axial direction, and a communication hole is formed by the through hole. May be.

  The connecting member is fastened by penetrating the fastening member into the positive terminal and the negative terminal having a hole for penetrating the fastening member for communicating with the first space and fastening the connecting member to the positive terminal or the negative terminal. In the power storage module configured as described above, the pressure in the first space may not be released to the second space depending on the penetration state of the fastening member. In the power storage module having this configuration, a through hole penetrating in the axial direction is provided in a fastening member that is inserted into the hole. For this reason, the pressure of the first space can be released to the second space regardless of the penetration state of the fastening member. As a result, in the case of overcharge or the like, it is possible to suppress the malfunction of the current interrupting device due to the insufficient pressure difference between the space inside the case and the first space. That is, the operating pressure accuracy in the current interrupt device can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the working pressure precision in an electric current interruption apparatus can be improved.

It is a perspective view which shows a battery module provided with the secondary battery which concerns on one Embodiment. It is sectional drawing of the secondary battery which concerns on one Embodiment. It is sectional drawing which expanded and showed the vicinity of the negative electrode terminal shown in FIG. 2, and the electric current interruption apparatus in the normal time. It is sectional drawing which expanded and showed the vicinity of the negative electrode terminal shown in FIG. 2, and the electric current interruption apparatus at the time of an operation | movement. It is the perspective view which expanded the connection part of the secondary batteries shown in FIG. It is sectional drawing which expanded and showed the vicinity of the negative electrode terminal of the secondary battery which concerns on other embodiment, and the electric current interruption apparatus in normal time. It is sectional drawing which expanded and showed the vicinity of the negative electrode terminal of the secondary battery which concerns on other embodiment, and the electric current interruption apparatus in normal time. It is sectional drawing which expanded and showed the vicinity of the negative current terminal of the secondary battery which concerns on other embodiment, and the electric current interruption apparatus at the time of an operation | movement.

  Hereinafter, an embodiment will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. The dimensional ratios in the drawings do not necessarily match those described. In the description, terms indicating directions such as “up” and “down” are convenient terms based on the state shown in the drawings.

  FIG. 1 is a schematic diagram illustrating a schematic configuration of a battery module (power storage module) 100 including a secondary battery (power storage device) 1 according to an embodiment. The battery module 100 includes a plurality of secondary batteries 1. The number of secondary batteries 1 is appropriately determined according to the use of the battery module 100. The secondary battery 1 as the power storage device is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery, for example. The structure of the secondary battery 1 will be described in detail later.

  In the plurality of secondary batteries 1, the negative terminal 87 of one secondary battery 1 of the adjacent secondary batteries 1 and 1 and the positive terminal 89 of the other secondary battery 1 are electrically connected by a connecting member 95. ing. Examples of the connection member 95 include a cable and a bus bar. Hereinafter, an example in which a bus bar is employed as the connection member 95 will be described. The connection configuration of each terminal (the negative electrode terminal 87 and the positive electrode terminal 89) and the connection member 95 in the secondary battery 1 will be described in detail later.

  The plurality of secondary batteries 1 are arranged in parallel. The arrangement direction of the plurality of secondary batteries 1 is a direction substantially orthogonal to a straight line connecting the axes of the negative electrode terminal 87 and the positive electrode terminal 89 arranged in one case 7. Between the secondary batteries 1, while preventing that the secondary batteries 1 are short-circuited, the partition part 97 called a heat sink may be provided for heat dissipation.

  Next, the secondary battery 1 provided in the current interrupt device 3 will be described mainly with reference to FIGS. FIG. 2 is a cross-sectional view of the secondary battery 1 according to an embodiment. As shown in FIG. 2, the secondary battery 1 includes a case 7, an electrode assembly 80, a negative electrode terminal 87, a positive electrode terminal 89, and a current interrupt device 3.

  The case 7 has a bottomed cylindrical main body 71 that houses the electrode assembly 80 and a lid 73 that closes the opening of the main body 71. More specifically, the main body portion 71 has a rectangular box shape, and the lid portion 73 has a rectangular flat plate shape. The main body 71 and the lid 73 are made of a metal such as stainless steel or aluminum, for example. In the following description, the main body 71 and the lid 73 may be simply referred to as the case 7. The case 7 contains an electrode assembly 80 and is filled with, for example, an organic solvent-based or non-aqueous electrolyte. An insulating sheet 75 is provided on the inner surface of the case 7. The lid portion 73 of the case 7 is provided with a negative electrode terminal 87 and a positive electrode terminal 89. The case 7 becomes a sealed container by welding the main body 71 and the lid 73.

  The electrode assembly 80 includes a plurality of sheet-like positive electrodes, a plurality of sheet-like negative electrodes, and a plurality of sheet-like separators disposed between the positive and negative electrodes. The electrode assembly 80 is a stacked electrode assembly in which a plurality of positive electrodes and a plurality of negative electrodes are alternately stacked via separators.

  The positive electrode has, for example, a metal foil made of an aluminum foil and a positive electrode active material layer formed on both surfaces of the metal foil. The positive electrode active material layer is formed including a positive electrode active material and a binder. Examples of the positive electrode active material include composite oxide, metallic lithium, sulfur, and the like. Examples of the composite oxide include, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium.

  A positive electrode current collector 82 is formed at the upper edge of the positive electrode (the edge of the positive electrode on the opening side of the main body 71). The positive electrode current collector 82 extends to one end in the stacking direction of the electrode assembly 80 and is aggregated and electrically connected to the positive electrode terminal 89. In the present embodiment, the positive electrode current collector 82 and the positive electrode terminal 89 are indirectly connected by the positive electrode conductive member 81. The positive electrode current collector 82 and the positive electrode conductive member 81, and the positive electrode conductive member 81 and the positive electrode terminal 89 are joined by welding, for example.

  On the other hand, the negative electrode has, for example, a metal foil made of copper foil and a negative electrode active material layer formed on both surfaces of the metal foil. The negative electrode active material layer is formed including a negative electrode active material and a binder. Examples of the negative electrode active material include, for example, graphite, highly oriented graphite, mesocarbon microbeads, carbon such as hard carbon and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5) and the like, as well as boron-added carbon.

  A negative electrode current collector 84 is formed at the upper edge of the negative electrode (the edge of the negative electrode on the opening side of the main body 71). The negative electrode current collector 84 extends to one end in the stacking direction of the electrode assembly 80 and is aggregated and electrically connected to the negative electrode terminal 87. In the present embodiment, a negative electrode conductive member 83 is electrically connected to the negative electrode current collector 84. A current interrupt device 3 is provided below the negative electrode terminal 87. The current interrupt device 3 is provided between the negative electrode terminal 87 and the negative electrode conductive member 83, and the negative electrode terminal 87 and the negative electrode conductive member 83 are electrically connected in series via the current interrupt device 3. That is, the negative electrode terminal 87 and the negative electrode current collector 84 are indirectly and electrically connected in series via the negative electrode conductive member 83 and the current interrupt device 3. The negative electrode current collector 84 and the negative electrode conductive member 83, and the negative electrode conductive member 83 and the current interrupt device 3 are joined by welding, for example.

  Examples of the separator material include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric or a non-woven fabric made of polypropylene, polyethylene terephthalate (PET), methylcellulose, and the like. .

  Further, the negative electrode terminal 87 and the lid portion 73 of the case 7 and the positive electrode terminal 89 and the lid portion 73 of the case 7 are insulated by an insulating sheet or the like. Further, the negative electrode conductive member 83 and the positive electrode conductive member 81 are insulated from the case 7 by an insulating sheet 75 attached to the lid portion 73 of the case 7.

  Next, the current interrupting device 3 will be described with reference to FIGS. 3 and 4. FIG. 4 is an enlarged cross-sectional view showing the vicinity of the negative electrode terminal 87 and the current interrupting device 3 in a normal state. FIG. 5 is an enlarged sectional view showing the vicinity of the negative electrode terminal 87 and the current interrupting device 3 during operation. 3 and 4, illustration of an electrode assembly 80 (see FIG. 2) including a positive electrode and a negative electrode is omitted. The electrode assembly 80 is disposed below the FIGS. 3 and 4. 3 and 4, the illustration of the insulating sheet 75 interposed between the negative electrode terminal 87 and the case 7 is omitted.

  As described above, the current interrupt device 3 is provided between the negative electrode terminal 87 and the negative electrode conductive member 83 (that is, the negative electrode current collector 84). The current interrupt device 3 has an energization path P, which will be described later, and connects the negative electrode terminal 87 and the negative electrode conductive member 83 (that is, the negative electrode current collector 84) in series via the energization path P. As described above, the current interrupt device 3 electrically connects the electrode assembly 80 and the negative electrode terminal 87. The current interrupting device 3 interrupts the energization between the electrode assembly 80 and the negative electrode terminal 87 by interrupting the energizing path P when the pressure inside the case 7 rises above a predetermined level.

  The above-mentioned “predetermined level of pressure” refers to a case where the secondary battery 1 is overcharged (overvoltage) or the secondary battery 1 is overheated (thermal runaway temperature of the active material). 7 internal pressure. The “predetermined level of pressure” is set according to conditions such as the capacity and output voltage of the secondary battery 1. In the secondary battery 1, the current interrupt device 3 is disposed below the negative electrode terminal 87. However, the position where the current interrupt device 3 is arranged is not limited to the position below the negative electrode terminal 87. The current interrupt device 3 may be disposed at any position as long as the electrode assembly 80 and the negative electrode terminal 87 can be electrically connected in series via the current interrupt device 3.

  The current interrupting device 3 is disposed inside the case 7 of the secondary battery 1, and is sealed so that gas in the space inside the case 7 (outside the current interrupting device 3) does not flow inside the current interrupting device 3. Has been. The structure of the current interrupt device 3 will be described in order from the inside of the case 7 of the secondary battery 1 (downward in FIG. 3) to the outside of the case 7 (upward in FIG. 3). As shown in FIG. 4, the current interrupt device 3 includes a first deformation plate (deformation plate) 31 having a pressure receiving surface 31 </ b> A, a current supply plate 33, a second deformation plate (deformation plate) 35, and a sealing lid 50. , A projection 43, a support member 41, and a caulking member 42.

  The first deformable plate 31 is formed of a thin plate and is formed so that the center portion protrudes. An example of the first deformable plate 31 is a metallic diaphragm. The first deformation plate 31 is disposed so that the center portion protrudes downward (on the electrode assembly 80 side), and the outer peripheral portion is fixed to the insulating support member 41. An insulating protrusion 43 is provided at the center of the surface of the first deformable plate 31 on the side opposite to the surface on the electrode assembly 80 side (surface on the side of the energizing plate 33 described later). The shape of the protrusion 43 is, for example, a cylindrical shape. At least a part of the case 7 is exposed inside the case so that the first deformation plate 31 deforms when the pressure inside the case 7 increases. That is, the first deformation plate 31 is disposed on the outer portion of the current interrupt device 3 and forms the outer surface of the current interrupt device 3.

  The energization plate 33 is formed in a plate shape with a conductive member, and is electrically connected to the negative electrode conductive member 83 of the electrode assembly 80. In the present embodiment, the energizing plate 33 is formed so that the central portion is thinner than the other portions of the energizing plate 33. Specifically, a depression is provided in the central portion of the energization plate 33.

  The energizing plate 33 is provided above the first deformable plate 31 so that the central portion faces the protrusion 43 and is spaced apart from the first deformable plate 31 by a predetermined distance. The “predetermined interval” is an interval at which the central portion of the energization plate 33 is not destroyed by vibration when mounted on an automobile, for example. An outer peripheral portion of the energization plate 33 is fixed to an insulating support member 41 and an insulating member 38 is provided on a surface opposite to the surface on the first deformation plate 31 side. A breaking groove 33B is provided at the center of the energizing plate 33 around the portion that contacts the protrusion 43 when the pressure inside the case 7 reaches a predetermined level.

  The second deformation plate 35 is formed of a conductive thin plate, and is formed so that the center portion protrudes. An example of the second deformation plate 35 includes a metal diaphragm having conductivity. The second deformable plate 35 is disposed on the upper side of the current supply plate 33 so that the central portion protrudes downward (on the current supply plate 33 side) and comes into contact with the current supply plate 33. It is fixed. The second deformation plate 35 is deformed in conjunction with the deformation of the first deformation plate 31 as described in detail later.

  The sealing lid 50 is a conductive member provided above the second deformation plate 35. The sealing lid 50 is electrically connected to the second deformation plate 35. The sealing lid 50 has a main body 51 and a cylinder 53. The main body 51 has a disk shape. A concave portion 51 </ b> A that is recessed upward (on the side away from the second deformation plate 35) is provided on the surface of the main body 51 that faces the central portion of the second deformation plate 35. More specifically, the central portion of the main body 51 is recessed above the outer periphery of the main body 51 (the portion in contact with the second deformation plate 35). The recess 51A forms a space S11 for deforming the second deformation plate 35 upward.

  Note that a hole 35C and a hole 33C are formed in the second deformable plate 35 and the energizing plate 33, respectively, and the space S11 between the second deformable plate 35 and the sealing lid 50, the energizing plate 33 and the first energizing plate 33 are provided. The space S12 between the second deformation plate 35 and the space S13 between the first deformation plate 31 and the energization plate 33 are in communication with each other. In the present embodiment, the three spaces (S11, S12, S13) separated from the space S3 inside the case 7 (hereinafter referred to as “third space S3”) by the first deformation plate 31 are referred to as “first”. This will be described as “1 space S1”.

  The cylindrical portion 53 is a cylindrical member having a hole portion 55, and extends upward from the central portion of the upper surface of the main body portion 51. The hole 55 communicates the first space S1 and the space S2 outside the case 7 (hereinafter referred to as “second space S2”). The cylindrical portion 53 is located inside the opening 73 </ b> A of the case 7. The current interrupt device 3 is fixed to the case 7 by a fixing member 61. As the fixing member 61, a nut that can be screwed into the male screw portion 53A can be used. The fixing member 61 is located outside the lid portion 73 of the case 7 in a state where the male screw portion 53A and the fixing member 61 are screwed together. The lid portion 73 of the case 7 is sandwiched between the main body portion 51 of the sealing lid body 50 located inside the case 7 and the fixing member 61 located outside the case 7. Thereby, the current interrupt device 3 is fixed to the case 7.

  The opening 73A of the case 7 and the side surface of the cylindrical portion 53 and the upper surface of the lid portion 73 of the case 7 and the fixing member 61 are insulated by a sleeve 63 having insulation properties. The sleeve 63 is a cylindrical member having a collar portion. The lower surface of the lid portion 73 of the case 7 and the upper surface of the main body portion 51 are insulated by the support member 41. Thereby, the sealing lid 50 and the case 7 are electrically insulated. The opening 73 </ b> A of the case 7 is hermetically closed by a seal member 65.

  In addition, a connecting portion 57 for connecting an external device (for example, another secondary battery or a motor) to the current interrupt device 3 is formed in the cylinder portion 53. The connection portion 57 has a mounting surface 53C and a female screw portion 53B.

  The attachment surface 53 </ b> C is formed on the upper end surface of the cylindrical portion 53. The hole part 55 in the cylinder part 53 has an opening part opened in the attachment surface 53C. A female screw part 53B is formed on the inner peripheral surface of the cylindrical part 53 forming the hole 55. A connection member 95 that supplies electric power to an external device (for example, another secondary battery or a motor) can be connected to the connection unit 57. Since the connection portion 57 is provided on the sealing lid body 50, the upper end portion of the cylindrical portion 53 of the sealing lid body 50 serves as the negative electrode terminal 87. In other words, the current interrupt device 3 and the negative electrode terminal 87 are integrally configured. A method for connecting the connecting portion 57 and the connecting member 95 will be described in detail later. In addition, the thread groove and the screw thread of the above-mentioned male thread part 53A and female thread part 53B are abbreviate | omitting illustration.

  The support member 41 has an insulating property, and is formed by, for example, a resin mold. When the support member 41 is viewed in plan, it has a ring shape. The cross section of the support member 41 is substantially U-shaped. The substantially U-shaped portion is provided with the outer peripheral portion of the first deformable plate 31, the outer peripheral portion of the energizing plate 33, the second deformable plate 35, and the outer peripheral portion of the sealing lid 50. 33, the second deformation plate 35 and the sealing lid 50 are integrated. The outer surface of the support member 41 is covered with a metal caulking member 42. The caulking member 42 reliably holds the member provided in the substantially U-shaped portion.

  Next, the energization path P will be described. The arrows shown in FIG. 3 indicate the energization path P from the electrode assembly 80 to the negative terminal 87. As described above, the energization plate 33 is electrically connected to the electrode assembly 80 (see FIG. 2) disposed inside the case 7. Further, the central portion of the energizing plate 33 is electrically connected to the second deformable plate 35, and the outer peripheral portion of the second deformable plate 35 is electrically connected to the sealing lid 50. Thereby, a series energization path P from the electrode assembly 80 to the negative electrode terminal 87 is formed.

  For example, when the secondary battery 1 is overcharged, gas is generated inside the sealed case 7 and the pressure inside the case 7 increases. In this case, as shown in FIG. 4, the pressure inside the case 7 acts on the first deformation plate 31, and the first deformation plate 31 is deformed (reversed) upward (on the current-carrying plate 33 side). When the first deformable plate 31 is deformed upward, the protrusion 43 collides with the energizing plate 33, the energizing plate 33 is broken starting from the breaking groove 33B, and a part of the energizing plate 33 is separated. Then, a part separated from the energization plate 33 comes into contact with the central portion of the second deformation plate 35, and the central portion of the second deformation plate 35 is deformed (reversed) upward (negative electrode terminal 87 side). As a result, the energization path P is broken and the current is interrupted. That is, the conduction between the negative terminal 87 and the electrode assembly 80 is interrupted. In other words, the current flow of the secondary battery 1 is interrupted.

  After the energization path P is ruptured, the projection 43 keeps a part separated from the energization plate 33 away from the energization plate 33, so that the energization path P is prevented from being easily formed again. The In other words, the energization path P is not formed (returned) again unless it is positively pressed by a bar-like member 93 described later. The first deformable plate 31 is not in contact with other components except that the outer peripheral portion is fixed to the support member 41. Therefore, the first deformation plate 31 is stably operated by the internal pressure of the case 7. Further, when the projection 43 provided on the first deformable plate 31 hits the energizing plate 33, an impact force is applied to the energizing plate 33.

  Importantly, when the internal pressure of the case 7 rises and the first deformable plate 31 is deformed upward, an impact is applied to the energizing plate 33 and a part of the energizing plate 33 is separated from the energizing plate 33, and This is to maintain a state in which the energizing plate 33 and the part separated from the energizing plate 33 after the energizing path P is broken are electrically insulated.

  Next, a method for connecting the connection portion 57 and the connection member 95 will be described. As shown in FIG. 5, first, a connection member 95 such as a bus bar is disposed on the mounting surface 53C. Next, the screw portion of the fastening member 91 such as a bolt is screwed into the female screw portion 53 </ b> B formed on the inner peripheral surface of the hole portion 55 of the sealing lid body 50. Then, the connection member 95 is sandwiched between the head of the fastening member 91 and the mounting surface 53C. Thereby, the connection member 95 is fixed to the negative electrode terminal 87. As shown in FIG. 5, the connection member 95 is a flat plate having conductivity. The connecting member 95 is formed with holes 95A and 95A through which the fastening member 91 is inserted.

  The fastening member 91 of the present embodiment is formed with a through hole (communication hole) 91A that penetrates the fastening member 91 along the axial direction. This through hole 91A communicates the first space S1 and the second space S2. And as shown in FIG. 3, the rod-shaped member 93 is inserted in the through-hole 91A of the fastening member 91. As shown in FIG. A gap is provided between the inner peripheral surface of the through hole 91 </ b> A and the outer peripheral surface of the rod-shaped member 93. In other words, communication between the first space S1 and the second space S2 is ensured even when the rod-like member 93 is inserted into the through hole 91A. In addition, a permeable film 91B that closes the through hole 91A is provided at the end of the through hole 91A on the second space S2 side.

  As shown in FIG. 3, the rod-shaped member 93 inserted into the through hole 91 </ b> A is provided before the current interrupting device 3 operates (normal time), that is, the first deformation plate 31 and the second deformation plate in the current interrupting device 3. Before 35 is deformed to the first space S1 side, the lower end is in contact with the second deformation plate 35, and the upper end is in contact with the film 91B. And as shown in FIG. 4, when the electric current interruption apparatus 3 act | operates, ie, the 1st deformation board 31 and the 2nd deformation board 35 in the electric current interruption apparatus 3 deform | transform into the 1st space S1 side, the lower end of the rod-shaped member 93 will be. Pushed upward, the upper end of the rod-like member 93 breaks the membrane 91B and protrudes from the through hole 91A. Moreover, the deformed second deformable plate 35 can be returned to the state before being deformed by pressing the rod-shaped member 93 protruding from the through hole 91A toward the inside of the case 7.

  In the secondary battery 1 having the configuration described above, the first space S1 that is isolated from the third space S3 and is formed between the second deformable plate 35 and the negative electrode terminal 87 (sealing lid body 50), and the case 7 is in communication with the second space S2, which is an external space. For this reason, the first space S1 is held at the pressure of the second space S2. As a result, it is easy to keep the pressure in the first space S1 to which the surface of the first deformable plate 31 opposite to the pressure receiving surface 31A inside the case 7 is exposed constant. For this reason, when the pressure in the third space S3 increases due to overcharging or the like, a pressure difference between the first space S1 and the third space S3 is likely to be generated. As a result, in the case of overcharge or the like, it is possible to prevent the current interrupt device 3 from malfunctioning due to a lack of the pressure difference between the first space S1 and the third space S3. That is, the operating pressure accuracy in the current interrupt device 3 can be improved.

  Since the secondary battery 1 of the above embodiment includes the linear rod-like member 93 inserted into the through hole 91A, it is only necessary to confirm the height position (protrusion degree) of the rod-like member 93 in the through hole 91A. The presence or absence of operation in the current interrupting device 3 can be easily confirmed. Moreover, the electric current interruption apparatus 3 can be returned only by pushing down this rod-shaped member 93 below.

  In the secondary battery 1 of the above embodiment, a permeable film 91B that closes the through hole 91A is provided at the end of the through hole 91A on the second space S2 side. Thereby, it can prevent that a foreign material penetrate | invades in 91 A of through-holes, ensuring the gas flow (communication) of 1st space S1 and 2nd space S2.

  In the battery module of the above embodiment, the through hole 91 </ b> A penetrating in the axial direction is provided in the fastening member 91 that is inserted into the hole 55 of the sealing lid 50. For this reason, the pressure of 1st space S1 can be open | released to 2nd space S2 irrespective of the penetration state of the fastening member 91. FIG. As a result, in the case of overcharge or the like, it is possible to prevent the current interrupting device 3 from malfunctioning due to a shortage of the pressure difference between the third space S3 and the first space S1. That is, the operating pressure accuracy in the current interrupt device 3 can be improved.

  Although one embodiment has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.

  In the secondary battery 1 of the above-described embodiment, the example in which the hole 55 for inserting the fastening member 91 for fastening the connection member 95 to the sealing lid 50 is formed has been described. The present invention is not limited to this. For example, as shown in FIG. 6, in the case of a battery module configured such that the sealing lid 150 and the connection member 95 are connected by welding or the like, the above-described hole is provided in the cylindrical portion 153 of the sealing lid 150. Absent. In this case, a communication hole for communicating the first space S1 and the second space S2 may be provided somewhere on the sealing lid 50.

  For example, as shown in FIG. 6, a communication hole 155 that penetrates from the lower surface to the upper surface of the main body 151 is provided in the main body 151 of the sealing lid 150, and the communication hole 155 and the second space S <b> 2 are connected to the sleeve 63. A slit 63A is formed. The slit 63A of the sleeve 63 is formed, for example, along the axial direction in the cylindrical portion and along the radial direction in the collar portion, thereby connecting the communication hole 155 of the sealing lid 150 and the second space S2. Can be connected. Even in this case, the same effects as the secondary battery 1 of the above embodiment can be enjoyed.

  The secondary battery 1 of the above embodiment includes the first deformation plate 31 that deforms when the pressure inside the case 7 exceeds a predetermined level, and the second deformation plate 35 that deforms in conjunction with the first deformation plate 31. The configuration has been described as an example. The present invention is not limited to this. For example, as shown in FIGS. 7 and 8, only the first deformable plate 31 that deforms when the pressure inside the case 7 rises above a predetermined level is provided. The secondary battery may be configured such that the fragile portion (region surrounded by the fracture groove 33B) is destroyed. Even in this case, the same effects as the secondary battery 1 of the above embodiment can be enjoyed.

  Further, as shown in FIG. 7, the rod-like member 93 inserted into the through hole 91 </ b> A has a lower end that is second deformed before the second deformable plate 35 in the current interrupting device 3 is deformed to the first space S <b> 1 side. It contacts the plate 35 and the upper end is in contact with the film 91B. Then, as shown in FIG. 8, when the second deformation plate 35 in the current interrupting device 3 is deformed to the first space S1, the lower end of the rod-shaped member 93 is pushed upward, and the upper end of the rod-shaped member 93 breaks the film 91B. Projecting from the through hole 91A. Moreover, the deformed second deformable plate 35 can be returned to the state before being deformed by pressing the rod-shaped member 93 protruding from the through hole 91A toward the inside of the case 7.

  In the secondary battery 1 of the above embodiment, the configuration including the rod-shaped member 93 inserted into the through hole 91A has been described as an example, but the present invention is not limited to this. The rod-shaped member 93 may not be provided as a product. Even in this case, if there is only a bar-like member that can penetrate through the through hole 91A, the second deformable plate 35 can be returned to the state before the deformation by inserting and pressing the bar-like member into the through hole. . That is, in the case of a fastening member without the through hole 91A, it is necessary to remove the fastening member from the hole 55 and return the second deformable plate 35. However, in the secondary battery of this configuration, the labor can be saved. it can. This effect is common to the above-described embodiments.

  In addition, for example, a wound electrode assembly may be used instead of the stacked electrode assembly 80. The wound-type electrode assembly is manufactured by winding a belt-like positive electrode, a belt-like negative electrode, and a belt-like separator around an axis in a stacked state.

  As the power storage device, in addition to the secondary battery 1, for example, an electric double layer capacitor and the like can be given.

  The power storage device such as the secondary battery 1 may be mounted on a vehicle, for example. Examples of the vehicle include, for example, an electric vehicle, a hybrid vehicle, a plug-in hybrid vehicle, a hybrid railway vehicle, an electric wheelchair, an electrically assisted bicycle, and an electric motorcycle.

  DESCRIPTION OF SYMBOLS 1 ... Secondary battery (electric storage apparatus), 3 ... Current interruption device, 7 ... Case, 31 ... 1st deformation plate (deformation plate), 31A ... Pressure receiving surface, 33 ... Current supply plate, 33B ... Breaking groove, 35 ... 2nd Deformation plate (deformation plate), 50 ... sealing lid, 53C ... mounting surface, 55 ... hole, 57 ... connection part, 61 ... fixing member, 80 ... electrode assembly, 87 ... negative electrode terminal, 89 ... positive electrode terminal, 91 ... Fastening member, 91A ... Through hole, 91B ... Membrane, 93 ... Rod-like member, 95 ... Connection member, 100 ... Battery module (power storage module), 150 ... Sealing lid, 155 ... Communication hole, P ... Current path, S1 ... 1st space, S2 ... 2nd space, S3 ... 3rd space.

Claims (8)

An electrode assembly in which a positive electrode and a negative electrode are laminated via a separator;
A case for housing the electrode assembly;
A positive electrode terminal and a negative electrode terminal provided so as to protrude from the case;
Provided between at least one of the electrode assembly and the positive electrode terminal and between the electrode assembly and the negative electrode terminal to electrically connect the electrode assembly and the positive electrode terminal or the negative electrode terminal. And a current interrupting device that interrupts an energization path between the electrode assembly and the positive terminal or the negative terminal by a deforming plate that deforms when the pressure inside the case rises above a predetermined level. ,
The positive electrode terminal and the negative electrode terminal connected to the current interrupt device are separated from the space inside the case by the deformation plate and are a space between the deformation plate and the positive electrode terminal or the negative electrode terminal. The electrical storage apparatus provided with the communicating hole which connects 1 space and the 2nd space which is the space outside the said case.   The power storage device according to claim 1, wherein the communication hole is formed in a linear shape, and the deformation plate is positioned on an extension line of the axis of the communication hole.   The power storage device according to claim 2, wherein a portion where the energization path is blocked by the deformation plate is located on an extension line of the axis of the communication hole. A linear rod-like member inserted in the communication hole;
The power storage device according to any one of claims 1 to 3, wherein one end portion of the rod-shaped member is disposed in contact with the deformation plate.   5. The power storage device according to claim 1, wherein a permeable film that closes the communication hole is provided at an end of the communication hole on the second space side.   The power storage device according to any one of claims 1 to 5, wherein the power storage device is a secondary battery.   The electrical storage module provided with two or more electrical storage apparatuses as described in any one of Claims 1-6, and these electrical storage apparatuses are electrically connected by the connection member. The positive electrode terminal and the negative electrode terminal to which the current interrupting device is connected communicate with the first space and have a hole for penetrating a fastening member for fastening the connection member to the positive electrode terminal or the negative electrode terminal. Have
The connection member is fastened to the positive electrode terminal or the negative electrode terminal by the fastening member penetrated into the hole,
The fastening member has a through hole penetrating in the axial direction, and the communication hole is formed by the through hole.
The power storage module according to claim 7.

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