JP2005332608A - Secondary battery, battery pack, composite battery pack and vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a secondary battery having high electrical insulation properties between a metallic electrode terminal or a metallic current collector and a metallic layer of an outer jacket member. <P>SOLUTION: The secondary battery 10 is equipped with an electrode laminated body 101 formed by alternately laminating a positive electrode plate 102 in which positive electrode layers 102b, 102c are formed on a positive current collector 102a, a negative electrode plate 104 in which negative electrode layers 104b, 104c are formed on a negative current collector 104a through a separator 103, outer jacket members 107, 108 having inside resin layers 107a, 108b, intermediate metallic layers 107b, 108b, and outside resin layers 107c, 108c, and housing and sealing the electrode laminated body 101, and electrode terminals 105, 106 connected to the current collectors 102a, 104a extending from the electrode laminated body 101 and introduced from outer peripheries of the outer jacket members 106, 107, first and second protection means 121, 122 covering corners of the electrode laminated body 101, and third and fourth protection members 123, 124 covering connecting parts 111, 112 of the current collectors 102a, 104a with the electrode terminals 105, 106. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a secondary battery in which electrode plates stacked via a separator are accommodated in an exterior member and sealed, and electrode terminals connected to the electrode plates are led out from an outer peripheral edge of the exterior member.

  An exterior composed of an electrode laminate formed by laminating electrode plates with electrode layers formed on both main surfaces of a current collector via a separator, and a metal layer sandwiched between two synthetic resin layers There is known a thin secondary battery that is housed in a member and sealed, and electrode terminals connected to a current collector extending from the electrode laminate are led out from an outer peripheral edge of the exterior member.

  In such a secondary battery, since the electrode terminal and the current collector are made of a metal thin film, the corners and burrs of the metal thin film penetrate the synthetic resin layer inside the exterior member, In some cases, a short circuit may occur between the metal electrode terminal or current collector and the metal layer of the exterior member, or the insulation distance may be reduced.

An object of the present invention is to provide a secondary battery excellent in electrical insulation between a metal electrode terminal or current collector and a metal layer of an exterior member.
In order to achieve the above object, according to the present invention, an electrode laminate in which an electrode plate having an electrode layer formed on a current collector is laminated via a separator, a metal layer, and a laminate inside the metal layer. An exterior member having at least a synthetic resin layer formed and containing and sealing the electrode laminate, and connected to the current collector extending from the electrode laminate, from an outer periphery of the exterior member A secondary battery comprising a lead electrode terminal, and further comprising protection means for covering each of the connection part between the current collector and the electrode terminal and the corner part of the electrode laminate. A secondary battery is provided.

  In the secondary battery according to the present invention, the connecting portion between the current collector and the electrode terminal and the corner portion of the electrode laminate are respectively covered by the protection means. This protective means covers the current collector made of a metal material, and the projections such as the corners and burrs of the electrode terminals, so that the projections can be prevented from penetrating the synthetic resin layer inside the exterior member. This makes it possible to ensure excellent electrical insulation between the metal electrode terminal or current collector and the metal layer of the exterior member.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a plan view showing an entire secondary battery according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the secondary battery taken along line II-II in FIG. 1, and FIG. 3 is a line III-III in FIG. FIG. 4 is a diagram showing a mass-spring system model in the positive electrode side connection portion of FIG. 3, and FIG. 5 is a vibration transmissibility in the positive electrode side connection portion according to the embodiment of the present invention. It is a graph which shows a spectrum.

  1 and 2 show one secondary battery (unit battery), and a plurality of secondary batteries 10 are stacked and connected to form an assembled battery having a desired voltage and capacity.

  First, a secondary battery 10 according to an embodiment of the present invention will be described. The secondary battery 10 is a lithium-based thin secondary battery, and includes three positive electrode plates as shown in FIGS. 1 and 2. 102, an electrode laminate 101 having five separators 103 and three negative plates 104, a positive electrode terminal 105 and a negative electrode terminal 106 respectively connected to the electrode laminate 101, and the electrode laminate 101 and electrodes. It comprises an upper exterior member 107 and a lower exterior member 108 that house and seal the terminals 105 and 106, and an electrolyte (not shown).

  As shown in FIG. 2, the three positive electrode plates 102 constituting the electrode laminate 101 include a positive electrode side current collector 102a extending to the positive electrode terminal 105 and a part of both main electrodes of the positive electrode side current collector 102a. It has positive electrode layers 102b and 102c formed on the surface, respectively.

  The positive electrode side current collector 102 a of the positive electrode plate 102 is an electrochemically stable metal foil such as an aluminum foil, an aluminum alloy foil, a copper foil, or a nickel foil having a thickness of about 20 μm.

The positive electrode layers 102b and 102c of the positive electrode plate 102 are formed by mixing a positive electrode active material such as a metal oxide, a conductive agent such as carbon black, and an adhesive such as an aqueous dispersion of polytetrafluoroethylene. Is applied to a part of the main surface of the positive electrode side current collector 102a, dried and rolled. Examples of the positive electrode active material include lithium-based composite oxides such as lithium nickelate (LiNiO ₂ ), lithium manganate (LiMnO ₂ ), or lithium cobaltate (LiCoO ₂ ), and chalcogens (S, Se, Te). A compound etc. can be mentioned.

  As shown in FIG. 2, the three negative electrode plates 104 constituting the electrode laminate 101 include a negative electrode current collector 104a extending to the negative electrode terminal 106, and both main parts of the negative electrode current collector 104a. And negative electrode layers 104b and 104c respectively formed on the surface.

  The negative electrode side current collector 104a of the negative electrode plate 104 is an electrochemically stable metal foil such as a nickel foil, a copper foil, a stainless steel foil, or an iron foil having a thickness of about 10 μm.

  The negative electrode layers 104b and 104c of the negative electrode plate 104 occlude and release lithium ions of the positive electrode active material such as amorphous carbon, non-graphitizable carbon, graphitizable carbon, or graphite. A mixture of an aqueous dispersion of styrene butadiene rubber resin powder as a precursor material of an organic fired body mixed with a negative electrode active material, dried, and pulverized to carry carbonized styrene butadiene rubber on the surface of carbon particles Is formed by applying a negative electrode mixture in which a binder such as an acrylic resin emulsion is further mixed to both main surfaces of a part of the negative electrode current collector 104a, and drying and rolling. Yes.

  The five separators 103 of the electrode laminate 101 prevent the short circuit between the positive electrode plate 102 and the negative electrode plate 104 described above, and may have a function of holding an electrolyte. The separator 103 is a microporous film made of, for example, a polyolefin such as polyethylene (PE) or polypropylene (PP) having a thickness of about 25 μm. When an overcurrent flows, the separator 103 generates pores due to heat generation. Has a function of blocking the current.

  The separator of the present invention is not limited to a single-layer film such as polyolefin, but may be a three-layer structure in which a polypropylene film is sandwiched with a polyethylene film, or a laminate of a polyolefin microporous film and an organic nonwoven fabric or the like. . By forming the separator in multiple layers, various functions such as an overcurrent prevention function, an electrolyte holding function, and a separator shape maintenance (rigidity improvement) function can be provided.

  The electrode laminate 101 is configured by alternately laminating the positive electrode plates 102 and the negative electrode plates 104 with the separators 103 interposed therebetween. In the present embodiment, as shown in FIGS. A first protective member 121 is laminated on the upper surface of the electrode laminate 101.

  As shown in the figure, the first protective member 121 is made of a synthetic resin film having a size capable of covering the entire top surface of the electrode laminate 101. Each corner portion of the positive electrode side current collector 102 a located in the uppermost layer is covered to prevent the corner portion from penetrating the inner resin layers 107 a and 108 a of the exterior members 107 and 108.

  Similarly, as shown in FIGS. 1 and 2, the second protective member 122 is laminated on the lower surface of the electrode laminate 101. The second protective member 122 is a synthetic resin film or the like having a size capable of covering the entire lower surface of the electrode laminate 101, and in particular, the negative electrode side collector located in the lowermost layer of the electrode laminate 101. Each corner portion of the electric body 104a is covered to prevent the corner portion from penetrating the inner resin layers 107a and 108a of the exterior members 107 and 108.

  Examples of the synthetic resin material constituting the first and second protective members 121 and 122 include an olefin resin such as polyethylene and polypropylene, an epoxy resin, and a urethane resin having a Shore A hardness of about 5 to 95. Resin or nylon resin can be used. In addition, JIS-A hardness said by this invention refers to the physical-property value measured based on JIS specification K-6301.

  When the JIS-A hardness of the first and second protective members 121 and 122 is less than 5, the corners of the electrode laminate 101 are too soft to protect. On the other hand, when the JIS-A hardness of the first and second protective members 121 and 122 is greater than 95, the first and second protective members 121 and 122 become too hard, and the corners of the electrode laminate 101 are formed. There is a risk of passing through the first and second protective members 121 and 122.

  The three positive electrode plates 102 laminated on the electrode laminate 101 are connected to the positive electrode terminal 105 made of metal foil via the positive electrode current collector 102a at the positive electrode side connection portion 111, while the electrode laminate The three negative plates 104 laminated on 101 are similarly connected to the negative electrode terminal 106 made of metal foil through the negative electrode side current collector 104a at the negative electrode side connection portion 112.

  Note that the positive electrode plate 102, the separator 103, and the negative electrode plate 104 constituting the electrode laminate 101 are not limited to the above number in the present invention. For example, each of the positive electrode plate, the separator, and the negative electrode plate may be an electrode. A laminated body can be comprised, and it can comprise by selecting the number of a positive electrode plate, a separator, and a negative electrode plate as needed. In this embodiment, the electrode plates 102 and 104 are connected to the electrode terminals 105 and 106 by extending the metal foil itself constituting the current collectors 102 a and 104 a of the electrode plates 102 and 104 to the electrode terminals 105 and 106. The current collectors 102a and 104a of the electrode plates 102 and 104 and the electrode terminals 105 and 106 are separated from the metal foil constituting the current collectors 102a and 104a. You may connect with material and components.

  The positive electrode terminal 105 and the negative electrode terminal 106 are not particularly limited as long as they are electrochemically stable metal foils. Examples of the positive electrode terminal 105 include an aluminum foil having a thickness of about 0.2 mm, an aluminum alloy foil, a copper foil, or And nickel foil. Examples of the negative electrode terminal 106 include a nickel foil, a copper foil, a stainless steel foil, or an iron foil having a thickness of about 0.2 mm.

  A positive current collector 102 a extending from each positive electrode plate 102 of the electrode laminate 101 is connected to the positive electrode terminal 105 by a positive electrode side connection portion 111 by a technique such as ultrasonic welding, spot welding, or cold welding. However, in the secondary battery 10 according to the present embodiment, as shown in FIGS. 1 and 2, the positive electrode side connecting portion 111 is entirely formed by the third protective member 123 formed of a synthetic resin film. Covering, the corners of the positive electrode terminal 105 and the positive electrode side current collector 102a and protrusions such as burrs are prevented from penetrating the inner resin layers 107a and 108a of the exterior members 107 and 108.

  Similarly, as shown in FIGS. 1 and 3, a fourth protective member in which the entire negative electrode side connecting portion 112 to which the negative electrode terminal 106 and the negative electrode side current collector 104 a are connected is made of a synthetic resin film. 124 to prevent the corners of the negative electrode terminal 106 and the negative electrode current collector 104a and protrusions such as burrs from penetrating into the inner resin layers 107a and 108a of the exterior members 107 and 108.

  As the synthetic resin material constituting these third and fourth protective members 123 and 124, JIS-A hardness is about 5 to 95, for example, olefin resin such as polyethylene and polypropylene, epoxy resin and urethane resin. Resin or nylon resin can be used.

  When the JIS-A hardness of the third and fourth protection members 123 and 124 is less than 5, the corners and burrs of the current collectors 102a and 104a are too soft to protect. On the other hand, when the JIS-A hardness of the third and fourth protective members 123 and 124 is greater than 95, the third and fourth protective members 123 and 124 become too hard and the corners of the current collectors 102a and 104a are increased. There is a possibility that protrusions such as burrs and burrs may penetrate the third and fourth protective members 123 and 124.

  Furthermore, in the secondary battery 10 according to the present embodiment, the third protective member 123 has 50 to 50 Young's modulus of the synthetic resin material (described later) constituting the inner resin layers 107a and 108a of the exterior members 107 and 108. It has a Young's modulus of about 100%.

  As shown in FIG. 3, the third protective member 123 covers the positive current collector 102 a and the positive terminal 105 in the positive electrode side connecting portion 111, and covers the upper exterior member 107 and the upper exterior member 108. A mass-spring system model that is covered and can shift the resonance frequency in the positive electrode side connecting portion 111 as shown in FIG. 4 because the third protective member 123 has the Young's modulus as described above. Is forming.

  In the mass-spring system model shown in FIG. 4, the intermediate metal layer 107b of the upper exterior member 107 corresponds to the first mass portion M1, and the positive terminal 105 corresponds to the second mass portion M2. Further, the third protective member 123a interposed between the positive electrode current collector 102a and the upper exterior member 107 in FIG. 3 corresponds to the first spring portion K1 and the first damping element C1 shown in FIG. The third protective member 123b interposed between the positive electrode terminal 105 and the lower exterior member 108 in FIG. 3 corresponds to the second spring portion K2 and the second damping element C2 shown in FIG.

  In the secondary battery 10 according to the present embodiment, the Young's modulus of the third protective member 123 is set to about 50 to 100% of the Young's modulus of the inner resin layers 107a and 108a of the exterior members 107 and 108, and the positive electrode side connection portion. By constructing a mass-spring system model as shown in FIG. 4 in 111, the secondary vibration systems M1, K1, and C1 act like dynamic vibration absorbers on the main vibration systems M2, K2, and C2, and the positive electrode It is possible to shift the resonance frequency of the side connection portion 111.

  When the Young's modulus of the third protective member 123 is greater than 100% with respect to the Young's modulus of the exterior members 107 and 108, the third protective members 123a and 123b cause the spring portions K1 and K2 and the damping elements C1 and C2 to move. Since it is not configured, the mass-spring system model shown in FIG. 4 is not established, and it is difficult to shift the resonance frequency of the positive electrode side connecting portion 111. On the other hand, if the Young's modulus of the third protective member 123 is less than 50% with respect to the Young's modulus of the exterior members 107 and 108, the structure of the positive electrode side connecting portion 111 may be weak.

  Then, by changing the material and thickness of the third protective member 123, the positive electrode terminal 105, and the intermediate metal layer 107b, the primary natural frequency and the secondary natural frequency in the mass-spring system model of the positive electrode side connecting portion 111 are changed. By performing tuning, the resonance frequency can be appropriately separated from the excitation frequency.

  For example, FIG. 5 shows the vibration at the positive electrode side connection portion of the secondary battery according to the present embodiment, with the vibration transmissibility that is the ratio of the excitation amplitude and the response amplitude as the vertical axis and the corresponding frequency as the horizontal axis. Although it is a graph which shows a transmissibility spectrum, as shown in the figure, for example, in the case where a secondary battery is used in a vehicle in which the excitation frequency is particularly concentrated to about 100 Hz or less, the resonance frequency of the positive electrode side connecting portion 111 Is separated from the excitation frequency by shifting to a frequency of about 100 Hz or more, thereby preventing peeling or the like that occurs between the positive electrode terminal 105 and the positive electrode current collector 102a at the positive electrode side connection portion 111 due to vibration applied when the vehicle is used. It is possible to improve the vibration reliability of the positive electrode side connecting portion 111. In FIG. 5, the solid line graph indicates the vibration transmissibility spectrum at the positive electrode side connection part of the secondary battery according to the present embodiment having the third and fourth protection members 123 and 124, and the broken line graph indicates the first 3 shows a vibration transmissibility spectrum at the positive electrode side connecting portion of a secondary battery having a conventional structure that does not include the third and fourth protective members 123 and 124.

  Similarly, the fourth protective member 124 has a Young's modulus of about 50 to 100% with respect to the Young's modulus of the synthetic resin material constituting the inner resin layers 107a and 108a of the exterior members 107 and 108, although not particularly shown. A mass-spring system model capable of shifting the resonance frequency, similar to that shown in FIG. 4, is formed in the negative electrode side connection portion 112, and the fourth protective member 124, the negative electrode terminal 106, or the middle By tuning the primary natural frequency and the secondary natural frequency in the mass-spring system model of the negative electrode side connection part 112 by changing the material and thickness of the metal layer 107b, the resonance frequency is changed from the excitation frequency. It is possible to be separated appropriately.

  As shown in FIG. 2, the electrode laminate 101 configured as described above includes an upper exterior member 107 having a cup-shaped outer shape provided with a convex portion, and a lower exterior member 108 having a flat outer shape. And sealed.

  As shown in FIG. 3, the upper exterior member 107 is an inner side made of, for example, a resin film excellent in an electrolytic solution and heat fusion properties such as polyethylene, modified polyethylene, polypropylene, modified polypropylene, or ionomer. Resin layer 107a, intermediate metal layer 107b composed of a metal foil such as aluminum foil, and outer resin composed of a resin film excellent in electrical insulation such as a polyamide resin and a polyester resin It has a three-layer structure including the layer 107c.

  Similarly, as shown in FIG. 3, the lower exterior member 108 is also made of, for example, a resin film excellent in electrolytic resistance and heat-fusibility such as polyethylene, modified polyethylene, polypropylene, modified polypropylene, or ionomer. The inner resin layer 108a, an intermediate metal layer 108b made of a metal foil such as an aluminum foil, and a resin film excellent in electrical insulation such as a polyamide resin or a polyester resin. It has a three-layer structure with the outer resin layer 108c.

  Therefore, the upper exterior member 107 and the lower exterior member 108 are formed by laminating one surface of the metal foil (the inner surface of the secondary battery 10) with a resin film such as polyethylene and the other surface (the outer surface of the secondary battery 10). ) With a resin film such as a polyamide-based resin, for example, a flexible resin-metal thin film laminate material having a thickness of about 125 μm.

  In the present embodiment, the seal film 109 is interposed between the positive electrode terminal 105 and the exterior members 107 and 108, and the seal film 109 is also interposed between the negative electrode terminal 106 and the exterior members 107 and 108. The sealing property of the secondary battery 10 is improved.

  As the synthetic resin material constituting the seal film 109, as in the case of the inner resin layers 107a and 108a of the exterior members 107 and 108, for example, an electrolytic resistant solution such as polyethylene, modified polyethylene, polypropylene, modified polypropylene, or ionomer, and the like A synthetic resin material excellent in heat-fusibility can be mentioned.

  In the present invention, the number of layers constituting the exterior member is not limited to the above, and the number of layers can be appropriately set as necessary. Further, in the present embodiment, the upper exterior member 107 and the flat lower exterior member 108 which are preliminarily formed in a cup shape are used as the exterior members. You may use what was shape | molded for an upper exterior member and a lower exterior member. Further, in the present embodiment, the seal film 109 is interposed between the exterior members 107 and 108 and the electrode terminals 105 and 106. However, in the present invention, the present invention is not particularly limited thereto, and the inner resin layer of the exterior member is provided. You may heat-seal directly to an electrode terminal. Further, in the present embodiment, as shown in FIG. 1, the positive electrode terminal 105 and the negative electrode terminal 106 are led out from the opposing short sides of the exterior members 107 and 108 of the secondary battery 10, respectively. For example, the positive electrode terminal and the negative electrode terminal may be led out in the same direction from the same short side of the exterior member.

The above-described exterior members 107 and 108 enclose the electrode laminate 101 and part of the electrode terminals 105 and 106, and inject the liquid electrolyte into the space formed by the exterior members 107 and 108, while After vacuuming the interior, the exterior members 107 and 108 are heat-sealed at their outer peripheral edges and sealed. Examples of the solute of the liquid electrolyte include lithium salts such as lithium hexafluorophosphate (LiPF ₆ ), lithium perchlorate (LiClO ₄ ), and lithium borofluoride (LiBF ₄ ). Examples of the organic liquid solvent for the liquid electrolyte include ester solvents such as propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DEC), methyl ethyl carbonate (MEC), and dimethyl carbonate (DMC). However, the organic liquid solvent of the present invention is not particularly limited thereto, and is an organic liquid solvent prepared by mixing an ester solvent with an ether solvent such as γ-butylactone (γ-BL) or dietoshietane (DEE) and the like. Can also be used.

  Below, the assembled battery comprised by combining multiple said secondary batteries and the composite assembled battery comprised by combining multiple said assembled batteries are demonstrated.

  6 (A) to 6 (C) are views showing the assembled battery according to the embodiment of the present invention, FIG. 6 (A) is a plan view thereof, FIG. 6 (B) is a front view thereof, and FIG. 6 (C). Is a side view, FIG. 7 is a perspective view of a composite battery according to an embodiment of the present invention, FIG. 8A is a plan view of the composite battery shown in FIG. 7, and FIG. 8B is a composite shown in FIG. FIG. 8C is a side view of the composite assembled battery shown in FIG. 7, and FIG. 9 is a schematic view of the composite assembled battery according to the embodiment of the present invention mounted on a vehicle.

  FIGS. 6A to 6C show an assembled battery 20 configured by connecting 24 secondary batteries 10 described above. As shown in FIGS. 6A to 6C, the assembled battery 20 according to the present embodiment includes 24 secondary batteries 10, assembled battery electrode terminals 22 and 23, and a housing 25. 24 secondary batteries 10 are connected in parallel.

  As shown in FIG. 6A, the electrode terminals 105 and 106 of the respective secondary batteries 10 are connected in parallel by bus bars 21a and 21b. The positive-side bus bar 21 a connecting each positive terminal 105 is connected to the assembled battery positive terminal 22, and the negative-side bus bar 21 b connecting each negative terminal 106 is connected to the assembled battery negative terminal 23. Has been.

  The 24 secondary batteries 10 electrically connected in this way are accommodated in the housing 25 filled with the filler 24 while the assembled battery electrode terminals 22 and 23 are led out of the housing 25. Has been sealed. In addition, shock absorbers 26 are attached to the four corners of the lower surface of the casing 25, so that transmission of vibrations can be reduced as much as possible when the assembled batteries 20 are stacked as a composite assembled battery described later. .

  7 and 8A to 8C show a composite assembled battery 30 configured by connecting six assembled batteries 20 described above. The composite battery pack 30 according to this embodiment includes six battery packs 20, external electrode terminals 31 and 32, and a connecting member 34.

  First, as shown in FIGS. 7 and 8A to 8C, the six assembled batteries 20 of the composite assembled battery 30 have the assembled battery electrode terminals 22 and 23 in the same direction. It is laminated so as to lead to That is, the assembled battery electrode terminals 22 and 23 of the assembled battery 20 located at the m-th stage and the assembled battery electrode terminals 22 and 23 of the assembled battery 20 located at the (m + 1) -th stage are led out in the same direction. The m + 1 stage assembled battery 20 is stacked on the m stage assembled battery 20 (where m is a natural number of 1 to 5).

  As shown in the drawing, the external electrode terminals 31 and 32 of the composite battery pack 30 have a substantially rectangular flat plate shape, and have a plurality of diameters into which the battery pack electrode terminals 22 and 23 can be inserted or press-fitted. 6 holes for connecting the terminals are respectively machined. The holes are processed at a pitch substantially equal to the pitch between the assembled battery homopolar terminals 22 and 23 of the assembled batteries 20 when stacked. All the assembled battery positive terminals 22 facing in the same direction in the stacked assembled battery 20 are inserted or press-fitted into the respective holes of the external positive terminal 31, and are stacked in the respective holes of the external negative terminal 32. In the assembled battery 20, all the assembled battery negative terminals 23 facing in the same direction are inserted or press-fitted, and the six assembled batteries 20 are connected in parallel by the external electrode terminals 31 and 32.

  The six battery packs 20 electrically connected in this way have flat connecting members 34 attached to both side portions thereof, and are fixed by fixing screws 35.

  As described above, an assembled battery is configured with a predetermined number of secondary batteries as a unit, and a combined battery is configured with the assembled battery as a unit, so that the assembled battery is adapted to the required capacity, voltage, etc. It becomes possible to easily obtain a composite assembled battery. In addition, since the composite assembled battery can be configured without complicated connection, the failure rate of the composite assembled battery due to poor connection or the like can be reduced. Further, when some of the secondary batteries constituting the composite battery pack need to be replaced due to failure or deterioration, the composite battery pack is replaced by replacing only the battery pack incorporating the failed secondary battery. Can be easily repaired.

  FIG. 9 is a schematic diagram illustrating an example in which the above-described composite assembled battery 30 is mounted under the floor of the vehicle 1 such as an electric vehicle. It is particularly effective to use an assembled battery or a composite assembled battery having a low failure rate and excellent replaceability as described above for a vehicle such as an electric vehicle to which a relatively large amount of vibration is applied from the outside.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, in the above-described embodiment, the assembled battery is configured by connecting 24 secondary batteries in parallel. However, the present invention is not particularly limited to this, and any number may be used depending on the required capacity and voltage. Secondary batteries may be connected in parallel, or any number of secondary batteries may be connected in series or in parallel-series combination. Further, in the above-described embodiment, a composite assembled battery is configured by connecting six assembled batteries in parallel. However, the present invention is not particularly limited to this, and an arbitrary number is set according to the required capacity and voltage. These battery packs may be connected in parallel, or any number of battery packs may be connected in series or in parallel and in series.

FIG. 1 is a plan view showing an entire secondary battery according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the secondary battery taken along line II-II in FIG. FIG. 3 is a cross-sectional view of the positive electrode side connecting portion taken along line III-III in FIG. FIG. 4 is a diagram illustrating a mass-spring system model in the positive electrode side connection portion of FIG. 3. FIG. 5 is a graph showing a vibration transmissibility spectrum in the positive electrode side connection portion according to the embodiment of the present invention. 6 (A) to 6 (C) are diagrams showing an assembled battery according to an embodiment of the present invention, FIG. 6 (A) is a plan view thereof, and FIG. 6 (B) is a front view thereof. FIG. 6C is a side view thereof. FIG. 7 is a perspective view of the composite battery pack according to the embodiment of the present invention. 8A is a plan view of the composite assembled battery shown in FIG. 7, FIG. 8B is a front view of the composite assembled battery shown in FIG. 7, and FIG. It is a side view of the composite assembled battery shown. FIG. 9 is a schematic view in which the composite battery pack according to the embodiment of the present invention is mounted on a vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle 10 ... Secondary battery 101 ... Electrode laminated body 102 ... Positive electrode plate 102a ... Positive electrode side collector 102b, 102c ... Positive electrode layer 103 ... Separator 104 ... Negative electrode plate 104a ... Negative electrode side collector 104b, 104c ... Negative electrode layer DESCRIPTION OF SYMBOLS 105 ... Positive electrode terminal 106 ... Negative electrode terminal 107 ... Upper exterior member 107a ... Inner resin layer 107b ... Metal layer 107c ... Outer resin layer 108 ... Lower exterior member 108a ... Inner resin layer 108b ... Metal layer 108c ... Outer resin layer 109 ... Seal film DESCRIPTION OF SYMBOLS 111 ... Positive electrode side connection part 112 ... Negative electrode side connection part 121-124 ... The 1st-4th protective member 20 ... Assembly battery 30 ... Composite assembled battery

Claims (10)

An electrode laminate in which an electrode plate having an electrode layer formed on a current collector is laminated via a separator;
A metal layer, and an exterior member having at least a synthetic resin layer laminated on the inner side of the metal layer and containing and sealing the electrode laminate;
An electrode terminal connected to the current collector extending from the electrode laminate and led out from an outer peripheral edge of the exterior member, and a secondary battery comprising:
The secondary battery further provided with the protection means which each covers the connection part of the said electrical power collector and the said electrode terminal, and the corner | angular part of the said electrode laminated body.   The secondary battery according to claim 1, wherein the protection means is made of a material including a synthetic resin material.   The secondary battery according to claim 1 or 2, wherein the synthetic resin material included in the material constituting the protection means has a Young's modulus of 50 to 100% with respect to the Young's modulus of the synthetic resin layer of the exterior member. .   The secondary battery according to any one of claims 1 to 3, wherein a JIS-A hardness of the synthetic resin material included in the material constituting the protection means is 5 to 95.   The synthetic resin material contained in the material constituting the protection means includes one or more components selected from the group consisting of olefin resins, epoxy resins, urethane resins, or nylon resins. The secondary battery in any one of -4.   The said electrode plate contains the positive electrode plate which has a positive electrode active material which consists of lithium-manganese complex oxide, lithium-nickel complex oxide, or lithium-cobalt complex oxide in any one of Claims 1-5. The assembled battery as described.   The assembled battery according to claim 1, wherein the electrode plate includes a negative electrode plate having a negative electrode active material made of a crystalline carbon material or an amorphous carbon material. An assembled battery comprising a plurality of the secondary batteries according to claim 1,
An assembled battery including at least two or more secondary batteries in which one of the secondary batteries and the other secondary battery are electrically connected in series and / or in parallel. A composite assembled battery comprising a plurality of assembled batteries according to claim 8,
A composite assembled battery including at least two or more assembled batteries in which one assembled battery and the other assembled battery are electrically connected in series and / or in parallel.   A vehicle equipped with the assembled battery according to claim 8 or the composite assembled battery according to claim 9.

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