Battery module

Abstract

To provide an inexpensive battery module that houses multiple batteries.SOLUTION: A battery module 1 includes an electrode body 11, a non-aqueous electrolyte 15, a battery case 16 which does not contain metal foil and is made of a liquid junction prevention resin film, and which houses the electrode body 11 and the non-aqueous electrolyte 15 and hermetically seals it to prevent permeation of the non-aqueous electrolyte 15, and a plurality of batteries 10 having a plurality of electrode terminal plates 17A, 17B, 18A, 18B including at least one positive electrode terminal plate 17A, 17B and at least one negative electrode terminal plate 18A, 18B which are airtightly drawn from the inside of the battery case 16 to the outside of the battery case 16 through a space between peripheral portions 16CP, 16DP of the battery case 16, the batteries 10 which are electrically connected to each other by conducting the electrode terminal plate 17A, 18A of one battery 10 to the electrode terminal plate 17B, 18B of the other battery 10, and a metal module container 2 which is made of metal and houses the plurality of batteries 10 and hermetically seals them.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a battery module that houses a plurality of batteries. [Background technology]

[0002] Patent Document 1 discloses a laminated battery module in which a plurality of laminated batteries stacked on top of each other are housed in an exterior case (see, for example, FIG. 4). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-169135 Summary of the Invention [Problem to be solved by the invention]

[0004] In this laminated battery module, the exterior of each laminated battery is made of an expensive laminate film made of a metal foil such as aluminum foil and a resin layer to prevent the penetration of organic solvents, which make up the electrolyte, as well as moisture into the laminated battery. Furthermore, multiple laminated batteries are housed airtight in a metal case, which serves as the exterior case. This resulted in excessive moisture penetration resistance and high costs.

[0005] The present invention has been made in view of the above-mentioned circumstances, and aims to provide an inexpensive battery module that houses a plurality of batteries. [Means for solving the problem]

[0006] (1) One aspect of the present invention for solving the above problem includes a battery case that does not include an electrode assembly, a non-aqueous electrolyte, or a metal foil but is made of a liquid-junction preventing resin film, and that accommodates and airtightly seals the electrode assembly and the non-aqueous electrolyte to prevent permeation of the non-aqueous electrolyte; a plurality of batteries having a plurality of electrode terminal plates, including at least one positive electrode terminal plate and at least one negative electrode terminal plate, that are airtightly extended from the inside of the battery case to the outside of the battery case through a peripheral portion of the battery case, the plurality of batteries being electrically connected to each other by conducting the electrode terminal plate of one of the batteries to the electrode terminal plate of the other of the batteries; and a metal module container that accommodates and airtightly seals the plurality of batteries. Each of the plurality of batteries has four electrode terminal plates, including a pair of a first positive electrode terminal plate and a first negative electrode terminal plate, and a pair of a second positive electrode terminal plate and a second negative electrode terminal plate, and the first positive electrode terminal plate of one of the batteries is connected to the second positive electrode terminal plate of the other battery, and the first negative electrode terminal plate of one of the batteries is connected to the second negative electrode terminal plate of the other battery, so that the plurality of batteries are connected in parallel in a cascade configuration, and the metal module case has only a pair of positive electrode terminal members and negative electrode terminal members, and of the plurality of batteries connected in parallel in a cascade configuration, the battery located at one end has the first positive electrode terminal plate in an open state and the first negative electrode terminal plate connected to the negative electrode terminal member, and the battery located at the other end has the second negative electrode terminal plate in an open state and the second positive electrode terminal plate connected to the positive electrode terminal member. It is a battery module.

[0007] Each battery in this battery module is hermetically sealed and houses an electrode assembly and a nonaqueous electrolyte in a battery case made of a liquid-junction prevention resin film. This prevents electrolyte leakage or seepage through the battery case, resulting in a liquid junction (ionic short circuit) between batteries via the nonaqueous electrolyte. However, unlike so-called laminate films, the liquid-junction prevention resin film that forms the battery case is inexpensive, but does not contain a metal foil that prevents the permeation of water vapor and the like. Therefore, it cannot adequately prevent the penetration of water vapor from the outside of the battery into the battery interior. However, in this battery module, the metal module container houses and hermetically seals multiple batteries, so the penetration of water and water vapor into the metal module container, i.e., around the batteries, is essentially prevented. Thus, an inexpensive battery module can be created in which the metal module container prevents the penetration of water vapor into the batteries, even though the battery case is made of an inexpensive liquid-junction prevention resin film rather than a laminate film as the exterior of each battery. Additionally, in the battery module described above, the first positive terminal plate of one battery is connected to the second positive terminal plate of the other battery, and the first negative terminal plate of one battery is connected to the second negative terminal plate of the other battery, so that the batteries are connected in a cascaded configuration, which allows the built-in multiple batteries to be easily connected together to obtain a battery module in which the batteries are connected in parallel.

[0008] The battery may be a secondary battery such as a lithium ion secondary battery or a sodium ion secondary battery. The non-aqueous electrolyte may be prepared by dissolving an electrolyte salt in an organic solvent, such as cyclic carbonates such as propylene carbonate and ethylene carbonate, or chain carbonates such as dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.

[0009] The liquid junction prevention resin film used in the battery case is a film made of resin that prevents the permeation of the electrolyte. For example, in addition to resin films such as PT, PET, PP, PE, and olefin-based resins, multilayer films with multiple resin layers such as PP / PET can also be used.

[0010] Examples of batteries having multiple electrode terminal plates include batteries having one pair of positive and negative terminal plates, as well as batteries having multiple pairs of positive and negative terminal plates, such as two pairs.

[0011] The battery module may be configured in such a way that flat batteries are arranged in a straight line in the planar direction, connected to each other, and housed in a metal modular container, or in such a way that flat batteries are arranged in a grid pattern in the planar direction, connected to each other, and housed in a metal modular container, or in such a way that multiple flat batteries are stacked and connected to each other and housed in a metal modular container. Multiple batteries can be connected in parallel, in series, or in series-parallel.

[0012] (2) In the battery module described in (1) above, the electrode terminal plates of the batteries may be directly welded together.

[0013] In this battery module, the electrode terminal plates of the batteries are connected directly to each other without using a separately prepared bus bar or the like, which reduces the number of parts, resulting in a simpler and less expensive battery module.

[0014] As a welding method for directly welding the electrode terminal plates together, resistance welding, laser welding, ultrasonic welding, or the like can be appropriately adopted.

[0015] (3) In the battery module described in (2) above, the positive electrode terminal plate may be made of an aluminum plate, the negative electrode terminal plate may be made of a copper plate, and the positive electrode terminal plate of one battery and the negative electrode terminal plate of the other battery may be directly ultrasonically welded to each other.

[0016] When dissimilar metals, such as aluminum and copper plates, are joined by melting the base materials using spot welding or other methods, brittle intermetallic compounds may form in the molten area, causing the weld to fracture. In contrast, as described above, when an aluminum plate and a copper plate are connected by ultrasonic welding, the aluminum plate and the copper plate are solid-state joined, making it difficult for an intermetallic compound to form between the two and resulting in a stable connection.

[0017] (delete)

[0018] (delete)

[0019] (delete)

[0020] (delete)

[0021] Also preferred is a battery in which an electrode body and a non-aqueous electrolyte are surrounded and sealed in a battery case made of a liquid junction prevention resin film that prevents the passage of the non-aqueous electrolyte, and which has a pair of first positive electrode terminal plate and first negative electrode terminal plate, and a pair of second positive electrode terminal and second negative electrode terminal that are drawn from the inside of the battery case to the outside of the battery case through the peripheral portion of the battery case.

[0022] This battery has two pairs of positive and negative terminal plates. Therefore, when connecting multiple batteries, the first positive terminal plate of one battery is connected to the second positive terminal plate of the other battery, and the first negative terminal plate of one battery is connected to the second negative terminal plate of the other battery, so the batteries can be easily connected in a cascade configuration. This makes it easy to obtain a battery module in which multiple batteries are connected in parallel. Furthermore, because the battery case is made of a liquid-junction prevention resin film, which is less expensive than laminate film, the battery itself can be made inexpensive. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 2 is an explanatory diagram showing the internal structure of a battery module according to the first embodiment. [Figure 2] FIG. 1 is a plan view showing a four-terminal battery according to a first embodiment of the present invention. [Figure 3] 1 is a partially enlarged cross-sectional view showing the structure of a terminal portion of a four-terminal battery according to a first embodiment of the present invention. [Figure 4] FIG. 1 is a development view of a positive electrode plate used in a four-terminal battery according to the first and second embodiments. [Figure 5] FIG. 10 is a development view of a negative electrode plate used in a four-terminal battery according to the first and second embodiments. [Figure 6] 10 is a flowchart showing a manufacturing procedure for the battery module according to the first embodiment. [Figure 7] FIG. 1 is a plan view showing a battery group formed by interconnecting four-terminal batteries according to the first embodiment. [Figure 8] FIG. 10 is a perspective view showing a wall member with terminals of a battery module according to the first embodiment. [Figure 9] FIG. 10 is a perspective view showing a bottom plate member of a battery module according to the first reference embodiment. [Figure 10] FIG. 1 is a perspective view showing a container body member according to the first embodiment. [Figure 11] FIG. 10 is a plan view showing a state in which a plurality of interconnected four-terminal batteries are housed in a container body member according to the first embodiment. [Figure 12]FIG. 1 is a plan view of a battery module according to a first reference embodiment. [Figure 13] FIG. 10 is a plan view showing a four-terminal battery according to a second embodiment. [Figure 14] FIG. 10 is an explanatory diagram showing the internal structure of a battery module according to a second embodiment. [Figure 15] FIG. 2 is an explanatory diagram showing the internal structure of a battery module according to the embodiment. [Figure 16] FIG. 10 is an explanatory diagram showing the internal structure of a battery module according to a third embodiment. [Figure 17] FIG. 10 is an explanatory diagram showing the internal structure of a battery module according to a fourth embodiment. [Figure 18] FIG. 10 is a plan view showing a two-terminal battery according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] ( Reference form 1 ) Hereinafter, the present invention Reference form 1 A four-terminal battery 10 (hereinafter simply referred to as a battery) and a plurality of Reference form 1 1 to 12, a battery module 1 containing a battery group 5 in which four (4) batteries 10 are interconnected will be described. The batteries 10 are sealed lithium-ion secondary batteries with a roughly rectangular parallelepiped shape, and the battery module 1 is mounted on various devices such as vehicles such as hybrid cars, plug-in hybrid cars, and electric cars, as well as drones.

[0025] Book Reference form 1 The battery module 1 (see Figs. 1 and 12) comprises a battery group 5, a module container 2 that houses and hermetically seals the battery group 5, and two pairs (four in total) of positive electrode terminal members 6 and negative electrode terminal members 7 fixed to the module container 2 via insulating members 8. The insulating members 8 insulate the module container 2 from the positive electrode terminal members 6 or negative electrode terminal members 7. Reference form 1The battery module 1 has four built-in batteries 10 connected in parallel. In this specification, the length direction AH, width direction BH, and thickness direction CH of the battery module 1, batteries 10, etc. are defined as the directions shown in each drawing, such as Figures 1 and 2, and will be described.

[0026] The module container 2 is made of metal ( Reference form 1 The module container 2 is made of a material such as aluminum (for example, aluminum) and has the shape of a rectangular parallelepiped box that is long in the longitudinal direction AH. The module container 2 comprises a container body 3 (see FIG. 10) in the shape of a rectangular cylinder with a bottom and having a rectangular opening 3K that is long in the longitudinal direction AH, and a lid 4 (see FIG. 12) in the shape of a rectangular flat plate that is long in the longitudinal direction AH and that closes the opening 3K of the container body 3. The positive electrode terminal member 6 and the negative electrode terminal member 7 described above are fixed to a pair of wall members 3W located on one side AH1 and the other side AH2 in the longitudinal direction AH, respectively, via insulating members 8, while penetrating the wall members 3W.

[0027] Battery group 5 Reference form 1 The four-terminal battery 10 (see FIGS. 2 and 3) has a generally rectangular parallelepiped shape and includes a pair of first positive terminal plate 17A and first negative terminal plate 18A that protrude from one side AH1 (the right side in FIG. 2) in the longitudinal direction AH. It also includes a pair of second positive terminal plate 17B and second negative terminal plate 18B that protrude from the other side AH2 (the left side in FIG. 2). More specifically, in the battery 10, the first positive terminal plate 17A and the second positive terminal plate 17B (hereinafter collectively referred to as the positive terminal plates 17A and 17B) are each located on one side BH1 in the width direction BH (the upper side in FIG. 2). Meanwhile, the first negative terminal plate 18A and the second negative terminal plate 18B (hereinafter collectively referred to as the negative terminal plates 18A and 18B) are each located on the other side BH2 in the width direction BH (the lower side in FIG. 2).

[0028] This battery 10 contains an electrode assembly 11 and an electrolyte 15 in a battery case 16 formed from a liquid-junction prevention resin film. Additionally, the battery 10 has two pairs (four in total) of positive electrode terminal plates 17A, 17B and negative electrode terminal plates 18A, 18B that are airtightly extended from the interior of the battery case 16 through a peripheral edge 16P of the battery case 16, specifically, through the space between peripheral edges 16CP, 16DP of battery case members 16C, 16D, in the longitudinal direction AH. A portion of the electrolyte 15 contained in the battery case 16 is impregnated within the electrode assembly 11, and the other portion is collected in the space outside the electrode assembly 11 within the battery case 16.

[0029] The electrode assembly 11 housed in the battery case 16 is a so-called flat wound electrode assembly, which is formed by stacking a strip-shaped positive electrode plate 12 long in the longitudinal direction LH shown in FIG. 4 and a strip-shaped negative electrode plate 13 long in the longitudinal direction LH shown in FIG. 5 via a pair of strip-shaped separators 14, winding them around an axis 11AX, and pressing them in a direction perpendicular to the paper surface in FIG. 1 to make them flat. This electrode assembly 11 is housed in the battery case 16 in a position where the axis 11AX coincides with the length direction AH of the battery 10 (see FIG. 2). In this specification, the longitudinal direction LH, width direction WH, and thickness direction TH of the positive electrode plate 12, negative electrode plate 13, etc. are defined as the directions shown in FIGS. 4 and 5. In addition, in this specification, Reference form 1 In the above, the electrode body 11 is of a flat wound type, but a laminated type electrode body may also be used.

[0030] Of the electrode body 11, the strip-shaped positive electrode plate 12 includes a strip-shaped positive electrode current collector foil 12F made of aluminum foil and a strip-shaped positive electrode active material layer 12A laminated on both surfaces of the positive electrode current collector foil 12F (see FIG. 4). The positive electrode active material layer 12A is made of positive electrode active material particles, conductive particles, and a binder (not shown). Reference form 1 In this battery, lithium transition metal composite oxide particles, specifically, for example, lithium nickel cobalt manganese composite oxide particles, are used as the positive electrode active material particles, acetylene black (AB), for example, is used as the conductive particles, and polyvinylidene fluoride (PVDF), for example, is used as the binder.

[0031] In the positive electrode current collector foil 12F of the strip-shaped positive electrode plate 12, one-side positive electrode tab portion 12T1 and other-side positive electrode tab portion 12T2 protruding toward one side WH1 and other side WH2 in the width direction WH (upper and lower sides in FIG. 4 ) than the positive electrode active material layer 12A are provided with a gap in the longitudinal direction LH. The one-side positive electrode tab portion 12T1 and other-side positive electrode tab portion 12T2 are not provided with the positive electrode active material layer 12A. The electrode body 11 is formed by winding and flattening the positive electrode plate 12 and the negative electrode plate 13 so that the multiple one-side positive electrode tab portions 12T1 are arranged overlapping each other. Therefore, the multiple overlapping one-side positive electrode tab portions 12T1 are collected and connected to an internal connection portion 17AI of a first positive electrode terminal plate 17A made of aluminum, as described below (see FIGS. 2 and 3 ). Similarly, in the state of the electrode body 11, the multiple other-side positive electrode tab portions 12T2 are also arranged overlapping each other, and therefore the multiple other-side positive electrode tab portions 12T2 are gathered together and connected to the internal connection portion 17BI of the second positive electrode terminal plate 17B.

[0032] On the other hand, the strip-shaped negative electrode plate 13 includes a strip-shaped negative electrode current collector foil 13F made of copper foil and a strip-shaped negative electrode active material layer 13A laminated on both surfaces of the negative electrode current collector foil 13F (see FIG. 5). The negative electrode active material layer 13A is made of negative electrode active material particles and a binder, not shown. Reference form 1 In this example, graphite particles are used as the negative electrode active material particles, and carboxymethyl cellulose (CMC) is used as the binder.

[0033] In the negative electrode current collector foil 13F of the strip-shaped negative electrode plate 13, one-side negative electrode tab portion 13T1 and other-side negative electrode tab portion 13T2 are provided at intervals on one side WH1 and other side WH2 in the width direction WH (upper and lower sides in FIG. 5 ) of the negative electrode active material layer 13A. The one-side negative electrode tab portion 13T1 and other-side negative electrode tab portion 13T2 are not provided with the negative electrode active material layer 13A. The electrode body 11 is formed by winding and flattening the positive electrode plate 12 and the negative electrode plate 13 so that the multiple one-side negative electrode tab portions 13T1 are also arranged overlapping each other. Therefore, the multiple overlapping one-side negative electrode tab portions 13T1 are gathered together and connected to an internal connection portion 18AI of a first negative electrode terminal plate 18A made of copper, as described below (see FIGS. 2 and 3 ). Similarly, in the state of the electrode body 11, the multiple other-side negative electrode tab portions 13T2 are also arranged overlapping each other, and therefore the multiple other-side negative electrode tab portions 13T2 are gathered together and connected to the internal connection portion 18BI of the second negative electrode terminal plate 18B.

[0034] The pair of strip-shaped separators 14 can be made of porous resin sheets made of polyolefin resin such as polyethylene (PE) or polypropylene (PP). Reference form 1 In this example, a separator with a three-layer structure of PE / PP / PE was used. Note that a separator having a heat-resistant layer containing an inorganic filler provided on the surface of the separator 14 may also be used. Examples of inorganic fillers that can be used include alumina, boehmite, aluminum hydroxide, and titania.

[0035] The positive electrode terminal plates 17A, 17B are made of aluminum and have a long, narrow plate shape. Internal connection portions 17AI, 17BI forming one end of the positive electrode terminal plates 17A, 17B are connected to one side positive electrode tab portion 12T1 or the other side positive electrode tab portion 12T2, respectively, of the integrated positive electrode plates 12 constituting the electrode assembly 11. On the other hand, external terminal portions 17AO, 17BO forming the other end of the positive electrode terminal plates 17A, 17B are drawn out to the outside of the battery case 16.

[0036] On the other hand, the negative electrode terminal plates 18A, 18B are made of copper and have a long, narrow plate shape, similar to the positive electrode terminal plates 17A, 17B. Internal connection portions 18AI, 18BI forming one end of the negative electrode terminal plates 18A, 18B are connected to one side negative electrode tab portion 13T1 or the other side negative electrode tab portion 13T2, respectively, which are integrated among the negative electrode plates 13 constituting the electrode assembly 11. On the other hand, external terminal portions 18AO, 18BO forming the other end of the negative electrode terminal plates 18A, 18B are drawn out to the outside of the battery case 16.

[0037] The electrolyte solution 15 is a non-aqueous electrolyte solution in which a supporting salt is dissolved in a non-aqueous solvent. Examples of the non-aqueous solvent include carbonate-based solvents such as ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate. Reference form 1 In the study, an organic solvent consisting of ethylene carbonate, ethyl methyl carbonate, and dimethyl carbonate mixed in a weight ratio of 3:3:4 is used. LiPF6 is also used as the supporting electrolyte.

[0038] As shown in FIG. 2, the battery case 16 has a rectangular shape in plan view that is slightly larger than the electrode assembly 11 to be housed, and is formed by stacking a pair of battery case members 16C and 16D made of preformed liquid junction prevention resin films. Reference form 1 In the battery case members 16C and 16D, a two-layer PP / PET film is used as the liquid junction prevention resin film with the PP side facing inward. The battery case members 16C and 16D each have a recessed housing portion 16CR or 16DR that houses the electrode assembly 11, and a flat rectangular annular peripheral portion 16CP or 16DP formed around the entire periphery of the housing portion 16CR or 16DR (see FIG. 3).

[0039] The battery case 16 accommodates the electrode body 11 between the accommodation portions 16CR, 16DR of a pair of battery case members 16C, 16D, and has the external terminal portions 17AO, 17BO of the positive electrode terminal plates 17A, 17B and the external terminal portions 18AO, 18BO of the negative electrode terminal plates 18A, 18B extended to the outside of the battery case 16. The peripheral portions 16CP, 16DP are overlapped and airtightly heat-sealed to form a flat, rectangular, annular peripheral portion 16P.

[0040] In addition, with respect to the positive electrode terminal plates 17A, 17B and the negative electrode terminal plates 18A, 18B, intermediate portions 17AM, 17BM, 18AM, 18BM between the internal connection portions 17AI, 17BI, 18AI, 18BI and the external terminal portions 17AO, 17BO, 18AO, 18BO are respectively sandwiched between the peripheral portions 16CP, 16DP of the battery case 16 and are hermetically heat-sealed. A M,18 A The surface of the intermediate portion 17AM, 17BM, 18AM, 18BM is roughened, and the adhesion between the intermediate portion 17AM and the peripheral portion 16CP, 16DP is improved. good Alternatively, a resin layer made of metal-adhesive PP may be interposed.

[0041] In this way, Reference form 1 In this battery 10, the electrode assembly 11 and the electrolyte 15 are housed in a battery case 16 made of a liquid-junction preventing resin film and hermetically sealed. This prevents the electrolyte 15 from leaking or seeping out through the battery case 16, preventing a liquid junction (ionic short circuit) between the batteries 10 via the electrolyte 15. Moreover, because the battery case 16 is made of a liquid-junction preventing resin film that is less expensive than a laminate film containing a metal foil such as aluminum foil, the battery 10 can be made inexpensive, and therefore the battery module 1 using this battery 10 can also be made inexpensive.

[0042] However, although the liquid junction prevention resin film is inexpensive, unlike the laminate film, it does not contain a metal foil such as aluminum foil that prevents the permeation of gases such as water vapor, and therefore cannot adequately prevent the penetration of water vapor from the outside of the battery into the inside of the battery through the battery case 16.

[0043] However, Reference form 1In this battery module 1, a module container 2 made of a metal such as aluminum houses and hermetically seals a plurality of batteries 10 that make up a battery group 5. This prevents water, water vapor, and the like from entering the module container 2. In other words, water, water vapor, and the like are prevented from entering the surroundings of the batteries 10. Thus, even though a battery case 16 made of an inexpensive liquid-junction prevention resin film is used as the exterior of each battery 10, water vapor can be prevented from entering the batteries, and the battery module can also be made inexpensive.

[0044] In addition, this Reference form 1 In this example, the four-terminal batteries 10 are interconnected to form a battery group 5 (see FIG. 1). Specifically, for example, the first positive electrode terminal plate 17A of the battery 10 on the far left in FIG. 1 is directly welded by laser welding to the second positive electrode terminal plate 17B of the battery 10 second from the left in FIG. 1. At the same time, the first negative electrode terminal plate 18A of the battery 10 on the far left is directly welded by laser welding to the second negative electrode terminal plate 18B of the battery 10 second from the left. In this way, a plurality of (this Reference form 1 In this example, four batteries 10 are connected in parallel in a cascade configuration. Furthermore, of the batteries 10 at both ends of the battery group 5, the terminal plates located at both ends and not connected to other batteries 10 are directly welded by laser welding to the positive electrode terminal member 6 or the negative electrode terminal member 7 provided on the module case 2. That is, of the battery 10 at the left end in FIG. 1, the second positive electrode terminal plate 17B is located at the end of the module case 2 in the longitudinal direction AH. others One side AH 2 The first positive terminal plate 17A of the battery 10 on the right side in FIG. 1 is directly welded to the positive terminal member 6, and the second negative terminal plate 18B is directly welded to the negative terminal member 7. In addition, the first positive terminal plate 17A of the battery 10 on the right side in FIG. 1 is directly welded to the negative terminal member 7 in the longitudinal direction AH of the module container 2. one One side AH 1 The first negative electrode terminal plate 18A is directly welded to the positive electrode terminal member 6, and the first negative electrode terminal plate 18A is directly welded to the negative electrode terminal member 7.

[0045] In this way, Reference form 1The four-terminal batteries 10 can be easily connected together in a cascading fashion, allowing multiple built-in four-terminal batteries 10 to be easily connected together to obtain a battery module 1 in which the batteries are connected in parallel. Moreover, the book Reference form 1 In this case, the terminal plates of the four-terminal batteries 10 are directly connected to each other without using any internal connection members such as bus bars, which further reduces the number of parts, resulting in a battery module 1 with a simpler configuration and lower cost.

[0046] Next is the book Reference form 1 The manufacture of the battery 10 and battery module 1 will be described using the flowchart in Figure 6 and other related figures. First, in a blank battery formation step S1, the positive electrode plate 12, the negative electrode plate 13, and the separator 14 are wound and flattened to form the electrode body 11. Specifically, the electrode body 11 is housed in a battery case member 16D, and is connected to positive electrode terminal plates 17A, 17B and negative electrode terminal plates 18A, 18B. The battery case member 16C is then placed over the electrode body 11, and peripheral edges 16CP, 16DP are heat-welded together to manufacture a battery 10 without a blank electrolyte 15. In addition, in the unfilled battery 10, a portion of the peripheral portion 16P of the battery case 16 (for example, the portion between the first positive electrode terminal plate 17A and the first negative electrode terminal plate 18A, and the portion between the second positive electrode terminal plate 17B and the second negative electrode terminal plate 18B) is left unsealed, so that the electrolyte 15 can be poured into the battery case 16 through the unsealed portion (not shown) of the peripheral portion 16P in the liquid filling step S2 described next.

[0047] In the liquid injection step S2, as described above, the electrolyte 15 is injected into the battery case 16 through the unsealed portion of the peripheral edge 16P of the battery case 16. As a result, the electrode body 11 is impregnated with the electrolyte 15.

[0048] Then, in an initial charging step S3, the battery 10 is initially charged at room temperature under the condition of 0.5C-CCCV charging (SOC 90%). Then, in a sealing step S4, the unsealed portion of the peripheral edge 16P of the battery case 16 is sealed to hermetically seal the battery 10.

[0049] Furthermore, in the high-temperature aging step S5, the battery 10 is left for 20 hours in an environment at 60° C. Thereafter, in the inspection step S6, an inspection is carried out for the presence or absence of short circuits, and the battery 10 is completed.

[0050] In the battery grouping process S7, the completed multiple (main Reference form 1 In this example, four batteries 10 are used, and the first positive terminal plate 17A of one battery 10 is directly connected by laser welding to the second positive terminal plate 17B of the other battery 10, and the first negative terminal plate 18A of one battery 10 is directly connected by laser welding to the second negative terminal plate 18B of the other battery 10, thereby connecting the batteries 10 in parallel in a cascade configuration. In this way, a battery group 5 shown in FIG. 7 is formed.

[0051] Meanwhile, in parallel with the manufacture of the battery 10 and the battery group 5, the container body 3 is formed in the container body forming step S8 (see FIG. 10 ). Specifically, as shown in FIG. 8 , a wall member 3W is punched out of an aluminum plate (not shown) to form a safety valve portion 3WS and to form through-holes (not shown) for inserting the positive electrode terminal member 6 and the negative electrode terminal member 7. Next, the positive electrode terminal member 6 and the negative electrode terminal member 7, which have been separately formed, are inserted into the through-holes, and an insulating member 8 made of an insulating resin (e.g., PPS, polyamide, etc.) is formed by injection molding. In this way, a terminal-equipped wall member 3TW is formed in which the positive electrode terminal member 6 and the negative electrode terminal member 7 are fixed to the wall member 3W while insulating the wall member 3W from the positive electrode terminal member 6 and the negative electrode terminal member 7 with the insulating member 8.

[0052] Separately, as shown in Figure 9, an aluminum plate (not shown) is bent to form a bottom side plate member 3BS having a rectangular bottom portion 3B that is long in the longitudinal direction AH and rectangular long side portions 3S1, 3S2 that rise in the thickness direction CH from both sides of the width direction BH of the bottom portion 3B and are long in the longitudinal direction AH.

[0053] 10, terminal-equipped wall members 3TW are welded to both end portions of the bottom side plate member 3BS in the longitudinal direction AH to form a bottomed, square tubular container body 3. The container body 3 has a rectangular opening 3K that is long in the longitudinal direction AH.

[0054] In the lid forming step S9, the lid 4 having a rectangular flat plate shape that is long in the length direction AH is formed in parallel with the manufacture of the container body 3 (see FIG. 12).

[0055] In the accommodation step S10, the battery group 5 is placed and accommodated in the container body 3. Next, in the terminal connection step S11, the positive electrode terminal plates 17A, 17B and negative electrode terminal plates 18A, 18B of the battery group 5, which are located at both ends in the longitudinal direction AH and are not connected to other batteries 10, are directly welded by laser welding to the positive electrode terminal members 6 or the negative electrode terminal members 7 provided at both ends of the container body 3 in the longitudinal direction AH. That is, in the leftmost battery 10 in FIG. 11 , the second positive electrode terminal plate 17B is directly welded to the positive electrode terminal member 6 on the other side AH2 of the container body 3 in the longitudinal direction AH, and the second negative electrode terminal plate 18B is directly welded to the negative electrode terminal member 7. In addition, in the rightmost battery 10 in FIG. 11 , the first positive electrode terminal plate 17A is directly welded to the positive electrode terminal member 6 on one side AH1 of the container body 3 in the longitudinal direction AH, and the first negative electrode terminal plate 18A is directly welded to the negative electrode terminal member 7.

[0056] Furthermore, in the container sealing process S12, the lid 4 is placed over the container body 3 to close the opening 3K, and the peripheral portion of the lid 4 is laser welded to the container body 3 along the entire circumference to form an airtightly sealed module container 2, thereby completing the battery module 1.

[0057] As mentioned above, Reference form 1 In the manufacturing process, the battery module 1 was manufactured by connecting the initially charged and sealed batteries 10 to each other in advance to form the battery group 5, and then accommodating and arranging the battery group 5 in the container body 3 in the accommodation step S10.

[0058] However, other manufacturing procedures can also be employed. For example, a plurality of unfilled batteries 10 are placed in the container body 3, connected to each other, and also to the positive electrode terminal members 6 and negative electrode terminal members 7 of the container body 3. Then, each battery 10 is filled with electrolyte within the container body 3, and initial charging is performed via the positive electrode terminal members 6 and negative electrode terminal members 7, after which each battery 10 is sealed. After further high-temperature aging, the container body 3 is covered with the lid 4 and welded around the entire periphery, and the module container 2 is sealed to complete the battery module 1. Such procedures can also be employed.

[0059] ( Reference form 2 ) Reference form 1 1 and 2 show a four-terminal battery 10 and a battery module 1 using four of these batteries 10. In this four-terminal battery 10, both positive terminal plates 17A and 17B are provided on one side BH1 in the width direction BH (the upper side in FIG. 2), and both negative terminal plates 18A and 18B are provided on the other side BH2 in the width direction BH (the upper side in FIG. 2). under It has a form provided on the side.

[0060] In response to this, Reference form 2 The battery 110 is similar to the battery 10 in that it has two pairs of positive terminal plates 117A, 117B and negative terminal plates 118A, 118B. The battery 110 also uses the same battery case 16 as the battery 10. However, as can be easily understood by referring to FIG. 13, the first positive terminal plate 117A provided on one side AH1 (right side in FIG. 13) of the length direction AH of the battery 110 is arranged on one side BH1 (upper side in FIG. 13) of the width direction BH. However, the second positive terminal plate 117B provided on the other side AH2 (left side in FIG. 13) of the length direction AH is arranged on the other side BH2 (lower side in FIG. 13) of the width direction BH, which is opposite to the battery 10. Similarly, the first negative terminal plate 1 18A is disposed on the other side BH2 in the width direction BH (the lower side in FIG. 13), and the second negative electrode terminal board 1 13. The second positive terminal plate 117B and the second negative terminal plate 118B are disposed on one side BH1 in the width direction BH (upper side in FIG. 13). That is, the arrangement of the second positive terminal plate 117B and the second negative terminal plate 118B is reversed from that of the battery 10.

[0061] In order to enable the arrangement of the positive electrode terminal plates 117A, 117B and the negative electrode terminal plates 118A, 118B as described above, the arrangement of the positive electrode tab portion 112T2 on one side relative to the positive electrode tab portion 112T1 on the other side of the positive electrode current collector foil 112F of the positive electrode plate 112 is as shown by the dashed line in FIG. Reference form 1 Similarly, as shown by the broken line in FIG. 5, in the negative electrode current collector foil 113F of the negative electrode plate 113, the arrangement of the negative electrode tab portion 113T2 on one side relative to the negative electrode tab portion 113T1 on the other side is Reference form 1 The electrode assembly 111, which is formed by winding and flattening the positive electrode plate 112, the negative electrode plate 113, and the separator 14, has a configuration in which a one-side positive electrode tab portion 112T1 is arranged at a position facing the first positive electrode terminal plate 117A, a other-side positive electrode tab portion 112T2 is arranged at a position facing the second positive electrode terminal plate 117B, a one-side negative electrode tab portion 113T1 is arranged at a position facing the first negative electrode terminal plate 118A, and a other-side negative electrode tab portion 113T2 is arranged at a position facing the second negative electrode terminal plate 118B.

[0062] And books Reference form 2 In the battery module 101, as shown in FIG. 14, a battery group 105 in which four batteries 110 are interconnected in a cascade configuration is Reference form 1 The module is housed in a similar module container 2 and sealed airtight.

[0063] Book Reference form 2 In this battery 110 (see FIG. 13), the electrode assembly 111 and the electrolyte 15 are also housed in a battery case 16 made of a liquid junction prevention resin film and sealed airtight. 1 This prevents a liquid short circuit (ionic short circuit) between the cells 10 via the electrolyte 15. Furthermore, since the battery case 16 is made of a liquid short circuit prevention resin film that is less expensive than a laminate film, the battery 110 can be made inexpensive. 1 The battery module 101 using the battery 10 can also be made inexpensive.

[0064] Also, this Reference form 2 In this battery module 101, a module container 2 made of aluminum houses and hermetically seals a plurality of batteries 110 that make up a battery group 105. This prevents water, water vapor, and the like from entering the module container 2, and therefore the surroundings of the batteries 110. Thus, even though a battery case 16 made of an inexpensive liquid-junction prevention resin film is used as the exterior of each battery 110, water vapor can be prevented from entering the batteries 110, and the battery module 101 can also be made inexpensive.

[0065] ( Embodiment ) Reference form 1 and Reference form 2 The battery module 1, 101 uses four-terminal batteries 10, 110, and a pair of positive and negative terminal members 6, 7 are provided on each of the wall members 3W on both sides of the module container 2 in the longitudinal direction AH.

[0066] In contrast, as shown in Figure 15, Embodiment The battery module 201 uses a battery group 5 connected to four-terminal batteries 10, Reference form 1 15. However, it differs from the battery module 1 in that only the negative electrode terminal member 7 is provided on the wall member 203W on one side AH1 (the right side in FIG. 15) in the longitudinal direction AH of the module container 202, and only the positive electrode terminal member 6 is provided on the wall member 203W on the other side AH2 (the left side in FIG. 15).

[0067] However, this Embodiment In the battery module 201, four batteries 10 are electrically connected in parallel between the positive electrode terminal member 6 and the negative electrode terminal member 7. Reference form 1 The battery module 201 provided with only one pair of positive electrode terminal member 6 and negative electrode terminal member 7 can also be used as a battery module in the same way.

[0068] Book EmbodimentIn the battery module 201, the module container 202 made of aluminum prevents water and water vapor from entering the module container 202 and therefore the surroundings of the batteries 10. Thus, even though the battery case 16 made of an inexpensive liquid junction prevention resin film is used as the exterior of each battery 10, water vapor can be prevented from entering the batteries 10, and the battery module 201 can also be made cheaper.

[0069] In addition, Embodiment In the example shown, the positive electrode terminal member 6 and the negative electrode terminal member 7 are disposed with a large gap between them in the longitudinal direction AH. However, the pair of positive electrode terminal member 6 and negative electrode terminal member 7 may be provided only on the wall member 203W on one side AH1 in the longitudinal direction AH of the module container 202. Alternatively, the pair of positive electrode terminal member 6 and negative electrode terminal member 7 may be provided only on the wall member 203W on the other side AH2 in the longitudinal direction AH. Furthermore, of the four batteries 10 that make up the battery group 5, the leftmost battery 10 may be replaced with a three-terminal battery that does not have the second negative electrode terminal plate 18B, and the rightmost battery 10 may be replaced with a three-terminal battery that does not have the first positive electrode terminal plate 17A.

[0070] ( Reference form 3 ) Reference form 1,2 and Embodiment In the battery modules 1, 101, 201, a battery group 5, 105 in which a plurality of batteries 10, 110 are arranged in the longitudinal direction AH is housed in a rectangular parallelepiped module container 2, 202 that is long in the longitudinal direction AH. The arrangement of the plurality of batteries may also be in other forms.

[0071] Book Reference form 3 In the battery module 301, as shown in FIG. Reference form 3 In this example, three batteries 10 (see FIG. 2) are stacked in the thickness direction CH, and the positive electrode terminal plates 17A, 17B and negative electrode terminal plates 18A, 18B of each battery 10 are bent 90 degrees to form a V-shape and connected to each other by ultrasonic welding to form a battery group 305. Reference form 1 Compared to the module container 2 used in the battery module 1 (see Figure 1), Reference form 3The module container 302 used in the above has a short length AH dimension and a large thickness CH dimension, and the length AH and thickness CH dimensions are set to be large enough to accommodate a battery group 305 in which three batteries 10 are stacked. Reference form 1 Like the module container 2, Reference form 3 The module container 302 also comprises a rectangular cylindrical container body 303 with a bottom, and a lid 304 that closes a rectangular opening 303K of the container body 303.

[0072] The container body 303 also has wall members 303W on both sides in the longitudinal direction AH. Reference form 1 Like the wall member 3W of the container body 3, the wall member 303W is provided with a pair of positive and negative terminal members 6 and 7 insulated from the wall member 303W via an insulating member 8. However, on one side in the longitudinal direction AH, AH1 In the wall member 303W (on the right side in FIG. 16), the pair of positive electrode terminal member 6 and negative electrode terminal member 7 are formed at positions biased toward the other side CH2 in the thickness direction CH (the lower side in FIG. 16). others side AH2 In the wall member 303W (on the left side in FIG. 16), the pair of positive and negative terminal members 6 and 7 are formed at positions biased toward one side CH1 (upper side in FIG. 16) in the thickness direction CH for connection with the battery 10.

[0073] Book Reference form 3 In the battery module 301, a plurality of (main) Reference form 3 The point where the three batteries 10 are electrically connected in parallel is Reference form 1 This is the same as the battery module 1.

[0074] In addition, this Reference form 3In this battery module 301, the aluminum module container 302 prevents water, water vapor, and the like from entering the module container 302, and therefore the surroundings of the batteries 10. Thus, even though the battery case 16 made of an inexpensive liquid junction prevention resin film is used as the exterior of each battery 10, water vapor can be prevented from entering the batteries 10, and the battery module can also be made inexpensive.

[0075] In addition, Reference form 3 So, Reference form 1 The same battery 10 (see FIG. 2) was used, but instead of the battery 10, Reference form 2 The same four-terminal battery 110 may be used.

[0076] ( Reference form 4 ) Reference forms 1 and 2, embodiment and Reference form 3 1 shows a battery module 1, 101, 201, 301 in which a battery group 5, 105, 305 in which four-terminal batteries 10, 110 are electrically connected in parallel to each other is housed in a module container 2, 202, 302.

[0077] In response to this, Reference form 4 The battery module 401 (see FIG. 17) uses two-terminal batteries 410 (see FIG. 18) each having a pair of positive terminal member 6 and negative terminal member 7 (two in total), and Reference form 4 The difference is that the battery group 405 is made up of four batteries 410 electrically connected in series. Reference form 1 Unlike the module container 2, Reference form 4 In the module container 402, the wall member 403W located on one side AH1 in the longitudinal direction AH is provided with only the negative electrode terminal member 7 via an insulating member 8, and the wall member 403W located on the other side AH2 is provided with only the positive electrode terminal member 6 via an insulating member 8.

[0078] The book shown in Figure 18 Reference form 4 The battery 410 is Reference form 1The same battery case 16 as that used for the battery 10 is used. However, only a negative electrode terminal plate 418 made of a copper plate is provided on one side AH1 (the right side in FIG. 18) of the battery 410 in the longitudinal direction AH, and only a positive electrode terminal plate 417 made of an aluminum plate is provided on the other side AH2 (the left side in FIG. 18) of the battery 410 in the longitudinal direction AH.

[0079] Although not described in detail, in order to enable the placement of the positive electrode terminal plate 417 and the negative electrode terminal plate 418 as described above, only a positive electrode tab portion 412T is formed on the positive electrode plate 412 constituting the electrode assembly 411 of the battery 410. Similarly, only a negative electrode tab portion 413T is formed on the negative electrode plate 413. As a result, in the electrode assembly 411 formed by winding and flattening the positive electrode plate 412, the negative electrode plate 413, and the separator 14, a plurality of negative electrode tab portions 413T are gathered on one side AH1 in the longitudinal direction AH (the right side in FIG. 18) and welded to the negative electrode terminal plate 418. In addition, a plurality of positive electrode tab portions 412T are gathered on the other side AH2 in the longitudinal direction AH (the left side in FIG. 18) and welded to the positive electrode terminal plate 417.

[0080] And books Reference form 4 In this example, four batteries 410 are electrically connected in series to form a battery group 405 by directly connecting the positive terminal plate 417 of one battery 410 to the negative terminal plate 418 of the other battery 410 by ultrasonic welding. When dissimilar metals, such as aluminum and copper plates, are joined by melting the base metals, such as by spot welding, a brittle intermetallic compound is formed in the molten area, which can cause fractures at the welded area. Reference form 4 As described above, the positive electrode terminal plate 417 and the negative electrode terminal plate 418, i.e., the aluminum plate and the copper plate, are connected by ultrasonic welding, so that the aluminum plate and the copper plate are solid-state welded, which makes it difficult for an intermetallic compound to be formed between them, and a stable connection can be obtained.

[0081] Book Reference form 4In this battery 410 (see FIG. 18), the electrode assembly 411 and electrolyte 15 are housed in a battery case 16 made of an anti-liquid-junction resin film and hermetically sealed. This prevents liquid junctions between the batteries 410. Moreover, because the battery case 16 is made of an inexpensive anti-liquid-junction resin film, the battery 410 can be made inexpensive, and therefore the battery module 401 using this battery 410 can also be made inexpensive.

[0082] Also, this Reference form 4 In this battery module 401, a module container 402 made of aluminum houses and hermetically seals a plurality of batteries 410 that make up a battery group 405. This prevents water, water vapor, and the like from entering the module container 402, and therefore the surroundings of the batteries 410. Thus, even though a battery case 16 made of an inexpensive liquid-junction prevention resin film is used as the exterior of each battery 410, water vapor can be prevented from entering the batteries 410, and the battery module 401 can also be made inexpensive. Moreover, in this battery module 401, the positive electrode terminal plate 417 of one battery 410 is connected to the negative electrode terminal plate 418 of the other battery 410, and the four built-in batteries 410 are connected in series, making it possible to create a battery module 401 with a simple configuration and at low cost.

[0083] Furthermore, Reference form 4 In the example shown, one battery 410 has one negative electrode terminal plate 418 on one side AH1 in the length direction AH and one positive electrode terminal plate 417 on the other side AH2 in the length direction AH. However, two or more negative electrode terminal plates 418 may be provided on one side AH1 in the length direction AH and two or more positive electrode terminal plates 417 on the other side AH2 in the length direction AH, and the batteries may be connected in series. In this case, the batteries can be connected with even lower resistance.

[0084] In the above, the present invention Embodiment However, the present invention is not limited to the embodiments, and can be modified and applied as appropriate without departing from the spirit of the present invention. [Explanation of symbols]

[0085] 1,101,201,301,401 Battery Module 2,202,302,402 Modular container (metallic modular container) 3,303,403 Container body 3W,203W,303W,403W wall parts 5,105,305,405 battery group 6 Positive electrode terminal material 7 Negative electrode terminal member 10,110 4-terminal battery (battery) 410 2-terminal battery (battery) 11,111,411 Electrode body 15 Electrolyte (non-aqueous electrolyte) 16 Battery case 16P Periphery 17A 1st positive terminal board (positive terminal board, electrode terminal board) 17B 2nd positive terminal board (positive terminal board, electrode terminal board) 417 Positive terminal board

Claims

1. electrode body, non-aqueous electrolyte, a battery case that does not contain a metal foil and is made of a liquid junction prevention resin film, that accommodates the electrode assembly and the non-aqueous electrolyte and airtightly seals them to prevent permeation of the non-aqueous electrolyte; and a plurality of electrode terminal plates including at least one positive electrode terminal plate and at least one negative electrode terminal plate, which are airtightly drawn from the inside of the battery case to the outside of the battery case through the peripheral edge of the battery case; A plurality of batteries, The electrode terminal plate of one of the batteries is electrically connected to the electrode terminal plate of the other battery. A plurality of the batteries; a metal module container made of metal that houses and hermetically seals the plurality of batteries, Each of the plurality of batteries comprises: a pair of a first positive electrode terminal plate and a first negative electrode terminal plate; a pair of second positive electrode terminal plate and second negative electrode terminal plate, so that the total number of electrode terminal plates is four; the first positive terminal plate of one of the batteries is connected to the second positive terminal plate of the other battery, and the first negative terminal plate of one of the batteries is connected to the second negative terminal plate of the other battery, so that the plurality of batteries are connected in parallel in a cascade configuration; The metal modular container comprises: The battery has only one pair of positive and negative terminal members, Among the plurality of batteries connected in parallel in a cascade configuration, The battery located at one end has the first positive terminal plate in an open state and the first negative terminal plate connected to the negative terminal member, The battery located at the other end has the second negative electrode terminal plate in an open state and the second positive electrode terminal plate connected to the positive electrode terminal member. Battery module.

2. The battery module according to claim 1, The electrode terminal plates of the battery are directly welded together. Battery module.

3. The battery module according to claim 2, the positive electrode terminal plate is made of an aluminum plate, The negative electrode terminal plate is made of a copper plate, The positive electrode terminal plate of one battery and the negative electrode terminal plate of the other battery are directly ultrasonically welded together. Battery module.

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