JP2007273392A - Lid of battery case - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lid of a battery case capable of preventing deformation by reducing stress due to thermal contraction of a resin. <P>SOLUTION: The lid comprises a main body part 11 corresponding to the shape of an opening part, a set of electrode terminals 12 and 13, and insulating sealing members 141 and 142, and has an organic compound layer bonded by covalent bond at the portion where the electrode terminals 12 and 13 and the main body part 11 are jointed to the insulating sealing members 141 and 142. Then, the lid has a reinforcing portion extending in major axis direction at the jointing portion of the main body part 11 and the insulating sealing members 141 and 142 and has reinforcement members (electrode terminal) 12 and 13 jointed to the insulating sealing members 141 and 142. That is, by having the reinforcement member with reinforcing portion extending in major axis direction at the jointing portion between the insulating sealing member and the main body part, stress is made small. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a battery case lid, and more particularly to a battery case lid in a rectangular battery.

  As shown in FIG. 5, the battery case lid in the prior art is a member that closes the opening of the bottomed cylindrical case 92, and a pair of electrode terminals 912 connected to each electrode (not shown). And 913 of the electric double layer capacitor including 913 (Patent Document 1).

The lid 91 of the battery case is provided with a hollow cylindrical first electrode terminal 912 disposed on the outer peripheral side of the opening and a predetermined interval on the inner peripheral side of the electrode terminal 912. A second electrode terminal 913 and an insulating sealing member 914 made of a resin molded body including a small piece of glass fiber insert-molded between the electrode terminals 912 and 913 are provided. An organic compound layer chemically bonded to each electrode terminal 912 and 913 is formed on the surface of both electrode terminals 912 and 913. The insulating sealing member 914 is chemically bonded to the organic compound layer. The organic compound layer is made of a silane coupling agent or a triazine thiol derivative.
JP 2002-237436 A

  However, in the lid disclosed in Patent Document 1, since the electrode terminal and the resin are firmly bonded via the organic compound layer, the insulating sealing member made of resin formed by insert molding or the like is cooled and solidified. There is a problem that warpage deformation of the lid body occurs due to contraction at the time of welding, and a defect occurs in welding of the lid body and the case. In particular, when the shape of the lid is a square shape, since the bending strength of the lid is low, there is a problem that the amount of warp deformation of the lid further increases. In addition, even if warping deformation does not occur, a large stress is applied to the lid, and there is a possibility that an effect such as a decrease in sealing performance after long-term use may occur.

  The present invention has been completed in view of the above circumstances, and it is a problem to be solved to provide a battery case lid that can prevent the occurrence of warping deformation by reducing internal stress caused by thermal contraction of resin. And

The lid of the battery case of the present invention is a lid of a battery case that closes the opening of the battery case main body part in which the electrode body having the positive and negative electrodes and the electrolyte are partially opened, and
A main body having an outer shape generally corresponding to the opening, and formed of a metal plate;
A set of electrode terminals connected to the positive and negative electrodes of the electrode body;
An insulating sealing member that joins between the body portion and the electrode terminal by filling between the body portion and the electrode terminal and insulates between the pair of electrode terminals;
The portion where the one set of electrode terminals or the main body is joined to the insulating sealing member is covalently coupled to both the insulating sealing member and the one set of electrode terminals or the main body. It has an organic compound layer.

  The battery case lid of the present invention that solves the above-described problem has a reinforcing portion extending in the longitudinal direction at the joint portion of the main body portion and the insulating sealing member, and the reinforcing member joined to the insulating sealing member. It is characterized by having. Here, it is desirable that the length of the reinforcing member in the major axis direction of the main body is 60% or more of the length of the insulating sealing member.

  That is, if the area of the joint portion between the insulating sealing member and the main body is large (long), the influence on the main body due to the shrinkage of the resin forming the insulating sealing member becomes large, so the main body is reinforced. The reinforcement member is provided. Since the reinforcing member is joined to the insulating sealing member, it can resist the stress when the insulating sealing member contracts.

  The reinforcing member is a member having a reinforcing portion having a shape extending in a major axis direction of a portion where the main body portion and the insulating sealing member are joined. Here, the major axis direction of the joint portion is a direction including the longest portion in the spreading direction of the main body portion in the joint portion between the two. When the shape is an ellipse, the direction is the long axis, and when the shape is a rectangle, the direction is the long side or diagonal direction.

  The reinforcing member can also serve as the electrode terminal. By using both, the number of parts can be reduced.

  For the purpose of improving the bending strength, the main body part preferably has reinforcing ribs disposed on the outer peripheral part.

  Here, non-reinforced PPS or PP can be adopted as the insulating sealing member. Further, a triazine dithiol polymerized film can be adopted as the organic compound layer.

  Such distortion of the lid is remarkable when the shape of the opening is an elongated shape, and it is desirable to apply to such a lid.

  The lid of the battery case according to the present invention has the above-described configuration, and exhibits the following effects. That is, the lid of the battery case of the present invention can reduce the distortion generated by the shrinkage that occurs when the insulating sealing member is formed.

  The lid of the battery case of the present invention will be described in detail based on the following embodiments. The lid of the battery case of this embodiment is a member that closes the opening of the battery case main body. The battery case is a member that accommodates an electrode body and an electrolyte therein, and includes a battery case main body part that is partially opened to accommodate the electrode body and electrolyte, and a lid body that closes the opening part. The opening of the battery case body needs to be closed when the battery is used, but especially when the battery is a non-aqueous battery, it is required to improve the hermeticity in order to prevent moisture from entering. It is desirable to employ the battery case lid of the embodiment. The battery case body is preferably formed from metal.

  The lid of the battery case of the present embodiment has a main body portion, electrode terminals, and a reinforcing member. An insulating sealing member is filled between the main body portion and the electrode terminal. Further, the reinforcing member is joined to the insulating sealing member. The main body is formed from a metal plate. The shape of the main body has an outer shape that substantially corresponds to the opening of the battery case main body. After the main body is fitted into the opening, it can be joined by welding or the like. Like a prismatic battery, when the shape of the opening of the battery case main body is an elongated shape, there is a high risk of the cover body being distorted, so the effect of applying the battery case cover body of this embodiment is high.

  It is desirable that the main body portion is formed with ribs. The rib is preferably formed on the outer peripheral portion of the main body. The ribs on the outer peripheral portion can be easily formed by bending the outer peripheral portion of the main body by a method such as press working.

  The electrode terminal is connected to the positive and negative electrodes of the electrode body housed in the battery case, and includes one set of a positive electrode terminal connected to the positive electrode and a negative electrode terminal connected to the negative electrode. It is a member. Here, one of the positive electrode side and the negative electrode side can be shared by the aforementioned main body.

  The insulating sealing member is filled and formed between the main body portion and the electrode terminal. The insulating sealing member is a member that seals the inside of the battery case by insulating between a pair of electrode terminals and closely contacting the electrode terminals and the main body. The insulating sealing member can be formed by insert molding in a state where the main body portion and the electrode terminal are held at predetermined positions.

  An organic compound layer is formed between the main body or electrode terminal and the insulating sealing member. The organic compound layer is bonded by covalent bond between both the main body portion or the electrode terminal and the portion to be joined to the insulating sealing member.

  As an organic compound which forms an organic compound layer, a triazine thiol derivative or a silane coupling agent can be illustrated. These organic compounds form an organic compound layer at the portion where the main body and the insulating sealing member of the electrode terminal are joined. In particular, it is desirable to employ triazine thiols, and it is desirable to employ triazine dithiols.

  Examples of triazine thiol derivatives include 1,3,5-triazine-2,4,6-trithiol, 1,3,5-triazine-2,4,6-trithiol monosodium, and 1,3,5-triazine-2. , 4,6-trithiol-triethanolamine, 1,3,5-triazine-2,4,6-trithiol-di (tetrabutylammonium salt), 6-anilino-1,3,5-triazine-2,4 -Dithiol, 6-anilino-1,3,5-triazine-2,4-dithiol, monosodium, 6-dibutylamino-1,3,5-triazine-2,4-dithiol, 6-dibutylamino-1 , 3,5-triazine-2,4-dithiol monosodium, 6-dibutylamino-1,3,5-triazine-2,4-dithiol di (tetrabutyladiene Monium salt, 6-diallylamino-1,3,5-triazine-2,4-dithiol, 6-diallylamino-1,3,5-triazine-2,4-dithiol monosodium, 6-dithiooctylamino- 1,3,5-triazine-2,4-dithiol, 6-dithiooctylamino-1,3,5-triazine-2,4-dithiol monosodium, 6-dilaurylamino-1,3,5-triazine -2,4-dithiol, 6-dilaurylamino-1,3,5-triazine-2,4-dithiol monosodium, 6-stearylamino-1,3,5-triazine-2,4-dithiol, 6 -Stearylamino-1,3,5-triazine-2,4-dithiol monopotassium, 6-oleylamino-1,3,5-triazine-2,4-dithiol, - it can be exemplified Oreiruamino 1,3,5-triazine-2,4-dithiol-compounds such as monopotassium.

  Formation of an organic compound layer made of a triazine thiol derivative on the surface of the main body and the electrode terminal can be performed by electrodeposition. Specifically, an aqueous solution of these triazine thiol derivatives is used as an electrodeposition solution, and the member that forms the organic compound layer of the main body and electrode terminals is an anode, a platinum plate, a titanium plate, a carbon plate, etc. as a cathode. The electrodeposition process is performed at a low temperature by passing a current between both electrodes.

  As silane coupling agents, vinyltriethoxysilane, vinyltris (2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxy) (Cyclohexyl) ethyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, N -Phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, N-imidazolemethyltrimethoxysilane, N-imidazolemethyltriethoxysilane, 2- (N-imidazole) ) Ethyltrimethoxysilane, 2- (N-imidazole) ethyltriethoxysilane, 3- (N-imidazole) propyltrimethoxysilane, 3- (N-imidazole) propyltriethoxysilane, N-2-methylimidazolemethyltri Examples include methoxysilane, N-2-isopropylimidazolemethyltrimethoxysilane, N-2-ethyl-4-methylimidazolemethyltrimethoxysilane, and the like. Moreover, Palcoat 3751 (brand name), Palcoat 3841 (brand name) by Nippon Parkerizing Co., Ltd., etc. can be used as a commercially available chemical | medical agent of silane coupling agent aqueous solution. In particular, the imidazole silane compound has high heat resistance and can maintain good adhesion.

  In order to form an organic compound layer composed of a silane coupling agent on the surface of the main body and the electrode terminal, the surface of the main body and the electrode terminal is washed and dried, and then in a silane coupling agent aqueous solution at room temperature for several seconds to several minutes. Immerse. And after pulling up from a silane coupling agent aqueous solution, an organic compound layer can be formed by making it dry without washing with water.

  For the main body and the electrode terminal, aluminum, aluminum alloy, copper, stainless steel, iron, nickel, titanium, tantalum, or the like can be used to form a covalent bond with the silane coupling agent or the triazine thiol derivative. In particular, it is preferable to use aluminum or an aluminum alloy because of its excellent affinity with the triazine thiol derivative and the silane coupling agent.

  Insulating sealing members include polyolefins such as polypropylene (PP), nylon, acrylonitrile-butadiene-styrene copolymer resin (ABS), polybutylene to form a covalent bond with a triazine thiol derivative or a silane coupling agent. Terephthalate (PBT), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), epoxy resin, phenol resin, or the like can be used. In particular, PPS and PP can be preferably used because of excellent bondability with the organic compound layer. Furthermore, it is desirable to employ a non-reinforced resin not containing a filler (for example, non-reinforced PPS or non-reinforced PP). This is because the filler formed from glass or the like may react with the electrolyte.

  The reinforcing member is a member that suppresses the bending of the main body against the stress accompanying the contraction that occurs when the insulating sealing member cools. The reinforcing member has a reinforcing portion extending in the long axis direction at the joint portion of the main body portion and the insulating sealing member. For example, the reinforcing portion is composed of a plate-like member or a rod-like member. The reinforcing member is joined to the insulating sealing member. In particular, it is desirable that the reinforcing portion is joined to the insulating sealing member. Here, it is desirable that the length of the reinforcing member is 60% or more of the length of the insulating sealing member in the major axis direction of the portion where the insulating sealing member and the main body are joined.

  The reinforcing member can also serve as the electrode terminal described above. This can be realized by processing the electrode terminal so that a part of the electrode terminal is disposed along the surface of the main body.

  Hereinafter, the lid of the battery case of the present invention will be described in detail based on examples. As shown in FIGS. 1 and 2, the battery case lid 1 of the present embodiment includes a main body 11, an electrode terminal (positive electrode terminal) 12, an electrode terminal (negative electrode terminal) 13, and insulating sealing members 141 and 142. Have. The lid 1 of the battery case is fitted into the opening of the battery case main body 2 and joined (for example, joined by welding) to form a sealed battery case. The electrode terminals 12 and 13 are electrically connected to positive and negative electrodes of an electrode body (not shown).

  The main body 11 is made of an aluminum plate and has through holes 11a and 11b through which the electrode terminals 12 and 13 pass. The electrode terminals 12 and 13 are disposed in the through holes 11 a and 11 b so as not to contact the main body 11. The electrode terminals 12 and 13 also serve as a reinforcing member. That is, as shown in FIGS. 2 and 3, the electrode terminals 12 and 13 are formed in the major axis direction of the shape of the joint portion of the main body portion 11 and the insulating sealing members 141 and 142 (in the left-right direction of the drawing, the opening portion of the battery case main body portion 2). A portion extending in the longitudinal direction). Since the electrode terminals (reinforcing members) 12 and 13 have portions extending in the major axis direction, it is possible to resist stress when the insulating sealing members 141 and 142 contract. Insulating sealing members 141 and 142 made of PP or PPS are filled / formed between the body 11 and the electrode terminals 12 and 13 for the purpose of maintaining the positional relationship and sealing / joining the two. Has been.

  The surface of the main body 11 and the electrode terminals 12 and 13 has an organic compound layer composed of triazinedithiol. This organic compound layer is a triazine dithiol polymerized film. Specifically, the main body part 11 and the electrode terminals 12 and 13 are immersed in a triazine dithiol aqueous solution as a cathode, and a triazine dithiol polymerized film is formed by flowing an electric current using platinum or the like as an anode.

  The insulating sealing members 141 and 142 are formed by performing insert molding in a state where the main body 11 and the electrode terminals 12 and 13 are arranged at predetermined positions. By performing insert molding, a reaction that forms a covalent bond with the organic compound layer formed on the surface of the main body 11 and the electrode terminals 12 and 13 proceeds, and the insulating sealing members 141 and 142 11 and the electrode terminals 12 and 13 are firmly joined.

  Here, as is apparent from the cross-sectional view shown in FIG. 2, the shape of the insulating sealing members 141 and 142 is divided into two in the spreading direction of the main body 11 (the left-right direction in FIG. 2). Further, the insulating sealing members 141 and 142 are formed so that the front and back surfaces of the main body 11 have joint surfaces having substantially the same shape.

  By adopting the form as described above as the shape of the insulating sealing members 141 and 142, the stress applied to the main body 11 after insert molding is reduced. That is, since the electrode terminals 12 and 13 have the insulating sealing members 141 and 142 and the portion extending in the major axis direction of the joint portion of the main body 11, the stress due to the contraction of the insulating sealing members 141 and 142 can be resisted. Then, by dividing the insulating sealing member into two parts and reducing the size of the main body 11 in the spreading direction, the stress applied to the joint surface in each of the insulating sealing members 141 and 142 is reduced. Moreover, by making the joint surface the same shape on the front and back surfaces, the stress cancels out on the front and back surfaces, and the stress in the direction of bending the main body 11 can be reduced.

  FIG. 4 shows other battery case lids. The battery case lid 1 ′ shown in FIG. 4 has different electrode terminals 12 ′ and 13 ′. That is, the portion passing through the main body portion 11 ′ is cylindrical, and has reinforcing portions 121 and 131 disposed substantially parallel to the main body portion 11 ′ in the vicinity of the bottom portion. The reinforcing portions 121 and 131 relieve stress due to the shrinkage of the insulating sealing members 141 and 142.

It is an external view of the battery provided with the cover of the battery case of a present Example. It is sectional drawing of the battery provided with the cover body of the battery case of a present Example. It is a top view of the cover body of the battery case of a present Example. It is sectional drawing of the battery provided with the cover body of the battery case of another Example. It is sectional drawing of the battery provided with the cover body of the battery case of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 91, 91 ', 91 "... Lid of battery case 11 ... Main-body part 11a, 11b ... Through-hole 12, 13, 912, 913 ... Electrode 141, 142, 143, 144, 914 ... Insulation sealing member 2 ... Battery Case body

Claims (7)

An electrode body having positive and negative electrodes and a battery case lid for closing the opening of the battery case main body part in which the electrolyte is accommodated.
A main body having an outer shape generally corresponding to the opening, and formed of a metal plate;
A set of electrode terminals connected to the positive and negative electrodes of the electrode body;
An insulating sealing member that joins between the body portion and the electrode terminal by filling between the body portion and the electrode terminal and insulates between the pair of electrode terminals;
The portion where the one set of electrode terminals or the main body is joined to the insulating sealing member is covalently coupled to both the insulating sealing member and the one set of electrode terminals or the main body. Has an organic compound layer,
A battery case lid having a reinforcing portion extending in a major axis direction at a joint portion of the main body portion and the insulating sealing member and having a reinforcing member joined to the insulating sealing member.   The battery case lid according to claim 1, wherein a length of the reinforcing member in a major axis direction of the main body is 60% or more of a length of the insulating sealing member.   The battery case lid according to claim 1, wherein the reinforcing member also serves as the electrode terminal.   The battery body lid according to claim 1, wherein the main body portion has reinforcing ribs disposed on an outer peripheral portion.   The battery case lid according to claim 1, wherein the insulating sealing member is non-reinforced PPS or PP.   The battery case cover according to claim 1, wherein the organic compound layer is a triazine dithiol polymerized film.   The battery case lid according to any one of claims 1 to 6, wherein the shape of the opening is an elongated shape.

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