JP2004063278A - Laminate-armored flat battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery improved in durability by enhancing sealing capability and heat dissipation capability of the battery covered with a laminate film. <P>SOLUTION: This laminate-armored flat battery is characterized by fixing thermally welding parts for catching an electrode terminal lead by pinching means formed on the upper and lower sides thereof. By fixing them with the pinching means, the sealing capability of the thermally welding part is improved, strength of an electrode can be increased by an anchor effect, and the battery service life can be extended. The battery is excellent as an battery for an automobile expected to be used for a long time in a vibrating condition, and required to feed large-capacity power. <P>COPYRIGHT: (C)2004,JPO

Description

【図面の簡単な説明】
【図１】図１Ａは、本発明に用いた電池の構造の代表的な一実施形態を模式的に表した概略斜視図であり、図１Ｂは、正極端子リード部近傍の断面図であり、図１Ｃは、正極端子リードの存在しない熱融着部近傍の断面図である。
【図２】図２は、本発明の電池の外観の他の例示であり、図２Ａは、電池両端部からそれぞれ正極端子リードと負極端子リードとが形成される形態を、図２Ｂは、電池の一端から正極端子リードと負極端子リードとが形成される形態を模式的に表した概略斜視図である。
【図３】図３は、挟掴部材による固定個所を示す図であり、図３Ａは、電極端子リードを有する熱融着部のみを挟掴手段によって固定した電池の正面図を示し、図３Ｂは、熱融着部の全てを挟掴手段によって固定した電池の正面図を示す。電極端子リードに設けた貫通孔の配置を示す図である。
【図４】図４は、挟掴手段の上下の正極端子リードが近傍の電池の断面図であり、図４Ａは、正極端子リードが存在する場合を、図４Ｂは、正極端子リードがない場合の断面図を示す。
【図５】図５は、正極端子リードをネジ止めした場合の電池の正極端子リード部近傍の平面図とその際使用される正極端子リードを示す図であり、図５Ａは正極端子リードの熱融着部中央に丸い欠損部を有する場合であり、図５Ｂは、正極端子リードの両端に欠損部を有する場合である。
【図６】本発明に係る電池モジュール構造の代表的な一実施形態を模式的に表した概略図であり、図６Ａは、該モジュールの正面図であり、図６Ｂはその側面図であり、図６Ｃは平面図である。
【図７】図７は、複数のラミネート外装扁平型電を挟掴手段によって固定した場合の正極端子リード近傍の断面図を示し、図７Ａは、１対の挟掴手段によって２つのラミネート外装扁平型電を固定した場合を、図７Ｂは、モジュールケースを介して複数のラミネート外装扁平型電を弾性部材で固定した場合を示す。
【図８】本発明に係る複合電池モジュール構造の代表的な一実施形態を模式的に表した概略図である。
【図９】本発明に係る複合電池モジュールを搭載した車両を模式的に表した概略図である。
【符号の説明】
１０…扁平型電池、２０…正極板、２１…正極集電体、２２…正極端子リード、２３…正極端子リード熱融着部、３０…セパレータ、４０…負極板、４２…負極端子リード、４３…負極端子リード熱融着部、５０，５０’…ラミネートフィルム、６０…接着層、７０、７０’…挟掴手段、７１…ネジ、８０…欠損部、９０…弾性部材、１００…電池モジュール、１１０…電池モジュールケース、１１１…電池モジュールケース底部、１１２…電池モジュールケース蓋体、１２０…正極端子、１２１…電極リード端子、１２２…正極用リード線、１３０…負極端子、１３１…電極リード端子、１３２…負極端子用リード線、１４０…スペーサ、１５０…バスバー、２００…複合組電池、２１０…外部正極端子部、２２０…外部負極端子部、２３０…電池モジュール正極端子連結板、２４０…電池モジュール負極端子連結板、２５０…連結板、２６０…固定ネジ、２７０…正極絶縁カバー２７０、２８０…負極絶縁カバー、３００…ハイブリッドカー。TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flat-type battery having a laminated exterior in which at least a part of the heat-sealed portion is held by a fixing member, and more specifically, to enhance the adhesiveness of the heat-sealed portion by holding the heat-sealed portion from the outside. The present invention also relates to a laminated exterior flat battery having improved sealing properties, a battery module including the battery, and a composite battery pack.
[Prior art]
In recent years, air pollution by automobile exhaust gas has become a global problem, and electric cars powered by electricity and hybrid cars that run with a combination of an engine and a motor have attracted attention and are installed in these. Development of batteries with high energy density and high power density occupies an important position in the industry. As a configuration of a battery for such an application, a wound power generating element is housed in a cylindrical case, or a wound power generating element or a flat electrode, a flat type power generating element in which a separator is laminated is a flat case. There is something stored in. Since these cylindrical or flat cases need to have strength, they need to be formed of a metal container, and there is a problem that weight reduction is not easy. Therefore, as a means for reducing the weight of the battery and achieving higher energy density and higher output, for example, a laminate film as disclosed in JP-A-11-224652 is used as an outer case, and the periphery thereof is sealed by heat sealing. There has been proposed a structure of a battery sealed.
[Problems to be solved by the invention]
However, in such a battery using a laminate sheet for the battery outer case, the sealing property may be impaired due to deformation due to external force or an increase in internal pressure due to a rise in battery temperature. In particular, when the battery is used by mounting it on an electric vehicle or a hybrid car, the battery temperature may rise to about 60 ° C. in some cases. At that time, the electrode terminal lead uses a large current at the time of charging and discharging, and thus may be about 30 ° C. higher than the battery temperature, reaching the softening point of the resin in the laminated film (about 90 ° C.). . In such a situation, the increase in the internal pressure of the battery impairs the sealing property particularly at the portion in contact with the electrode terminal leads. Therefore, in a battery using a laminate sheet for such a battery outer case, it is an important issue how to secure sealing performance equal to or higher than that of a metal case. Therefore, as a device for such a demand, Japanese Patent Application Laid-Open No. 2000-133218 discloses that the position corresponding to the heat-sealed portion of the electrode terminal lead is set at the position of the olefin-based adhesive layer containing the titanate-based coupling agent and the laminated film. Attempts have been made to improve the sealability by coating with a coating layer made of the same resin as the inner layer.
However, in the above invention, when used in a camera-integrated VTR, a mobile phone, a portable computer, or the like, or while the sealing property is maintained in the initial stage of battery production, vibration conditions when mounted on an electric vehicle or a hybrid car are considered. In the long-term reliability in the above, the sealing performance may be reduced.
On the other hand, in order to suppress the resistance of the electrode terminal leads, it is preferable to increase the area of the electrode terminal leads. However, if the area of the electrode terminal leads is increased, the heat-sealed portion of the laminate film with the electrode terminal leads also increases. In addition, it is difficult to ensure the sealing performance.
In addition, as described above, the electrode terminal lead temperature may reach the softening point of the coating resin during charge and discharge, and the electrode terminal lead and the coating resin may be covered by the difference in the coefficient of thermal expansion between the electrode terminal lead and the coating resin or the internal pressure of the battery. In some cases, peeling or gaps may occur on the resin bonding surface, and the sealing property may be reduced. Due to such a decrease in the sealing property, the electrolytic solution and its decomposition products seep out from the interface of the electrode terminal leads in the battery, and cause liquid leakage along the interface between the electrode terminal leads and the coating resin. Further, the permeated electrolyte or the like corrodes the electrode terminal leads and causes an increase in electric resistance, further causing the electrode terminal leads to generate more heat during large-current charging / discharging, resulting in a problem that the deterioration of the coating resin and the exterior material is accelerated.
In view of the above, the present invention has been made in view of the above-described problems of the related art. In a battery using a laminated film in which a polymer-metal composite is used as a battery exterior material, the reliability of the battery in terms of sealing performance is considered. It is an object of the present invention to provide a laminated exterior flat battery that can improve charge and discharge performance with a large current.
[Means for Solving the Problems]
As a result of a detailed study of the heat-sealed portion of the laminated external flat battery, it was found that the sealing property was improved when the heat-sealed portion sandwiching the electrode terminal lead was gripped by a fixing member, and the present invention was completed. That is, a laminated film composed of a polymer and a metal is heat-sealed, and a positive electrode plate, a separator and a negative electrode plate are laminated and a power generation element is sealed. A flat type battery sandwiched between heat-sealed portions and protruding to the outside, wherein at least the heat-sealed portion sandwiching the electrode terminal lead is fixed by holding means provided above and below the laminate. It is an exterior flat battery.
Also, a battery module characterized by being connected in series and / or parallel using at least two or more of the above-mentioned laminated exterior flat batteries, and being characterized in that at least two or more battery modules are connected in series and / or in parallel. And a vehicle equipped with the composite battery.
【The invention's effect】
According to the present invention, by fixing the heat-sealed portion of the electrode terminal lead by the laminate film with the holding member, the sealing property of the heat-sealed portion can be improved, and the strength of the electrode by the anchor effect can be increased. Battery life can be extended. INDUSTRIAL APPLICABILITY The battery of the present invention is expected to be used for a long period of time under vibration conditions, and is excellent as an automobile battery that requires a large-capacity power supply.
BEST MODE FOR CARRYING OUT THE INVENTION
The first aspect of the present invention has a configuration in which a polymer-metal composite laminated film is heat-sealed, and a power generating element in which a positive electrode plate, a separator, and a negative electrode plate are laminated is sealed,
An electrode terminal lead connected to each of the above-mentioned electrode plates is a flat battery protruding outside sandwiched between the heat-sealed portions, wherein at least a heat-sealed portion sandwiching the electrode terminal leads is provided above and below the heat-sealed portion. A laminated exterior flat battery characterized by being fixed by gripping means.
In a flat battery with a laminated exterior, the sealing property at the heat-sealed portion between the electrode terminal lead and the laminated film is a problem, but if the heat-sealed portion is physically fixed by means of clamping, simple and long-term sealing is ensured. Thus, battery life can be extended.
Hereinafter, an embodiment of a laminated exterior flat battery according to the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited to these embodiments, and can be implemented with appropriate changes within the scope of the present invention.
First, an example of a preferred embodiment of the battery according to the present invention will be described with reference to FIG. 1A is an external view of the battery, FIG. 1B is a cross-sectional view of the vicinity of a heat-sealed portion of the battery illustrated in FIG. 1A with a positive electrode terminal lead interposed therebetween, and FIG. FIG. 4 is a cross-sectional view of the vicinity of heat fusion at a portion where there is no terminal lead.
In the battery 10 according to the present invention, a power generating element in which the positive electrode plate 20, the separator 30, and the negative electrode plate 40 are laminated is heat-fused from above and below with two laminated films 50, 50 'combining a polymer and a metal. The positive electrode terminal lead 22 connected with the positive electrode plate 20 and the positive electrode current collector 21 and the negative electrode terminal lead 42 connected with the negative electrode plate 40 and the negative electrode current collector are heat-fused with the positive electrode terminal lead. The portion 23 has a structure protruding to the outside from the negative electrode terminal lead heat fusion portion 43, and the upper and lower gripping members 70, which are provided at the portions corresponding to the heat fusion portions 23 and 43 of the positive electrode terminal lead 22 and the negative electrode terminal lead 42, The heat-sealed portions 23 and 43 are fixed by screws 71. The method for heat-sealing the laminated film is not limited to the case where one circumference of the outer peripheral portion is heat-sealed by two laminated films as shown in FIG. For example, as shown in FIG. 2A, the battery element is housed using a bag-shaped laminate film, and only the open end portions may be thermally fused to project the positive terminal lead 22 and the negative terminal lead 42, respectively. As shown in FIG. 2B, the location where the positive electrode terminal lead 22 and the negative electrode terminal lead 42 are taken out may be further reduced to one.
On the other hand, the battery of the present invention preferably has a flat structure shown in FIGS. In the case of a round battery structure, it is difficult to improve the sealing properties at the locations where the positive and negative electrode lead terminals are taken out, and high energy density and high power density batteries mounted on electric vehicles and hybrid cars This is because it is difficult to secure long-term reliability of the sealing property of the lead terminal take-out site.
As the electrode of the present invention, a positive electrode capable of occluding and desorbing lithium ions and a negative electrode capable of occluding and desorbing lithium ions are used, and a power generating element other than the electrodes includes a separator and an electrolytic solution impregnated in the separator or solid. An electrolyte or gel electrolyte, or a solid or gel electrolyte including a separator is used. As the positive electrode, the negative electrode, the separator, the electrolytic solution and the like, conventionally known ones can be used. For example, LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ It is desirable to use a negative electrode active material mainly composed of graphite or hard carbon that is amorphous carbon for the positive electrode active material mainly composed of, and the negative electrode is not particularly limited. Note that the positive electrode includes a positive electrode current collector and a positive electrode terminal lead attached to the tip of the positive electrode current collector. The positive electrode plate refers to a reaction part having a positive electrode active material in a positive electrode current collector. Similarly, the negative electrode includes a negative electrode current collector and a negative electrode terminal lead attached to the tip of the negative electrode current collector. The negative electrode plate refers to a reaction part including a negative electrode active material in a negative electrode current collector.
The separator, which is one of the essential elements of the power generation element of the present invention, is not particularly limited, and a conventionally known separator can be used. It should be noted that the separator of the present invention is not limited to its name, and may use a solid electrolyte or a gel electrolyte having a function as a separator instead of the separator. Some solid electrolyte batteries and gel electrolyte batteries to which the present invention can be applied include power generation by disposing a solid electrolyte or a gel electrolyte between a positive electrode active material layer of a positive electrode plate and a negative electrode active material layer of a negative electrode plate. This is because the element is housed in an exterior material made of a laminated film and is sealed by heat sealing the periphery. Further, the power generation element also contains the above-mentioned electrolyte solution or electrolyte as in the related art.
In the present invention, a power generating element in which a positive electrode plate, a separator, and a negative electrode plate are stacked has the same configuration as a conventional power generating element. For example, the positive electrode plate is formed by applying and drying the above-described positive electrode active material on one surface of the reaction portion of the positive electrode current collector, and the negative electrode plate is formed by applying and drying the above-described negative electrode active material on both surfaces of the reaction portion of the negative electrode current collector. The separator includes a polymer electrolyte sheet. Further, a positive electrode current collector is formed on the positive electrode plate, and a negative electrode current collector is formed on the negative electrode plate. These are joined to the positive electrode terminal lead and the negative electrode terminal lead by ultrasonic welding or the like. This joining may be performed by resistance welding. However, the power generating element of the present invention is not limited to these.
Further, in the present invention, a laminated film of a composite of a polymer and a metal is used as an exterior material. However, the film is not particularly limited, and a metal film is arranged between the polymer films and the whole is integrally laminated. Conventionally known products can be used. Generally, a heat-resistant insulating resin film made of a polymer film is laminated on both sides of a metal film layer, and when the film is the outermost layer of the laminate, it functions as an exterior protective layer. On the other hand, a heat-sealing insulating film made of a polymer film is further laminated on the heat-resistant insulating resin film as the innermost layer of the laminate. Such a laminated film is heat-sealed by an appropriate method, so that the heat-sealing insulating film portions are melted and joined to form a heat-sealed portion.
Examples of the metal film include an aluminum film. Examples of the insulating resin film include a polyethylene tetraphthalate film (heat-resistant insulating film), a nylon film (heat-resistant insulating film), a polyethylene film (heat-sealing insulating film), and a polypropylene film (heat-sealing insulating film). ) And the like. However, the exterior material of the present invention should not be limited to these. The laminate film can be easily and reliably joined by heat fusion of one to one (bag-shaped) laminate film utilizing a heat fusion insulating film by ultrasonic fusion or the like. In order to maximize the long-term reliability of the battery, metal films that are components of the laminate sheet may be directly joined to each other. Ultrasonic welding can be used to join the metal films by removing or destroying the heat-fusible resin between the metal films.
On the other hand, as the metal used for the terminal base material of the main material of the electrode terminal lead, a metal selected from Cu and Fe can be used, but a metal such as Al or stainless steel or an alloy material containing these can also be used. It is. It is desirable to use Cu for the terminal base material in order to suppress an increase in resistance of the entire electrode terminal lead, but there is no limitation. Ni is most preferably used for the surface coating layer, but metal materials such as Ag and Au can also be used. The surface coating layer may be provided on one or both of the positive electrode and the negative electrode of the electrode terminal lead. For example, among the metal materials used for the terminal base material of the electrode terminal lead, metals such as Al are used for the exterior material of the polymer, as is also used for the metal film material of the exterior material-metal composite laminate film. It can be said that the necessity of providing a surface coating layer is low because of good adhesion to the material. On the other hand, among the metal materials used for the terminal base material, metals such as Cu and Fe have relatively poor adhesion to the polymer material of the packaging material, and thus it can be said that the necessity of providing the surface coating layer is high. The metal such as Al is generally used for a terminal base material of a positive electrode terminal lead, and the metal such as Cu and Fe is generally used for a terminal base material of a negative electrode terminal lead. .
The present invention is characterized in that in such a laminated external flat battery, the heat-sealed portion is pressed by the gripping member and fixed so that the sealing property of the heat-sealed portion is improved. The fixing portion includes, as shown in FIG. 3A, at least a heat-sealed portion of the positive electrode terminal lead and the negative electrode terminal lead. As described above, the surface metal of the electrode terminal lead is aluminum or nickel metal, which is inferior in heat-sealing property to the heat-sealing insulating film as compared with a substance other than metal, deteriorates sealing properties, and has vibration conditions. When used for an automobile that needs to supply a large current below, long-term sealing performance may not be secured. However, according to the present invention, it is possible to easily improve the sealing property by fixing by the gripping means, and the strength of the electrode is improved by the anchor effect. On the other hand, the sealing property of the heat-sealed portion is not limited to the heat-sealed portion of the positive electrode terminal lead or the negative electrode terminal lead, and in the present invention, regardless of whether the heat-sealed portion has the electrode terminal lead or not. It can be fixed by gripping means. The heat generated at the time of current supply may cause the electrolyte, which is one of the battery elements, to thermally expand or generate gas due to decomposition of the electrolyte solution, resulting in an increase in the battery capacity. The heat-sealed portion may be damaged by the internal pressure change caused by such a volume change. Therefore, in the present invention, it is preferable to fix all the heat-sealed portions on the outer periphery of the battery. FIG. 3B shows a front view of the battery in which all of the heat-sealed portions are fixed by the holding means.
It is not necessary that the upper and lower gripping means provided above and below the heat-sealed portion have the same shape. For example, as shown in FIGS. 3A and 3B, two or four rectangular flat plates are used at the upper part of the heat-sealing part, and the lower part is a gripping means composed of one flat plate of the same type as the battery. Is also good. FIG. 4A shows a case where the positive electrode terminal lead is provided in a cross-sectional view near the heat-fused portion of the positive electrode terminal lead when one flat plate is used in the lower part, and FIG. 4B shows a case where the positive electrode terminal lead does not exist.
The holding member is not particularly limited, but is preferably a flat plate made of metal or resin. This is because if the plate is a flat plate, a large area of the heat-sealed portion can be fixed at a time by gripping, and if it is made of metal or resin, it is easy to form a flat plate for gripping. At this time, the electrode terminal lead heat-sealed portion of the battery also has irregularities due to a portion sandwiching the electrode terminal lead and a place where the electrode terminal lead does not exist. In order to prevent the fixing effect from being reduced by such irregularities, for example, irregularities corresponding to the thickness of the heat-sealed portion may be provided in advance on the heat-sealing contact side of the gripping member. By using such a holding means, the thickness after the holding can be made uniform, and the sealing property can be further improved. FIG. 1B shows a case where the thickness after clamping is set to h1 by using clamping means having the same thickness at the top and bottom of the heat-sealed portion where the positive electrode terminal lead is present, and FIG. As a means, a case where the thickness is larger than that of the lower portion and the thickness after gripping is h2 is shown. In the present invention, it is preferable that h1 = h2 by adjusting the thickness of the member.
Examples of the metal used for the holding means include iron, aluminum, copper, stainless steel, and alloys thereof. Iron, aluminum and stainless steel are preferred from the standpoint of availability, and aluminum and stainless steel are preferred from corrosion resistance. Aluminum and stainless steel are preferably used from the viewpoint of weight reduction and strength.
As the resin, acrylonitrile styrene resin, epoxy resin, melamine resin, polycarbonate, diallyl terephthalate resin, polyethylene, phenol resin, polymethyl methacrylate, polyacetal, polypropylene, polystyrene, polytetrafluoroethylene, polyurethane, polyamide resin, silicon It is preferably at least one resin selected from a resin, a urea resin and an unsaturated polyester resin, and more preferably an olefin resin such as polyethylene and polypropylene. This is because it is excellent in cost, chemical resistance and long-term fixing.
The method of fixing the gripping member is not particularly limited as long as the sealing property can be secured by pressing the heat-sealed portion. It may be fixed from above and below with rivets or screws, or may be fixed with clips or the like. It is convenient to fix a plurality of locations at both ends of the holding member with screws or rivets.
In the present invention, the gripping member may be fixed so as not to penetrate the electrode terminal lead portion, or may penetrate. However, as described above, since the laminated film used for the heat-sealed portion includes a metal film layer in the inner layer, if a through hole for screwing is provided after the electrode terminal lead is heat-sealed, a metal screw or the like may be formed. The use of rivets may cause short circuit failure due to contact between the metal of the laminate film and the electrode terminal leads. Therefore, in the present invention, it is preferable that the electrode terminal lead has a defective portion through which a fixing member such as a rivet or a screw penetrates.
Such a defective portion of the electrode terminal lead corresponds to a place where screws or rivets are fixed. Since the electrode terminal lead can be applied to either the positive electrode terminal lead or the negative electrode terminal lead, a description will be given of the positive electrode terminal lead heat-fused portion. As shown in FIG. 5A, when the gripping member is fixed with three screws, and when the center of the heat-sealed portion of the positive electrode terminal lead is screwed, the screw is previously screwed to the positive electrode terminal lead to be used. Are provided. The diameter of the through hole is preferably larger than the diameter of the screw body that penetrates, and smaller than the diameter of the screw head. This is for preventing contact between the electrode terminal lead and the screw body, avoiding short-circuit failure, and securing the fixability. The through hole is not limited to a round shape, but may be an elliptical system, a positive direction, or a rectangle. At this time, as described above, the screw body and the electrode terminal lead are not in contact with each other, and the electrode terminal lead is fixed by the screw head.
Alternatively, a defective portion may be provided at both ends of the heat-sealed portion of the positive electrode terminal lead, and a screw may be passed through the defective portion and fixed. This embodiment is shown in FIG. 5B. The size and shape of the cutouts at both ends can be arbitrarily selected, but the size is such that the screw body and the electrode terminal lead are not in contact and the electrode terminal lead is fixed by the screw head. Although the above description has been made with reference to the positive electrode terminal lead, a favorable sealing property can be similarly secured for the negative electrode terminal lead.
Although the size of the laminated external flat battery of the present invention is not limited, the heat-sealed portion of the electrode terminal lead is 5 to 15 mm from the strength of the heat-sealed portion of the electrode terminal lead. If the thickness is less than 5 mm, moisture easily enters from the heat-sealed portion, which may shorten the life of the battery. Further, the thickness of the electrode terminal lead is preferably 500 μm or less. If the electrode terminal lead having a thickness of 500 μm or more is used, a bad seal may occur for a long period of about 10 years when used for an automobile. Furthermore, the maximum size of one side of the battery is preferably 200 mm or less. This is because, in the case of a battery using a laminate film for the exterior, since the exterior has no strength, when the thickness exceeds 200 mm, the battery is easily deformed by external stress.
In order to manufacture the flat battery with a laminated exterior according to the present invention, the laminated exterior is manufactured in the same manner as in the related art except that a positive electrode terminal lead and / or a negative electrode terminal lead having a screw body penetrating defective portion in the heat-sealing corresponding portion are used. A flat battery can be manufactured. When the electrode terminal lead is not fixed by a screw or the like, it is not necessary to use the electrode terminal lead having the above-mentioned defective portion. Thereafter, the heat-sealed portion is sandwiched from above and below by the holding means, and the upper and lower holding means are fixed by screws or rivets.
In the present invention, at least two or more of the above flat batteries can be connected in series and / or in parallel to form a battery module. FIG. 6A is a front view, FIG. 6B is a side sectional view, and FIG. 6C is a plan view of the battery module of the present invention. As shown in FIG. 6A, four flat batteries 10 are connected in parallel, and four flat batteries 10 arranged in parallel are further connected in series in a metal battery module case 110 to form a battery module 100. It can be. In the present invention, it is preferable to connect four in series. If four batteries are connected in series, the operating voltage of a single cell will vary, but if the operating voltage of a single cell is 3.5 V, it will be 14 V, which can be applied to the current 12 V power supply. In this case, the voltage becomes 42 V, which can be applied to the vehicle transmission system voltage in the future. If 96 pieces are connected in series, the current power supply voltage for EV and HEV can be applied. In particular, 42V is a voltage effective for practical use of electric valves, electric brakes, and the like. As described above, the use of a battery pack having a multiple of 4 facilitates selection of use. The positive electrode terminal 120 and the negative electrode terminal 130 of the battery module 100 provided on the lid on the upper part of the battery module case 110, and the electrode lead terminals 121 and 131 of each flat battery 10 are the positive electrode and the negative electrode terminal of the battery module 100. Are electrically connected using the lead wires 122 and 132. When connecting four flat batteries 10 in parallel, as shown in FIG. 6B, the electrode terminal leads 121 of each flat battery 10 are electrically connected using an appropriate connecting member such as a spacer 140. Just connect. Similarly, when connecting the four flat batteries 10 in parallel to each other, six more flat batteries 10 are connected to each other using a suitable connection member such as a bus bar 150 as shown in FIG. 6A. The electrode lead terminals 121 and 131 may be electrically connected sequentially. However, the battery module of the present invention is not limited to the one described here, and a conventionally known battery module can be appropriately used. The battery module may be provided with various measuring devices and control devices according to the intended use. For example, a voltage measuring connector for monitoring the battery voltage is provided on the cover on the upper side of the battery module case 110. However, there is no particular limitation, for example, such as the presence of a device.
When a battery module is formed by combining a plurality of laminated exterior flat batteries of the present invention, for example, two laminated exterior flat batteries may be fixed by a set of holding means. In particular, when one side of the laminated external flat battery is flat, the number of gripping means can be reduced, which is preferable. For example, as shown in FIG. 7A, the two heat-sealed portions are fixed by a pair of gripping means in a form in which the flat surfaces are bonded. Further, the holding means can be fixed using the battery module case 110. FIG. 7B shows three sets of back-to-back batteries each having a holding member adhered only to the upper portion of the heat-sealed portion, and holding the holding means one by one while holding an elastic member 90 such as a spring. 11 is a cross-sectional view showing a case where the battery packs are sequentially stored in the battery pack 111 and are fixed from above by the battery module case lid 112 via the elastic member 90. In this case, individual fixing with screws, rivets, or the like is unnecessary. In addition, after manufacturing a flat-type battery with a laminated exterior similarly to the related art, if a conventionally known adhesive is used, the holding member can be easily attached, and the holding member can be fixed at the same time when the module 100 is assembled. Easy to manufacture. The elastic member 90 and the holding member 70 may be fixed using an adhesive. The elastic member includes an elastic elastomer in addition to the spring.
Next, by connecting at least two or more of the above-described battery modules in series, parallel or series-parallel to form a composite battery pack, a new battery module can be manufactured to meet the requirements for battery capacity and output for each purpose of use. And it is possible to respond relatively inexpensively. As shown in FIG. 8, for example, as shown in FIG. 8, in order to connect six sets of the battery modules 100 in parallel to form a combined battery 200, the battery modules 100 are provided on a lid above each battery module case 110. The positive terminal 120 and the negative terminal 130 of the battery module 100 are electrically connected using a battery module positive terminal connecting plate 230 and a battery module negative terminal connecting plate 240 having an external positive terminal 210 and an external negative terminal 220, respectively. I do. Further, in each screw hole (not shown) provided on both side surfaces of each battery module case 110, a connection plate 250 having an opening corresponding to the fixing screw hole is fixed with a fixing screw 260. Modules 100 are connected to each other. In addition, the positive electrode terminal 120 and the negative electrode terminal 130 of each battery module 100 are protected by positive and negative electrode insulating covers 270 and 280, respectively, and are identified by being classified into appropriate colors, for example, red and blue.
Further, by mounting the battery module and / or the composite battery pack on an electric vehicle or a hybrid car, it is possible to suppress heat generation of the electrode terminal leads at the time of large current discharge at the time of mounting, improve the life characteristics, and further improve the relatively long life. The above-mentioned problem of ensuring good sealing performance over a long period can be solved. For example, as shown in FIG. 9, it is convenient to mount the composite battery pack 200 under the seat in the center of the vehicle body of the electric vehicle or the hybrid car 300 because the interior space and the trunk room can be widened. However, the present invention is not limited to these, and may be mounted at the lower part of the rear trunk room, or if the engine is not mounted like an electric vehicle, the engine at the front of the vehicle body is mounted. It can also be mounted on parts that were used. In the present invention, depending on the intended use, not only the composite battery pack 200 but also a battery module may be mounted, or a combination of these battery modules and the composite battery pack may be mounted. Further, as the vehicle on which the battery module and / or composite battery pack of the present invention can be mounted, the above-described electric vehicle or hybrid car is preferable, but is not limited thereto.
【Example】
Hereinafter, the present invention will be described based on specific examples.
Example 1
Using a laminated film in which the heat-sealing insulating film layer was made of polypropylene and the metal film layer was made of aluminum, a laminated exterior flat battery having a width of 100 mm, a length of 150 mm and a thickness of 4 mm was manufactured. The electrode has LiMn that can occlude and desorb lithium ions. ₂ O ₄ A positive electrode using a positive electrode active material and a negative electrode using an amorphous carbon negative electrode active material capable of inserting and extracting lithium ions were used. An Al plate having a thickness of 150 μm was used for the positive electrode terminal lead. Used a 150 μm Ni plate. Each of the positive electrode terminal lead and the negative electrode terminal lead had a width of 50 mm and a length of 40 mm, and a single φ5 mm defect was provided at a position 10 mm from the current collector side. An acrylic plate having a width of 100 mm, a length of 10 mm, and a thickness of 3 mm was placed above and below electrode terminal leads of the battery, and was fixed at three places with screws through the above-mentioned defective portions to produce the battery shown in FIG. 1A.
Example 2
A laminated flat battery was manufactured in the same manner as in Example 1 except that all of the heat-sealed portions were fixed by the same type of upper and lower gripping means.
Example 3
A battery was manufactured in the same manner as in Example 1, except that an electrode terminal lead having a width of 50 mm, a length of 40 mm, and a thickness of 600 µm was used.
Example 4
A battery was manufactured in the same manner as in Example 2, except that an electrode terminal lead having a width of 70 mm, a length of 40 mm and a thickness of 600 µm was used.
Example 5: Characteristic evaluation 3: Leaving test at 40 ° C. for 60 days
The flat automobile batteries of Examples 1 to 4 were allowed to stand in an atmosphere of 40 ° C. for 60 days, and thereafter, the presence or absence of battery leakage was checked. Table 1 shows the test results.
[Table 1]

[Brief description of the drawings]
FIG. 1A is a schematic perspective view schematically showing a typical embodiment of the structure of a battery used in the present invention, and FIG. 1B is a cross-sectional view near a positive electrode terminal lead portion; FIG. 1C is a cross-sectional view of the vicinity of the heat-sealed portion where no positive electrode terminal lead exists.
FIG. 2 is another example of the appearance of the battery of the present invention. FIG. 2A shows a form in which a positive terminal lead and a negative terminal lead are formed from both ends of the battery, respectively, and FIG. FIG. 3 is a schematic perspective view schematically showing a form in which a positive electrode terminal lead and a negative electrode terminal lead are formed from one end.
FIG. 3 is a view showing a fixing portion by a gripping member. FIG. 3A is a front view of a battery in which only a heat-sealed portion having an electrode terminal lead is fixed by a gripping means; Fig. 2 shows a front view of the battery in which all of the heat-sealed portions are fixed by the holding means. It is a figure showing arrangement of a penetration hole provided in an electrode terminal lead.
4 is a cross-sectional view of the battery near the upper and lower positive terminal leads of the gripping means. FIG. 4A shows the case where the positive terminal lead exists, and FIG. 4B shows the case where the positive terminal terminal does not exist. FIG.
FIG. 5 is a plan view showing the vicinity of a positive terminal lead portion of a battery when the positive terminal lead is screwed, and a diagram showing a positive terminal lead used at that time. FIG. FIG. 5B shows a case where there is a round defect in the center of the fused portion, and FIG. 5B shows a case where there is a defect at both ends of the positive electrode terminal lead.
FIG. 6 is a schematic diagram schematically showing a typical embodiment of a battery module structure according to the present invention, FIG. 6A is a front view of the module, FIG. 6B is a side view thereof, FIG. 6C is a plan view.
FIG. 7 is a cross-sectional view showing the vicinity of a positive electrode terminal lead when a plurality of laminated exterior flat batteries are fixed by a gripping means. FIG. 7A is a cross-sectional view of two laminated exterior flat batteries by a pair of gripping means. FIG. 7B shows a case in which the static electricity is fixed, and FIG. 7B shows a case in which a plurality of laminated exterior flat type electricity is fixed with an elastic member via a module case.
FIG. 8 is a schematic diagram schematically showing a representative embodiment of the composite battery module structure according to the present invention.
FIG. 9 is a schematic diagram schematically showing a vehicle equipped with the composite battery module according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Flat battery, 20 ... Positive electrode plate, 21 ... Positive electrode collector, 22 ... Positive electrode terminal lead, 23 ... Positive terminal lead heat fusion part, 30 ... Separator, 40 ... Negative electrode plate, 42 ... Negative electrode terminal lead, 43 ... negative electrode terminal lead heat-sealed part, 50, 50 '... laminated film, 60 ... adhesive layer, 70, 70' ... clamping means, 71 ... screw, 80 ... defective part, 90 ... elastic member, 100 ... battery module, 110 ... battery module case, 111 ... battery module case bottom, 112 ... battery module case lid, 120 ... positive electrode terminal, 121 ... electrode lead terminal, 122 ... positive electrode lead wire, 130 ... negative electrode terminal, 131 ... electrode lead terminal 132: Lead wire for negative terminal, 140: Spacer, 150: Bus bar, 200: Composite battery, 210: External positive terminal, 220: External negative terminal, 230 Battery module positive terminal connecting plate, 240 ... battery module negative terminal connecting plate, 250 ... connecting plate, 260 ... fixing screws, 270 ... cathode insulating cover 270, 280 ... negative electrode insulating cover, 300 ... hybrid cars.

Claims (9)

Polymer-metal composite laminate film is heat-sealed, and has a configuration in which a power generating element in which a positive electrode plate, a separator and a negative electrode plate are laminated is sealed,
An electrode terminal lead connected to each of the electrode plates is a flat battery protruding outside sandwiched between the heat-sealed portions,
A flat battery with a laminated exterior, characterized in that at least a heat-sealed portion sandwiching at least the electrode terminal lead is fixed by gripping means provided on the upper and lower sides thereof. The flat battery with a laminated exterior according to claim 1, wherein the gripping member is made of metal or resin. The flat battery with a laminated exterior according to claim 2, wherein the fixing of the holding member is a rivet or a screw. The flat battery with a laminated exterior according to claim 3, wherein the electrode terminal lead has a defective portion through which the rivet or the screw penetrates. The resin is an acrylonitrile styrene resin, an epoxy resin, a melamine resin, a polycarbonate, a diallyl terephthalate resin, a polyethylene, a phenol resin, a polymethyl methacrylate, a polyacetal, a polypropylene, a polystyrene, a polytetrafluoroethylene, a polyurethane, a polyamide, a silicon resin, and urea. The flat battery with a laminated exterior according to any one of claims 2 to 4, wherein the battery is at least one resin selected from a resin and an unsaturated polyester resin. The laminated battery according to any one of claims 2 to 4, wherein the metal is iron, aluminum, copper, stainless steel, or an alloy thereof. A battery module comprising at least two or more laminated flat batteries according to claims 1 to 6 connected in series and / or in parallel. A composite battery module comprising at least two battery modules according to claim 7 connected in series and / or in parallel. A vehicle equipped with the composite battery according to claim 8.

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