Heat insulating reinforcement material for battery pack cover and battery pack

Abstract

To provide a heat insulating reinforcement material for a battery pack cover that exhibits favorable heat insulating properties and can effectively suppress damage to various components even when an abnormality occurs in a secondary battery cell that constitutes a storage module.SOLUTION: In an insulating reinforcement material for a cover that is placed inside the cover of a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, one or more inorganic fiber-containing layers and one or more metal plate layers are stacked together.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a heat insulating reinforcement material for a battery pack cover and a battery pack. [Background technology]

[0002] 2. Description of the Related Art Conventionally, electric vehicles that run using an electric motor and hybrid vehicles that run using both an engine and an electric motor are equipped with a power storage module (battery assembly) as a drive source for the electric motor. In the above-mentioned energy storage module, a plurality of energy storage elements (secondary battery cells) having positive and negative electrode terminals are arranged, and the electrode terminals of adjacent secondary battery cells are connected by a bus bar to form a secondary battery cell string in which a plurality of secondary battery cells are connected in series. The secondary battery cell strings are arranged in multiple rows as necessary depending on output, etc.

[0003] In addition, a busbar module (connection module) that holds a busbar is typically attached to the top of the string of secondary battery cells that make up the energy storage module, and in a typical busbar module, a connection module cover is attached to insulate and protect the connection between the busbar and the electrode terminal (see, for example, Patent Document 1).

[0004] In an automotive battery system, one or more of the above-mentioned storage modules are placed and connected inside a case, and the system is operated in the form of a battery pack, which is equipped with protection circuits to prevent overcharging, over-discharging, or overheating of the storage module, a BMS (battery management system) to monitor voltage and temperature, as well as charge / discharge circuits and a cooling mechanism. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-125474 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, during operation of the power storage module, the battery pack and other components may be damaged due to overheating of the secondary battery cells that constitute the power storage module. For example, because lithium secondary batteries use organic electrolytes, overcharging the battery can induce overcurrent or overheating. If this leads to the battery emitting smoke, high-temperature gas and high-temperature molten particles (high-temperature molten particles resulting from electrode detachment and melting of the aluminum current collector) can be ejected and scattered, and the energy of this can cause a fire.

[0007] For this reason, it is necessary to prevent or suppress such fires as a safety measure for the battery pack; however, covers such as the upper cover (described below) that constitute the battery pack may be coated with cationic paint (anti-rust paint), and if they are exposed to heat from the inside, the painted surface may self-ignite, making it necessary to take insulation measures for the battery pack cover.

[0008] In addition, since it is possible that high-temperature molten particles erupting from the secondary battery cell may cause physical damage to the battery pack or various components provided on the outside of the battery pack, it was thought necessary to take damage prevention measures in addition to the above-mentioned insulation measures on the inside of the battery pack cover.

[0009] For this reason, for example, as shown in the schematic cross-sectional view of Figure 5(a), in a battery pack 11 in which multiple storage modules 12 are housed in the space formed between an upper cover 13 and a lower cover 15, a measure has been considered in which an insulating reinforcement material 14 is provided on the inner surface of the upper cover 13. As the above-mentioned insulating reinforcement material 14, as shown in the enlarged cross-sectional view of Figure 5(b), an example is a laminate consisting of an adhesive layer 14g1, a mica plate 14i, an adhesive layer 14g2 and a silica cloth 14r laminated in that order on the inside of the upper cover 13 in the direction from the inner surface of the upper cover 13 toward the lower cover 15. In the above-mentioned insulating reinforcement material 14, even if smoke is emitted or high-temperature particles are ejected from the storage module 12, the silica cloth 14r provides insulating properties to prevent the upper cover from catching fire, and it was thought that the mica plate 14i insulates the inside of the battery pack 11 and can also prevent physical damage even if an abnormality occurs in the secondary battery cell and high-temperature molten particles are ejected and scattered.

[0010] However, there are cases in which the insulating reinforcing material formed by laminating the silica cloth and mica plates does not necessarily provide sufficient protection against damage to the battery pack and the like.

[0011] In other words, in the case of battery packs installed in automobiles, as the energy density of batteries (secondary battery cells) increases in the future, it is conceivable that the secondary battery cells will be more likely to emit smoke or fire as described above, or to erupt or scatter high-temperature molten particles, making it impossible to fully prevent damage to the battery pack, etc., and therefore it is predicted that there will be an increasing demand for improved functionality as a measure against damage.

[0012] On the other hand, in recent years, with the reduction in the space in which in-vehicle devices are placed (space saving), there is a demand for downsizing of various in-vehicle devices, and even in the above-mentioned battery pack, the gap between the storage module 12 and the upper cover 13 is now only a few mm. In this case, it becomes difficult to provide a sufficient thickness for the insulating reinforcement material 14 arranged between the storage module 12 and the upper cover 13, and it is considered that damage to the battery pack 11 and various components provided on the outside of the battery pack 11 will be particularly likely to occur if smoke or fire, or high-temperature molten particles are emitted or scattered from the storage module 12.

[0013] Under these circumstances, the present invention aims to provide an insulating reinforcement material for a battery pack cover and a battery pack that exhibits suitable insulating properties and can effectively suppress damage to various components even if an abnormality occurs in a secondary battery cell that constitutes a storage module. [Means for solving the problem]

[0014] In order to achieve the above-mentioned object, the inventors conducted intensive research and discovered that the above-mentioned technical problems can be solved by an insulating reinforcement material for a cover that is placed inside the cover of a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, the insulating reinforcement material for a battery pack comprising one or more inorganic fiber-containing layers and one or more metal plate layers stacked together, and have completed the present invention based on this finding.

[0015] That is, the present invention provides (1) A heat insulating reinforcement member for a cover that is disposed on the inside of a cover of a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, the reinforcement member comprising: One or more inorganic fiber-containing layers and one or more metal plate layers are laminated. A heat insulating reinforcement material for a cover of a battery pack, (2) A battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, A cover insulating reinforcement material having one or more inorganic fiber-containing layers and one or more metal plate layers laminated thereon is provided on the inside of the cover of the battery pack. A battery pack comprising: This provides: In the following description, the "insulating reinforcement material for the battery pack cover" will be referred to as the "insulating reinforcement material" as appropriate. Effect of the Invention

[0016] According to the present invention, it is possible to provide an insulating reinforcement material for a battery pack cover and a battery pack that exhibit suitable insulating properties and can effectively suppress damage to various components even if an abnormality occurs in a secondary battery cell that constitutes a storage module. [Brief description of the drawings]

[0017] [Figure 1]1 is a schematic cross-sectional view of a battery pack and a heat insulating reinforcing material for explaining an example of the heat insulating reinforcing material according to the present invention; [Diagram 2] 1 is a schematic cross-sectional view of a battery pack and a heat insulating reinforcing material for explaining an example of the heat insulating reinforcing material according to the present invention; [Diagram 3] 1 is a schematic cross-sectional view of a battery pack and a heat insulating reinforcing material for explaining an example of the heat insulating reinforcing material according to the present invention; [Figure 4] 1 is a schematic cross-sectional view of a battery pack and a heat insulating reinforcing material for explaining an example of the heat insulating reinforcing material according to the present invention; [Diagram 5] 1 is a schematic cross-sectional view of a battery pack and a heat insulating reinforcement material that are used as a comparison with the battery pack and the heat insulating reinforcement material of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] First, a heat insulating reinforcing material for a battery pack cover according to the present invention will be described. The insulating reinforcement material for a battery pack cover according to the present invention comprises: A heat insulating reinforcement member for a cover is disposed on an inner side of a cover of a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, the reinforcement member comprising: One or more inorganic fiber-containing layers and one or more metal plate layers are laminated. It is characterized by the above.

[0019] Hereinafter, a heat insulating reinforcing material for a battery pack cover according to the present invention will be described with reference to the drawings as appropriate.

[0020] FIG. 1(a) is a schematic cross-sectional view of a battery pack for explaining an example of a heat insulating reinforcing material according to the present invention. As illustrated in Figure 1(a), a battery pack 1 to which the insulating reinforcement material of the present invention is applied houses one or more storage modules 2 within a case defined by an upper cover 3 and a lower cover 5.

[0021] The upper cover constituting the battery pack is preferably made of a metal material such as aluminum. The upper cover is also preferably coated with an anti-rust paint. An example of the anti-rust paint is cationic paint, and the entire surface of the upper cover is preferably coated with the paint.

[0022] The lower cover constituting the battery pack is preferably made of a metal material such as aluminum, similar to the upper cover. The lower cover is preferably coated with an anti-rust paint, similar to the upper cover. As the anti-rust paint, for example, cationic paint can be used, similar to the above, and the entire surface of the lower cover is preferably coated with the paint. After an item such as a power storage module is placed in the lower cover, the lower cover is attached to the upper cover to form a battery pack, as shown in the cross section of FIG. 1(a).

[0023] The power storage module (power storage module 2 illustrated in FIG. 1) disposed in the battery pack houses a plurality of secondary battery cells.

[0024] The form of the energy storage module is not particularly limited, and examples thereof include a secondary battery cell row in which a plurality of secondary battery cells, each having positive and negative electrode terminals, are arranged in series by connecting the electrode terminals of adjacent secondary battery cells with a bus bar, and the secondary battery cell row may be arranged in multiple rows.

[0025] The power storage module may be one in which a bus bar module (connection module) that holds a bus bar is attached to an upper portion of the string of secondary battery cells.

[0026] Furthermore, when multiple energy storage modules are arranged within a battery pack, it is preferable to arrange each energy storage module at a predetermined distance from each other. By arranging each energy storage module at a predetermined distance from each other, damage to adjacent energy storage modules can be suppressed in the event that a secondary battery cell constituting a storage module emits smoke or catches fire, or if high-temperature molten particles are ejected or scattered.

[0027] The storage module in the battery pack may have a gas exhaust port. The location of the gas exhaust port is not particularly limited, but for example, as shown in FIG. 1(a), each storage module 2 housed in the battery pack 1 may have a gas exhaust port 21 on the surface facing the upper cover 3.

[0028] Moreover, the lower cover constituting the battery pack is preferably provided with an opening for ventilation.

[0029] The heat insulating reinforcement material according to the present invention is disposed inside the cover of the battery pack, and is usually disposed in a fixed state inside the cover of the battery pack.

[0030] Specifically, as shown in the schematic cross-sectional diagram in FIG. 1(a), it is disposed inside the upper cover 3 constituting the battery pack 1 (on the inner surface of the upper cover 3) between the upper cover 3 and the energy storage module 2 as an insulating reinforcement material 4, and is usually disposed in a fixed state by adhering or the like to the inner surface of the upper cover 3.

[0031] In the embodiment shown in FIG. 1( a ), the heat insulating reinforcing material 4 is provided vertically above the gas exhaust port 21 provided in the electricity storage module 2 so as to face the gas exhaust port 21 .

[0032] 1(a) generates smoke or fire, or when high-temperature molten particles are ejected or scattered, most of the high-temperature gas, flare (flame), or high-temperature molten particles are ejected vertically upward from gas exhaust port 21 provided in power storage module 2. In battery pack 1 shown in FIG. 1(a), gas exhaust port 21 of power storage module 2 is provided on a surface facing upper cover 3, and therefore battery pack 1 is more susceptible to impact by high-temperature gas, flare, or high-temperature molten particles ejected from gas exhaust port 21 at upper cover 3 than at lower cover 5. In this case, as illustrated in FIG. 1(a), an insulating reinforcing material is disposed between the upper cover 3 and the energy storage module 2, vertically above the gas exhaust port 21 provided in the energy storage module 2, so as to face the gas exhaust port 21. This makes it easy to provide insulating and reinforcing properties (effects of suppressing the spread of fire to the outside of the battery pack and effect of suppressing the ejection and scattering of high-temperature molten particles) to the parts that are particularly subject to large impacts.

[0033] The insulating reinforcement material of the present invention is placed on the inside of the cover of the battery pack, and may be placed on the inside of the upper cover of the battery pack (on the inner surface side of the upper cover), or may be placed on the inside of the lower cover of the battery pack (on the inner surface side of the lower cover), or may be provided on both the inside of the upper cover and the inside of the lower cover of the battery pack.

[0034] The heat insulating reinforcing material according to the present invention is formed by laminating one or more inorganic fiber-containing layers and one or more metal plate layers.

[0035] In the insulating reinforcing material of the present invention, examples of the inorganic fiber-containing layer include those formed from components such as heat-resistant cloth (containing inorganic fibers), heat-resistant paper (containing inorganic fibers), rock wool, inorganic spray materials, inorganic mat materials, inorganic sheet materials, or inorganic board materials. The constituent material such as the heat-resistant cloth constituting the inorganic fiber-containing layer may be coated with a resin film (protective resin film) as a protective layer on at least a part of the surface.

[0036] In the heat insulating reinforcing material according to the present invention, the inorganic fiber-containing layer is preferably formed of a flexible component material. Since the inorganic fiber-containing layer is formed from a flexible component material, it can be suitably arranged while being adapted to conform to the shape of the inside of the cover on which it is to be installed.

[0037] In the heat insulating reinforcing material according to the present invention, examples of the heat resistant cloth include glass cloth, silica cloth, and alumina cloth.

[0038] In the heat insulating reinforcing material according to the present invention, the heat resistant paper may be a heat resistant inorganic paper, which is made by adding a small amount of organic binder to bulk inorganic fibers and processing them into a paper shape using a papermaking machine, and is flexible and can be easily folded and used. Examples of inorganic fibers constituting the heat-resistant inorganic paper include glass fibers, silica fibers, alumina fibers, mullite fibers, silicon carbide fibers, and rock wool. The organic binder constituting the heat-resistant inorganic paper may be one or more selected from acrylic resin, polyvinyl alcohol, and the like. Specific examples of heat-resistant inorganic paper include Fineflex BIO (registered trademark) paper (manufactured by Nichias Corporation) and Vermosal sheet (manufactured by Nichias Corporation).

[0039] In the heat insulating reinforcing material according to the present invention, when the constituent material of the inorganic fiber-containing layer has a protective resin film on at least a part of the surface, the resin film constituting the protective resin film may be, for example, one or more selected from PET (polyethylene terephthalate) film, PEN (polyethylene naphthalate) film, PBT (polybutylene terephthalate) film, nylon film, PEEK (polyether ether ketone) film, PPS (polyphenylene sulfide) film, etc. In terms of cost, the resin film is preferably a PET film. When the constituent material of the inorganic fiber-containing layer has a protective resin film on at least a part of the surface, the protective resin film is preferably attached by lamination or the like.

[0040] In the case where the heat insulating reinforcing material according to the present invention has two or more inorganic fiber-containing layers (two or more layers), the inorganic fiber-containing layers may be of the same type or of different types.

[0041] Since the insulating reinforcement material of the present invention has one or more inorganic fiber-containing layers, the insulating reinforcement material of the present invention can be easily imparted with the desired insulating properties, and heat conduction to the upper case that constitutes the battery pack can be easily suppressed.

[0042] In the heat insulating reinforcing material according to the present invention, the thickness of the inorganic fiber-containing layer is preferably 0.1 to 1.5 mm, more preferably 0.1 to 0.7 mm, and even more preferably 0.1 to 0.5 mm.

[0043] In the insulating reinforcement material of the present invention, since the thickness of the inorganic fiber-containing layer is within the above range, the desired insulation properties can be easily imparted to the battery pack in which the insulating reinforcement material of the present invention is placed.

[0044] In the present application, the thickness of the inorganic fiber-containing layer means the arithmetic average value of thicknesses measured at any five points of the inorganic fiber-containing layer using a micrometer.

[0045] The insulating reinforcement material of the present invention has one or more inorganic fiber-containing layers stacked in the direction from the inner surface of the upper cover to the lower cover, and can have, for example, a form in which a single inorganic fiber-containing layer 4R is stacked in the direction from the inner surface of the upper cover to the lower cover, as shown in the schematic cross-sectional diagrams of Figures 1(b) and 1(c) described below.

[0046] In the insulating reinforcement material of the present invention, the number of inorganic fiber-containing layers is not particularly limited, but a laminate of 1 to 6 inorganic fiber-containing layers in the direction from the inner surface of the upper cover to the lower cover is preferable, a laminate of 1 to 5 inorganic fiber-containing layers is more preferable, and a laminate of 1 to 4 inorganic fiber-containing layers is even more preferable. When the insulating reinforcing material of the present invention is a laminated arrangement of multiple inorganic fiber-containing layers, the inorganic fiber-containing layers may be laminated so as to be adjacent to each other, or may be laminated so as to be spaced apart from each other via a metal plate layer or the like.

[0047] In the heat insulating reinforcing material according to the present invention, the total thickness of the inorganic fiber-containing layers constituting the heat insulating reinforcing material is preferably 0.1 to 2.0 mm, more preferably 0.1 to 1.0 mm, and even more preferably 0.1 to 0.7 mm.

[0048] In addition, in this application document, the total thickness of the inorganic fiber-containing layers means the value obtained by determining the thickness of each heat-resistant cloth that constitutes the insulating reinforcement material of the present invention by the method described above and adding up the thicknesses of each inorganic fiber-containing layer obtained.

[0049] In the insulating reinforcement material of the present invention, by having the number of layers and the total thickness of the inorganic fiber-containing layers within the above-mentioned range, the overall thickness of the insulating reinforcement material of the present invention can be suppressed, while the desired insulation properties can be easily imparted to the battery pack in which the insulating reinforcement material of the present invention is placed.

[0050] In the heat insulating reinforcing material according to the present invention, examples of the metal plate constituting the metal plate layer include an iron plate and a stainless steel plate. In the insulating reinforcement material according to the present invention, when two or more metal plate layers (two or more layers) are formed, the metal plates constituting each metal plate layer may be of the same type or of different types.

[0051] In the heat insulating reinforcing material according to the present invention, the metal plate constituting the metal plate layer may be, for example, one having a surface sprayed with an electrically insulating ceramic. The electrically insulating ceramic may be one or more selected from aluminum oxide, zirconium oxide, zirconium silicate, and the like.

[0052] In the insulating reinforcement material of the present invention, by using a metal plate that constitutes the metal plate layer and that has an electrically insulating ceramic sprayed on its surface, electrical insulation can be easily imparted to the insulating reinforcement material of the present invention.

[0053] In the heat insulating reinforcing material according to the present invention, the metal plate constituting the metal plate layer is preferably made of a metal material having high ductility (for example, an iron plate, a stainless steel plate, etc.). By adopting a metal plate made of a highly ductile metal material as the metal plate constituting the metal plate layer, it is possible to easily form a heat insulating reinforcing material having reinforcing properties while suppressing the thickness of the metal plate layer. In addition, since metal plates are usually deformable and workable, the metal plate layer made of the above metal plate can be suitably arranged while following the inner shape of the cover to be installed by molding and processing it according to the inner shape of the cover to be installed, just like the inorganic fiber-containing layer formed of the above-mentioned flexible component material.

[0054] Because the insulating reinforcement material of the present invention has one or more metal plate layers, the desired reinforcement properties can be easily imparted to the insulating reinforcement material of the present invention, and even if an abnormality occurs such as high-temperature molten particles being ejected or scattered from a secondary battery cell that constitutes the energy storage module, the ejection and scattering of high-temperature molten particles from the inside of the battery pack to the outside can be effectively suppressed, thereby effectively suppressing damage to the battery pack or various components arranged on the outside of the battery pack.

[0055] In the heat insulating reinforcing material according to the present invention, the thickness of the metal plate layer is preferably 0.2 to 1.0 mm, more preferably 0.2 to 0.7 mm, and even more preferably 0.2 to 0.5 mm.

[0056] In the insulating reinforcement material of the present invention, since the thickness of the metal plate layer is within the above range, the battery pack in which the insulating reinforcement material of the present invention is placed can be easily imparted with the desired reinforcement properties (the effect of suppressing the ejection and scattering of high-temperature molten particles to the outside of the battery pack).

[0057] In the present application, the thickness of the metal plate layer refers to the arithmetic average value of thicknesses measured at any three positions of the metal plate layer using a micrometer.

[0058] The insulating reinforcement material of the present invention has one or more metal plate layers stacked in the direction from the inner surface of the upper cover to the lower cover 5, and can have, for example, a form in which one metal plate layer is stacked in the direction from the inner surface of the upper cover to the lower cover, as shown in the schematic cross-sectional diagrams of Figures 1(b) to 1(d) described below.

[0059] The heat insulating reinforcing material according to the present invention is preferably one in which one to three metal plate layers are laminated in the direction from the inner surface of the upper cover toward the lower cover. In the insulating reinforcing material according to the present invention, when a plurality of metal plate layers are stacked, the metal plate layers may be stacked and spaced apart from each other, for example via an inorganic fiber-containing layer.

[0060] In the heat insulating reinforcing material according to the present invention, the total thickness of the metal plate layers constituting the heat insulating reinforcing material is preferably 0.2 to 1.0 mm, more preferably 0.2 to 0.7 mm, and even more preferably 0.2 to 0.5 mm.

[0061] In addition, in this application document, the total thickness of the metal plate layers means the value obtained by determining the thickness of each metal plate layer constituting the insulation reinforcement material of the present invention by the above-mentioned method and adding up the thicknesses of each metal plate layer obtained.

[0062] In the insulating reinforcement material of the present invention, by having the number of layers of metal plate layers and the total thickness within the above-mentioned range, the overall thickness of the insulating reinforcement material of the present invention can be reduced, while the desired reinforcement properties (the effect of suppressing the ejection and scattering of high-temperature molten particles to the outside of the battery pack) can be easily imparted to the battery pack in which the insulating reinforcement material of the present invention is placed.

[0063] The insulating reinforcing material according to the present invention is a laminate of one or more inorganic fiber-containing layers and one or more metal plate layers, and the order and number of the inorganic fiber-containing layers and metal plate layers can be appropriately determined.

[0064] In the insulating reinforcement material of the present invention, the inorganic fiber-containing layer, the metal plate layer, and other constituent layers employed as necessary may be fixed to each other by being joined with an adhesive layer, or may be fixed to each other by being sewn together. In addition, in the insulating reinforcement material of the present invention, the inorganic fiber-containing layer, the metal plate layer, and other constituent layers adopted as necessary may be fixed (integrated) to each other by laminating the entire layer with a protective resin film in a stacked state. Examples of the resin film constituting the protective resin film include the same as those described above, such as one or more selected from PET (polyethylene terephthalate) film, PEN (polyethylene naphthalate) film, PBT (polybutylene terephthalate) film, nylon film, PEEK (polyether ether ketone) film, PPS (polyphenylene sulfide) film, etc. In terms of cost, the protective resin film is preferably a PET film.

[0065] The pressure-sensitive adhesive layer is not particularly limited as long as it is capable of bonding the respective constituent materials, and may be composed of a commercially available double-sided tape or the like. However, it is preferable that the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is a heat-resistant adhesive, and examples of heat-resistant adhesives include silicone adhesives. In the insulating reinforcement material of the present invention, the inorganic fiber-containing layer, the metal plate layer, and other constituent layers employed as necessary are bonded with an adhesive layer made of a heat-resistant adhesive, making it possible to easily suppress peeling between the constituent layers even under high temperature conditions.

[0066] The fibers used for the sewing may be one or more fibers selected from glass fibers, alumina fibers, silica fibers, and the like. In the insulating reinforcement material of the present invention, by sewing together the inorganic fiber-containing layer, the metal plate layer, and other constituent layers adopted as necessary, peeling between the constituent layers can be easily suppressed, even under high temperature conditions, for example.

[0067] 1(b) to 1(d) are enlarged cross-sectional views showing examples of a heat insulating reinforcing material according to the present invention that constitutes a battery pack.

[0068] That is, an example of the insulating reinforcement material of the present invention is an insulating reinforcement material 4A consisting of a laminate in which, when installed, an adhesive layer 4g1, an inorganic fiber-containing layer 4R, an adhesive layer 4g2 and a metal plate layer 4M are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view of Figure 1(b).

[0069] Furthermore, an example of the insulating reinforcing material according to the present invention is an insulating reinforcing material 4B consisting of a laminate in which, when installed, an adhesive layer 4g1, a metal plate layer 4M, an adhesive layer 4g2 and an inorganic fiber-containing layer 4R are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view of Figure 1(c).

[0070] Furthermore, an example of the insulating reinforcement material of the present invention is an insulating reinforcement material 4C consisting of a laminate in which, when installed, an adhesive layer 4g1, an inorganic fiber-containing layer 4R1, an adhesive layer 4g2, a metal plate layer 4M, an adhesive layer 4g3 and an inorganic fiber-containing layer 4R2 are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view of Figure 1(d).

[0071] The insulating reinforcement materials 4A to 4C illustrated in Figures 1(b) to 1(d) have each layer arranged across the entire width of the insulating reinforcement material (each layer is arranged across the entire width of the insulating reinforcement material 4 in the example shown in Figure 1(a)), but for example, the metal plate layer may be provided only in a portion of the entire width of the insulating reinforcement material.

[0072] FIG. 2(a) is a view corresponding to FIG. 1(a) and shows a schematic overall cross-sectional view of an example of a battery pack to which the heat insulating reinforcing material according to the present invention is applied. A battery pack 1 to which the heat insulating reinforcing material according to the present invention is applied, as exemplified in FIG. 2( a ), accommodates one or more power storage modules 2 in a case defined by an upper cover 3 and a lower cover 5 .

[0073] The battery pack 1 illustrated in FIG. 2(a) differs from the battery pack 1 illustrated in FIG. 1(a) in that the shape of the insulating reinforcement material 4 is different, and that the storage modules 2 contained within the battery pack each do not have a gas exhaust port on the surface facing the upper cover 3.

[0074] FIG. 2(b) shows an enlarged cross-sectional view of an example of a form that the heat insulating reinforcing material shown in FIG. 2(a) can take.

[0075] That is, Figure 2(b) shows an insulating reinforcement material 4D according to the present invention, which is a laminate in which, when installed, an adhesive layer 4g, a metal plate layer 4M and an inorganic fiber-containing layer 4R are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view. In the heat insulating reinforcement material 4D shown in FIG. 2(b), the metal plate layers 4M are provided in a portion of the width direction of the heat insulating reinforcement material 4D, that is, a plurality of narrow metal plate layers 4M are provided so as to be scattered in the width direction of the heat insulating reinforcement material 4D.

[0076] FIG. 2(c) shows an enlarged cross-sectional view of another example of a form that the heat insulating reinforcing material shown in FIG. 2(a) can take.

[0077] That is, Figure 2(c) shows an insulating reinforcement material 4E according to the present invention, which is a laminate in which, when installed, an adhesive layer 4g, an inorganic fiber-containing layer 4R1, a metal plate layer 4M and an inorganic fiber-containing layer 4R2 are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view. In the embodiment shown in FIG. 2(c), the inorganic fiber-containing layer 4R1, the metal plate layer 4M and the inorganic fiber-containing layer 4R2 are sewn together at the locations indicated by reference numeral 4s to form an integrated body. In addition, the integrated product shown in Figure 2 (c) may be in a form in which the inorganic fiber-containing layer 4R1, the metal plate layer 4M, and the inorganic fiber-containing layer 4R2 are integrated with each other (not shown) by laminating the entire product with a protective resin film in a stacked state.

[0078] In the insulating reinforcement material 4D shown in Figure 2(b) and the insulating reinforcement material 4E shown in Figure 2(c), the metal plate layers 4M are provided in multiple narrow pieces scattered over a portion of the width direction of the insulating reinforcement material, i.e., in the width direction of the insulating reinforcement material 4D or the insulating reinforcement material 4E. In the insulating reinforcement material 4D shown in FIG. 2(b) and the insulating reinforcement material 4E shown in FIG. 2(c), the metal plate layer 4M is provided so as to be located vertically above the gap provided between the storage modules 2, 2.

[0079] If the above-mentioned smoke or fire occurs from the energy storage module 2 shown in Figure 2(a), or if high-temperature molten particles are ejected or scattered, most of the high-temperature gas, flare (flame) or high-temperature molten particles will eject vertically upward from the ventilation path provided in the battery pack 1, for example, from the gap between the energy storage modules 2, 2. 2(b) and 2(c), by employing a thermal insulation reinforcement 4 in which the metal plate layer 4M is located only vertically above the gap provided between the power storage modules 2, 2, the thermal insulation reinforcement according to the present invention can be partially thinned while easily imparting the desired reinforcement properties (effect of suppressing the spread of fire to the outside of the battery pack and effect of suppressing the ejection and scattering of high-temperature molten particles) to the battery pack in which the thermal insulation reinforcement according to the present invention is disposed. In addition, since the metal plate layer 4M is provided only vertically above the gap provided between the power storage modules 2, 2, the thermal insulation reinforcements 4D and 4E can easily maintain their flexibility and can be easily disposed so as to follow the inner shape of the cover.

[0080] FIG. 3(a) is a diagram corresponding to FIG. 2(a) and shows a schematic overall cross-sectional view of one embodiment of a battery pack to which the heat insulating reinforcing material according to the present invention is applied. A battery pack 1 to which the heat insulating reinforcing material according to the present invention is applied, as exemplified in FIG. 3( a ), accommodates one or more power storage modules 2 in a case defined by an upper cover 3 and a lower cover 5 .

[0081] The battery pack 1 illustrated in FIG. 3(a) differs from the battery pack 1 illustrated in FIG. 2(a) in that the storage modules 2 contained in the battery pack each have a gas exhaust port 21 on the surface facing the upper cover 3 (similar to the battery pack 1 illustrated in FIG. 1(a)).

[0082] Furthermore, the battery pack 1 illustrated in FIG. 3(a) is different from the battery pack 1 illustrated in FIG. 2(a) in the arrangement of the heat insulating reinforcing material 4.

[0083] FIG. 3(b) shows an enlarged cross-sectional view of an example of a form that the heat insulating reinforcing material 4 shown in FIG. 3(a) can take.

[0084] The heat insulating reinforcing material 4F illustrated in FIG. 3(b) has a similar form to the heat insulating reinforcing material 4D illustrated in FIG. 2(b). That is, the insulating reinforcement material 4F illustrated in Figure 3(b) is, as shown in the enlarged cross-sectional view, composed of a laminate in which, when installed, an adhesive layer 4g, a metal plate layer 4M and an inorganic fiber-containing layer 4R are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5. In the insulation reinforcement material 4F shown in FIG. 3(b), the metal plate layers 4M are provided in a portion of the width direction of the insulation reinforcement material 4D, that is, a plurality of narrow metal plate layers 4M are provided so as to be scattered in the width direction of the insulation reinforcement material 4F.

[0085] FIG. 3(c) shows an enlarged cross-sectional view of another example of a form that the heat insulating reinforcing material shown in FIG. 3(a) can take.

[0086] The heat insulating reinforcing material 4G illustrated in FIG. 3(c) has a similar form to the heat insulating reinforcing material 4E illustrated in FIG. 2(c). That is, the insulating reinforcement material 4G illustrated in Figure 3(c) is, as shown in the enlarged cross-sectional view, composed of a laminate in which, when installed, an adhesive layer 4g, an inorganic fiber-containing layer 4R1, a metal plate layer 4M and an inorganic fiber-containing layer 4R2 are laminated in that order from the inner surface of the upper cover 3 toward the lower cover 5. In the embodiment shown in FIG. 3(c), the inorganic fiber-containing layer 4R1, the metal plate layer 4M and the inorganic fiber-containing layer 4R2 are sewn together at the locations indicated by reference numeral 4s to form an integrated body. In addition, the integrated product shown in Figure 3 (c) may be in a form in which the inorganic fiber-containing layer 4R1, the metal plate layer 4M, and the inorganic fiber-containing layer 4R2 are integrated with each other (not shown) by laminating the entire product with a protective resin film in a stacked state.

[0087] In the insulating reinforcement material 4F shown in Figure 3(b) and the insulating reinforcement material 4G shown in Figure 3(c), multiple narrow metal plate layers 4M are provided in a portion of the width direction of the insulating reinforcement material, i.e., scattered in the width direction of the insulating reinforcement material 4F or the insulating reinforcement material 4G. In the insulating reinforcement material 4F shown in FIG. 3(b) and the insulating reinforcement material 4G shown in FIG. 3(c), the metal plate layer 4M is provided so as to be located vertically above the gas exhaust port 21 provided in the storage module 2.

[0088] When the above-mentioned smoke or fire occurs from the energy storage module 2 shown in Figure 3 (a), or when high-temperature molten particles are ejected or scattered, most of the high-temperature gas, flare (flame), or high-temperature molten particles will be ejected vertically upward from the gas exhaust port 21 provided in the energy storage module 2. In this case, by adopting a heat insulating reinforcement material in which the metal plate layer 4M is located only vertically above each power storage module 2 (vertically above the gas exhaust port 21 provided in each power storage module), such as the heat insulating reinforcement material 4F shown in Fig. 3(b) or the heat insulating reinforcement material 4G shown in Fig. 3(c), it is possible to easily impart the desired reinforcement properties (effect of suppressing the spread of fire to the outside of the battery pack and effect of suppressing the ejection and scattering of high-temperature molten particles) to the battery pack in which the heat insulating reinforcement material according to the present invention is arranged, while partially thinning the heat insulating reinforcement material according to the present invention. In addition, since the metal plate layer 4M is provided only vertically above each power storage module 2, the heat insulating reinforcement materials 4F and 4G can easily maintain their flexibility and can be easily arranged so as to follow the inner shape of the cover.

[0089] Furthermore, the heat insulating reinforcing material according to the present invention may have, for example, one or more insulating material layers in addition to one or more inorganic fiber-containing layers and one or more metal plate layers. The insulating material layer may be, for example, a plate-like plate (mica plate) made of mica.

[0090] When the heat insulating reinforcing material according to the present invention has an insulating layer, the insulating layer is suitably provided as the outermost layer on the side facing the electricity storage module during installation.

[0091] FIG. 4(a) is a view corresponding to FIG. 1(a) and shows a schematic cross-sectional view of an example of a battery pack to which the heat insulating reinforcing material according to the present invention is applied. A battery pack 1 to which the heat insulating reinforcing material according to the present invention is applied, as exemplified in FIG. 4(a), accommodates one or more power storage modules 2 in a case defined by an upper cover 3 and a lower cover 5.

[0092] The battery pack 1 illustrated in FIG. 4(a) is different from the battery pack 1 illustrated in FIG. 1(a) in the form of the heat insulating reinforcing material 4.

[0093] Figures 4(b) to 4(d) show enlarged cross-sectional views of possible forms of the insulating reinforcing material illustrated in Figure 4(a), each of which is an example of the insulating reinforcing material illustrated in Figures 1(b) to 1(d) to which an insulating layer is further provided.

[0094] That is, an example of the insulating reinforcement material of the present invention is an insulating reinforcement material 4H consisting of a laminate in which, when installed, an adhesive layer 4g1, an inorganic fiber-containing layer 4R, an adhesive layer 4g2, a metal plate layer 4M, an adhesive layer 4g3 and an insulator layer 4i are stacked in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view of Figure 4(b).

[0095] Furthermore, an example of the insulating reinforcement material according to the present invention is an insulating reinforcement material 4I consisting of a laminate in which, when installed, an adhesive layer 4g1, a metal plate layer 4M, an adhesive layer 4g2, an inorganic fiber-containing layer 4R, an adhesive layer 4g3 and an insulator layer 4i are laminated in that order in the direction from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view of Figure 4(c).

[0096] Furthermore, an example of the insulating reinforcement material according to the present invention is an insulating reinforcement material 4J consisting of a laminate in which, when arranged, an adhesive layer 4g1, an inorganic fiber-containing layer 4R1, an adhesive layer 4g2, a metal plate layer 4M, an adhesive layer 4g3, an inorganic fiber-containing layer 4R2, an adhesive layer 4g4 and an insulator layer 4i are stacked in that order from the inner surface of the upper cover 3 toward the lower cover 5, as shown in an enlarged cross-sectional view in Figure 4(d).

[0097] The insulating reinforcement material of the present invention faces a storage module (storage module 2 in the example of Figure 4(a)), and since the insulating reinforcement material of the present invention has an insulating layer in addition to an inorganic fiber-containing layer and a metal plate layer, it can exhibit suitable insulating properties with respect to the opposing storage module.

[0098] Although not shown in Figures 1 to 4, each battery pack 1 shown in Figures 1 to 4 may further include a protection circuit for preventing overcharging, over-discharging, or overheating of the storage module 2, a BMS (battery management system) for monitoring voltage and temperature, or a charge / discharge circuit, a cooling mechanism, etc.

[0099] The thickness of the heat insulating reinforcing material according to the present invention is preferably 0.3 to 5.0 mm, more preferably 0.3 to 3.5 mm, even more preferably 0.3 to 2.5 mm, and even more preferably 0.5 to 1.5 mm.

[0100] Since the insulating reinforcement material of the present invention is within the above range, even when the width between the upper cover of the battery pack and the storage module is narrow, it can be easily arranged inside the upper cover while exhibiting excellent insulating properties, and even if an abnormality occurs in the secondary battery cell that constitutes the storage module, damage to various components can be effectively suppressed.

[0101] In the present application, the thickness of the heat insulating reinforcing material means the arithmetic average value when the thickness is measured at any five points of the heat insulating reinforcing material using a micrometer.

[0102] According to the present invention, it is possible to provide an insulating reinforcement material for a battery pack cover that exhibits suitable insulating properties and can effectively suppress damage to various components even if an abnormality occurs in a secondary battery cell that constitutes a storage module.

[0103] Next, the battery pack according to the present invention will be described. The battery pack according to the present invention is a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, A cover insulating reinforcement material having one or more inorganic fiber-containing layers and one or more metal plate layers laminated thereon is provided on the inside of the cover of the battery pack. It is characterized by the above.

[0104] The battery pack according to the present invention has the heat insulating reinforcing material according to the present invention provided on the inside of the cover of the battery pack. The contents of the battery pack according to the present invention are as described in the explanation of the heat insulating reinforcing material for a battery pack cover according to the present invention, and the details are as described above.

[0105] According to the present invention, it is possible to provide a battery pack that exhibits suitable thermal insulation properties and can effectively suppress damage to various components even if an abnormality occurs in a secondary battery cell that constitutes a storage module.

[0106] The present invention will now be described in more detail with reference to the following Reference Examples, which are merely illustrative and do not limit the present invention.

[0107] (Reference Examples 1 to 2 and Comparative Reference Example 1) As test pieces to be used in Reference Examples 1 and 2 and Comparative Reference Example 1, the following test pieces were prepared. Reference example 1: Stainless steel plate (SUS301) 100 mm long, 100 mm wide, 0.4 mm thick Reference example 2: Cold-rolled steel plate (SPCC) with a length of 100 mm, width of 100 mm, and thickness of 0.4 mm Comparative example 1: Mica plate 100mm long, 100mm wide, 1.1mm thick

[0108] <Blast resistance evaluation> For each of the test pieces, a blast resistance evaluation test (durability test against ejection and scattering of particles) was carried out under the following conditions. Blast resistance evaluation test equipment: Blast cabinet BS-2 type (manufactured by Atsuji Tekko Co., Ltd.) Test method: The ejection port of the blast resistance evaluation test device described above was placed at a position 230 mm vertically above the test piece, and soda-lime glass (specific gravity 2.5 g / cm3) was used as abrasive grains. 3 , particle size 300-425μm) and alumina abrasive (specific gravity 3.9g / cm 3 A 1:1 volumetric mixture of abrasive grains (particle size 325-400 μm) was used, and the abrasive grains were ejected from a 10 mm diameter nozzle at a pressure of 0.3 MPa for 40 seconds onto the test piece, after which the appearance was visually inspected to confirm whether or not there was penetration.

[0109] The results of the blast resistance evaluation test are shown in Table 1. The results of the test were evaluated as follows: no penetration was indicated by "◯" and penetration was indicated by "×".

[0110] [Table 1]

[0111] From the results of Reference Examples 1 and 2 above, it can be seen that by using one or more metal plate layers stacked as a cover insulating reinforcement material to be placed inside the cover of a battery pack in which one or more energy storage modules having multiple secondary battery cells are housed in a case, even if molten particles are ejected or scattered from the energy storage module, the use of a material having one or more metal plate layers stacked as a cover insulating reinforcement material has an excellent effect of suppressing damage to the battery pack and components placed outside the battery pack.

[0112] On the other hand, the results of Comparative Reference Example 1 above show that when one or more mica plates are stacked as a cover insulating reinforcement material to be placed inside the cover of a battery pack in which one or more energy storage modules having multiple secondary battery cells are housed in a case, the effect of suppressing damage to the battery pack and components placed outside the battery pack is inferior when molten particles are erupted and scattered from the energy storage module. [Industrial Applicability]

[0113] According to the present invention, it is possible to provide an insulating reinforcement material for a battery pack cover and a battery pack that exhibit suitable insulating properties and can effectively suppress damage to various components even if an abnormality occurs in a secondary battery cell that constitutes a storage module. [Explanation of symbols]

[0114] 1, 11 Battery pack 2, 12 Energy storage module 3, 13 Upper cover 4, 4A~4J, 14 Thermal insulation reinforcement material 4R, 4R1, 4R2 Inorganic fiber-containing layer 4M metal plate layer 4i Insulator layer 5, 15 Lower cover

Claims

1. A heat insulating reinforcement member for a cover is disposed on an inner side of a cover of a battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, the reinforcement member comprising: One or more inorganic fiber-containing layers and one or more metal plate layers are laminated. A heat insulating reinforcement material for a battery pack cover.

2. A battery pack in which one or more storage modules having a plurality of secondary battery cells are housed in a case, A cover insulating reinforcement material having one or more inorganic fiber-containing layers and one or more metal plate layers laminated thereon is provided on the inside of the cover of the battery pack. A battery pack characterized by:

Images