Battery box, battery, preparation method of battery and power utilization device

Abstract

The invention provides a battery box, a battery, a preparation method of the battery and a power utilization device. The battery box comprises a resin matrix and a reinforced fiber layer arranged in the resin matrix, the resin matrix comprises thermosetting resin, a functional filler and a silane coupling agent, and the functional filler is dispersed in the thermosetting resin; in the composition materials, the mass ratio of the thermosetting resin to the reinforced fiber layer to the functional filler to the silane coupling agent is 100: (20-60): (1-20): (0.1-2). The battery box disclosed by the invention is prepared from specific components, is light in weight and has good tensile strength, impact resistance and corrosion resistance, so that the sealing property and the impact resistance of the battery can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery box, a battery, a method for preparing the same, and an electrical device thereof. Background Technology

[0002] In recent years, batteries have been used in a wide range of applications, including energy storage power systems such as hydropower, thermal power, wind power and solar power plants, as well as in power tools, electric bicycles, electric motorcycles, electric cars, military equipment, aerospace and many other fields.

[0003] Batteries are subject to impacts, compression, and even severe deformation under operating conditions, leading to dangers such as battery rupture, electrolyte leakage, battery fire, and explosion. Taking power batteries as an example, power batteries provide power to vehicles such as electric cars, electric trains, electric bicycles, and golf carts. For instance, when power batteries are used in electric vehicles, these vehicles frequently encounter bottoming out and bumping into things on roads with varying conditions, causing the power batteries to be impacted, compressed, or even severely deformed, leading to dangers such as battery rupture, electrolyte leakage, battery fire, and explosion. As the carrier and protection unit of the battery, the structure and performance of the battery box are crucial to battery safety.

[0004] Currently, battery casings are primarily made of sheet metal. This material results in heavy casings, poor corrosion resistance, and a tendency to rust and damage, leading to weakened battery sealing and reduced impact resistance. Furthermore, the high rigidity of this material makes it poor at absorbing impact energy during collisions, further contributing to the battery's poor impact resistance. Therefore, traditional technologies need improvement. Summary of the Invention

[0005] To achieve the above objectives, this application provides a battery box, a battery, a method for preparing the same, and an electrical device thereof. The battery box is lightweight and has good tensile strength, impact resistance, and corrosion resistance. When applied to a battery, it can improve the battery's sealing and impact resistance.

[0006] In a first aspect, this application provides a battery box, the constituent materials of which include a resin matrix and a reinforcing fiber layer disposed in the resin matrix, the resin matrix comprising a thermosetting resin, a functional filler and a silane coupling agent, the functional filler being dispersed in the thermosetting resin; wherein the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler and the silane coupling agent in the constituent materials is 100:(20~60):(1~20):(0.1~2).

[0007] The battery box described in this application comprises a resin matrix and a reinforcing fiber layer disposed within the resin matrix. The resin matrix has a specific proportion of components, and the mass ratio of each component to the reinforcing fiber layer is defined. The reinforcing fiber layer, as a layered structure, enhances the strength of the resin matrix at the layered level. Functional fillers dispersed in the thermosetting resin enhance the strength of the resin matrix at the material level. Thus, the reinforcing fiber layer and functional fillers synergistically enhance the strength of the thermosetting resin. A silane coupling agent improves the interfacial bonding between the functional fillers, reinforcing fiber layer, and thermosetting resin. The synergistic effect of these components improves the tensile strength and impact resistance of the resin matrix containing the reinforcing fiber layer. Furthermore, because the resin matrix is ​​thermosetting, it combines lightweight and good corrosion resistance compared to sheet metal materials. Therefore, the aforementioned battery box is lightweight and possesses good tensile strength, impact resistance, and corrosion resistance, thereby improving the battery's sealing and impact resistance.

[0008] In some embodiments, the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler, and the silane coupling agent in the battery box components is 100:(30~40):(5~15):(0.5~1.5). Controlling the composition of the battery box within the above-mentioned ratio range allows the battery box to possess both better tensile strength and impact resistance.

[0009] In some implementations, one or more of the following conditions are met:

[0010] (1) The fibers in the reinforcing fiber layer include one or more of plant fibers, aramid fibers, basalt fibers, polyester fibers, polyethylene fibers, polypropylene fibers, nylon fibers, glass fibers and carbon fibers;

[0011] (2) The reinforcing fiber layer includes one or more of fiber felt and fiber cloth;

[0012] (3) The thickness of a single reinforcing fiber layer is 0.10 mm to 0.50 mm;

[0013] (4) The wall thickness of the battery box is 1.5mm~3mm.

[0014] The battery box is thin and lightweight, while also possessing good tensile strength, impact resistance, and corrosion resistance, which can improve the battery's sealing and impact resistance.

[0015] In some embodiments, the thermosetting resin includes one or more of epoxy resin, benzoxazine resin, phenolic resin, thermosetting polyimide resin, bismaleimide resin, polyester resin, vinyl ester resin, cyanate ester resin, and derivatives thereof.

[0016] In some embodiments, the functional filler includes one or more of hollow glass microspheres, calcium carbonate, aluminum hydroxide, alumina, and mica.

[0017] In some embodiments, the Dv50 particle size of the hollow glass microspheres is 10 micrometers to 110 micrometers. Controlling the Dv50 particle size of the hollow glass microspheres within this range balances the dispersibility of the functional filler in the resin matrix with its reinforcing strength effect. Furthermore, the hollow glass microspheres have the advantage of a low dielectric constant, thus reducing the dielectric constant of the resulting battery pack.

[0018] In some embodiments, the silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, 3-glycidylpropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, 3-aminopropyltrimethoxysilane, and isobutyltriethoxysilane.

[0019] In some embodiments, the battery box includes an upper box and a lower box, the upper box being able to cover the lower box and cooperate with the lower box to form a receiving cavity, and at least one of the upper box and the lower box being composed of the resin matrix and the reinforcing fiber layer disposed in the resin matrix.

[0020] In some embodiments, both the upper box and the lower box include a bottom plate and a side plate connected to the bottom plate. The bottom plate and the side plate are both made of the resin matrix and the reinforcing fiber layer, and the reinforcing fiber layer in the bottom plate and the side plate is an integral structure.

[0021] In a second aspect, this application provides a battery comprising a battery cell and the battery case provided in the first aspect of this application, wherein the battery cell is disposed within the battery case.

[0022] A third aspect of this application provides a method for manufacturing a battery box, comprising the following steps:

[0023] The reinforcing fiber layer is placed inside the cavity of the mold;

[0024] The raw material of the resin matrix is ​​injected into the cavity of the mold and cured to form the resin matrix, and then demolded; wherein, the components of the resin matrix include thermosetting resin, functional filler and silane coupling agent, the functional filler is dispersed in the thermosetting resin, and the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler and the silane coupling agent is 100: (20~60): (1~20): (0.1~2).

[0025] The aforementioned method for manufacturing battery boxes uses injection molding, which is simple to process and has a short processing cycle. In contrast, manufacturing battery boxes using sheet metal materials involves complex machining, a long processing cycle, and high time costs.

[0026] The aforementioned battery box possesses excellent tensile strength, impact resistance, and corrosion resistance. Furthermore, due to its thermosetting resin matrix, it combines lightweight construction with superior corrosion resistance compared to sheet metal materials. Thus, the lightweight battery box, along with its excellent tensile strength, impact resistance, and corrosion resistance, enhances the battery's sealing and impact resistance.

[0027] In some implementations, one or more of the following conditions are met:

[0028] (1) The injection step employs resin transfer molding technology;

[0029] (2) In the injection step, the preheating temperature of the resin matrix raw material and the mold is 40℃~60℃;

[0030] (3) The injection pressure is 2MPa~3MPa and the injection rate is 50mL / min~100mL / min;

[0031] (4) The curing process includes sequentially treating at 120℃~140℃ for 3h~5h, at 150℃~170℃ for 1h~3h, and at 180℃~220℃ for 3h~5h;

[0032] (5) The dynamic viscosity of the mixture of raw materials of the resin matrix at 40℃~60℃ is 300mPa·s~2500mPa·s.

[0033] RTM (Resin Transfer Molding) technology is a low-cost method for manufacturing composite materials, which has the advantages of high efficiency, low cost, good part quality, high dimensional accuracy, and minimal environmental impact.

[0034] Preheating the resin matrix raw materials and the mold at the above-mentioned preheating temperature helps to improve the mixing uniformity of the resin matrix raw materials, thereby improving the uniformity of the components in the resin matrix.

[0035] Curing by sequentially increasing the temperature can promote curing uniformity, resulting in a resin matrix with good curing uniformity, which is beneficial to improving the material properties uniformity of the battery box.

[0036] In a fourth aspect, this application provides an electrical device comprising at least one of the battery box described in the first aspect of this application, the battery described in the second aspect of this application, and the battery box prepared by the preparation method described in the third aspect of this application.

[0037] The electrical device of this application includes the battery box provided in this application, and therefore has at least the same advantages as the battery box.

[0038] Details of one or more embodiments of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0039] To better describe and illustrate the embodiments or examples provided in this application, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed applications, the currently described embodiments or examples, or the best mode of conduct of these applications as currently understood. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0040] Figure 1 This is a schematic diagram of a battery according to one embodiment of this application.

[0041] Figure 2 yes Figure 1 An exploded view of a battery according to one embodiment of this application is shown.

[0042] Figure 3 This is a schematic diagram of a battery module in a battery according to one embodiment of this application.

[0043] Figure 4 This is a schematic diagram of a single battery cell in a battery according to one embodiment of this application.

[0044] Figure 5 yes Figure 4 An exploded view of a battery cell according to one embodiment of this application is shown.

[0045] Figure 6 This is a schematic diagram of an electrical device in which a battery is used as a power source according to one embodiment of this application.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. Battery; 2. Upper casing; 3. Lower casing; 4. Battery module; 5. Battery cell; 51. Housing; 52. Electrode assembly; 53. Cover plate. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] The "range" disclosed in this application can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints; any endpoint can be independently included or excluded, and they can be combined arbitrarily, meaning any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this document; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, stating that a parameter is an integer ≥2 is equivalent to disclosing that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, stating that a parameter is an integer selected from "2-10" is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0050] In this application, the terms "multiple" or "various" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "one or more" means one or more types.

[0051] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. The term "implementation" as used herein has a similar understanding.

[0053] Those skilled in the art will understand that the order in which the steps are written in the methods of various embodiments or examples does not imply a strict execution order and does not constitute any limitation on the implementation process. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0054] In this application, open-ended technical features or solutions described using terms such as "containing," "including," or "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, if A includes a1, a2, and a3, it may also include other members or exclude additional members unless otherwise specified. This can be considered as providing both the feature or solution that "A consists of a1, a2, and a3" and the feature or solution that "A includes not only a1, a2, and a3, but also other members."

[0055] In this application, unless otherwise specified, A (e.g., B) means that B is a non-limiting example of A, and it is understood that A is not limited to B.

[0056] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0057] To improve battery sealing and impact resistance, some technologies involve installing protective structures on the battery at the bottom of the vehicle to prevent deformation from impacts. Some of these protective structures use steel plates, but steel plates offer virtually no cushioning and, combined with vehicle bumps, can actually damage the battery. Furthermore, steel plates that are too thin have low strength, while those that are too thick are too heavy, unsuitable for the strength and lightweight requirements of electric vehicles. Some systems use multi-layered protective plates, but due to insufficient bonding between the layers, these plates can easily delaminate after impacts or scratches, thus losing their protective function.

[0058] Based on this, one embodiment of this application provides a battery and its battery case. The battery includes a battery case. The battery case is composed of a resin matrix and a reinforcing fiber layer disposed within the resin matrix. The resin matrix comprises a thermosetting resin, a functional filler, and a silane coupling agent. The functional filler is dispersed in the thermosetting resin. In the composition of the battery case, the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler, and the silane coupling agent is 100:(20~60):(1~20):(0.1~2).

[0059] Based on the quality of the thermosetting resin, excessive addition of the reinforcing fiber layer will reduce the impact resistance of the battery box, while insufficient addition will make it difficult to improve the tensile strength of the battery box. Similarly, based on the quality of the thermosetting resin, excessive addition of the functional filler will reduce the impact resistance of the battery box, while insufficient addition will make it difficult to improve the tensile strength of the battery box. Furthermore, based on the quality of the thermosetting resin, excessive addition of the silane coupling agent will interfere with the curing process of the thermosetting resin, thus reducing the strength of the battery box. In addition, insufficient addition of the silane coupling agent will not significantly improve the interfacial bonding between the functional filler and the reinforcing fiber layer and the thermosetting resin.

[0060] The battery described in this application comprises a resin matrix and a reinforcing fiber layer within the resin matrix. The resin matrix has a specific proportion of components, and the mass ratio of each component to the reinforcing fiber layer is defined. The reinforcing fiber layer, as a layered structure, enhances the strength of the resin matrix at the layered level. Functional fillers dispersed in the thermosetting resin enhance the strength of the resin matrix at the material level. Thus, the reinforcing fiber layer and functional fillers synergistically enhance the strength of the thermosetting resin. A silane coupling agent improves the interfacial bonding between the functional fillers, the reinforcing fiber layer, and the thermosetting resin. The synergistic effect of these components improves the tensile strength and impact resistance of the resin matrix containing the reinforcing fiber layer. Furthermore, because the resin matrix is ​​a curable resin matrix, it combines lightweight and good corrosion resistance compared to sheet metal materials. Therefore, the aforementioned battery box is lightweight and possesses good tensile strength, impact resistance, and corrosion resistance, thereby improving the battery's sealing and impact resistance.

[0061] In some embodiments, the thermosetting resin includes one or more of epoxy resin, benzoxazine resin, phenolic resin, thermosetting polyimide resin, bismaleimide resin, polyester resin, vinyl ester resin, cyanate ester resin, and derivatives thereof. Optionally, the thermosetting resin includes one or more of epoxy resin, benzoxazine resin, phenolic resin, and derivatives thereof, which have superior strength and lower cost.

[0062] Understandably, during the manufacturing process of the battery box, thermosetting resin can be formed through a curing reaction of the corresponding resin. Understandably, the thermosetting resin in the above-mentioned battery box refers to the cured thermosetting resin.

[0063] Among them, single-component curable resins such as benzoxazine resin, thermosetting polyimide resin and bismaleimide resin do not require the addition of curing agent during the curing process and can be cured under curing conditions such as heating or light.

[0064] The curing process of polyester resin mainly involves free radical reaction. Initiators such as peroxide initiators can be added to promote the curing reaction. Initiators include, but are not limited to, one or more of cyclohexanone peroxide or methyl ethyl ketone peroxide. If necessary, the curing reaction can also be promoted under curing conditions such as heating or light.

[0065] The curing of cyanate ester resins generally involves adding catalysts such as organotin compounds to promote the curing reaction, which can then be cured under curing conditions such as heating or light.

[0066] For two-component curable resins such as epoxy resins, phenolic resins, and vinyl ester resins, a curing agent must be added during the curing process. If necessary, the curing reaction can be accelerated under curing conditions such as heating or light. Curing agents for epoxy resins include, but are not limited to, one or more of ethylenediamine, diethylenetriamine, m-phenylenediamine, polyamide, maleic anhydride, and phthalic anhydride; the general dosage is 10% to 50% of the corresponding resin mass. Curing agents for phenolic resins include, but are not limited to, one or more of hexamethylenetetramine, triethanolamine, ammonium chloride, and p-toluenesulfonic acid; the general dosage is 2% to 20% of the corresponding resin mass. Curing agents for vinyl ester resins include, but are not limited to, one or more of benzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, and methyl ethyl ketone peroxide; the general dosage is 1% to 10% of the corresponding resin mass.

[0067] In some embodiments, the fibers in the reinforcing fiber layer include one or more of plant fibers, aramid fibers, basalt fibers, polyester fibers, polyethylene fibers, polypropylene fibers, nylon fibers, glass fibers, and carbon fibers. Optionally, the fibers in the reinforcing fiber layer include one or more of glass fibers and carbon fibers. Optionally, the fibers in the reinforcing fiber layer include carbon fibers, which have the advantages of low density and high strength. As an example, the reinforcing fiber layer is a carbon fiber layer, including but not limited to carbon fiber plain weave fabric.

[0068] In some embodiments, the reinforcing fiber layer includes one or more of fiber felt and fiber cloth. Fiber felt and fiber cloth are two common fiber material products. Structurally, fiber cloth typically has a tighter weave, consisting of multiple fine fibers interwoven to form a mesh structure; while fiber felt has a relatively loose structure, with fibers arranged irregularly, giving it a certain degree of flexibility. In terms of performance, fiber cloth generally has higher tensile strength, heat resistance, and corrosion resistance; while fiber felt has better flexibility and thermal insulation.

[0069] As an example, in the battery box, if the mass fraction of thermosetting resin is 100 parts, the mass fraction of the reinforcing fiber layer can be 20, 25, 30, 35, 40, 45, 50, 55, or 60, or within the range formed by any two of the above points as endpoints. For example, the mass fraction of the reinforcing fiber layer can be 30 to 40 parts.

[0070] In some embodiments, the thickness of a single reinforcing fiber layer is 0.10 mm to 0.50 mm. For example, it can be 0.10 mm, 0.20 mm, 0.30 mm, 0.40 mm, 0.50 mm, or any two of the above values ​​as endpoints. One or more reinforcing fiber layers can be provided as needed.

[0071] In some embodiments, the functional fillers include inorganic fillers, including but not limited to one or more of hollow glass microspheres, calcium carbonate, aluminum hydroxide, alumina, and mica. The addition of these functional fillers can improve the strength and rigidity of the resin matrix.

[0072] Furthermore, the functional fillers include, but are not limited to, hollow glass microspheres. Furthermore, the actual density of the hollow glass microspheres is 0.10 g / cm³. 3 ~0.72g / cm 3 Insulating glass microspheres have advantages such as light weight, low thermal conductivity, and good stability. In addition, they also have the functions of insulation, self-lubrication, sound insulation, heat insulation, water resistance, corrosion resistance, and radiation protection. When filled into a resin matrix, they can improve the strength, rigidity, wear resistance, insulation, and corrosion resistance of the resin.

[0073] Furthermore, the Dv50 particle size of the hollow glass microspheres is 10 micrometers to 110 micrometers. Controlling the Dv50 particle size within this range allows for a balance between the dispersibility of the functional filler in the resin matrix and its reinforcing strength effect. In addition, hollow glass microspheres have the advantage of a low dielectric constant, thus reducing the dielectric constant of the resulting battery box. This low dielectric constant is beneficial for reducing communication interference during signal transmission. As an example, the Dv50 particle size of the hollow glass microspheres can be 10 micrometers, 20 micrometers, 30 micrometers, 40 micrometers, 50 micrometers, 60 micrometers, 70 micrometers, 80 micrometers, 90 micrometers, 100 micrometers, or 110 micrometers, or any two of the above values ​​as endpoints. Optionally, the Dv50 particle size of the hollow glass microspheres is 30 micrometers to 50 micrometers.

[0074] Dv50 has a well-known meaning in the art and can be tested using methods known in the art. For example, it can be measured using a laser particle size analyzer (such as the Malvern Master Size 3000). Here, Dv50 represents the particle size at which the percentage of particle volume distribution accumulates to 50% based on the particle size distribution, starting from the smallest particle size.

[0075] Particle size distribution can be obtained by the following method: Take a clean beaker, add an appropriate amount of the sample to be tested, and sonicate thoroughly to ensure complete dispersion. The testing instrument is a Malvern 2000 (USA). After the sample is poured into the injection tower, it circulates with the solution to the test optical path system. Under the illumination of the laser beam, the particle size distribution characteristics can be obtained by receiving and measuring the energy distribution of the scattered light (opause: 8-12%). Particle size distribution diagrams are plotted based on the test data.

[0076] As an example, in the battery box, if the mass fraction of thermosetting resin is 100 parts, the mass fraction of functional filler can be 1, 5, 10, 15, or 20 parts, or within the range formed by any two of the above points as endpoints. For example, the mass fraction of functional filler can be 5 to 15 parts.

[0077] As an example, in the battery box, if the mass fraction of thermosetting resin is 100 parts, the mass fraction of silane coupling agent can be 0.1, 0.5, 1, 1.5, 2, or within the range formed by any two of the above points as endpoints. For example, the mass fraction of silane coupling agent can be 0.5 parts to 1.5 parts.

[0078] In some embodiments, the mass ratio of thermosetting resin, reinforcing fiber layer, functional filler, and silane coupling agent in the battery box components is 100:(30~40):(5~15):(0.5~1.5). Controlling the battery box components within the above-mentioned ratio range allows the battery box to possess both better tensile strength and impact resistance.

[0079] In some embodiments, the thermosetting resin includes benzoxazine resin, the reinforcing fiber layer includes a carbon fiber layer, and the functional filler includes hollow glass microspheres.

[0080] In some embodiments, the battery box wall thickness is 1.5mm to 3mm. For example, the wall thickness can be 1.5mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.6mm, 2.8mm, or 3mm, or any two of the above values ​​as endpoints. This battery box is thin and lightweight, while also possessing good tensile strength, impact resistance, and corrosion resistance, thereby improving the battery's sealing and impact resistance.

[0081] In some embodiments, the battery box includes an upper box and a lower box, the upper box being able to cover the lower box and cooperate with the lower box to form a receiving cavity.

[0082] The aforementioned battery also includes individual battery cells, which are located inside the battery case; specifically, the individual battery cells are located within the receiving cavity of the battery case.

[0083] The constituent materials of at least one of the upper and lower housings include the aforementioned resin matrix and the aforementioned reinforcing fiber layer disposed within the resin matrix.

[0084] As an example, the upper and lower housings are both made of a resin matrix containing the aforementioned reinforcing fiber layer.

[0085] Furthermore, both the upper and lower boxes include a bottom plate and a side plate connected to the bottom plate. This forms a box with an opening at one end, and the openings of the upper and lower boxes fit together to form the aforementioned receiving cavity.

[0086] Furthermore, both the bottom plate and the side plate of the container include a resin matrix and a reinforcing fiber layer, and the reinforcing fiber layer in the bottom plate and the side plate is an integral structure.

[0087] Understandably, the upper or lower housing is composed of a resin matrix with a reinforcing fiber layer, meaning the main structure of the upper or lower housing is formed by the upper or lower housing. The resin matrix forms the aforementioned housing structure with an open end. Furthermore, to uniformly distribute the reinforcing fiber layer therein, the reinforcing fiber layer also surrounds the aforementioned housing structure with an open end, thereby uniformly distributing it on the bottom and side panels of the upper or lower housing.

[0088] In other examples, the reinforcing fiber layer may also be distributed in certain areas of the enclosure structure, such as only in the middle of the bottom plate or side plate, and not at the edges.

[0089] The shapes of the upper and lower boxes are not limited; they can be, but are not limited to, cuboid or cuboid-like structures.

[0090] In some embodiments, one or more battery cells can be assembled into a battery module, and then the one or more battery modules can be placed in the receiving cavity of the battery box; alternatively, one or more battery cells can be directly placed in the receiving cavity of the battery box. The number of battery cells contained in a battery module can be one or more, and those skilled in the art can select an appropriate number based on the application and capacity of the battery module. The number of battery modules within the battery box can also be one or more, and those skilled in the art can select an appropriate number based on the application and capacity of the battery pack.

[0091] Figure 1 and Figure 2 This is battery 1 as an example. (See reference...) Figure 2 The battery 1 includes a battery box and multiple battery modules 4 disposed within the battery box. The battery box includes an upper box 2 and a lower box 3, the upper box 2 covering the lower box 3, and the upper box 2 and the lower box 3 together forming a receiving cavity for accommodating the battery modules 4. The multiple battery modules 4 can be arranged in any manner within the battery box.

[0092] Figure 3 This is battery module 4, used as an example. (See reference...) Figure 3 In battery module 4, multiple battery cells 5 can be arranged sequentially along the length of battery module 4. Of course, they can also be arranged in any other manner. Furthermore, these multiple battery cells 5 can be fixed in place using fasteners.

[0093] Optionally, the battery module 4 may also include a housing with a receiving space in which multiple battery cells 5 are received.

[0094] In another aspect, this application provides a method for preparing a battery box, comprising the following steps S11-S12:

[0095] S11. Place the reinforcing fiber layer inside the cavity of the mold.

[0096] In some embodiments, the reinforcing fiber layer is uniformly laid within the cavity of the mold, according to its shape; understandably, this is also possible in other embodiments. For example, multiple reinforcing fiber layers may be distributed in different areas, or pressure may be applied to press a single reinforcing fiber layer into the shape of the cavity.

[0097] In some embodiments, the battery box includes the lower box and the upper box described above. At least one of the upper box and the lower box is prepared using steps S11-S12 described above. Further, in the preparation of the battery box, both the upper box and the lower box are prepared using steps S11-S12 described above. Further, in order to uniformly distribute the reinforcing fiber layer therein, the reinforcing fiber layer also surrounds the box structure forming the one-end opening described above, thereby uniformly distributing it on the bottom plate and side plate of the upper or lower box. Specifically, the reinforcing fiber layer can be pressed into the cavity of a mold under pressure to form a shape similar to the mold cavity, and excess portions can be trimmed.

[0098] S12. The raw material of the resin matrix is ​​injected into the cavity of the mold and cured to form the resin matrix, and then demolded; wherein, the components of the resin matrix include thermosetting resin, functional filler and silane coupling agent, and the functional filler is dispersed in the thermosetting resin. The mass ratio of thermosetting resin, reinforcing fiber layer, functional filler and silane coupling agent is 100:(20~60):(1~20):(0.1~2).

[0099] The aforementioned method for manufacturing battery boxes uses injection molding, which is simple to process and has a short processing cycle. In contrast, manufacturing battery boxes using sheet metal materials involves complex machining, a long processing cycle, and high time costs.

[0100] The aforementioned battery box possesses excellent tensile strength, impact resistance, and corrosion resistance. Furthermore, due to its thermosetting resin matrix, it combines lightweight construction with superior corrosion resistance compared to sheet metal materials. Thus, the lightweight battery box, along with its excellent tensile strength, impact resistance, and corrosion resistance, enhances the battery's sealing and impact resistance.

[0101] In some embodiments, the injection step in S12 employs resin transfer molding (RTM) technology. RTM technology is a low-cost method for manufacturing composite materials, offering advantages such as high efficiency, low cost, high part quality, high dimensional accuracy, and minimal environmental impact. It can be applied to the molding of large, complex, and high-strength composite material parts.

[0102] Furthermore, the above injection step includes the following steps: first, the raw materials of the resin matrix are mixed and preheated, and then the resulting mixture is injected into a mold with a reinforcing fiber layer. Further, the mold is also preheated during injection. This helps to improve the mixing uniformity of the raw materials of the resin matrix, thereby improving the uniformity of the components in the resin matrix.

[0103] Furthermore, in the injection step, the preheating temperature of the resin matrix raw material and the mold is 40°C to 60°C; as an example, the preheating temperature can be 40°C, 45°C, 50°C, 55°C, 60°C, or any two of the above points as end values.

[0104] Furthermore, the dynamic viscosity of the mixture of raw materials for the resin matrix is ​​controlled to be 300 mPa·s to 2500 mPa·s at 40°C to 60°C. For example, it can be 300 mPa·s, 400 mPa·s, 500 mPa·s, 600 mPa·s, 700 mPa·s, 800 mPa·s, 850 mPa·s, 900 mPa·s, 1000 mPa·s, 1200 mPa·s, 1500 mPa·s, 2000 mPa·s, or 2500 mPa·s, or any two of the above values ​​as endpoints. Furthermore, the dynamic viscosity of the mixture of raw materials for the resin matrix is ​​controlled to be 300 mPa·s to 2500 mPa·s at 50°C.

[0105] Furthermore, the injection pressure is 2MPa~3MPa. For example, it can be 2MPa, 2.2MPa, 2.5MPa, 2.6MPa, 2.8MPa, or 3MPa, or any two of the above values ​​as endpoints. Furthermore, the injection rate is 50mL / min~100mL / min. For example, it can be 50mL / min, 60mL / min, 70mL / min, 75mL / min, 80mL / min, 90mL / min, or 100mL / min, or any two of the above values ​​as endpoints.

[0106] Furthermore, the curing process includes sequential treatment at 120℃~140℃ for 3h~5h, at 150℃~170℃ for 1h~3h, and at 180℃~220℃ for 3h~5h. This sequential heating method promotes uniform curing, resulting in a resin matrix with good curing uniformity, which is beneficial for improving the material properties uniformity of the battery box.

[0107] As an example, the curing process includes sequential treatment at 130°C for 4 hours, at 160°C for 2 hours, and at 200°C for 4 hours.

[0108] In this application, unless otherwise specified, "cell battery" refers to the basic unit capable of converting chemical energy into electrical energy, and generally includes at least a positive electrode, a negative electrode, and an electrolyte. During the charging and discharging process of the battery, active ions move back and forth between the positive and negative electrode plates, inserting and extracting. The electrolyte acts as a conductor for the active ions between the positive and negative electrode plates.

[0109] This application does not impose any particular limitation on the shape of the battery cell; it can be cylindrical, square, or any other arbitrary shape. For example, Figure 4 The battery cell shown is an example of a square-structured battery cell.

[0110] In some embodiments, the battery cell may include an outer packaging. This outer packaging can be used to encapsulate the electrode assembly and electrolyte described above. In some embodiments, the outer packaging of the battery cell may be a rigid shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer packaging of the battery cell may also be a flexible package, such as a pouch. The material of the flexible package may be plastic; further, non-limiting examples of plastic may include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0111] In some of these embodiments, reference is made to Figure 5 The outer packaging may include a housing 51 and a cover 53. The housing 51 may include a base plate and side plates connected to the base plate, the base plate and side plates forming a receiving cavity. The housing 51 has an opening communicating with the receiving cavity, and the cover 53 can be placed over the opening to close the receiving cavity. The positive electrode, negative electrode, and separator may be formed into an electrode assembly 52 by a winding process or a stacking process. The electrode assembly 52 is encapsulated within the receiving cavity. Electrolyte is immersed in the electrode assembly 52. ​​The number of electrode assemblies 52 contained in the battery cell 5 may be one or more, which can be selected by those skilled in the art according to actual needs.

[0112] Typically, a battery cell 5 includes a positive electrode, a negative electrode, an electrolyte, and a separator. During charging and discharging, active ions move back and forth between the positive and negative electrodes, inserting and releasing. The electrolyte acts as a conductor of ions between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, primarily prevents short circuits between the positive and negative electrodes while allowing ions to pass through.

[0113] Positive electrode sheet

[0114] The positive electrode includes a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector, the positive electrode film layer including a positive electrode active material.

[0115] As a non-limiting example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0116] In some embodiments, the positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector can be obtained by forming a metal material on a polymer material substrate. Non-limiting examples of the metal material in the positive electrode current collector may include one or more of aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Non-limiting examples of the polymer material substrate in the positive electrode current collector may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0117] In some embodiments, the positive electrode active material may be a known positive electrode active material for batteries. As a non-limiting example, the positive electrode active material may include one or more of the following materials: lithium-containing phosphates with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium transition metal oxides include, but are not limited to, one or more of lithium cobalt oxides (such as LiCoO2), lithium nickel oxides, lithium manganese oxides, lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides, lithium nickel cobalt aluminum oxides, and their modified compounds. Non-limiting examples of lithium-containing phosphates with an olivine structure include, but are not limited to, one or more of lithium iron phosphate, lithium iron phosphate and carbon composites, lithium manganese phosphate, lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium manganese iron phosphate and carbon composites.

[0118] Non-limiting examples of lithium cobalt oxides may include LiCoO2; non-limiting examples of lithium nickel oxides may include LiNiO2; non-limiting examples of lithium manganese oxides may include LiMnO2, LiMn2O4, etc.; non-limiting examples of lithium nickel cobalt manganese oxides may include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 Examples of lithium nickel cobalt aluminum oxides include LiNi, etc. 0.8 Co 0.15 Al 0.05 O2.

[0119] Understandably, lithium (Li) is intercalated and deintercalated during the charging and discharging process of a battery, and the Li content in the positive electrode active material varies depending on the state of discharge. In the examples of positive electrode active materials listed in this application, unless otherwise specified, the Li content refers to the initial state of the material. When positive electrode active materials are applied to the positive electrode sheet in a battery system, the Li content in the positive electrode active material typically changes after charge-discharge cycles. The Li content can be measured using molar content, but is not limited to this. Regarding "Li content refers to the initial state of the material," the initial state of the material refers to its state before being added to the positive electrode slurry. It is understood that new materials obtained by appropriately modifying the listed positive electrode active materials are also within the scope of positive electrode active materials. The aforementioned appropriate modification refers to acceptable modification methods for positive electrode active materials, and non-limiting examples include coating modification.

[0120] In the examples of positive electrode active materials in this application, the oxygen (O) content is only a theoretical value. Lattice oxygen release will cause changes in the molar content of oxygen, and the actual O content will fluctuate. The O content can be measured in molar content, but is not limited to this.

[0121] In some embodiments, the positive electrode active material layer may optionally include a binder. As a non-limiting example, the binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), PVDF-tetrafluoroethylene-propylene terpolymer, PVDF-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resins.

[0122] In some embodiments, the positive electrode active material layer may optionally include a conductive agent. As a non-limiting example, the conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0123] In some embodiments, the positive electrode sheet can be prepared by dispersing the components used to prepare the positive electrode sheet, such as the positive active material, conductive agent, binder, and any other components, in a solvent to form a positive electrode slurry; coating the positive electrode slurry onto at least one surface of the positive electrode current collector, and then obtaining the positive electrode sheet after drying, cold pressing, and other processes. The solvent can be selected from, but is not limited to, any of the solvents in the foregoing embodiments, such as N-methylpyrrolidone (NMP). The surface of the positive electrode current collector coated with the positive electrode slurry can be a single surface of the positive electrode current collector or both surfaces of the positive electrode current collector. The solid content of the positive electrode slurry can be 40wt% to 80wt%.

[0124] Negative electrode sheet

[0125] The negative electrode sheet includes a negative current collector. Further, the negative electrode sheet may also include a negative active material layer disposed on at least one surface of the negative current collector, the negative active material layer comprising a negative active material.

[0126] As a non-limiting example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0127] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. The composite current collector may include a polymeric material substrate and a metal layer formed on at least one surface of the polymeric material substrate. The composite current collector can be obtained by forming a metal material on the polymeric material substrate. Non-limiting examples of the metal material in the negative electrode current collector may include one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Non-limiting examples of the polymeric material substrate in the negative electrode current collector may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0128] In some embodiments, the negative electrode active material may be a negative electrode active material known in the art for use in batteries. As a non-limiting example, the negative electrode active material may include one or more of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may include one or more of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may include one or more of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0129] In some embodiments, the negative electrode active material layer may optionally include a binder. The binder may include one or more of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0130] In some embodiments, the negative electrode active material layer may optionally include a conductive agent. The conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0131] In some embodiments, the negative electrode active material layer may also optionally include other additives, such as thickeners (e.g., sodium carboxymethyl cellulose (CMC-Na)).

[0132] In some embodiments, the negative electrode sheet can be prepared by dispersing the components used to prepare the negative electrode sheet, such as the negative electrode active material, conductive agent, binder, and any other components, in a solvent (a non-limiting example of a solvent is deionized water) to form a negative electrode slurry; coating the negative electrode slurry onto at least one surface of the negative electrode current collector, and then obtaining the negative electrode sheet after processes such as drying and cold pressing. The surface of the negative electrode current collector coated with the negative electrode slurry can be a single surface of the negative electrode current collector or both surfaces of the negative electrode current collector.

[0133] electrolytes

[0134] Electrolytes function to conduct ions between the positive and negative electrode plates. This application does not impose any particular restrictions on the type of electrolyte; it can be selected according to requirements. For example, the electrolyte can be liquid, gel, or completely solid.

[0135] In some embodiments, the electrolyte is an electrolyte solution. The electrolyte solution includes an electrolyte salt and a solvent.

[0136] In some embodiments, the electrolyte salt may include one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluorophosphate (LiPO2F2), lithium difluorooxalate borate (LiDFOB), lithium dioxalate borate (LiBOB), lithium difluorodioxalate phosphate (LiDFOP), and lithium tetrafluorooxalate phosphate (LiTFOP).

[0137] In some embodiments, the solvent includes at least one of ether solvents, ester solvents, and sulfone solvents.

[0138] As an example, the ether solvent may include at least one of ethylene glycol dimethyl ether (DME), diethylene glycol dimethyl ether (DEGDME), triethylene glycol dimethyl ether (TRGDME), tetraethylene glycol dimethyl ether (TEGDME), and 1,3-dioxolane (DOL);

[0139] As an example, the ester solvent may include at least one of ethylene carbonate (EC), propylene carbonate (PC), butene carbonate (BC), vinylene carbonate (VC), fluoroethylene carbonate (FEC), methyl ethyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), γ-butyrolactone (BL), 1,3-propanesulfonate lactone (1,3-PS), methyl propionate (MP), methyl butyrate (MB), ethyl acetate (EA), ethyl propionate (EP), propyl propionate (PP), and ethyl butyrate (EB).

[0140] In some embodiments, the electrolyte may optionally include additives. For example, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain battery performance, such as additives that improve battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.

[0141] In some embodiments, the additives in the electrolyte may include, but are not limited to, one or more of fluoroethylene carbonate (FEC), difluoroethylene carbonate (DFEC), trifluoromethyl ethylene carbonate (TFPC), etc.

[0142] Separating membrane

[0143] In some embodiments, the battery cell also includes a separator. This application does not impose any particular limitation on the type of separator; any known porous separator with good chemical and mechanical stability can be selected.

[0144] In some embodiments, the material of the separator may include one or more of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer may be the same or different, without particular limitation.

[0145] In some embodiments, the thickness of the isolation membrane is 6 μm to 40 μm, and optionally 12 μm to 20 μm.

[0146] In some embodiments, the positive electrode, negative electrode, and separator can be fabricated into an electrode assembly using a winding process or a stacking process.

[0147] In another aspect, this application provides an electrical device comprising at least one of the above-described battery, the above-described battery case, and the battery case prepared by the above-described preparation method.

[0148] The aforementioned battery can be a power source for an electrical device or an energy storage unit for that device. Electrical devices can include, but are not limited to, mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, etc. Mobile devices can be, for example, mobile phones, laptops, etc.; electric vehicles can be, for example, pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc., but are not limited to these.

[0149] Figure 6 Here is an example of an electrical device 6. This electrical device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.

[0150] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the application will be further described in detail below with reference to embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its applications. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0151] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0152] Example 1

[0153] 1. Prepare the resin matrix mixture. Weigh the materials according to the mass ratio of thermosetting resin: functional filler: silane coupling agent of 100:10:1; the thermosetting resin is benzoxazine resin; the functional filler is hollow glass microspheres with a Dv50 particle size of 40 micrometers; the silane coupling agent is 3-glycidylpropyltrimethoxysilane; mix the above materials evenly at 50°C, and the dynamic viscosity of the mixed resin matrix mixture is 850 mPa·s.

[0154] 2. Reinforcing fiber layer. Carbon fiber plain weave fabric made from carbon fiber is selected as the reinforcing fiber layer. The tensile strength of carbon fiber plain weave fabric is 3520MPa and the tensile elastic modulus is 230GPa.

[0155] 3. RTM process for manufacturing battery boxes.

[0156] The RTM-EP injection testing machine was used.

[0157] 1) Completely lay the reinforcing fiber layer into the mold cavity of the injection molding machine, forming a cuboid shape similar to the mold cavity. Trim the edges neatly, and click to close and lock the mold. Using 100 parts by mass of thermosetting resin, the mass ratio of thermosetting resin: reinforcing fiber layer: functional filler: silane coupling agent is shown in Table 1. Weigh the materials. The mass ratio K in Table 1 refers to the mass ratio of thermosetting resin: reinforcing fiber layer: functional filler: silane coupling agent.

[0158] 2) Seal the mold and preheat the resin curing agent tank and mold of the RTM-EP injection testing machine to 50°C. Adjust the injection pressure to 2.2MPa. Mix the material weighed in step 1 in the resin curing agent tank to obtain the resin matrix mixture. Inject the mixture into the mold cavity obtained in step 1) at an injection rate of 75mL / min. Stop the injection when the mixture overflows from the vent holes of the mold and there are no more air bubbles.

[0159] 3) Set the appropriate curing temperature and adopt a staged curing process: sequentially raise the temperature to 130℃ for 4 hours, at 160℃ for 2 hours, and at 200℃ for 4 hours to complete the curing.

[0160] 4) After demolding and product trimming, the lower body of the battery box can be obtained.

[0161] 5) Prepare the upper casing of the battery box using the same preparation method as in steps 1-3; the upper and lower casings are fitted together to form a battery box with a receiving cavity for accommodating individual battery cells. The wall thickness of the upper and lower casings is 2 mm.

[0162] Examples 2-5

[0163] Examples 2-5 are basically the same as Example 1, except that the mass ratio K of thermosetting resin: reinforcing fiber layer: functional filler: silane coupling agent in step 1 is different, as shown in Table 1.

[0164] Examples 6-7

[0165] Examples 6 and 7 are basically the same as Example 1, except that the Dv50 particle size of the hollow glass microspheres in Examples 6 and 7 is different, as shown in Table 2.

[0166] Comparative Example 1

[0167] Comparative Example 1 is basically the same as Example 1, except that the functional filler is omitted in step 1, as shown in Table 1.

[0168] Comparative Example 2

[0169] Comparative Example 2 is basically the same as Example 1, except that the silane coupling agent is omitted in step 1, as shown in Table 1.

[0170] Comparative Example 3

[0171] Comparative Example 3 is basically the same as Example 1, except that the quality of the added reinforcing fiber layer is different (specifically, two reinforcing fiber layers from Example 1 are stacked together), as shown in Table 1.

[0172] The following is a performance test.

[0173] 1. Tensile strength test.

[0174] The wall material of the upper body of the prepared battery box was taken and cut using a universal sample preparation machine WZY-240 according to the requirements of GB / T 1447-2005 "Test Method for Tensile Properties of Fiber Reinforced Plastics" and GB / T 1446-2005 "General Rules for Test Method for Tensile Properties of Fiber Reinforced Plastics". Multiple sets of performance tests were conducted using a universal testing machine. The test specimen dimensions were 250mm × 25mm × D, the testing rate was 5mm / min, and the applied load was 20kN. The cut specimen was then fixed on a mold, and the testing equipment was started to test the tensile properties, obtaining the tensile strength.

[0175] 2. Impact performance test.

[0176] Carbon fiber composite specimens used for impact performance testing were prepared in accordance with GB / T 1451-2005 "Test Method for Impact Toughness of Fiber Reinforced Plastics by Simply Supported Beam". The impact performance of the carbon fiber composite material was tested using an impact testing machine to obtain the impact toughness results.

[0177] 3. Relative permittivity test.

[0178] The measurements are performed according to GB / T 31838.6-2021 "Dielectric and resistive properties of solid insulating materials - Part 6: Dielectric properties (AC method) - Relative permittivity and dielectric loss factor (frequency 0.1Hz~10MHz)".

[0179] Table 1 shows some parameters and performance results of Examples 1-5 and Comparative Examples 1-3.

[0180] Table 1

[0181]

[0182] As shown in the table above, the functional fillers and silane coupling agents were omitted in Comparative Examples 1 and 2, respectively, resulting in significantly lower tensile strength and impact resistance compared to the examples. In Comparative Example 3, the amount of reinforcing fiber layer added was excessive; although the tensile strength was acceptable, its impact resistance was low.

[0183] The embodiments of this application employ a specific component ratio, resulting in a material with good tensile strength and impact resistance, as well as a low dielectric constant.

[0184] Table 2 shows some parameters and performance results of Examples 1, 6-7.

[0185] Table 2

[0186]

[0187] As can be seen from the table above, the functional filler in the battery box of this application is hollow glass microspheres with a Dv50 particle size of 40 micrometers to 110 micrometers. The resulting material has good tensile strength and impact resistance, as well as a low dielectric constant. Optionally, the Dv50 particle size of the hollow glass microspheres is 30 micrometers to 50 micrometers.

[0188] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0189] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery box characterized by, The component material comprises a resin matrix and a reinforcing fiber layer arranged in the resin matrix, components of the resin matrix include a thermosetting resin, a functional filler and a silane coupling agent, the functional filler is dispersed in the thermosetting resin; in the component material, the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler and the silane coupling agent is 100: (20-60): (1-20): (0.1-2).

2. The battery pack of claim 1, wherein, In the component material, the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler and the silane coupling agent is 100: (30-40): (5-15): (0.5-1.5).

3. The battery box according to any one of claims 1 to 2, wherein One or more of the following conditions are met: (1) the fibers in the reinforcing fiber layer include one or more of plant fibers, aramid fibers, basalt fibers, polyester fibers, polyethylene fibers, polypropylene fibers, nylon fibers, glass fibers and carbon fibers; (2) the reinforcing fiber layer includes one or more of a fiber mat and a fiber cloth; (3) the thickness of a single reinforcing fiber layer is 0.10-0.50 mm; (4) the wall thickness of the battery box is 1.5-3 mm.

4. The battery box according to any one of claims 1 to 3, wherein The thermosetting resin includes one or more of epoxy resin, benzoxazine resin, phenolic resin, thermosetting polyimide resin, bismaleimide resin, polyester resin, vinyl ester resin, cyanate ester resin and derivatives thereof.

5. The battery box according to any one of claims 1 to 4, wherein The functional filler includes one or more of hollow glass microbeads, calcium carbonate, aluminum hydroxide, aluminum oxide and mica.

6. The battery pack of claim 5, wherein, The Dv50 particle size of the hollow glass microbeads is 10-110 microns.

7. The battery box according to any one of claims 1 to 6, wherein The silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, 3-glycidylpropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, 3-aminopropyltrimethoxysilane and isobutyltriethoxysilane.

8. The battery box according to any one of claims 1 to 7, wherein The battery box includes an upper box body and a lower box body, the upper box body can be covered on the lower box body and cooperates with the lower box body to form a containing cavity, the component material of at least one of the upper box body and the lower box body includes the resin matrix and the reinforcing fiber layer arranged in the resin matrix.

9. The battery pack of claim 8, wherein, Both the upper box body and the lower box body include a box bottom plate and a box side plate connected to the box bottom plate, the component material of the box bottom plate and the box side plate both includes the resin matrix and the reinforcing fiber layer, the reinforcing fiber layers in the box bottom plate and the box side plate are integrated structures.

10. A battery, characterized by The battery includes a battery monomer and a battery box as claimed in any one of claims 1-9, the battery monomer is arranged in the battery box.

11. A method of producing a battery case, characterized by, The method comprises the following steps: arranging a reinforcing fiber layer in the cavity of a mold; A raw material of the resin matrix is injected into a cavity of the mold, and a curing process is performed to form the resin matrix, and the mold is demolded; wherein the components of the resin matrix include a thermosetting resin, a functional filler, and a silane coupling agent, the functional filler is dispersed in the thermosetting resin, and the mass ratio of the thermosetting resin, the reinforcing fiber layer, the functional filler, and the silane coupling agent is 100: (20-60): (1-20): (0.1-2).

12. The method for preparing the battery box as described in claim 11, characterized in that, One or more of the following conditions are met: (1) the injecting step uses resin transfer molding technology; (2) in the injecting step, the preheating temperature of the raw material of the resin matrix and the mold is 40-60°C; (3) the injection pressure of the injecting step is 2-3 MPa, and the injection rate is 50-100 mL / min; (4) the curing process includes sequentially treating at 120-140°C for 3-5 h, at 150-170°C for 1-3 h, and at 180-220°C for 3-5 h; (5) the dynamic viscosity of the mixture of the raw material of the resin matrix at 40-60°C is 300-2500 mPa·s.

13. An electrical device, characterized by At least one of the battery box according to any one of claims 1-9, the battery according to any one of claim 10, and the battery box prepared by the preparation method according to any one of claims 11-12.

Images