Battery pack
The battery pack design with a notched insulating element and specific a/h ratio ensures strong adhesion and insulation, addressing the challenge of simultaneous adhesive and insulation performance, enhancing safety and structural integrity.
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Utility models
- Current Assignee / Owner
- CALB GROUP CO LTD
- Filing Date
- 2026-04-21
- Publication Date
- 2026-06-11
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[0001] The present application is a divisional application; the number of the original application is 2025105681125, the filing date is 30 April 2025 and the title of the invention is ‘Battery pack’. Technical field
[0002] The present invention relates to the technical field of batteries, in particular a battery pack. State of the art
[0003] A battery pack typically consists of a housing and several batteries arranged within it. The bottom of the battery is bonded to the base plate of the housing using an adhesive to increase the overall strength of the battery pack and prevent its rigidity from being compromised under vibration conditions.
[0004] Currently, the battery surface is encased in an insulating element. To ensure sufficient bond strength between the battery and the base plate of the housing, the metal housing typically protrudes on the side of the insulating element facing the base plate, allowing it to be bonded to the base plate and thus achieving sufficient adhesive strength between the battery and the base plate. However, this configuration carries the risk of insulation failure between the battery and the housing. Content of the invention
[0005] The purpose of the present invention is to provide a battery pack that solves the problem existing in the prior art that insulation performance and adhesive strength cannot be guaranteed simultaneously.
[0006] According to the above concept, the technical solution of the present invention consists of: a battery pack comprising a battery, an adhesive layer and a base plate, wherein the base plate serves to support the battery, the adhesive layer is located between the battery and the base plate and serves to firmly connect the base plate to the battery, characterized in that the battery comprises a battery housing body and an insulating element that encloses the surface of the battery housing body, wherein the insulating element has a notch, the notch causing the base surface of the battery housing body to be at least partially exposed on the side facing the base plate, wherein the adhesive layer is arranged at least partially at the notch and is bonded to the base plate, wherein an insulating layer is arranged between the base plate and the adhesive layer, wherein an orthogonal projection of the edge of the notch onto the base plate coincides with an orthogonal projection of the insulating layer onto the base plate; where a ratio between an area S1 of the notch of the insulating element and a total area S2 of the surface of the battery housing body enclosed by the insulating element is a, i.e. a = S1 / S2, where the minimum distance of the battery housing body located at the notch to the base plate is h mm, and a and h satisfy the following relationship: 0.1 ≤ a / h ≤ 0.13.
[0007] The technical solution described above has at least the following advantages: Applying an insulating layer to the baseplate increases the insulating strength between the area of the battery casing corresponding to the notch and the baseplate. However, this insulating layer makes machining the baseplate more difficult and reduces the bond strength between the baseplate and the battery. Therefore, by adjusting the a / h value to satisfy the aforementioned relationship, both good bond strength between the battery and the baseplate are ensured, and short circuits between the baseplate and the battery are prevented, thus increasing the overall structural strength and safety performance of the battery pack. If the a / h value is too high, the exposed metal surface area of the battery casing increases, raising the risk of a short circuit between the battery casing and the baseplate.This leads to a deterioration of the insulation performance between the two components and thus to a short circuit between the battery and the base plate, which impairs the battery's safety performance. If the a / h value is too low, this results in an insufficient adhesive surface area between the battery housing and the base plate, as well as an excessive gap between the battery housing and the base plate, resulting in weak adhesion between the battery and the base plate. Under vibration conditions, there is a risk of the battery pack detaching, which compromises the overall strength of the battery pack and its operational safety. Illustration of the attached figures
[0008] To better illustrate the technical solutions in the embodiments of the present invention, the drawings necessary for describing these embodiments are briefly presented below. It goes without saying that the drawings described below represent only some embodiments of the present invention. A person skilled in the art can easily create further drawings based on the content of the embodiments and these drawings. Fig. Figure 1 is a schematic representation of the structure of a battery pack according to an embodiment of the present invention; Fig. 2 is a schematic cross-sectional representation of a battery pack according to an embodiment of the present invention; Fig. 3 is an enlarged view of the in Fig.2 area A shown according to an embodiment of the present invention; Fig. Figure 4 is a schematic representation of the structure of a battery according to an embodiment of the present invention; Fig. Figure 5 is an exploded view of a battery according to an embodiment of the present invention; Fig. 6 is a view from below of a battery according to an embodiment of the present invention; Fig. 7 is a view from below of another battery according to an embodiment of the present invention; Fig. 8 is a view from below of another battery according to an embodiment of the present invention; Fig. 9 is a view from below of another battery according to an embodiment of the present invention; Fig.Figure 10 is an enlarged partial view of the cross-section of a battery pack according to an embodiment of the present invention; Fig. Figure 11 is a three-dimensional representation of a battery according to an embodiment of the present invention; Fig. 12 is a main view of a battery according to an embodiment of the present invention; Fig. Figure 13 is an enlarged partial view of the cross-section of another battery pack according to an embodiment of the present invention.
[0009] In the characters: 100. Battery; 110. Battery casing body; 111. Base surface; 112. Side surface; 113. Top surface; 120. Insulating element; 121. Notch; 122. First insulating section; 123. Second insulating section; 124. Opening; 130. Explosion protection valve; 140. Electrode stack; 150. Cell; 200. Adhesive layer; 300. Base plate; 400. Insulating layer; 500. Frame structure; 510. Side frame; 520. Cross member; 530. Longitudinal member; 10. Outer casing body; 101. Battery compartment; X. First direction. Specific embodiment
[0010] To better explain the technical problems to be solved by the present invention, the technical solutions applied, and the resulting technical effects, the technical solution of the present invention will be explained in more detail below with reference to the accompanying drawings and detailed embodiments. It is understood that the detailed embodiments described here serve only to illustrate the present invention and do not limit it. It should also be noted that, for the sake of clarity, the accompanying drawings show only the parts relevant to the present invention and not all parts.
[0011] It is understood that the term "an embodiment" used throughout this description means that the specific features, structures, or properties associated with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrase "in an embodiment," which appears at various points throughout this description, does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or properties may be combined in any way in one or more embodiments.
[0012] It should be noted that similar markings and letters represent similar items in subsequent drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.
[0013] In the description of the present invention, the terms "connect," "couple," and "fasten" are to be interpreted broadly unless expressly stated and defined otherwise. They may, for example, denote a permanent connection, a detachable connection, or an integral structure; they may refer to a mechanical connection or an electrical connection; they may signify a direct connection or an indirect connection via an intermediate medium; and they may represent the internal connectivity between two components or an interactive relationship between two components. The specific meaning of the above terms in the context of the present invention will be readily apparent to a person skilled in the art.
[0014] In the present invention, an arrangement of a first feature "above" or "below" a second feature may include direct contact between the first and second features, or it may include the first and second features not being in direct contact, but being connected by another feature between them, unless explicit provisions and limitations apply. Furthermore, an arrangement of a first feature "above," "above," and "on" a second feature may include the first feature being located directly above or obliquely above the second feature, or it may simply indicate that the horizontal height of the first feature is greater than that of the second feature.The arrangement of a first feature “below,” “underneath,” and “below” a second feature implies that the first feature lies directly below or obliquely below the second feature, or it simply indicates that the horizontal height of the first feature is lower than that of the second feature. Unless otherwise specified in the description of this embodiment, “several” specifically refers to two or more features.
[0015] In the description of this embodiment, the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "top," "bottom," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., refer to the directions or positions shown in the accompanying drawings and serve only to clarify and simplify the description, not as an indication or suggestion that the device or component in question has a specific orientation, must be designed in a specific orientation, or must be operated in a specific orientation. They are therefore not to be understood as limiting the present invention. Furthermore, the terms "first" and "second" serve only for differentiation in the description and have no special meaning.
[0016] It should be noted that when an element is described as "attached to another element" or "arranged on another element", it may either be located directly on that other element or may include an intermediate element.
[0017] The technical solution of the present invention will now be explained in more detail with reference to the drawings and by means of detailed embodiments.
[0018] This embodiment provides a battery pack that ensures both the connection strength between the battery and the base plate and the insulation performance.
[0019] For example, the battery pack includes, as shown in Fig.Figure 1 shows a typical outer housing 10 and several batteries 100 arranged within the outer housing 10, the batteries 100 being arranged in groups within the outer housing 10. The outer housing 10 generally comprises a base plate 300, a frame structure 500, and a housing cover (not shown in the figure). The frame structure 500 comprises a side frame 510, a cross member 520, and a longitudinal member 530. The side frame 510 is connected between the base plate 300 and the housing cover and forms a battery compartment. The cross member 520 and the longitudinal member 530 are connected crosswise within the battery compartment and divide the battery compartment into several battery sub-compartments 101, with several batteries 100 being arranged in each of the battery sub-compartments 101. Optionally, both the cross member 520 and the longitudinal member 530 can be present only once or multiple times.This embodiment contains no such limitation.
[0020] Optionally, the battery 100 can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium-metal battery, a sodium-metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc. This embodiment is not limited to these. A battery 100 typically comprises a battery housing 110, a cell assembly (not shown in the figure), and an electrolyte solution (not shown in the figure). The battery housing 110 serves to accommodate the cell assembly and the electrolyte solution. The battery housing 110 is provided with at least one positive electrode column and at least one negative electrode column.The cell assembly comprises one or more electrode assemblies, wherein the electrode assembly consists of a positive electrode sheet, a negative electrode sheet and a separator, which are stacked or wound.
[0021] The positive electrode array can generally comprise a positive electrode current collector and a positive electrode active layer, with the positive electrode active layer being applied directly or indirectly to the positive electrode current collector. The positive electrode current collector without a positive electrode active layer extends beyond the positive electrode current collector with the positive electrode active layer. The positive electrode current collector without a positive electrode active layer serves as a positive electrode tab, and several positive electrode tabs are stacked on top of each other and electrically connected to the positive electrode column. For example, several stacked positive electrode tabs can be welded directly to the positive electrode column to establish an electrical connection.Alternatively, the cell assembly can also include a positive transfer plate, wherein the multiple stacked positive electrode tabs are welded to one end of the positive transfer plate and the other end of the positive transfer plate is welded to the positive electrode column, so that the positive electrode tabs form an electrical connection with the positive electrode column.
[0022] The negative electrode array can generally comprise a negative electrode current collector and a negative electrode active layer, with the negative electrode active layer being applied directly or indirectly to the negative electrode current collector. The negative electrode current collector without a negative electrode active layer extends beyond the negative electrode current collector with the negative electrode active layer. The negative electrode current collector without a negative electrode active layer serves as a negative electrode tab, and several negative electrode tabs are stacked on top of each other and electrically connected to the negative electrode column. For example, several stacked negative electrode tabs can be welded directly to the negative electrode column to create an electrical connection.Alternatively, the cell assembly can also include a negative transfer plate, wherein the multiple stacked negative electrode tabs are welded to one end of the negative transfer plate and the other end of the negative transfer plate is welded to the negative electrode column, so that the negative electrode tabs form an electrical connection with the negative electrode column. The separator material is arbitrary, for example, polypropylene or polyethylene, etc.
[0023] Optionally, the outer box body can be composed of a base plate 300 and a side plate connected to the base plate. That is, as in the Fig. 2 and Fig.As shown in Figure 3, the battery pack also includes a base plate 300, which serves to support the battery 100. The battery 100 is firmly connected to the base plate 300 via the adhesive layer 200. More precisely, the adhesive layer 200 is located between the battery 100 and the base plate 300 and serves to firmly connect the base plate 300 and the battery 100.
[0024] In this embodiment, the battery comprises a battery housing body 110 and an insulating element 120 that surrounds the surface of the battery housing body 110. The insulating element 120 serves to insulate the battery housing body 110 from the outside environment. It should be noted that the insulating element 120 is rigidly connected to the battery housing body 110. Both are joined to form a single unit, so that the insulating element 120 cannot move relative to the battery housing body 110.
[0025] Optionally, the insulating element 120 comprises an insulating protective film and / or an insulating protective coating; that is, the insulating element 120 can comprise exclusively an insulating protective film; it can also comprise exclusively an insulating protective coating; or it can comprise both an insulating protective film and an insulating protective coating, in which case the insulating protective film and the insulating protective coating can be arranged one above the other. It is also possible for part of the insulating element 120 to be designed as an insulating protective film and another part as an insulating protective coating. The specific choice is flexible. This embodiment contains no restrictions in this regard.
[0026] It should be noted that the insulating protective film can be applied to the battery housing body 110 by gluing. The insulating protective coating can be applied to the battery housing body 110 by coating, and this embodiment does not impose any restrictions in this regard.
[0027] For example, the insulating protective film consists of polyethylene terephthalate, polyimide, polypropylene, etc. Materials suitable for the insulating protective coating include polyacrylates, silicones, polyurethanes, epoxy resins, etc. This embodiment does not impose any restrictions in this regard. For example, the insulating protective film could be a blue film.
[0028] In this embodiment, the insulating element 120 has a notch 121. More precisely, the notch 121 is located in the area between the base surface 111 of the insulating element 120, which is situated on the side of the battery housing body 110 facing the base plate 300, and the base plate 300, such that the notch 121 causes the base surface 111 of the battery housing body 110 to be at least partially exposed on the side facing the base plate 300. The adhesive layer 200 is at least partially located at the notch 121 and bonded to the base plate 300, thereby improving the adhesive strength and reliability of the connection between the battery housing body 110 and the base plate 300.
[0029] It should be noted that the insulating material covering the outer surface of the battery 100 (or the battery housing body 110) consists of the insulating element 120; that is, the insulating material covering the outer surface of the battery 100 (or the battery housing body 110) except for the opening facing the base plate 300 is the insulating element 120; in other words: any insulating material covering the outer surface of the battery 100 (or the battery housing body 110) is the insulating element 120.
[0030] In this embodiment and as in the Fig. 2 and Fig.As shown in Figure 3, an insulating layer 400 is arranged between the base plate 300 and the adhesive layer 200. The insulating layer 400 serves to improve the insulating performance between the battery housing body 110 and the base plate 300. The orthogonal projection of the notch 121 onto the base plate 300 falls within the orthogonal projection of the insulating layer 400 onto the base plate 300. This means that the orthogonal projection of the notch 121 onto the base plate 300 lies entirely within the orthogonal projection of the insulating layer 400 onto the base plate 300. This, in turn, means that the orthogonal projection of the notch 121 onto the insulating layer 400 lies entirely on the insulating layer 400 and has no part that lies outside the insulating layer 400.In this way, the part of the base surface 111 of the battery housing body 110 exposed by the notch 121 lies directly opposite the insulating layer 400 and not directly opposite the base plate 300, thereby increasing the insulating performance against the base plate 300 by the insulating layer 400.
[0031] In this embodiment, as in Fig. Figure 5 shows the ratio between the area S1 of the notch 121 of the insulating element 120 and the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120, denoted as a, i.e., a = S1 / S2. It is evident that in this embodiment, a can serve to denote the size of the battery housing body 110. As shown in Fig.As shown in Figure 3, the minimum distance between the battery housing body 110 at the notch 121 and the base plate 300 is h mm. That is, the minimum distance between the part of the base surface 111 of the battery housing body 110 opposite the notch 121 and the base plate 300 is h mm. Here, a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.13.
[0032] It should be noted that a / h can take any value between 0.01 and 0.13, or a range between any two values. This embodiment contains no such restriction. For example, the value of a / h can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, etc.
[0033] In some optional embodiments, the ratio between the area S1 of the notch 121 of the insulating element 120 and the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120 can also be understood as follows: the ratio of the area S1 of the notch 121 of the insulating element 120 to the area of the entire insulating element 120. It should be noted that the units for S1 and S2 in this embodiment are mm. 2 or other common units. This embodiment contains no such limitation.
[0034] In some optional embodiments, this embodiment provides a range of values for a. For example, the range of values for a is between 0.01 and 0.2. The value of a can be 0.01, 0.05, 0.08, 0.1, 0.12, 0.15, 0.18, 0.2, etc.
[0035] This example also provides a range of values for h. For instance, the range for h is between 0.7 and 3.8. The value of h can be 0.7, 1, 1.2, 1.5, 1.8, 2, 2.5, 2.8, 3, 3.5, 3.8, etc.
[0036] In this embodiment, a is the ratio between the area S1 of the notch 121 of the insulating element 120 and the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120. Therefore, the value of a determines the proportion of the area S1 of the notch 121 to the total area of the insulating element 120 on the surface of the battery housing body 110. This value is used to determine the contact condition between the battery housing body 110 and the base plate 300 in order to more accurately represent the risk of insulation failure of the battery housing body 110. It should be noted that the risk of insulation failure mentioned in this embodiment is to be understood as meaning that, in addition to metal-to-metal contacts, insulation failure can also occur if liquids such as condensation or electrolyte solution on the surface of the battery housing body 110 lead to a conductive contact.
[0037] By applying an insulating layer 400 to the base plate 300, the insulating strength between the area of the battery housing body 110 corresponding to the notch 121 and the base plate 300 is increased. However, the insulating layer 400 on the base plate 300 makes machining the base plate 300 more difficult overall and reduces the bond strength between the base plate 300 and the battery 100. Therefore, by regulating the a / h value to the range of 0.01 ≤ a / h ≤ 0.13, both good bond strength between the battery 100 and the base plate 300 is ensured, and short circuits between the base plate 300 and the battery 100 are prevented, thereby increasing the overall structural strength and safety performance of the battery pack.If the a / h value is too high, the exposed area of the metal battery housing 110 increases, thereby raising the risk of a short circuit between the battery housing 110 and the base plate 300. This leads to a deterioration of the insulation performance between the two components and thus to a short circuit between the battery 100 and the base plate 300, which impairs the safety performance of the battery 100 and the battery pack. If the a / h value is too low, this results in an insufficient adhesive surface area between the battery housing 110 and the base plate 300, as well as an excessive gap between the battery housing 110 and the base plate 300, resulting in weak adhesion between the battery 100 and the base plate 300. Under vibration conditions, there is a risk that the battery pack will detach, which compromises the overall strength of the battery pack and its operational safety.
[0038] Optionally, in this embodiment, the battery housing body 110 serves to accommodate the cell 150 and to insulate the cell 150 from the external environment. The battery housing body 110 can comprise a casing (not shown in the figure) and a cover plate (not shown in the figure), wherein the casing has an opening at one end and the cover plate is welded to the casing to close the opening and thus form a relatively sealed receiving space for the cell 150. Since the battery housing body 110 is made of metal such as aluminum or stainless steel, an insulating structure must be provided between the battery housing body 110 and the base plate 300 to ensure insulation.
[0039] For example, the base plate 300 is made of a metallic material. Thus, the base plate 300 can be made of aluminum, stainless steel, an aluminum alloy, iron, etc. This embodiment does not contain any restrictions in this regard.
[0040] In an optional embodiment, one of the following materials can be used for the insulating layer 400: polyethylene terephthalate, polyimide, mica, UV-coated material, or epoxy resin. The insulating layer 400 can be sprayed onto the surface of the base plate 300 facing the battery 100 or glued onto the surface of the base plate 300 facing the battery 100. This embodiment contains no such limitation.
[0041] In some optional embodiments and as shown in Fig.As shown in Figure 4, the area of the orthogonal projection of the notch 121 on the base plate 300 is smaller than the area of the base 111 of the battery housing body 110. In this case, a and h satisfy the following relationship: 0.05 ≤ a / h ≤ 0.13. It should be noted that the area of the orthogonal projection of the notch 121 on the base plate 300 is smaller than the area of the base 111 of the battery housing body 110. That is, the notch 121 does not completely expose the base 111 of the battery housing body 110, but only partially. Therefore, the bonding area between the battery 100 and the base plate 300 is relatively small, resulting in a lower bond strength between the battery 100 and the base plate 300. Therefore, reducing the distance between the battery 100 and the base plate 300 increases the connection strength between the two.
[0042] If the area of the orthogonal projection of the notch 121 on the base plate 300 is smaller than the area of the base 111 of the battery housing body 110, there are various possibilities for the relative positioning of the notch 121 to the base 111 of the battery housing body 110. In this embodiment, the following three embodiments are provided as examples.
[0043] In an optional embodiment and as in Fig.As shown in Figure 6, the edge of one end of the notch 121 coincides in the first direction with the edge of one end of the base 111 of the battery housing body 110 in the first direction. It should be noted that the edge of one end of the notch 121 coincides in the first direction with the edge of one end of the base 111 of the battery housing body 110 in the first direction. This can be understood to mean that the orthogonal projection of the edge of one end of the notch 121 onto the base plate 300 in the first direction coincides with, or lies on a line with, the orthogonal projection of the edge of one end of the base 111 of the battery housing body 110 onto the base plate 300 in the first direction.
[0044] It should also be noted that the first direction is the longitudinal or the lateral direction of the battery housing body 110. This embodiment contains no limitation in this respect. Fig. Figure 6 in this embodiment shows a schematic representation in which the first direction corresponds to the longitudinal direction of the battery housing body 110.
[0045] In another embodiment and as in Fig. As shown in Figure 7, the edges at both ends of the notch 121 in the first direction each coincide with the edges at both ends of the base 111 of the battery housing body 110 in the first direction. It should be noted that the edges at both ends of the notch 121 in the first direction each correspond to the edges at both ends of the base 111 of the battery housing body 110 in the first direction and are flush with each other in the vertical direction of the battery housing body 110.
[0046] In another embodiment and as in Fig.As shown in Figure 8, the edge of the notch 121 is spaced apart from the edge of the base 111 of the battery housing body 110. That is, the edge of the notch 121 does not extend to the edge of the base 111 of the battery housing body 110. Furthermore, the minimum value b for the distance between the edge of the notch 121 and the edge of the base 111 of the battery housing body 110 is in the range of 2 mm to 30 mm. In this way, the exposed area of the base 111 of the battery housing body 110 is relatively small when the edge of the notch 121 of the insulating element 120 is spaced apart from the edge of the base 111 of the battery housing body 110, thereby reducing the risk of a short circuit between the battery housing body 110 and the base plate 300.
[0047] For example, the minimum distance b between the edge of the notch 121 and the edge of the base 111 of the battery housing body 110 can be any value between 2 mm and 30 mm, or a range between any two values. This embodiment contains no such restriction. For example, the minimum distance b between the edge of the notch 121 and the edge of the base 111 of the battery housing body 110 is 2 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, 20 mm, 22 mm, 25 mm, 28 mm, 30 mm, etc.
[0048] It should be noted that in this optional embodiment the notch 121 can be located in the center of the surface of the insulating element 120 facing the base plate 300.
[0049] The battery packs of all three optional embodiments mentioned above meet the requirements for insulation performance between the battery 100 and the base plate 300, the requirements for connection strength between the battery 100 and the base plate 300, and the requirements for high energy density of the battery pack.
[0050] In further optional embodiments and as described in Fig.As shown in Figure 9, the area of the orthogonal projection of the notch 121 on the base plate 300 corresponds to the area of the base 111 of the battery housing body 110, where a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.1. This means that the base 111 of the battery housing body 110, which faces the base plate 300, is completely exposed and not covered by the insulating element 120.If the area of the orthogonal projection of the notch 121 on the base plate 300 corresponds to the area of the base surface 111 of the battery housing body 110, by regulating the range of a / h such that 0.01 ≤ a / h ≤ 0.1, both good adhesion between the battery 100 and the base plate 300 is ensured and the creepage distance between the battery housing body 110 and the base plate 300 is increased, thus ensuring that no short circuit occurs between the base plate 300 and the battery 100, which increases the structural strength and safety performance of the entire battery pack.
[0051] In some optional embodiments and as shown in Fig.As shown in Figure 10, the battery 100 also includes an explosion protection valve 130, which can be arranged on the base surface 111 of the battery housing body 110 facing the base plate 300. The explosion protection valve 130 serves to release the pressure of the gases contained in the battery 100 in the event of thermal runaway, which leads to a certain internal pressure, so that the hot gases can escape from the battery 100. The explosion protection valve 130 typically achieves pressure relief by creating a notch that serves as a weak point in the battery housing body 110. An escape bore is provided in the adhesive layer 200 at the location of the explosion protection valve 130 (shown in Figure 10).(not shown), to prevent the adhesive layer 200 from hindering the opening of the explosion protection valve 130, which would prevent the explosion protection valve 130 from releasing the pressure in a timely manner. The orthogonal projection of the explosion protection valve 130 onto the adhesive layer 200 lies within the escape bore, so that the arrangement of the adhesive layer 200 does not impede the opening and venting of the explosion protection valve 130. In this embodiment, the orthogonal projection of the explosion protection valve 130 onto the insulating element 120 lies within the notch 121, and a and h satisfy the following relationship: 0.03 ≤ a / h ≤ 0.13. It should be noted that the orthogonal projection of the explosion protection valve 130 onto the insulating element 120 is specifically such that the orthogonal projection of the explosion protection valve 130 onto the surface of the insulating element 120 facing the base plate 300 lies within the notch 121, i.e.The explosion protection valve 130 is located directly opposite the notch 121.
[0052] In this embodiment, the explosion protection valve 130 and the notch 121 are located on the same side of the battery 100, with the orthogonal projection of the explosion protection valve 130 onto the insulating element 120 lying within the notch 121. Since the explosion protection valve 130 must release the gases and pressure inside the battery housing 110 in a timely manner in the event of thermal runaway of the battery 100, it must not be blocked by the adhesive layer 200. By adjusting the a / h ratio so that the relationship 0.03 ≤ a / h ≤ 0.13 is satisfied, the adhesive area and bond strength between the adhesive layer 200 and the underside of the battery housing 110 can be ensured without impairing the insulating performance between the battery 100 and the base plate 300.
[0053] To ensure that the adhesive strength of the entire base 111 of the battery housing body 110 is not impaired by an excessively small adhesive area, thus preventing a weak point, the distance between the explosion protection valve 130 and the edge of the notch 121 must be adjusted in a direction perpendicular to the vertical direction of the battery housing body 110. For example, as shown in Fig.Figure 10 shows the minimum distance k between the edge of the explosion protection valve 130 and the edge of the notch 121 in a direction perpendicular to the vertical direction of the battery housing body 110 (i.e., in the longitudinal or lateral direction of the battery housing body 110) to be 0.2 mm to 5 mm. This creates a gap between the edge of the explosion protection valve 130 and the edge of the notch 121, which can be used to apply the adhesive layer 200 to improve the bond strength between the battery housing body 110 and the base plate 300, without the adhesive layer 200 impairing the function of the explosion protection valve 130.
[0054] For example, the value of the minimum distance k between the edge of the explosion protection valve 130 and the edge of the notch 121 in a direction perpendicular to the height direction of the battery housing body 110 can take any value between 0.2 mm and 5 mm, or a range between any two values. For example, the value of the minimum distance k between the edge of the explosion protection valve 130 and the edge of the notch 121 in a direction perpendicular to the height direction of the battery housing body 110 is 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.2 mm, 2.5 mm, 3 mm, 3.8 mm, 4 mm, 4.5 mm, 4.8 mm, 5 mm, etc.
[0055] In one embodiment, the explosion protection valve 130 is integrally formed with the battery housing body 110. This means that the battery housing body 110 has a weak point whose function is entirely identical to that of the explosion protection valve 130, so that the weak point can be considered the explosion protection valve 130 itself. The integrated design of the explosion protection valve 130 with the battery housing body 110 simplifies the manufacturing of the explosion protection valve 130, reduces the number of assembly steps for the battery, increases the assembly efficiency of the battery, and also expands the functionality of the battery housing body 110.
[0056] It goes without saying that the explosion protection valve 130 does not necessarily have to be formed integrally with the battery housing body 110, but that the battery housing body 110 can consist of two independent components, i.e., that the explosion protection valve 130 can be designed as a separate explosion protection valve. In this case, the connection between the explosion protection valve 130 and the battery housing body 110 can be made, for example, by welding. This embodiment contains no such limitation.
[0057] In an optional embodiment, a protective sticker for the explosion protection valve 130 (not shown in the figure) can be affixed to the side of the explosion protection valve 130 facing away from the battery housing body 110, since the explosion protection valve 130 is located directly opposite the notch 121. This further improves the insulating performance of the explosion protection valve 130. The protective sticker serves to protect the explosion protection valve 130 and prevents premature bursting of the explosion protection valve 130 before the breaking conditions are reached. It also prevents the explosion protection valve 130 from breaking due to external forces from outside the battery 100, thereby increasing the reliability of the explosion protection valve 130.
[0058] Optionally, the protective sticker of the explosion protection valve has the same insulating function as the insulating element 120. For example, the protective sticker of the explosion protection valve is made of an insulating material such as polytetrafluoroethylene, polyethylene terephthalate, polyethylene, polypropylene, polyimide, and similar materials. In this case, the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120 corresponds to the sum of the area of the insulating element 120 and the area of the protective sticker of the explosion protection valve. That is, the insulating element 120 encompasses the protective sticker of the explosion protection valve, or in other words: part of the insulating element 120 forms the protective sticker of the explosion protection valve.
[0059] It goes without saying that the explosion protection valve 130 does not necessarily have to be attached to the base surface 111 of the battery housing body 110, which faces the base plate 300, but can also be attached to another surface. In particular, as shown in Fig.As shown in Figure 11, the explosion protection valve 130 is arranged on the battery housing body 110, wherein the surface of the battery housing body 110 on which the explosion protection valve 130 is arranged differs from the surface of the battery housing body 110 that is opposite the notch 121. For example, the explosion protection valve 130 is arranged on the top surface of the battery housing body 110 on the side facing away from the base plate 300. In this way, the explosion protection valve 130 and the notch 121 are not on the same side of the battery 100, so that a short circuit between the battery 100 and the base plate 300 does not occur at the notch 121 when the explosion protection valve 130 is triggered, thus increasing the safety of the battery pack.
[0060] In an optional embodiment, the insulating element 120 on the explosion protection valve 130 has a deflection section (not shown in the figure), and a protective sticker for the explosion protection valve is arranged on the side of the explosion protection valve 130 that is away from the battery housing body 110. The protective sticker serves to protect the explosion protection valve 130. The material of the protective sticker is the same as described above, so that the protective sticker can be used for insulation between the battery 100 and the battery pack housing. In this case, the total surface area S2 of the battery housing body 110 enclosed by the insulating element 120 is the sum of the surface area of the insulating element 120 and the surface area of the protective sticker for the explosion protection valve.
[0061] In further embodiments, the insulating element 120 is arranged such that it encloses the explosion protection valve 130. This prevents a short circuit between the battery 100 and the outer casing of the battery pack caused by the bursting of the explosion protection valve 130, thereby increasing the operational safety of the battery pack.
[0062] Optionally, as in Fig.Figure 12 shows the surface of the battery housing body 110 adjacent to the base surface 111, which is designated as the side surface 112 of the battery housing body 110. In this embodiment, the insulating element 120 surrounds the side surface 112 of the battery housing body 110, with a gap between the insulating element 120 and the base surface 111 of the battery housing body 110, wherein the ratio of the length d1 of this gap in the vertical direction of the battery housing body 110 to the height d2 of the battery housing body 110 is in the range of 0.05 to 0.95, and a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.06.
[0063] It should be noted that the ratio of d1 to d2 must not be too large, as this would result in an excessively large exposed area of the battery housing body 110 and impair the insulation performance of the battery 100. In this embodiment, the ratio of d1 to d2 can take any value between 0.05 and 0.95, or any range between any two values. This embodiment contains no restrictions in this regard. For example, the ratio of d1 to d2 may be 0.05, 0.1, 0.3, 0.5, 0.6, 0.8, 0.9, 0.95, etc.
[0064] In one embodiment and as in Fig.As shown in Figure 11, the surface of the battery housing body 110 facing away from the base plate 300 can be referred to as the top surface 113 of the battery housing body 110. The insulating element 120 has an opening 124 in the area corresponding to the top surface 113 of the battery housing body 110, where a and h satisfy the following relationship: 0.03 ≤ a / h ≤ 0.13. Thus, the insulating element 120 does not completely enclose the top surface 113 of the battery housing body 110. The total area S2 of the insulating element 120 is relatively small, while the area S1 of the notch 121 constitutes a relatively large proportion of the base surface 111 of the insulating element 120. By limiting the value of a / h to the range 0.03 ≤ a / h ≤ 0.13, it is ensured that no short circuit occurs between the base plate 300 and the battery 100, while at the same time ensuring good adhesion between battery 100 and base plate 300.This increases the structural strength and safety performance of the battery pack. Furthermore, if the insulating element 120 does not enclose the cover surface 113 of the battery housing body 110, the efficiency with which the insulating element 120 encloses the battery housing body 110 is improved, thereby increasing the speed of grouping and assembling the battery 100.
[0065] In some optional embodiments, the opening 124 fully exposes the cover surface 113 of the battery housing body 110, thereby further increasing the speed of grouping and assembling the battery 100.
[0066] In other embodiments, the insulating element 120 can also enclose part of the cover surface 113 of the battery housing body 110; that is, the insulating element 120 is arranged on the cover surface 113 of the battery housing body 110. In an optional embodiment, and as in Fig.As shown in Figure 11, the insulating element 120 comprises a first insulating section 122 and a second insulating section 123, which are connected to each other. The first insulating section 122 is arranged on the top surface 113 of the battery housing body 110. The second insulating section 123 encloses the side surface 112 of the battery housing body 110 adjacent to the base surface 111. By assembling the insulating element 120 in two insulating sections, assembly efficiency can be increased, and the insulating effect on the exposed surfaces of the battery housing body 110 can be improved, thereby increasing the overall insulating performance of the battery 100.
[0067] Optionally, the first insulating section 122 includes an insulating protective film and / or an insulating protective coating. This embodiment contains no such limitation. The second insulating section 123 includes an insulating protective film and / or an insulating protective coating. The materials for the insulating protective film and the insulating protective coating have already been listed above and are not discussed again here.
[0068] In an optional embodiment, the first insulating section 122 and the second insulating section 123 can be made of the same material or of different materials. This embodiment does not contain any such limitation.
[0069] It should be noted that in this embodiment, the second insulating section 123 also covers at least part of the base area 111 of the battery housing body 110, i.e., the notch 121 is located on the second insulating section 123.
[0070] In this embodiment, the first insulating section 122 and the second insulating section 123 may or may not overlap on the top surface 113 of the battery housing body 110. Both cases are explained in detail in this embodiment.
[0071] The first insulating section 122 and the second insulating section 123 are arranged relative to each other on the top surface 113 of the battery housing body 110 such that the first insulating section 122 does not completely enclose the top surface 113 of the battery housing body 110, leaving an exposed section, and the second insulating section 123 is at least partially located on the top surface 113 of the battery housing body 110. The edge of the first insulating section 122 abuts the edge of the second insulating section 123 on the top surface 113 of the battery housing body 110, with the first insulating section 122 and the second insulating section 123 cooperating to enclose the top surface 113 of the battery housing body 110.In this way, the first insulating section 122 and the second insulating section 123 on the top surface 113 of the battery housing body 110 do not have an overlapping area, so that the arrangement of the insulating element 120 does not affect the thermal conductivity of the top surface 113 of the battery housing body 110 and the height of the battery 100 is not increased by an overlap of the first insulating section 122 with the second insulating section 123, thus ensuring the energy density of the battery pack.
[0072] Another arrangement of the first insulating section 122 and the second insulating section 123 on the top surface 113 of the battery housing body 110 is as follows: the second insulating section 123 is at least partially located on the top surface 113 of the battery housing body 110, and the first insulating section 122 overlaps the second insulating section 123 at least partially. In this way, the overlapping area between the first insulating section 122 and the second insulating section 123 can improve the insulating performance of the insulating element 120, thus giving the battery 100 a high insulating effect.
[0073] It should be noted that the total surface area S2 of the battery housing body 110, enclosed by the insulating element 120, assuming that the area of the first insulating section 122 is designated S3, the area of the second insulating section 123 is designated S4, and the overlapping area of the first insulating section 122 and the second insulating section 123 on the top surface 113 of the battery housing body 110 is designated S5, satisfies the relationship S2 = S3 + S4 - S5. It is evident from this that the size of a reflects the size of the battery housing body 110.
[0074] In this embodiment, to improve the insulating effect of the insulating element 120 at the connection point between the top surface 113 of the battery housing body 110 and the side surface 112 of the battery housing body 110, the proportion of the area of the top surface 113 of the battery housing body 110 enclosed by the first insulating section 122 to the total area of the top surface 113 of the battery housing body 110 is, for example, in the range of 30% to 95%. In this way, the area of the section where the first insulating section 122 is bent towards the top surface 113 of the battery housing body 110 can be limited so that the insulating performance of the insulating element 120 at the connection point between the top surface 113 of the battery housing body 110 and the side surface 112 of the battery housing body 110 is ensured.
[0075] It should be noted that the proportion of the area of the cover surface 113 of the battery housing body 110 enclosed by the first insulating section 122, relative to the total area of the cover surface 113 of the battery housing body 110, can be any value between 30% and 95%, or a range between any two values. This embodiment contains no such limitation. For example, the proportion of the area of the cover surface 113 of the battery housing body 110 enclosed by the first insulating section 122, relative to the total area of the cover surface 113 of the battery housing body 110, may be 30%, 45%, 50%, 60%, 70%, 80%, 90%, 95%, etc.
[0076] In one embodiment, the second insulating section 123 is an insulating film, the thickness of which is in the range of 80 µm to 110 µm. If the thickness of the insulating film is within this range, the insulating effect of the second insulating section 123 is good without increasing the height of the battery 100. The thickness of the insulating film must not be too great, as this would lead to excessive height of the battery 100 without any significant improvement in insulation performance. Likewise, the thickness of the insulating film must not be too small, as this could impair the insulating effect and lead to insulation failure. The thickness of the insulating film can be any value between 80 µm and 110 µm or any range between any two values. This embodiment contains no such restriction. For example, the thickness of the insulating film is 80 µm, 90 µm, 100 µm, 110 µm, etc.
[0077] In other embodiments, the second insulating section 123 can also be an insulating coating instead of an insulating film; that is, the second insulating section 123 is an insulating coating arranged on the top surface 113 of the battery housing body 110, with the thickness of the insulating coating being in the range of 130 µm to 170 µm. If the thickness of the insulating coating is within this range, the insulating effect of the second insulating section 123 is good without additionally increasing the height of the battery 100. The thickness of the insulating coating must not be too great, as this would lead to excessive height of the battery 100 without any significant improvement in insulation performance, and would also reduce the adhesion of the insulating coating, causing it to flake off easily. Likewise, the thickness of the insulating coating must not be too small, as this could impair the insulating effect and lead to insulation failure.The thickness of the insulating coating can be any value between 130 µm and 170 µm, or any range between any two values. This embodiment contains no such restriction. For example, the thickness of the insulating coating is 130 µm, 140 µm, 150 µm, 160 µm, or 170 µm.
[0078] Optionally, the adhesive layer 200 is located between the base surface 111 of the battery housing body 110 and the base plate 300, and the insulating element 120 overlaps at least partially with the adhesive layer 200. In this way, the adhesive layer 200 and the insulating element 120 overlap, so that the adhesive layer 200 is bonded not only to the part of the battery housing body 110 exposed by the notch 121, but also to the surface of the insulating element 120 facing the base plate 300. This results in a larger bonding area between the underside of the battery 100 and the adhesive layer 200, which increases the bond strength between the battery 100 and the base plate 300.
[0079] In an optional embodiment, the thickness of the adhesive layer 200 ranges from 0.5 mm to 3.4 mm. This improves the adhesive strength between the battery 100 and the base plate 300, provided the thickness of the adhesive layer 200 remains within a certain range. Since the adhesive layer 200 also has an insulating effect, the insulating performance between the battery 100 and the base plate 300 is simultaneously increased to some extent.
[0080] It should be noted that the thickness of the adhesive layer 200 can be any value between 0.5 mm and 3.4 mm, or a range between any two values. This embodiment contains no such restriction. For example, the thickness of the adhesive layer 200 may be 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.4 mm, etc.
[0081] For example, the dielectric constant of the adhesive layer 200 is in the range of 2.4 F / m to 4.2 F / m. It should be noted that the dielectric constant of the adhesive layer 200 mentioned in this embodiment was measured at a frequency of 1 MHz and lies within the range of 2.4 F / m to 4.2 F / m. If the dielectric constant of the adhesive layer 200 is within a certain range, the adhesive layer 200 thus possesses a certain insulating capacity, thereby improving the insulating performance between the battery 100 and the base plate 300.
[0082] It should be noted that the dielectric constant of the adhesive layer 200 can assume any value between 2.4 F / m and 4.2 F / m, or a range between any two values. This embodiment contains no such restriction. For example, the dielectric constant of the adhesive layer 200 is 2.4 F / m, 3 F / m, 3.2 F / m, 3.4 F / m, 3.8 F / m, 4 F / m, 4.2 F / m, etc.
[0083] Optionally, the thickness of the insulating layer 400 is in the range of 0.02 mm to 0.3 mm. Thus, if the thickness of the insulating layer 400 is within a certain range, it exhibits excellent insulating properties, thereby ensuring the insulating effect between the battery 100 and the base plate 300.
[0084] It should be noted that the thickness of the insulating layer 400 can be any value between 0.02 mm and 0.3 mm, or a range between any two values. This embodiment contains no such restriction. For example, the thickness of the insulating layer 400 is 0.02 mm, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, etc.
[0085] Optionally, in this embodiment, the base plate 300 can be a heat exchanger plate or an ordinary plate. This embodiment contains no restriction in this regard. If the base plate 300 is a heat exchanger plate, a and h satisfy the following relationship: 0.05 ≤ a / h ≤ 0.13. When the base plate 300 serves as a heat exchanger plate, the cooling effect for the battery can thus be improved. If the value of a / h is in the range of 0.05 to 0.13, not only is the connection strength between the battery 100 and the base plate 300 ensured and the insulation performance between the battery 100 and the base plate 300 improved, but the heat dissipation of the battery 100 is also optimized and the risk of thermal runaway of the battery 100 is reduced.
[0086] In one embodiment, the roughness Ra of the base plate 300 is in the range of 0.8 µm to 3.2 µm. Thus, the adhesion between the base plate 300 and the insulating layer 400 is good when the roughness of the base plate 300 is within a certain range. The insulating layer 400 adheres better to the base plate 300, thereby reducing the risk of detachment. As a result, the insulating layer 400 has fewer areas of weak insulation, which means that the bond strength between the base plate 300 and the battery housing body 110 is particularly high.
[0087] In one embodiment, the battery 100 also comprises an electrode column 140, wherein the electrode column 140 can be arranged on the side surface 112 or the base surface 111 of the battery housing body 110, while a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.10. If the electrode column 140 is located on the side surface 112 or the base surface 111 of the battery 100, electrical contact between the electrode column 140 and the base plate 300 must be prevented, i.e., a short circuit between the electrode column 140 and the base plate 300 must be prevented. If the value of a / h is in the range of 0.01 ≤ a / h ≤ 0.10, the insulation performance between the battery 100 and the base plate 300 can be ensured, thereby avoiding electrical contact between the electrode column 140 and the base plate 300 and improving the overall safety performance and insulation performance of the battery 100.
[0088] In other embodiments, if the battery includes an electrode column 140, the electrode column 140 can be arranged as shown in Fig. Figure 11 shows the electrode column 140 and the base plate 300, which are also located on the top surface 113 of the battery housing body 110. The top surface of the battery housing body 110 is arranged opposite the base surface 111 of the battery housing body 110, where a and h satisfy the following relationship: 0.03 ≤ a / h ≤ 0.13. Since the distance between the electrode column 140 and the base plate 300 is relatively large, a high bond strength between the battery 100 and the base plate 300 is achieved, provided that the value of a / h is in the range of 0.01 ≤ a / h ≤ 0.10.
[0089] For example, the value of the maximum distance d3 between the edge of the insulating layer 400 and the edge of the underside of the battery 100 projected orthogonally onto the insulating layer 400 is as shown in Fig. Figure 13 shows the thickness in the range of 0.5 mm to 7 mm. This improves the insulating effect at the notch 121 between the base plate 300 and the insulating element 120, ensuring that the insulating layer 400 completely covers the edge of the notch 121. Furthermore, while maintaining the insulating effect, the area of the insulating layer 400 does not need to be excessively large, thus reducing material loss and lowering the cost of the battery pack.
[0090] Optionally, the maximum distance d3 between the edge of the insulating layer 400 and the corresponding edge of the underside of the battery 100 projected orthogonally onto the insulating layer 400 can assume any value between 0.5 mm and 7 mm, or a range between any two values. This embodiment contains no such restriction. For example, the maximum distance d3 between the edge of the insulating layer 400 and the corresponding edge of the underside of the battery 100 projected orthogonally onto the insulating layer 400 may be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, etc.
[0091] It should be noted that the edge of the insulating layer 400 may project beyond the edge of the base 111 of the battery housing body 110, with the distance between the two satisfying the above-mentioned relationship, or that the edge of the insulating layer 400 may not project beyond the edge of the base 111 of the battery housing body 110, that is, the orthogonal projection of the base 111 of the battery housing body 110 onto the plane in which the insulating layer 400 is located completely covers the insulating layer 400 and the distance between the two corresponds to the above-mentioned relationship. This embodiment contains no such limitation.
[0092] Optionally, the battery pack typically comprises several batteries 100, the multiple batteries 100 being arranged in rows and / or columns spaced apart from one another on the base plate 300. In this embodiment, the insulating layer 400 covers at least the entire base area 111 of a battery 100. In this way, the insulating layer 400 completely covers the underside of the battery 100 and thus fulfills the requirements for the insulation of the underside of this battery 100. In some optional embodiments, the insulating layer 400 completely covers the underside of each battery 100 and thus fulfills the requirements for the insulation of the underside of the multiple batteries 100.
[0093] In some optional embodiments, the surface of the base plate 300 facing the battery 100 can completely cover the insulating layer 400, so that the underside of each battery 100 is covered by the insulating layer 400, which improves the insulating effect between the battery 100 and the base plate 300.
[0094] In further optional embodiments, several insulating layers 400 are arranged on the surface of the base plate 300 facing the battery 100, wherein the several insulating layers 400 each correspond to one of the several batteries 100 and each insulating layer 400 can cover the underside of the battery 100 corresponding to it.
[0095] When several batteries 100 are spaced apart on the base plate 300, the insulating layer 400 completely covers the underside of each battery 100, while the insulating layer 400 at least partially covers the underside of adjacent batteries 100. In this way, when the insulating layer 400 covers the underside of several batteries 100, the coating efficiency and the insulating effect of the insulating layer 400 are improved, which in turn increases the grouping effect of the batteries 100.
[0096] The battery pack presented in this embodiment has a notch 121 on the surface of the insulating element 120 of the battery 100, which faces the base plate 300. This notch increases the connection strength between the battery 100 and the base plate 300 and also improves the thermal conductivity of the battery 100. The insulating effect between the battery 100 and the base plate 300 can be ensured by adjusting the ratio between the area S1 of the notch 121 and the total area S2 of the surface of the battery housing body 110, which is enclosed by the insulating element 120, as well as the minimum distance h between the battery housing body 110 at the notch 121 and the base plate 300. Furthermore, the battery pack also exhibits a relatively high energy density.
[0097] This embodiment also provides a method for testing the insulation performance, which can be used to test the insulation performance between the battery and the base plate.
[0098] During the test, various a / h values were specified, and the resistance between the battery and the base plate 300 was measured at these different a / h values. Cases where the a / h value was in the range of 0.01 to 0.13 were designated as exemplary embodiments. Twenty-three such embodiments were described in this exemplary embodiment. Cases where the a / h value was outside the range of 0.01 to 0.13 were designated as comparative examples. Four comparative examples were described in this exemplary embodiment. For each exemplary embodiment and each comparative example, ten batteries of the same type were used, differing only in their a / h values, while all other properties were identical. A notch 121 was formed on the surface of the insulating element 120 of the battery 100, and the notch 121 was subsequently cleaned with alcohol.After natural drying, adhesive was applied to the surface of the battery housing body 110 facing the base plate (specifically at the location of the notch), creating an adhesive layer 200. The adhesive-coated battery was then bonded to the aluminum sheet (serving as the base plate 300) coated with an insulating layer 400 and cured at 25 °C for 24 hours. In the various embodiments and comparative examples, the ratio a between the area S1 of the notch 121 of the insulating element 120 and the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120, as well as the minimum distance h of the battery housing body 110 at the notch 121 to the aluminum sheet, were as shown in Table 1 below. All other features were identical. The resistance between the battery 100 and the aluminum sheet was measured using an insulation resistance meter.For this purpose, one output of the insulation resistance meter was connected to the aluminum sheet and the other to the aluminum vent on the battery surface. A DC voltage of 3000 V was then applied between the two terminals, the current was measured, and the resistance between battery 100 and the aluminum sheet was calculated using formula (1). The test results were determined by calculating the average of the resistance measurements of the 10 batteries in each embodiment or comparison example. The specific results are listed in Table 1. If the measured resistance is greater than or equal to 500 MΩ, the insulation between battery 100 and the aluminum sheet is considered satisfactory; if the measured resistance is less than 500 MΩ, the insulation between battery 100 and the aluminum sheet is considered unsatisfactory. R=U / I
[0099] This embodiment also provides a method for measuring the pull-out force, which can be used to test the pull-out force between the battery and the base plate.
[0100] Similarly, for the various embodiments and comparative examples, 10 batteries of the same type were selected, differing only in their a / h values, while all other properties were identical. A notch 121 was formed on the surface of the insulating element 120 of the battery 100, and the notch 121 was subsequently cleaned with alcohol. After natural drying, adhesive was applied to the surface of the battery housing 110 facing the base plate (specifically at the location of the notch), creating an adhesive layer 200. The adhesive-coated battery was then glued to the aluminum sheet (serving as the base plate 300) coated with an insulating layer 400 and cured at 25 °C for 24 hours.In the various embodiments and comparative examples, the ratio a between the area S1 of the notch 121 of the insulating element 120 and the total area S2 of the surface of the battery housing body 110 enclosed by the insulating element 120, as well as the minimum distance h of the battery housing body 110 at the notch 121 to the aluminum sheet, are as shown in Table 1 below. All other features were identical. The pull-out force of the battery 100 from the aluminum sheet was measured using an electronic universal testing machine (ETM304C from Wanze Shenzhen) at a speed of 5 mm / min. Ten tests were performed for each embodiment or comparative example, and the average values were determined. The specific results are listed in Table 1. If the measured pull-out force is at least 10 MPa, the bond strength between the battery and the aluminum sheet is considered to be sufficient.If the measured pull-off force is less than 10 MPa, the bond strength between the battery and the aluminum sheet is considered to have failed. Table 1 a0.01 to 0.2 h0.7 to 3.8 uh Insulation test (in MΩ) Tensile strength (in MPa) Example 1 0,011 0,73 0,015 573 12,1 Example 2 0,012 1,22 0,010 582 13,2 Example 3 0,043 1,54 0,028 588 15,6 Example 4 0,062 2,12 0,029 582 16,2 Example 5 0,086 2,53 0,034 586 17,1 Example 6 0,106 2,78 0,038 593 17,9 Example 7 0,127 3,22 0,039 599 18,6 Example 8 0,153 3,47 0,044 602 19,2 Example 9 0,176 3,64 0,048 613 20,3 Example 10 0,198 3,72 0,053 602 20,4 Example 11 0,162 2,12 0,076 612 22,9 Example 12 0,177 1,88 0,094 586 23,5 Example 13 0,189 1,69 0,112 576 22,4 Example 14 0,191 1,48 0,129 569 23,9 Example 15 0,008 0,74 0,011 603 11,9 Example 16 0,007 0,71 0,010 610 11,2 Example 17 0,213 2,75 0,077 533 20,8 Example 18 0,211 3,34 0,063 524 18,3 Example 19 0,044 0,59 0,075 520 18,5 Example 20 0,062 0,61 0,102 532 17,3 Example 21 0,182 3,95 0,046 612 11,3 Example 22 0,194 3,92 0,049 609 12,4 Example 23 0,241 3,91 0,062 596 12,8 Comparative example 1 0,2 1,23 0,163 482 16,2 Comparative example 2 0,01 1,83 0,005 642 8,9 Comparative example 3 0,35 1,95 0,179 477 15,8 Comparative example 4 0,043 6,23 0,007 698 7,8
[0101] A comparison of the experimental data from embodiments 1 to 14 and comparative examples 1 to 4 shows that the adhesion between the battery 100 and the aluminum sheet is good when the value of a / h is within a suitable range, and that the insulating performance between the two is good, so there is no risk of a short circuit. A comparison of the experimental data from embodiments 1 to 14 with those from embodiments 15 to 23 shows that if a is too small, the insulating element 120 covers too large a proportion of the surface of the battery housing body 110, resulting in poor heat dissipation from the battery. If a is too large, heat transfer between adjacent batteries 100 occurs more rapidly, so that in the event of thermal runaway of a battery 100, the heat transfer between adjacent batteries 100 cannot be effectively reduced.If h is too small, the heat exchange rate between battery 100 and the base plate 300 is too high, so that thermal runaway in one battery 100 will affect other batteries 100. If h is too large, heat dissipation at the bottom of battery 100 is insufficient.
[0102] It should be noted that these are merely preferred embodiments of the present invention and the technical principles applied therein. Those skilled in the art will recognize that the present invention is not limited to the specific embodiments described herein, but that various obvious modifications, adaptations, and substitutions are possible without departing from the scope of protection of the present invention. Although the present invention has been explained in considerable detail with reference to the foregoing embodiments, it is not limited to them, but can also include further equivalent embodiments without deviating from the fundamental concept of the present invention, the scope of which is determined by the wording of the appended claims.
[0103] The present invention belongs to the technical field of batteries and discloses a battery pack comprising a battery, an adhesive layer, and a base plate, wherein the adhesive layer is located between the battery and the base plate. The battery comprises a battery housing body and an insulating element that surrounds the surface of the battery housing body. The insulating element has a notch, the notch causing a base surface of the battery housing body to be at least partially exposed on the side facing the base plate. The adhesive layer is arranged at least partially at the notch and bonded to the base plate. An insulating layer is arranged between the base plate and the adhesive layer. The orthogonal projection of the notch onto the base plate coincides with the orthogonal projection of the insulating layer onto the base plate.The ratio between the area S1 of the notch in the insulating element and the total area S2 of the surface of the battery housing body enclosed by the insulating element is denoted as a, i.e., a = S1 / S2. The minimum distance of the battery housing body at the location of the notch to the base plate is h mm, where a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.13. The battery pack provided by the present invention is characterized by high insulation performance, high adhesion between the battery and the base plate, and high energy density.
Claims
Battery pack comprising a battery (100), an adhesive layer (200) and a base plate (300), wherein the base plate (300) serves to support the battery (100), the adhesive layer (200) is located between the battery (100) and the base plate (300) and serves to firmly connect the base plate (300) to the battery (100), characterized in that the battery comprises a battery housing body (110) and an insulating element (120) that encloses the surface of the battery housing body (110), wherein the insulating element (120) has a notch (121), wherein the notch (121) causes a base surface of the battery housing body (110) to be at least partially exposed on the side facing the base plate (300), wherein the adhesive layer (200) is arranged at least partially at the notch (121) and is bonded to the base plate (300), wherein between an insulating layer (400) is arranged between the base plate (300) and the adhesive layer (200),wherein an orthogonal projection of the notch (121) onto the base plate (300) coincides with an orthogonal projection of the insulating layer (400) onto the base plate (300); wherein a ratio between an area S1 of the notch (121) of the insulating element (120) and a total area S2 of the surface of the battery housing body (110) enclosed by the insulating element (120) is denoted as a, i.e., a = S1 / S2, wherein the minimum distance of the battery housing body (110) located at the notch (121) to the base plate (300) is h mm, and a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.13; wherein the area of the orthogonal projection of the notch (121) onto the base plate (300) corresponds to an area of the base surface of the battery housing body (110), and the value of h is in the range of 0.7 up to 3.
8. Battery pack according to claim 1, characterized in that a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.
1. Battery pack according to claim 1, characterized in that the battery (100) further comprises an explosion protection valve (130), wherein the explosion protection valve (130) is arranged on the battery housing body (110), wherein the surface of the battery housing body (110) on which the explosion protection valve (130) is arranged differs from the surface of the battery housing body (110) opposite the notch (121). Battery pack according to claim 1, characterized in that the insulating element (120) encloses a side surface of the battery housing body (110) adjacent to the base surface of the battery housing body (110) and that there is a distance between the insulating element (120) and the base surface of the battery housing body (110), wherein the ratio of the length d1 of the distance in the vertical direction of the battery housing body (110) to the height d2 of the battery housing body (110) is in the range of 0.05 to 0.95 and a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.
06. Battery pack according to claim 1, characterized in that the insulating element (120) has an opening (124) on the side of the battery housing body (110) facing away from the base plate (300) in the area of the top surface, wherein a and h satisfy the following relationship: 0.03 ≤ a / h ≤ 0.
13. Battery pack according to claim 1, characterized in that the insulating element (120) comprises a first insulating section (122) and a second insulating section (123), wherein the first insulating section (122) is arranged on the top surface of the battery housing body (110) on the side facing away from the base plate (300), wherein the second insulating section (123) encloses the side surface of the battery housing body (110) adjacent to the base surface, wherein the notch (121) is arranged on the second insulating section (123). Battery pack according to claim 1, characterized in that the adhesive layer (200) is located between the base surface of the battery housing body (110) and the base plate (300) and that the insulating element (120) overlaps at least partially with the adhesive layer (200). Battery pack according to claim 1, characterized in that the thickness of the adhesive layer (200) is in the range of 0.5 mm to 3.4 mm. Battery pack according to claim 1, characterized in that the thickness of the insulating layer (400) is in the range of 0.02 mm to 0.3 mm. Battery pack according to claim 1, characterized in that a is in the range of 0.01 to 0.
2. Battery pack according to claim 1, characterized in that the battery (100) further comprises an electrode column, wherein the electrode column is located on the side surface or base surface of the battery housing body (110) and a and h satisfy the following relationship: 0.01 ≤ a / h ≤ 0.
10. Battery pack according to claim 1, characterized in that the battery (100) further comprises an electrode column, wherein the electrode column is located on the top surface of the battery housing body (110), wherein the top surface of the battery housing body (110) is opposite the base surface of the battery housing body (110) and a and h satisfy the following relationship: 0.03 ≤ a / h ≤ 0.13.