Cylindrical battery module heating film structure and cylindrical battery module

Abstract

The utility model provides a kind of cylindrical battery module heating film structure and cylindrical battery module, it is related to battery technical field, heating film structure includes multiple array arrangement's heating film unit, heating film unit includes first membrane body, second membrane body and heating wire: first membrane body is semicircular structure, for adhering cylindrical battery outer side face;Second membrane body is circular structure, with first membrane body axial connection and for adhering cylindrical battery end face;Heating wire is set in first membrane body and second membrane body, and the heating wire in multiple heating film units is electrically connected in series. Through the modularization heating film unit design, semicircular side heating film and circular end face heating film are combined, the large-area uniform heating to cylindrical battery outer surface is realized, and the structure significantly improves heating efficiency. Semicircular and circular membrane body structure naturally adhere cylindrical battery surface, simplify installation process, avoid the gap between traditional serpentine heating film and cylindrical battery, thereby avoid the emergence of dry burning situation.

Description

Technical Field

[0001] This utility model relates to the field of cylindrical battery technology, and in particular to a heating film structure for a cylindrical battery module and a cylindrical battery module. Background Technology

[0002] Cylindrical batteries are widely used in electric vehicles, energy storage systems, and other fields due to their advantages such as high production efficiency, low production cost, and good product consistency. However, in low-temperature environments, the charge and discharge performance of batteries will significantly decrease, and may even lead to safety hazards due to problems such as lithium deposition. Therefore, heating the battery module to maintain a suitable operating temperature is crucial.

[0003] Currently, cylindrical battery modules typically use flexible heating films for heating, but existing heating film structures (such as serpentine heating films) have certain limitations. First, the limited contact area between the serpentine heating film and the cylindrical battery results in low heating efficiency, making it difficult to meet the demand for rapid temperature rise. Second, due to the gaps between the cylindrical batteries, the heating film lacks effective heat dissipation at these gaps, easily leading to localized overheating and dry burning, which not only affects the lifespan of the heating film but may also pose safety hazards. Furthermore, the fixing and assembly of flexible heating films within modules is complex, especially for multi-layered stacked battery modules, where misalignment or loosening during installation can easily occur, impacting production efficiency. Utility Model Content

[0004] In view of this, this utility model proposes a heating film structure for a cylindrical battery module and a cylindrical battery module to solve the problems of insufficient contact area between the existing heating film and the cylindrical battery, difficult installation, and easy dry burning at the battery gap.

[0005] The technical solution of this utility model is implemented as follows:

[0006] On one hand, this utility model provides a heating film structure for a cylindrical battery module, comprising multiple heating film units arranged in an array, wherein the heating film unit includes:

[0007] The first membrane, with a semi-circular structure, is used to adhere to the outer surface of the cylindrical battery.

[0008] The second membrane has a circular structure and is axially connected to the first membrane and is used to adhere to the end face of the cylindrical battery.

[0009] A heating wire is disposed in the first membrane body and the second membrane body;

[0010] The heating wires in multiple heating film units are electrically connected in series.

[0011] Based on the above technical solution, preferably, the heating wire in each heating film unit includes a first heating section and a second heating section connected in series. The first heating section is arranged in a serpentine pattern along the axial direction in the first film body, and the second heating section is arranged in a circular circumferential pattern in the second film body.

[0012] Based on the above technical solution, preferably, the second heating section has an initial end and an end end, the initial end is connected in series with the end end of the first heating section, the end end extends to the edge of the second membrane to form a current output end, and the initial end of the first heating section extends to the edge of the second membrane to form a current input end.

[0013] Based on the above technical solution, preferably, a conductive connection is provided between adjacent heating film units, which electrically connects the end of the second heating section in the upstream unit to the beginning of the first heating section in the downstream unit.

[0014] Based on the above technical solution, preferably, it also includes a first electrode connection end and a second electrode connection end, wherein the first electrode connection end is connected to the beginning end of the first heating segment in the first heating film unit, and the second electrode connection end is connected to the end end of the second heating segment in the last heating film unit.

[0015] Based on the above technical solution, preferably, both the first membrane and the second membrane are flexible insulating membrane materials with a thickness of 0.05-0.3 mm.

[0016] Based on the above technical solution, preferably, a pressure-sensitive adhesive layer is provided on the inner surface of both the first membrane and the second membrane, and a release film is provided on the pressure-sensitive adhesive layer.

[0017] Secondly, this utility model also discloses a cylindrical battery module, including a module bracket, multiple cylindrical batteries, and the cylindrical battery module heating film structure described in the first aspect. The module bracket is provided with multiple mounting slots. The second film of the heating film unit is horizontally disposed on the bottom surface of the mounting slot. At least a portion of the first film is located in the mounting slot. The cylindrical batteries are vertically disposed in the mounting slot, and the outer surface of the cylindrical batteries is connected to the first film, and the bottom surface of the cylindrical batteries is connected to the second film.

[0018] Based on the above technical solution, preferably, the second membrane has a through hole for the cylindrical battery terminal to pass through, and the bottom surface of the module bracket has a mounting hole that communicates with the mounting groove for the terminal to pass through.

[0019] The present invention has the following advantages over the prior art:

[0020] (1) By combining a semi-circular side heating film and a circular end heating film through a modular heating film unit design, large-area uniform heating of the outer surface of the cylindrical battery is achieved. This structure significantly improves heating efficiency, avoids the problem of insufficient contact area of ​​traditional serpentine heating films, and simplifies the installation process. In addition, the semi-circular and circular film structures naturally fit the surface of the cylindrical battery, avoiding the gap between the traditional serpentine heating film and the cylindrical battery, thereby avoiding dry burning and improving heat conduction efficiency.

[0021] (2) By dividing the heating wire into a first heating section arranged in an axial serpentine pattern and a second heating section arranged in a circumferential pattern, precise heating of the sides and ends of the cylindrical battery is achieved. The serpentine pattern improves the uniformity of side heating, while the circumferential pattern optimizes the heat distribution on the ends. The series connection method ensures the consistency of heating power and simplifies circuit design.

[0022] (3) By connecting the first heating section and the second heating section in series and centrally setting all electrical interfaces at the edge of the second membrane, more efficient current transmission and more convenient installation and maintenance are achieved. This design not only ensures the thermal performance of the heating membrane, but also improves the reliability and manufacturability of the product.

[0023] (4) By integrating the heating film unit into each battery mounting slot, independent thermal management of individual batteries is achieved. Each battery can obtain a uniform and controllable heating effect, avoiding temperature differences between batteries within the module. At the same time, compared with traditional battery modules with serpentine heating films, the battery module with integrated heating film structure in this embodiment allows the heating film unit to be in close contact with the surface of the cylindrical battery, greatly improving the heating efficiency of the cylindrical battery. In addition, there is no gap between the heating film unit and the cylindrical battery, which can avoid dry burning and improve heat conduction efficiency. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a three-dimensional structural diagram of the cylindrical battery module heating film structure disclosed in this utility model.

[0026] Figure 2 This is a schematic diagram of the heating film structure and cylindrical battery assembly structure of the cylindrical battery module disclosed in this utility model.

[0027] Figure 3This is a series path diagram of the heating film unit disclosed in this utility model;

[0028] Figure 4 This is a schematic diagram of the overall structure of the cylindrical battery module disclosed in this utility model;

[0029] Figure 5 This is a first-view perspective three-dimensional structural diagram of the cylindrical battery module disclosed in this utility model.

[0030] Figure 6 This is a second-view perspective three-dimensional structural diagram of the cylindrical battery module disclosed in this utility model;

[0031] Figure label:

[0032] 1. Heating film unit; 11. First film body; 12. Second film body; 120. Through hole; 13. Heating wire; 131. First heating section; 132. Second heating section; 2. Conductive connection part; 3. First electrode connection end; 4. Second electrode connection end; 5. Module bracket; 6. Cylindrical battery; 51. Mounting groove; 52. Mounting hole. Detailed Implementation

[0033] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0034] like Figure 1 As shown, combined with Figure 2-3 This utility model discloses a cylindrical electric module heating film structure, which includes multiple arrayed heating film units 1. The multiple heating film units 1 are arrayed on the same horizontal plane, and their array arrangement is consistent with the arrangement of multiple cylindrical batteries 6 in a group.

[0035] Each heating film unit 1 comprises two key parts: a first film 11 and a second film 12. The first film 11 is designed as a semi-circular structure, specifically for adhering to the outer surface of the cylindrical battery 6; the second film 12 is a circular structure, axially connected to the first film 11, for adhering to the end face of the cylindrical battery 6. Heating wires 13 are embedded within these two films, serving as the heating element. The heating wires 13 of multiple heating film units 1 are connected in series to form a complete heating circuit.

[0036] In this embodiment, the semi-circular structure of the first film 11 allows it to closely conform to the arc-shaped outer surface of the cylindrical battery 6, significantly increasing the contact area. The circular structure of the second film 12 matches the shape of the battery end face, ensuring uniform heating of the end face. This combined design overcomes the limitation of traditional serpentine heating films that can only cover part of the battery surface, achieving all-round wrapping of the outer side and end face of the cylindrical battery 6.

[0037] The heating wire 13, serving as the heat source, is integrated inside the first membrane 11 and the second membrane 12. This built-in design avoids the short-circuit risk that may arise from exposed heating wire 13, while ensuring efficient heat conduction. The heating wires 13 of multiple heating membrane units 1 are connected in series, allowing the entire heating system to be controlled by a single circuit, simplifying the power supply design.

[0038] The array arrangement of the heating film unit 1 allows it to flexibly adapt to cylindrical battery modules of different specifications. Each heating film unit 1 corresponds independently to one cylindrical battery 6. During installation, it is only necessary to wrap the side of the cylindrical battery 6 with the first film 11 and attach the second film 12 to the end face of the cylindrical battery 6. This modular installation method greatly reduces the assembly complexity.

[0039] By combining a semi-circular side heating film and a circular end heating film through a modular heating film unit 1, large-area uniform heating of the outer surface of the cylindrical battery 6 is achieved. This structure significantly improves heating efficiency, avoids the problem of insufficient contact area in traditional serpentine heating films, and simplifies the installation process. In addition, the semi-circular and circular film structures naturally conform to the surface of the cylindrical battery 6, avoiding gaps between the traditional serpentine heating film and the cylindrical battery 6, thus preventing dry burning and improving heat conduction efficiency.

[0040] As one implementation method, this embodiment provides a specific arrangement of the heating wire 13. Specifically, the heating wire 13 in each heating film unit 1 is divided into two functional segments: a first heating segment 131 and a second heating segment 132, which are connected in series. This segmented design allows the heating wire 13 to be optimally arranged for different parts of the battery (sides and ends), thereby improving heating uniformity and heat conduction efficiency.

[0041] The first heating section 131 is disposed within the first membrane 11 and arranged in a serpentine pattern along the axial direction. The serpentine arrangement is characterized by the heating wires 13 repeatedly folding back and forth along the length of the membrane, forming a continuous heating path. This arrangement ensures that heat is evenly distributed along the side of the battery, avoiding localized overheating or cold spots. Simultaneously, the axial arrangement maximizes the contact area between the heating wires 13 and the battery, improving heat exchange efficiency.

[0042] The second heating section 132 is disposed within the second film 12 and arranged circumferentially. This circumferential arrangement ensures that the heating wire 13 surrounds the end face of the battery, guaranteeing uniform heating of the cylindrical battery 6 end face. Traditional serpentine heating films can only cover a portion of the side surface of the cylindrical battery 6 and cannot heat the end face of the cylindrical battery 6. However, in this embodiment, the first heating section 131 and the second heating section 132 are a continuous heating wire 13, which can heat both the side surface and the bottom surface of the cylindrical battery 6, greatly improving the heating efficiency of the cylindrical battery 6.

[0043] The first heating section 131 and the second heating section 132 are connected in series, so that the current flows through the two heating sections sequentially. This connection method ensures that the power of the two heating sections is consistent and avoids the problem of uneven current distribution caused by parallel connection. At the same time, the series design simplifies the circuit structure and facilitates the cascading of multiple heating film units 1 to form a complete heating system.

[0044] By dividing the heating wire 13 into a first heating section 131 arranged in an axial serpentine pattern and a second heating section 132 arranged in a circumferential pattern, precise heating of the sides and ends of the cylindrical battery 6 is achieved. The serpentine arrangement improves the uniformity of side heating, while the circumferential arrangement optimizes the heat distribution on the end face. The series connection ensures the consistency of heating power and simplifies circuit design. Overall, this solution further improves the thermal management performance of the heating film, enabling the battery module to heat up quickly and uniformly in low-temperature environments, while avoiding problems such as localized overheating or uneven heating.

[0045] This embodiment further specifies the electrical connection method of the heating wire 13. Specifically, the second heating section 132 has an initial end and an end end. The initial end is connected in series with the end of the first heating section 131. The end end extends to the edge of the second membrane 12 to form a current output end, and the initial end of the first heating section 131 extends to the edge of the second membrane 12 to form a current input end.

[0046] By directly connecting the initial end of the second heating section 132 in series with the terminal of the first heating section 131, a continuous current path is formed. This design ensures that the heating current can flow sequentially through the first heating section 131 and the second heating section 132, enabling the two heating sections to work together to complete the heating function of the battery.

[0047] The beginning of the first heating section 131 and the end of the second heating section 132 both extend to the edge region of the second membrane 12. The advantage of this layout is that all electrical connection points are concentrated at the edge of the second membrane 12, which facilitates unified wiring operations. In particular, when making electrical series connections between heating membrane units 1, electrical connections can be completed by simply making unified wiring in the edge region. When maintenance is required, problems at the connection points can be quickly located and handled without disassembling the entire heating membrane structure.

[0048] By connecting the first heating section 131 and the second heating section 132 in series and centralizing all electrical interfaces at the edge of the second membrane 12, more efficient current transmission and easier installation and maintenance are achieved. This design ensures the thermal performance of the heating membrane while improving the reliability and manufacturability of the product.

[0049] This embodiment further proposes an electrical connection method between multiple heating film units 1. Specifically, by setting a dedicated conductive connection part 2 between adjacent heating film units 1, the end of the second heating section 132 of the upstream unit is electrically connected to the beginning of the first heating section 131 of the downstream unit. This design realizes the modular series connection of the heating film units 1, enabling multiple independent units to form a complete heating system.

[0050] The conductive connection 2 ensures that the current flows sequentially through each heating film unit 1 along a predetermined path. The current from the upstream unit after heating is completed is directly transmitted to the downstream unit via the conductive connection 2, forming a continuous and stable current loop. This series connection ensures power consistency across all heating film units 1 and avoids the uneven current distribution problems that might occur with parallel connections.

[0051] In this embodiment, the conductive connection portion 2 can be a flexible circuit board, through which the end of the second heating section 132 of the upstream unit is welded to the beginning of the first heating section 131 of the downstream unit. Due to the thin and light structure of the flexible circuit board, it is integrated between adjacent heating film units 1 without occupying additional space, maintaining the compactness of the overall structure. This design achieves electrical connection without affecting the fit between the heating film unit 1 and the battery, ensuring that the heat conduction efficiency is not affected.

[0052] In some implementations, in order to power the entire heating film structure, the heating film structure of this embodiment also includes a first electrode connection end 3 and a second electrode connection end 4. The two connection ends are located at the beginning and end of the entire heating film system, respectively. The first electrode connection end 3 is connected to the beginning of the first heating section 131 of the first heating film unit 1, and the second electrode connection end 4 is connected to the end of the second heating section 132 of the last heating film unit 1. This structure provides a standardized power access point for the entire heating system.

[0053] By setting up dedicated electrode connection terminals, the current loop of the entire heating film system is ensured to be complete and closed. Current enters from the first electrode connection terminal 3, flows sequentially through all the series-connected heating film units 1, and exits from the second electrode connection terminal 4, forming a complete heating loop. This design avoids the poor contact problems that may occur with traditional distributed wiring methods, thus improving system reliability.

[0054] In this embodiment, the electrode connection end consists of a flexible circuit board and terminals. The terminals are connected to both ends of the entire heating film system through the flexible circuit board. An external power supply is connected to the terminals, forming a complete circuit in the entire heating film system. The first electrode connection end 3 and the second electrode connection end 4 have opposite polarities. For example, if the first electrode connection end 3 is connected to the positive terminal of the power supply, then the second electrode connection end 4 is connected to the negative terminal of the power supply.

[0055] In some embodiments, both the first membrane 11 and the second membrane 12 are flexible insulating membrane materials with a thickness of 0.05-0.3 mm. By using a flexible insulating membrane material as the base material, this material selection allows the heating membrane to closely adhere to the irregular surface of the cylindrical battery 6. The flexibility of the membrane material ensures both flexibility during installation and structural stability during use. In some embodiments, the flexible insulating membrane material can be a PI film.

[0056] Within a thickness range of 0.05-0.3 mm, the membrane material achieves an optimal balance between thermal resistance and flexibility. Too thin a membrane may result in insufficient mechanical strength, while too thick a membrane will affect thermal conductivity.

[0057] As some embodiments, pressure-sensitive adhesive layers are provided on the inner surfaces of the first membrane 11 and the second membrane 12, and release films are provided on the pressure-sensitive adhesive layers.

[0058] The pressure-sensitive adhesive layer not only provides bonding but also optimizes thermal interface performance. The adhesive layer fills the microscopic gaps between the heating film and the battery surface, reducing contact thermal resistance. The release film covering the pressure-sensitive adhesive layer uses a specially treated anti-stick material with easy-to-peel properties. This protective film keeps the adhesive surface clean and tacky before installation and can be easily peeled off without leaving any adhesive residue. Installation is simple: just peel off the release film and press the heating film onto the battery surface to secure it, without the need for additional fasteners or tools. This "plug and play" installation method significantly simplifies the assembly process.

[0059] This utility model embodiment also discloses a cylindrical battery module, as shown in the attached drawing. Figure 4-6 As shown, it includes a module support 5, multiple cylindrical batteries 6, and the cylindrical battery module heating film structure.

[0060] The module bracket 5 serves as the main support, and has multiple precisely machined mounting slots 51 inside, each corresponding to a cylindrical battery unit 6. This modular design enables standardized integrated assembly of the battery and heating film, facilitating mass production.

[0061] The second film 12 of the heating film unit 1 is horizontally laid at the bottom of the mounting groove 51, forming full contact with the battery end face; the first film 11 is partially embedded in the mounting groove 51, closely fitting the side of the battery. This three-dimensional layout makes full use of every inch of space on the battery surface, maximizing the contact area between the heating film and the battery, and significantly improving the heat conduction efficiency.

[0062] By integrating the heating film unit 1 into each battery mounting slot 51, independent thermal management of individual batteries is achieved. Each battery can obtain a uniform and controllable heating effect, avoiding temperature differences between batteries within the module. Furthermore, compared to traditional battery modules with serpentine heating films, the battery module in this embodiment with the integrated heating film structure allows the heating film unit 1 to be in close contact with the surface of the cylindrical battery 6, significantly improving the heating efficiency of the cylindrical battery 6. Simultaneously, the absence of gaps between the heating film unit 1 and the cylindrical battery 6 prevents dry burning and improves heat conduction efficiency.

[0063] In some embodiments, the second membrane 12 has a through hole for the electrode post of the cylindrical battery 6 to pass through, and the bottom surface of the module bracket 5 has a mounting hole 52 that communicates with the mounting groove 51 for the electrode post to pass through.

[0064] With this configuration, for the cylindrical battery 6 with terminals at both ends, the top of the battery module can connect the terminals of the cylindrical battery 6 in series and parallel through several busbars. By setting multiple busbars on the bottom surface of the module bracket 5, the terminals of the cylindrical battery 6 that pass through the through hole and the mounting hole 52 at the bottom can be connected in series and parallel, thereby solving the electrical connection requirements of the top and bottom of the cylindrical battery 6. At the same time, the terminals passing through the through hole on the second membrane 12 and the mounting hole 52 on the module bracket 5 can realize the thermoelectric separation design of the cylindrical battery 6.

[0065] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cylindrical battery module heating film structure, characterized by, The heating film unit (1) comprises multiple heating film units arranged in an array, wherein the heating film unit (1) includes: The first membrane (11) has a semi-circular structure and is used to adhere to the outer side of the cylindrical battery (6); The second membrane (12) has a circular structure and is axially connected to the first membrane (11) and used to adhere to the end face of the cylindrical battery (6); Heating wires (13) are disposed in the first membrane body (11) and the second membrane body (12), and the heating wires in the multiple heating membrane units (1) are electrically connected in series.

2. The cylindrical battery module heating film structure of claim 1, wherein: The heating wire (13) in each heating film unit (1) includes a first heating section (131) and a second heating section (132) connected in series. The first heating section (131) is arranged in a serpentine pattern along its axial direction in the first film body (11), and the second heating section (132) is arranged in a circular circumferential pattern in the second film body (12).

3. The cylindrical battery module heating film structure of claim 2, wherein: The second heating section (132) has an initial end and an end end. The initial end is connected in series with the end end of the first heating section (131). The end end extends to the edge of the second membrane (12) to form a current output end, and the initial end of the first heating section (131) extends to the edge of the second membrane (12) to form a current input end.

4. The cylindrical battery module heating film structure of claim 3, wherein: A conductive connection (2) is provided between adjacent heating film units (1), which electrically connects the end of the second heating section (132) in the upstream unit to the beginning of the first heating section (131) in the downstream unit.

5. The cylindrical battery module heating film structure of claim 4, wherein: It also includes a first electrode connection end (3) and a second electrode connection end (4), wherein the first electrode connection end (3) is connected to the beginning of the first heating segment (131) in the first heating film unit (1), and the second electrode connection end (4) is connected to the end of the second heating segment (132) in the last heating film unit (1).

6. The cylindrical battery module heating film structure of claim 1, wherein: The first membrane (11) and the second membrane (12) are both flexible insulating membrane materials with a thickness of 0.05-0.3 mm.

7. The cylindrical battery module heating film structure of claim 6, wherein: The inner surfaces of the first membrane (11) and the second membrane (12) are provided with pressure-sensitive adhesive layers, and release films are provided on the pressure-sensitive adhesive layers.

8. A cylindrical battery module comprising a module holder (5), a plurality of cylindrical batteries (6) and a cylindrical battery module heating film structure according to any one of claims 1 to 7, characterized in that: The module bracket (5) is provided with multiple mounting slots (51). The second membrane (12) of the heating film unit (1) is horizontally disposed on the bottom surface of the mounting slot (51). At least a part of the first membrane (11) is located in the mounting slot (51). The cylindrical battery (6) is vertically disposed in the mounting slot (51), and the outer side of the cylindrical battery (6) is connected to the first membrane (11). The bottom surface of the cylindrical battery (6) is connected to the second membrane (12).

9. The cylindrical battery module of claim 8, wherein, The second membrane (12) has a through hole for the electrode post of the cylindrical battery (6) to pass through, and the bottom surface of the module bracket (5) has a mounting hole (52) that communicates with the mounting groove (51) for the electrode post to pass through.

Images