Electrical structure, battery modules and battery packs

Abstract

This utility model relates to the field of power battery technology, and more particularly to an electrical structure, battery module, and battery pack. The electrical structure includes: an integrated busbar; and a gas detection unit connected to and integrated into the integrated busbar, the gas detection unit including a sampling section. Beneficial effects include: the sampling section of the gas detection unit can detect sampled gases, which is beneficial for timely detection of cell leakage, enabling monitoring of the cell's condition and thus timely detection of battery failure, improving safety performance; based on this, the gas detection unit is connected to the integrated busbar, allowing the gas detection unit to be integrated onto the integrated busbar, resulting in high integration, easy modularization, simplified structure, and space saving, thereby achieving lightweight and convenient assembly of the overall structure.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to an electrical structure, battery module and battery pack. Background Technology

[0002] Batteries are widely used in the new energy vehicle field, especially cylindrical batteries, which have advantages such as good consistency, high production efficiency, and strong heat dissipation at the system level, giving them a significant advantage in electric vehicles and leading to their wider application. However, batteries sometimes experience moisture ingress. For example, cylindrical batteries are prone to moisture ingress due to poor sealing at the positive terminal and negative electrode casing seals. Additionally, the welding points in cylindrical battery packs are generally on the positive terminal and the negative electrode casing on the positive terminal side; poor welding leading to leaks can also cause moisture ingress. Moisture reacts with the electrolyte to produce hydrofluoric acid (HF), a highly corrosive acid that corrodes internal metal parts, the battery casing, and seals, causing battery ruptures and leaks. Furthermore, moisture can damage the solid electrolyte interphase (SEI) membrane inside the battery, increasing internal pressure and causing deformation of the positive terminal. This can lead to the leakage of hydrogen and other byproduct gases from the positive terminal side of cylindrical batteries.

[0003] In daily life and production processes, the primary method of determining whether a battery cell has experienced gas or liquid leakage is through manual olfaction to identify battery failure. However, this manual assessment is labor-intensive, increasing the workload for workers. Furthermore, the human sense of smell has limited resolution, making it difficult to detect faint odors promptly, leading to missed detections. Additionally, gas leaks occurring after the battery module is assembled with adhesive are difficult to detect manually within the battery pack, necessitating the use of additional detection tools. Summary of the Invention

[0004] This utility model provides an electrical structure, a battery module, and a battery pack to solve the technical problem of difficult cell status detection and improve safety performance.

[0005] To achieve the above and other related objectives, this utility model provides an electrical structure comprising: Integrated busbar; A gas detection unit is connected to the integrated busbar for integration into the integrated busbar, and the gas detection unit includes a sampling unit.

[0006] In one embodiment of the present invention, the gas detection unit further includes an optical signal transmission line and an electrical signal transmission line. The electrical signal transmission line is disposed on the integrated busbar, and the sampling unit is communicatively connected to the electrical signal transmission line through the optical signal transmission line.

[0007] In one embodiment of the present invention, the sampling unit includes a sampling terminal and a sampling gas chamber for collecting gas. The sampling terminal is located in the sampling gas chamber and is adapted to detect the gas concentration in the sampling gas chamber. The sampling terminal is connected to the optical signal transmission line.

[0008] In one embodiment of the present invention, the electrical signal transmission line is disposed inside the integrated busbar.

[0009] In one embodiment of the present invention, the electrical signal transmission line is disposed outside the integrated busbar.

[0010] In one embodiment of the present invention, the integrated busbar extends along a first direction, and there are multiple sampling units. The multiple sampling units are distributed along the first direction on the integrated busbar and are respectively connected to the same electrical signal transmission line through the optical signal transmission line.

[0011] In one embodiment of this utility model, the sampling terminal includes an optical fiber gas sensor or a graphene tilted fiber grating.

[0012] In one embodiment of this utility model, the optical fiber gas sensor includes an optical fiber hydrogen sensor or a chalcogenide glass optical fiber sensor.

[0013] To achieve the above and other related objectives, this utility model also provides a battery module, including the electrical structure described above.

[0014] In one embodiment of the present invention, the battery module further includes a cell assembly, which includes a plurality of cells distributed along a first direction, and the integrated busbar and the gas detection unit are both located on the positive terminal side of the cell.

[0015] In one embodiment of the present invention, there are multiple battery cell groups, which are arranged along a second direction. The sampling unit is located between two adjacent battery cell groups, and each sampling unit is arranged corresponding to at least two adjacent battery cells of the two adjacent battery cell groups.

[0016] In one embodiment of this utility model, the battery cell and the sampling unit are arranged in a one-to-one correspondence.

[0017] In one embodiment of the present invention, the sampling unit has an air inlet. The sampling unit is placed horizontally on the integrated busbar or vertically on the integrated busbar. When the sampling unit is placed horizontally, the vertical height of the air inlet is lower than the vertical height of the air inlet when the sampling unit is placed vertically.

[0018] To achieve the above and other related objectives, this utility model also provides a battery pack, including the battery module as described above.

[0019] The beneficial effects of this utility model are as follows: The electrical structure, battery module, and battery pack proposed in this utility model have a gas detection unit that can sample and detect gases, which is beneficial for timely detection of whether the battery cell is leaking, so as to detect the status of the battery cell and thus detect whether the battery is failing in time, thereby improving safety performance. Based on this, the gas detection unit is connected to the integrated busbar, so that the gas detection unit can be integrated on the integrated busbar, which has a high degree of integration, facilitates modularization, simplifies the structure, saves overall space, and enables the lightweighting and assembly of the overall structure. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0021] In the attached diagram: Figure 1 A schematic diagram of the structure of an embodiment of the electrical structure provided by this utility model; Figure 2 for Figure 1 Top view of the electrical structure; Figure 3 for Figure 1 Front view of the electrical structure; Figure 4 for Figure 3 A partial exploded view of the electrical structure in the middle; Figure 5 A schematic diagram of the second embodiment of the electrical structure provided by this utility model; Figure 6 for Figure 5 Top view of the electrical structure; Figure 7 for Figure 5 Exploded view of the integrated busbar; Figure 8 for Figure 5 A partial exploded view of the electrical structure in the middle; Figure 9 A partial structural schematic diagram of a first embodiment of the battery module provided by this utility model; Figure 10 for Figure 9 A magnified schematic diagram of part A in the middle; Figure 11A partial structural schematic diagram of a second embodiment of the battery module provided by this utility model; Figure 12 for Figure 11 A magnified schematic diagram of part B in the middle; Figure 13 A partial structural schematic diagram of a third embodiment of the battery module provided by this utility model.

[0022] The attached figures are labeled as follows: Integrated busbar 1, bar plate 11, sampling nickel plate 12, gas detection unit 2, optical signal transmission line 21, sampling unit 22, air inlet 221, electrical signal transmission line 23, battery cell group 4, battery cell 41, positive terminal 411. Detailed Implementation

[0023] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0024] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0025] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the present invention. However, it will be apparent to those skilled in the art that embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the present invention.

[0026] See Figures 1 to 4 , Figure 9 and Figure 10In some optional embodiments, the present invention provides an electrical structure including an integrated busbar 1 and a gas detection unit 2. The gas detection unit 2 is connected to the integrated busbar 1 and integrated therein. The gas detection unit 2 includes a sampling section 22, which is used to collect and detect gases, particularly to detect the concentration of gases generated when the battery cell 41 experiences thermal runaway. This allows for timely detection of the leaked gas concentration when the battery cell 41 experiences thermal runaway, thereby enabling monitoring of the battery cell 41's condition.

[0027] Optionally, the integrated busbar 1 includes components such as a flexible circuit board, sampling nickel sheet 12, bar plate 11, and insulating structural components. The battery cells 41 are connected in series and parallel through the bar plate 11. The sampling nickel sheet 12 is connected to the bar plate 11 to collect information such as voltage. The sampling nickel sheet 12 is also connected to the flexible circuit board to transmit the collected voltage and other information through the flexible circuit board. The gas detection unit 2 is integrated on the integrated busbar 1. That is to say, the gas detection unit 2, flexible circuit board, sampling nickel sheet 12, bar plate 11, and insulating structural components are integrated together. The integration is high and can be integrated into a module and installed in the battery module to realize functions such as gas detection, temperature sampling, voltage sampling, high voltage series and parallel connection of battery cells 41, and overcurrent fuse.

[0028] Optionally, the gas detection unit 2 further includes an optical signal transmission line 21 and an electrical signal transmission line 23. The electrical signal transmission line 23 is disposed on the integrated busbar 1. The sampling unit 22 is communicatively connected to the electrical signal transmission line 23 through the optical signal transmission line 21 to realize the conversion of optical signals to electrical signals. Further, the optical signal transmission line 21 includes an optical fiber.

[0029] Optionally, the sampling unit 22 includes sampling terminals and a sampling gas chamber for collecting gas. The sampling terminals are located within the sampling gas chamber and are suitable for detecting the gas concentration within the sampling gas chamber. The sampling terminals are connected to the optical signal transmission line 21. The sampling gas chamber of the sampling unit 22 has an air inlet 221. When the battery cell 41 experiences thermal runaway, some of the leaked gas enters the sampling gas chamber through the air inlet 221. The gas entering the sampling gas chamber can converge in one space, facilitating the sampling terminals' detection of the gas concentration. Furthermore, the sampling terminals and sampling gas chambers are arranged in a one-to-one correspondence.

[0030] Optionally, the integrated busbar 1 extends along the first direction, and there are multiple sampling units 22. The multiple sampling units 22 are distributed on the integrated busbar 1 along the first direction and are respectively connected to the same electrical signal transmission line 23 through corresponding optical signal transmission lines 21. That is, the sampling units 22 are set one-to-one with the optical signal transmission lines 21 and are connected to the electrical signal transmission lines 23 through the corresponding optical signal transmission lines 21, so that multiple sampling units 22 can share the same electrical signal transmission line 23, which is beneficial to simplifying the structure.

[0031] Optionally, the sampling terminals include fiber optic gas sensors or graphene tilted fiber gratings. The graphene tilted fiber grating utilizes graphene's adsorption capacity for gas molecules, converting gas concentration into graphene transmittance, thereby causing a shift in the center wavelength of the cladding mode resonance peak of the graphene tilted fiber grating, which is then fed back as detectable data. Further, the fiber optic gas sensors include fiber optic hydrogen sensors or chalcogenide glass fiber optic sensors, allowing for the selection of appropriate fiber optic sensors to detect different gases depending on the scenario. The fiber optic hydrogen sensor features resistance to electromagnetic interference, high temperature, and high pressure, ensuring test accuracy even under the high temperature and high pressure conditions caused by thermal runaway of lithium batteries. The chalcogenide glass fiber optic sensor includes a fiber core and a coating layer disposed on the outside of the fiber core; the coating layer is typically a graphene oxide coating, and the fiber core has a sensing area.

[0032] Specifically, when the lithium battery cell 41 experiences thermal runaway, hydrogen gas is generated earlier and is easier to capture than other gases. Using a fiber optic hydrogen sensor to detect hydrogen gas is beneficial for improving the efficiency of thermal runaway early warning. When the detected gas is sulfur monoxide or sulfur dioxide, a chalcogenide glass fiber optic sensor can be used. In this case, the coating layer of the chalcogenide glass fiber optic sensor can be removed and it can be fabricated into a flat structure. The fiber core is used for mid-infrared sensing. The evanescent wave leaking during transmission interacts with gas molecules, ultimately causing a change in output intensity at the fiber core output end, thus establishing the relationship between light intensity and gas concentration.

[0033] The electrical structure of the above embodiment can detect whether the battery cell 41 is leaking in a timely manner through the sampling part 22 of the gas detection unit 2, so as to ensure the status of the battery cell 41 is detected in place. Based on this, the gas detection unit 2 is connected to the integrated busbar 1 and integrated into the integrated busbar 1. Information transmission can be realized through the integrated busbar 1. The integration is high, modularization is convenient, which helps to simplify the structure and save the overall installation space, so as to achieve the lightweighting and assembly of the overall structure.

[0034] See Figures 1 to 4 In some alternative embodiments, the electrical signal transmission line 23 is disposed inside the integrated busbar 1, enabling internal wiring without occupying external space. This helps avoid wiring restrictions imposed by other components, reducing wiring limitations and making wiring more flexible. Furthermore, the integrated busbar 1 has an internal mounting channel, and the electrical signal transmission line 23 is disposed within the mounting channel; alternatively, the electrical signal transmission line 23 is a circuit etched inside the integrated busbar 1.

[0035] See Figure 13 In some alternative embodiments, the electrical signal transmission line 23 is located outside the integrated busbar 1, which facilitates observation and assembly operations during the assembly process.

[0036] Furthermore, the electrical signal transmission line 23 and the flexible circuit board can be connected to the same output terminal and communicate with the battery management system through the same output terminal.

[0037] See Figure 1 , Figure 5 , Figures 9 to 13 In some alternative embodiments, the present invention provides a battery module that includes the electrical structure as described in any of the above embodiments.

[0038] Optionally, the battery module further includes a cell assembly 4, which includes a plurality of cells 41 distributed along a first direction. Each cell 41 has a positive terminal side, and the side of the cell 41 with the positive terminal 411 is the positive terminal side of the cell 41. Further, the cell 41 includes a cylindrical cell. It should be noted that in this invention, the distribution direction of the plurality of cells 41 in the same cell assembly 4, the extension direction of the integrated busbar 1, and the first direction are the same, i.e., the X direction in the accompanying drawings.

[0039] Optionally, there may be multiple battery cell groups 4, arranged along the second direction. It should be noted that in this invention, the second direction is the Y-direction shown in the accompanying drawings.

[0040] See Figures 9 to 12 In some alternative embodiments, the integrated busbar 1 and the gas detection unit 2 are both located on the positive terminal side of the battery cell 41. This structural design is not only compact, but also allows the gas detection unit 2 to be close to the positive terminal 411 of the battery cell 41. In other words, the gas detection unit 2 is close to the location of gas leakage when the battery cell 41 experiences thermal runaway, so as to detect the leaked gas in a timely and effective manner.

[0041] See Figure 10 and Figure 11 In some optional embodiments, the sampling section 22 of the gas detection unit 2 is located between two adjacent battery cell groups 4. Each sampling section 22 is arranged corresponding to at least two adjacent battery cells 41 of the two adjacent battery cell groups 4. In other words, one battery cell 41 of a battery cell group 4 and another adjacent battery cell 41 of an adjacent battery cell group 4 can share the same sampling section 22 for detection, which helps to reduce the number of parts and simplify the structure.

[0042] See Figure 13 In some optional embodiments, the battery cells 41 and the sampling units 22 are arranged in a one-to-one correspondence, so that the state of each battery cell 41 can be detected independently. This is beneficial for accurately detecting the state of each battery cell 41 and for eliminating detection blind spots. When a battery cell 41 experiences a slight failure, the sampling unit 22 can detect the failure risk of the battery cell 41 in advance, thereby helping to avoid the inability to detect the state of the battery cell 41 due to the failure of voltage and temperature acquisition and judgment.

[0043] See Figures 1 to 12 In some optional embodiments, the sampling chamber of the sampling unit 22 has an air inlet 221. The sampling unit 22 is placed horizontally on the integrated busbar 1 or vertically on the integrated busbar 1. When the sampling unit 22 is placed horizontally, the vertical height of the air inlet 221 is lower than the vertical height of the air inlet 221 when the sampling unit 22 is placed vertically. It can be understood that in this utility model, the vertical direction and the height direction of the battery cell 41 are the same, that is, the Z direction in the figure.

[0044] Optionally, the sampling gas chamber can be placed horizontally (i.e., the sampling unit 22 is in a horizontal position) or vertically (i.e., the sampling unit 22 is in a vertical position). The sampling gas chamber includes a cylindrical main body with a chamber for containing gas. One end of the main body extends axially to form a protruding air inlet. An air inlet 221 is located on the end face of the air inlet away from the main body and communicates with the chamber. Gas enters the chamber through the air inlet 221. The air inlet is cylindrical, with an outer diameter smaller than that of the main body. The sum of the axial length of the air inlet and the axial length of the main body is greater than the outer diameter of the main body. In other words, the vertical height occupied by the sampling gas chamber when it is horizontal is less than that when it is vertical, thus making the overall vertical height occupied by the sampling unit 22 less when it is horizontal than when it is vertical, which is beneficial for adapting to installation requirements in spaces of different heights.

[0045] In addition, the sampling chamber of sampling unit 22 can be placed either horizontally or vertically, depending on the type of gas being detected. For details, see [link to documentation]. Figure 9 and Figure 10 The sampling chamber is placed vertically on the integrated busbar 1. The inlet 221 of the sampling chamber is located higher than when the sampling chamber is laid flat. Gases less dense than air tend to flow and accumulate at higher positions. Vertical placement of the sampling chamber is advantageous for collecting gases less dense than air, such as hydrogen. (See 11 and...) Figure 12 The sampling gas chamber is placed horizontally on the integrated busbar 1. The position of the air inlet 221 of the sampling gas chamber is lower than that of the sampling gas chamber when it is placed vertically. Gases with a density greater than air are more likely to flow and gather at the lower position. Placing the sampling gas chamber horizontally is beneficial for collecting gases with a density greater than air, such as sulfur monoxide or sulfur dioxide.

[0046] The battery module in the above embodiment has a flexible placement of the sampling unit 22 to adapt to the detection needs of different scenarios.

[0047] See Figure 4 , Figures 9 to 12 In some optional embodiments, the battery module further includes a Battery Management System (BMS), which is electrically connected to the electrical structure to receive and process data collected by the electrical structure. The gas detection unit 2 includes a photodetector. When the gas concentration in the sampling chamber changes, it causes a change in the optical properties of the light signal. The photodetector receives the light signal and converts it into an electrical signal, which is then output to the battery management system. The battery management system uses the electrical signal to determine whether the gas concentration is within a preset threshold range, thereby judging the health status of the battery cell 41. If the detected gas concentration exceeds the preset threshold, the battery management system outputs an alarm and stops charging and discharging.

[0048] See Figure 1 , Figure 5 , Figure 9 , Figure 11 and Figure 13 In some alternative embodiments, the present invention also provides a battery pack, which includes the battery module as described in any of the above embodiments.

[0049] The electrical structure, battery module, and battery pack of this utility model can detect gas leakage when the battery cell 41 experiences thermal runaway through the sampling part 22 of the gas detection unit 2. This allows the battery cell 41 to be detected by detecting gas leakage, which helps to improve safety performance. Furthermore, the gas detection unit 2 can be integrated into the integrated busbar 1, resulting in a high degree of modularity and a simple structure.

[0050] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. An electrical structure, characterized by, include: Integrated busbar; A gas detection unit is connected to the integrated busbar and integrated therein. The gas detection unit includes a sampling unit, an optical signal transmission line, and an electrical signal transmission line. The electrical signal transmission line is disposed on the integrated busbar, and the sampling unit is communicatively connected to the electrical signal transmission line through the optical signal transmission line.

2. The electrical structure of claim 1, wherein, The sampling unit includes a sampling terminal and a sampling gas chamber for collecting gas. The sampling terminal is located in the sampling gas chamber and is adapted to detect the gas concentration in the sampling gas chamber. The sampling terminal is connected to the optical signal transmission line.

3. The electrical structure of claim 1, wherein, The electrical signal transmission lines are located inside the integrated busbar.

4. The electrical structure of claim 1, wherein, The electrical signal transmission line is located outside the integrated busbar.

5. The electrical structure of claim 1, wherein, The integrated busbar extends along a first direction, and there are multiple sampling units. The multiple sampling units are distributed along the first direction on the integrated busbar and are respectively connected to the same electrical signal transmission line through the optical signal transmission line.

6. The electrical structure of claim 2, wherein, The sampling terminals include fiber optic gas sensors or graphene tilted fiber optic gratings.

7. The electrical structure of claim 6, wherein, The fiber optic gas sensor includes a fiber optic hydrogen sensor or a chalcogenide glass fiber optic sensor.

8. A battery module, characterized by, Includes the electrical structure as described in any one of claims 1 to 7.

9. The battery module of claim 8, wherein, The battery module further includes a cell assembly, which comprises multiple cells distributed along a first direction. The integrated busbar and the gas detection unit are both located on the positive terminal side of the cell.

10. The battery module of claim 9, wherein, The number of battery cell groups is multiple, and the multiple battery cell groups are arranged along the second direction. The sampling unit is located between two adjacent battery cell groups, and each sampling unit is arranged corresponding to at least two adjacent battery cells of the two adjacent battery cell groups.

11. The battery module of claim 9, wherein, The battery cells and the sampling units are arranged in a one-to-one correspondence.

12. The battery module of claim 9, wherein, The sampling unit has an air inlet. The sampling unit is placed horizontally on the integrated busbar or vertically on the integrated busbar. When the sampling unit is placed horizontally, the vertical height of the air inlet is lower than the vertical height of the air inlet when the sampling unit is placed vertically.

13. A battery pack, characterized by Includes the battery module as described in any one of claims 8 to 12.

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