A battery cell voltage acquisition system

Abstract

The utility model provides a kind of electric core voltage acquisition system, it is related to battery technical field.A kind of electric core voltage acquisition system, for collecting the voltage of electric core in battery pack or module, including first sampling structure, the first sampling structure includes: end plate support, installation slot is provided on the end plate support;Tab support, the tab of the electric core is set on the tab support, the tab support is connected with the end plate support;Sampling line, the end of the sampling line is provided with sampling terminal, the sampling terminal is embedded in the installation slot of the end plate support, the sampling terminal is electrically connected with the tab.By integrating design of end plate support, tab support and sampling line bundle, modular first sampling structure is formed, traditional FPC scheme is replaced, material cost and assembly complexity are significantly reduced, and system grouping automation degree and efficiency are improved.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, specifically relating to a cell voltage acquisition system. Background Technology

[0002] With the rapid development of electric vehicles, the market demand for extended driving range continues to rise, leading to increasingly higher requirements for lithium-ion battery energy density and system assembly efficiency. As battery modules become larger, efficient voltage signal sampling for high-cell power batteries is crucial.

[0003] Currently, power battery modules commonly use a single FPC (Flexible Printed Circuit) for cell voltage sampling and signal transmission. Because FPC is flexible and has low rigidity, this process must be performed during the battery module assembly stage. During assembly, the entire FPC is laid flat on the bottom of the module, facing the larger surface of the cell. The voltage sampling signal is transmitted through the copper traces on the FPC to the voltage sampling connector at the end of the module.

[0004] Current batteries use a single FPC for sampling, requiring step-by-step laying, hot riveting, and welding during assembly. This process is complex and involves numerous steps, resulting in low material integration and the inability to automate assembly. This impacts battery system assembly efficiency and increases manufacturing costs. Furthermore, using a single FPC for sampling means that in the event of circuit failure, the only solution is to remove the battery cover, cell stack, and end plate, replacing the entire FPC. This reduces maintainability and renders the battery essentially unrepairable. Utility Model Content

[0005] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a battery cell voltage acquisition system.

[0006] The objective of this utility model can be achieved through the following technical solution: a cell voltage acquisition system for acquiring the voltage of cells in a battery pack or module, characterized in that it includes a first sampling structure, the first sampling structure comprising:

[0007] An end plate bracket, wherein the end plate bracket is provided with a mounting groove;

[0008] A tab support is provided, wherein the tabs of the battery cell are disposed on the tab support, and the tab support is connected to the end plate support;

[0009] A sampling line is provided at one end of the sampling line. The sampling terminal is embedded in the mounting groove of the end plate bracket and is electrically connected to the electrode tab.

[0010] As a further improvement of this utility model, a first inclined surface is provided on the side of the end plate bracket facing the battery cell, and the sampling terminal has a first bent portion, which passes through the end plate bracket and fits against the first inclined surface.

[0011] As a further improvement of this utility model, the first sampling structure further includes a first adapter piece, one end of which is connected to the first bent portion, and the other end of which is connected to the electrode tab.

[0012] As a further improvement of this utility model, the first adapter piece is provided with a first protrusion and a second protrusion, and the protrusion direction of the first protrusion is opposite to that of the second protrusion.

[0013] As a further improvement of this utility model, at least one end of the electrode bracket is provided with a buckle, and a snap-fit ​​element is provided at the corresponding position of the end plate bracket, and the buckle is snapped into the snap-fit ​​element.

[0014] As a further improvement of this utility model, the snap-fit ​​member located on one side of the end plate bracket is disposed between two adjacent first inclined surfaces.

[0015] As a further improvement of this utility model, a second sampling structure is also included. The second sampling structure includes: an FPC body, an FPC mounting bracket, and an FPC sampling connector. The FPC mounting bracket is disposed between two adjacent modules in the width direction of the battery pack. One end of the FPC body is connected to the end plate bracket, and the other end of the FPC body is connected to the FPC mounting bracket. The FPC body is electrically connected to the electrode tab, and the FPC sampling connector is disposed on the end plate bracket and electrically connected to the FPC body.

[0016] As a further improvement of this utility model, the second sampling structure further includes an FPC nickel sheet and a second adapter piece. The FPC nickel sheet is disposed on the FPC mounting bracket, the FPC mounting bracket is provided with a second inclined surface, the FPC nickel sheet is provided with a second bent portion, the second bent portion is in contact with the second inclined surface, one end of the FPC nickel sheet is electrically connected to the FPC body, the other end of the FPC nickel sheet is electrically connected to the second adapter piece, and the second adapter piece is electrically connected to the tab.

[0017] As a further improvement of this utility model, it also includes a hot riveting post, which is inserted into the end plate bracket and the FPC mounting bracket for riveting the sampling terminal to the end plate bracket and the FPC nickel sheet to the FPC mounting bracket.

[0018] As a further improvement of this utility model, it also includes a leakage detection sensor, which is provided with a positive detection interface and a negative detection interface. A first resistor and a second resistor are connected in parallel between the positive detection interface and the negative detection interface. The resistance value of the first resistor is fixed, and the resistance value of the second resistor varies according to the degree of leakage in the battery pack.

[0019] Based on the above technical solution, this utility model can produce at least the following technical effects:

[0020] 1. By integrating the end plate bracket, electrode bracket and sampling harness into a modular first sampling structure, the traditional FPC solution is replaced, which significantly reduces material costs and assembly complexity, improves the automation and efficiency of system assembly, and at the same time, when the sampling on the outside of the module fails, the first sampling structure at the corresponding fault location can be disassembled and replaced, which improves the maintainability of the battery pack.

[0021] 2. By introducing a second sampling structure in the cell series region of the module, FPC is used only in the necessary areas, which greatly reduces the area of ​​FPC used, reduces costs, and realizes a hybrid voltage sampling architecture of local FPC + main wire harness.

[0022] 3. By integrating a leakage detection sensor and adopting a parallel variable resistor design, real-time and sensitive monitoring of electrolyte leakage in the battery pack can be achieved, significantly improving battery system safety and preventing the risk of thermal runaway. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the battery cell voltage acquisition system.

[0025] Figure 2 This is a schematic diagram of the first sampling structure and the second sampling structure.

[0026] Figure 3 This is the main view of the first sampling structure.

[0027] Figure 4 This is a schematic diagram of the first sampling structure.

[0028] Figure 5 This is a schematic diagram of the sampling terminal and the first adapter piece in the first sampling structure.

[0029] Figure 6 This is a schematic diagram of the second sampling structure.

[0030] Figure 7 This is a schematic diagram of the structure of a leak detection sensor.

[0031] In the diagram, 100 is the battery module; 110 is the tab; 200 is the first sampling structure; 210 is the end plate bracket; 211 is the mounting groove; 212 is the first inclined surface; 213 is the snap-fit ​​component; 220 is the tab bracket; 221 is the buckle; 230 is the sampling line; 240 is the sampling terminal; 241 is the first bend; 250 is the first adapter piece; 251 is the first protrusion; 252 is the second protrusion; 300 is the second sampling structure; and 310 is the second sampling structure. FPC body; 320, FPC mounting bracket; 321, second inclined surface; 330, FPC sampling connector; 340, FPC nickel sheet; 341, second bend; 350, second adapter piece; 400, hot riveting post; 500, leakage detection sensor; 510, first resistor; 520, second resistor; 530, positive power interface; 540, negative power interface; 550, positive detection interface; 560, negative detection interface. Detailed Implementation

[0032] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this utility model are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the attached figure). If the specific posture changes, the directional indication will also change accordingly. Furthermore, in this utility model, descriptions involving "first," "second," "a," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly defined. In this utility model, unless otherwise explicitly specified and defined, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise explicitly defined. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to the specific circumstances. Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope claimed by this utility model.

[0033] The following are specific embodiments of this utility model, in conjunction with the accompanying drawings. Figure 1-7 The technical solution of this utility model will be further described below, but this utility model is not limited to the following embodiments.

[0034] This utility model provides a cell voltage acquisition system, the core of which is to achieve efficient, stable and low-cost acquisition of the voltage signal of the battery module 100 through structural integration and sampling path optimization, while taking into account the efficiency of automated assembly line and subsequent maintainability, and integrating leakage detection function to improve the safety of the battery system.

[0035] This cell voltage acquisition system is mainly used to collect voltage signals from multiple cells within a battery pack or module, and is particularly suitable for large power battery systems composed of multiple battery modules 100 connected in series or parallel. The system mainly consists of three parts: a first sampling structure 200, a second sampling structure 300, and a leakage detection sensor 500. These three parts work together to ensure the accuracy and stability of voltage sampling and to achieve real-time monitoring of electrolyte leakage inside the battery pack.

[0036] The first sampling structure 200 is mainly responsible for collecting the cell voltage signals on both sides of the module in the battery pack. The first sampling structure 200 includes an end plate bracket 210, a tab bracket 220, a sampling line 230, and a sampling terminal 240. The end plate bracket 210 is usually made of high-strength insulating plastic, and has multiple mounting slots 211 on the side facing the cell for embedding the sampling terminal 240. The sampling terminal 240 is a metal conductive component. One end of it is crimped and fixed to the sampling line 230, and the other end is designed with a first bend 241. After passing through the end plate bracket 210, the bend fits against the first inclined surface 212 on the inner side of the end plate bracket 210, ensuring stable positioning and good contact of the sampling terminal 240 inside the bracket.

[0037] The tab bracket 220 supports and positions the tabs 110 of the battery cell, and it is quickly assembled with the end plate bracket 210 via a snap-fit ​​structure 221. The tab bracket 220 has a snap-fit ​​221 at at least one end, while the end plate bracket 210 has a corresponding snap-fit ​​member 213. The snap-fit ​​221 and the snap-fit ​​member 213 engage with each other, ensuring convenient installation and a stable structure. Preferably, the snap-fit ​​member 213 located on one side of the end plate bracket 210 is positioned between two adjacent first inclined surfaces 212, saving space and enhancing structural compactness.

[0038] The sampling terminal 240 is electrically connected to the battery cell tab 110 via a first adapter piece 250. The first adapter piece 250 is L-shaped, with one end welded to the first bent portion 241 of the sampling terminal 240 and the other end welded to the battery cell tab 110, thus forming a complete conductive path from the battery cell tab 110 through the first adapter piece 250, the sampling terminal 240, and the sampling line 230. Preferably, to improve the structural stability of the adapter piece under stress conditions, the first adapter piece 250 is provided with a first protrusion 251 and a second protrusion 252, with opposite protrusion directions, forming a structure similar to a reinforcing rib, effectively enhancing the rigidity of the adapter piece and preventing the welding point from breaking due to stress concentration.

[0039] The second sampling structure 300 is mainly responsible for collecting voltage signals at the series connection nodes of two adjacent cells in the battery module 100. Since this area is usually located inside the module, space is limited, and the number of voltage sampling points is relatively small, a flexible printed circuit board (FPC) solution is adopted.

[0040] The second sampling structure 300 includes an FPC body 310, an FPC mounting bracket 320, an FPC sampling connector 330, an FPC nickel sheet 340, a second adapter piece 350, and a hot-riveting post 400. The FPC mounting bracket 320 is disposed between two adjacent series-connected cells and is used to support the FPC body 310. One end of the FPC body 310 is fixed to the end plate bracket 210, and the other end is fixed to the FPC mounting bracket 320, and is electrically connected to the cell tab 110 through the FPC nickel sheet 340 and the second adapter piece 350.

[0041] The FPC nickel sheet 340 also has a second bend 341, which fits against the second inclined surface 321 on the FPC mounting bracket 320 to ensure stable installation of the nickel sheet on the bracket. One end of the FPC nickel sheet 340 is connected to the FPC body 310 by welding or crimping, and the other end is welded to the second adapter piece 350. The second adapter piece 350 is then welded to the cell electrode tab 110, thereby constructing a conductive path from the cell electrode tab 110 through the second adapter piece 350, the FPC nickel sheet 340 to the FPC body 310. The FPC sampling connector 330 is disposed on the end plate bracket 210 and electrically connected to the FPC body 310, and is used to output the collected voltage signal to the external voltage sampling assembly harness.

[0042] The hot-riveting post 400 penetrates the end plate bracket 210 and the FPC mounting bracket 320. On the one hand, it is used to hot-rivet the sampling terminal 240 to the end plate bracket 210, and on the other hand, it is used to hot-rivet the FPC nickel sheet 340 to the FPC mounting bracket 320, so as to ensure structural stability and electrical reliability.

[0043] Compared to the traditional sampling scheme that uses a large FPC to cover all cells, this invention uses a small-sized FPC only in the cell series connection area, which greatly reduces the area of ​​the FPC and the number of pins, thereby reducing material costs and assembly complexity.

[0044] This hybrid architecture of "sampling from both ends of the wiring harness + sampling from the middle FPC" is highly integrated in the wiring harness sampling section. During production line assembly, only the L-shaped adapter piece needs to be welded to the battery cell tab 110, eliminating the cumbersome processes of laying flat, hot riveting, and multi-point welding required in traditional FPC solutions, greatly improving the efficiency of automated assembly. In addition, if a sampling structure on one side fails, the corresponding first sampling structure 200 can be directly disassembled for replacement or repair without disassembling the entire module or replacing the entire FPC, significantly improving the maintainability and economy of the system.

[0045] To further enhance the safety of the battery system, this invention also integrates a leakage detection sensor 500. This sensor is positioned inside the battery pack in areas prone to leakage, such as the bottom or sidewall of the module. The sensor has a positive detection interface 550 and a negative detection interface 560, with a first resistor 510 and a second resistor 520 connected in parallel between them. The first resistor 510 is a fixed-value resistor, while the second resistor 520 is a variable resistor whose resistance changes depending on the degree of electrolyte contact. When battery leakage occurs, electrolyte seeps into the sensor's detection area, causing a change in the resistance of the second resistor 520, thereby altering the total resistance value after parallel connection.

[0046] Specifically, the sensor has both a positive power interface 530 and a negative power interface 540, powered by a 5V DC supply from the mainboard BMU via a power supply harness. A current-limiting pull-up resistor is connected in series on the positive power interface 530 to prevent excessive current from damaging the sensor. The positive power interface 530 and the positive detection interface 550, and the negative power interface 540 and the negative detection interface 560, are connected in parallel via internal wiring, ensuring that the first resistor 510 and the second resistor 520 are always in parallel. The mainboard BMU collects the voltage value between the positive and negative detection interfaces 560 in real time via the detection harness. This voltage value changes with the value of the parallel resistor. When the battery is not leaking, the resistance of the second resistor 520 is extremely high, and the total parallel resistance is close to the resistance of the first resistor 510, keeping the detection voltage within a preset safe range. When leakage occurs, the resistance of the second resistor 520 drops sharply, the total parallel resistance decreases accordingly, and the detection voltage decreases accordingly. The mainboard BMU determines the degree of leakage based on the magnitude and trend of the voltage change and triggers an alarm or cuts off the battery output, achieving active safety protection.

[0047] In summary, this cell voltage acquisition system achieves efficient wire harness acquisition of cell voltages on the outside of the module through the first sampling structure 200, and accurate FPC acquisition of the voltages of series nodes between adjacent cells in the battery module 100 through the second sampling structure 300. The combination of these two structures forms a hybrid sampling architecture, which significantly reduces system cost, improves assembly efficiency, and enhances maintainability while ensuring sampling accuracy. Simultaneously, the integrated leakage detection sensor 500 monitors electrolyte leakage in real time through a parallel resistor network, providing critical safety signals to the mainboard BMU. This invention is not only suitable for electric vehicle power battery packs but can also be widely applied to large and medium-sized battery systems in energy storage power stations, electric ships, and rail transit, possessing broad market prospects and promotional value.

[0048] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A cell voltage acquisition system for acquiring voltages of cells in a battery pack or module, the system comprising: Including a first sampling structure (200), the first sampling structure (200) includes: An end plate bracket (210) is provided with a mounting groove (211); A tab support (220) is provided on which the tabs (110) of the battery cell are disposed, and the tab support (220) is connected to the end plate support (210); A sampling line (230) is provided at its end with a sampling terminal (240), the sampling terminal (240) is embedded in the mounting groove (211) of the end plate bracket (210), and the sampling terminal (240) is electrically connected to the tab (110).

2. The system according to claim 1, wherein, The end plate bracket (210) has a first inclined surface (212) on the side facing the battery cell, and the sampling terminal (240) has a first bent portion (241), which passes through the end plate bracket (210) and fits against the first inclined surface (212).

3. The system according to claim 2, wherein, The first sampling structure (200) further includes a first adapter piece (250), one end of which is connected to the first bent portion (241), and the other end of which is connected to the tab (110).

4. The system according to claim 3, wherein, The first adapter plate (250) is provided with a first protrusion (251) and a second protrusion (252), and the protrusion direction of the first protrusion (251) is opposite to that of the second protrusion (252).

5. A cell voltage acquisition system according to claim 2, characterized in that, At least one end of the tab support (220) is provided with a buckle (221), and a snap-fit ​​member (213) is provided at the corresponding position of the end plate support (210), and the buckle (221) snaps into the snap-fit ​​member (213).

6. The cell voltage acquisition system according to claim 5, characterized in that, The snap-fit ​​(213) on one side of the end plate bracket (210) is disposed between two adjacent first inclined surfaces (212).

7. The cell voltage acquisition system according to claim 1, characterized in that, It also includes a second sampling structure (300), which includes: an FPC body (310), an FPC mounting bracket (320), and an FPC sampling connector (330). The FPC mounting bracket (320) is disposed between two adjacent series-connected cells. One end of the FPC body (310) is connected to the end plate bracket (210), and the other end of the FPC body (310) is connected to the FPC mounting bracket (320). The FPC body (310) is electrically connected to the tab (110), and the FPC sampling connector (330) is disposed on the end plate bracket (210) and electrically connected to the FPC body (310).

8. A cell voltage acquisition system according to claim 7, characterized in that, The second sampling structure (300) further includes an FPC nickel sheet (340) and a second adapter piece (350). The FPC nickel sheet (340) is disposed on the FPC mounting bracket (320). The FPC mounting bracket (320) is provided with a second inclined surface (321). The FPC nickel sheet (340) is provided with a second bent portion (341). The second bent portion (341) is in contact with the second inclined surface (321). One end of the FPC nickel sheet (340) is electrically connected to the FPC body (310). The other end of the FPC nickel sheet (340) is electrically connected to the second adapter piece (350). The second adapter piece (350) is electrically connected to the tab (110).

9. A cell voltage acquisition system according to claim 8, characterized in that, It also includes a hot riveting post (400), which is inserted into the end plate bracket (210) and the FPC mounting bracket (320) for riveting the sampling terminal (240) to the end plate bracket (210) and the FPC nickel sheet (340) to the FPC mounting bracket (320).

10. A cell voltage acquisition system according to claim 1, characterized in that, It also includes a leakage detection sensor (500), which is provided with a positive detection interface (550) and a negative detection interface (560). A first resistor (510) and a second resistor (520) are connected in parallel between the positive detection interface (550) and the negative detection interface (560). The resistance value of the first resistor (510) is fixed, and the resistance value of the second resistor (520) varies according to the degree of leakage in the battery pack.

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