Battery module and battery box

Abstract

The invention discloses a battery module, which is characterized in that two battery monitoring wafers are used for jointly monitoring the voltage of a plurality of battery cells which are sequentially connected in series, the pole of the first polarity of each battery cell is coupled to one of the two battery monitoring wafers, and the pole of the second polarity of each battery cell is coupled to one of the two battery monitoring wafers. And the voltage information of each battery cell is calculated according to the voltage sampling results of the two battery monitoring wafers. According to the battery module structure, the pole of each battery cell only needs to be connected to the battery monitoring wafer close to the side of the pole, or is connected to the pole, on the same side as the pole, of the adjacent battery cell, so that the voltage sampling wiring harness cost of the battery module based on the blade battery cells can be reduced to a great extent; meanwhile, the wiring difficulty can be reduced and the electric leakage risk problem can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and more specifically, to a battery module and a battery box. Background Art

[0002] Blade cells have been widely used in automotive battery packs in recent years, such as BYD's long blade and Honeycomb Energy's short blade. As a new product application, it also brings some new use cases to the sampling board of the battery management system (BMS). The typical feature of blade cells is that they are relatively long (0.6 to 2 meters), with the positive and negative poles at the ends of the long sides of the cell, so their series connection when grouped is different from that of previous square batteries. Summary of the Invention

[0003] In view of this, the present invention provides a new battery module to solve the problems of high cost and difficult wiring of the voltage sampling harness of the battery module based on blade cells in the prior art.

[0004] In a first aspect, the present invention provides a battery module, characterized by comprising:

[0005] A plurality of battery cells connected in series;

[0006] Two battery monitoring chips are used to jointly monitor the voltages of the multiple battery cells, wherein the first polarity pole of each battery cell is coupled to one of the two battery monitoring chips, and the second polarity pole is coupled to the other of the two battery monitoring chips.

[0007] Preferably, the multiple battery cells are arranged in parallel laterally, and poles of the same polarity of two adjacent battery cells are not located on the same side.

[0008] Preferably, the battery monitoring chip is placed on both sides of the multiple battery cells arranged in parallel in the transverse direction, and is placed substantially perpendicular to the multiple battery cells.

[0009] Preferably, the positive electrode column of the (n+1)th battery cell and the negative electrode column of the (n)th battery cell are short-circuited by a wiring harness on the same side of the multiple battery cells arranged in parallel laterally, where n is a natural number greater than 0 and less than the number of battery cells.

[0010] Preferably, the poles of the battery cells are directly connected to the battery monitoring chip, or are connected to the battery monitoring chip through poles of different polarities of adjacent battery cells.

[0011] Preferably, each of the battery monitoring chips has multiple voltage sampling pins, and two adjacent voltage sampling pins constitute a voltage sampling channel. Except for one voltage sampling channel in the two battery monitoring chips that samples the voltage of the first or last battery cell, each of the remaining voltage sampling channels samples the sum of the voltages of two adjacent battery cells.

[0012] Preferably, the sum of the numbers of voltage sampling channels of the two battery monitoring chips is equal to the number of the battery cells.

[0013] Preferably, when the number of the plurality of battery cells is an even number, the number of voltage sampling channels of each battery monitoring chip is half the number of the battery cells.

[0014] Preferably, when the number of the plurality of battery cells is an odd number, the difference between the numbers of the voltage sampling channels of the two battery monitoring chips is 1.

[0015] Preferably, the two battery monitoring chips sequentially and alternately sample the voltage sum of the i-th and i+1-th battery cells, wherein i is a natural number greater than 0 and not greater than the difference between the number of battery cells and 1.

[0016] Preferably, the voltage of each battery cell is calculated based on the sampling results of all voltage sampling channels of the two battery monitoring chips.

[0017] In a second aspect, a battery box is provided, characterized in that it includes:

[0018] A plurality of the above battery modules.

[0019] The present invention provides a battery module that uses two battery monitoring chips to jointly monitor the voltages of multiple battery cells connected in series, and the first polarity pole of each battery cell is coupled to one of the two battery monitoring chips, and the second polarity pole is coupled to one of the two battery monitoring chips, so as to jointly calculate the voltage information of each battery cell based on the voltage sampling results of the two battery monitoring chips. The battery module structure of the present invention can significantly reduce the cost of the voltage sampling harness of the battery module based on the blade cell, because the pole of each battery cell only needs to be connected to the battery monitoring chip on the side close to the pole, or to the pole of the adjacent battery cell on the same side as the pole. At the same time, it can also reduce the difficulty of wiring and solve the risk of leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0021] Figure 1 A schematic diagram of a battery module according to a comparative example of the present invention;

[0022] Figure 2 is a schematic diagram of a battery module according to another comparative example of the present invention;

[0023] Figure 3 is a schematic diagram of a battery module according to an embodiment of the present invention;

[0024] Figure 4 Schematic diagram of a voltage sampling method for a battery module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is described below based on the following embodiments, but the present invention is not limited to these embodiments. In the detailed description of the present invention below, certain specific details are described in detail. Those skilled in the art can fully understand the present invention without these details. To avoid obscuring the essence of the present invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0026] Furthermore, persons of ordinary skill in the art will appreciate that the figures provided herein are for illustration purposes only and are not necessarily drawn to scale.

[0027] At the same time, it should be understood that in the following description, "circuit" refers to a conductive loop composed of at least one element or subcircuit connected electrically or electromagnetically. When an element or circuit is said to be "connected to" another element or an element / circuit is said to be "connected" between two nodes, it can be directly coupled or connected to the other element or there can be intermediate elements. The connection between the elements can be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there are no intermediate elements between the two.

[0028] Unless the context clearly requires otherwise, throughout the specification and claims, the words "include," "comprising," and similar words should be construed in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to."

[0029] In the description of the present invention, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0030] Figure 1 Schematic diagram of a battery module of a comparative example of the present invention. Figure 1 As shown, in the battery module of this comparative example, the battery module includes 12 battery cells Cell1 to Cell12 and an analog front-end circuit AFE. Battery cells Cell1 to Cell12 are all flat, long, and blade-shaped battery cells. The dimensions of existing blade battery cells are approximately 0.6 to 2 meters in length, about 10 centimeters in width, and about 2 centimeters in thickness. Through this unique battery cell shape and structural design, efficient integration and performance improvement of the battery system can be achieved. Of course, it is understandable that the present invention does not limit the specific dimensions of the blade battery cells.

[0031] like Figure 1 As shown in , the analog front-end circuit AFE is arranged on one side of the blade battery cell, and the upper side is taken as an example here. In this comparative example, the analog front-end circuit AFE samples the voltage of each single battery cell, that is, each voltage sampling channel composed of two sampling pins only samples the voltage of one battery cell. Therefore, the two poles of each battery cell need to be coupled to the analog front-end circuit AFE. Pulling all the voltage sampling harnesses connected to the poles to the voltage sampling board in the analog front-end circuit AFE will inevitably lead to an increase in the wiring harness cost and the connector cost, which further leads to low space utilization of the battery module. At the same time, because the blade batteries are close to each other, if in some application scenarios, the analog front-end circuit AFE needs to be arranged on the left or right side of the blade battery cell, it will further increase the difficulty of wiring.

[0032] Figure 2 Schematic diagram of a battery module of another comparative example of the present invention. This comparative example is an improved battery module compared to the above comparative example. In this comparative example, Figure 2 As shown, one pole of the battery cell is connected to the analog front-end circuit AFE, and the other pole uses the metal aluminum shell of the blade battery cell as a conductor to connect the battery cell sampling point far away from the analog front-end circuit AFE to the shell of the corresponding battery cell. In this way, the sampling point can be obtained by connecting the battery cell shell at the analog front-end circuit AFE end, as shown in FIG. Figure 2 The positive terminals of the cells at Cells 1 / 3 / 5 / 7 / 9 / 11 are connected to the metal aluminum casing of the cells. While this solution effectively solves the problem of multiple and long voltage wiring harnesses, the cell casings are charged. If a vehicle uses this battery module, there is a risk of leakage throughout the vehicle, posing a safety risk.

[0033] Based on this, the present invention provides a new battery module based on blade cells, which adopts two battery monitoring chips to jointly monitor the voltages of multiple battery cells connected in series, and the pole of the first polarity of each battery cell is coupled to one of the two battery monitoring chips, and the pole of the second polarity is coupled to the other of the two battery monitoring chips, so as to reduce the voltage sampling harness cost of the battery module based on blade cells, and solve the problems of harness wiring difficulties and leakage risks.

[0034] Specifically, the pole of each battery cell is directly connected to the battery monitoring chip, or is connected to the battery monitoring chip through the pole of the adjacent battery cell with different polarity.

[0035] Preferably, the multiple battery cells are arranged in parallel in a transverse direction, and the directions of the multiple battery cells are alternately placed. Specifically, the alternating directions of the multiple battery cells means that if the placement direction of the nth battery cell is the negative electrode column on the left and the positive electrode column on the right, then the placement direction of the n+1th battery cell is the positive electrode column on the left and the negative electrode column on the right, so as to facilitate the sequential series connection of the multiple battery cells, where n is a natural number greater than 0 and less than the number of battery cells.

[0036] The battery monitoring chip is placed on both sides of the multiple battery cells arranged in parallel in a transverse direction and is positioned substantially perpendicular to the multiple battery cells. Furthermore, the positive electrode of the (n+1)th battery cell and the negative electrode of the (n)th battery cell are short-circuited by a wiring harness on the same side of the multiple battery cells arranged in parallel in a transverse direction.

[0037] Each battery monitoring chip has multiple voltage sampling pins, and every two adjacent voltage sampling pins constitute a voltage sampling channel. Except for one voltage sampling channel in the two battery monitoring chips that samples the voltage of the first or last battery cell, each of the other sampling channels samples the sum of the voltages of the two adjacent battery cells.

[0038] The sum of the number of voltage sampling channels on the two battery monitoring chips is equal to the number of battery cells. When the number of battery cells is even, the number of voltage sampling channels on each battery monitoring chip is half the number of battery cells. When the number of battery cells is odd, the difference between the number of voltage sampling channels on the two battery monitoring chips is 1.

[0039] Furthermore, the two battery monitoring chips sequentially and alternately sample the sum of the i-th and i+1-th battery cells until the last voltage sampling channel directly samples the voltage of the last battery cell. Here, i is a natural number greater than 0 and not greater than the difference between the number of battery cells and 1. The battery module infers the voltage of each battery cell based on the sampling results of all voltage sampling channels of the two battery monitoring chips.

[0040] It can be seen that the battery module of the present invention can effectively solve the problems of high wiring harness cost, difficult wiring harness routing and leakage risk in battery modules based on blade cells.

[0041] Figure 3 This is a schematic diagram of a battery module according to an embodiment of the present invention. In this embodiment, the battery module's battery pack is described using a battery pack comprising 12 blade cells connected in series. The battery module includes 12 blade cells connected in series and two battery monitoring chips, AFE1 and AFE2. AFE1 and AFE2 jointly monitor the voltage of the 12 series-connected cells.

[0042] Preferably, the 12 battery cells are arranged in parallel horizontally, and the directions of the 12 battery cells are placed alternately. Here, the placement direction of the first battery cell is the negative electrode column on the left and the positive electrode column on the right; the placement direction of the second battery cell is the positive electrode column on the left and the negative electrode column on the right; the placement direction of the third battery cell is the negative electrode column on the left and the positive electrode column on the right; and so on. In addition, the positive electrode column of the second battery cell and the negative electrode column of the first battery cell are short-circuited by the wiring harness on the left side of the 12 battery cells arranged in parallel horizontally; the positive electrode column of the third battery cell and the negative electrode column of the second battery cell are short-circuited by the wiring harness on the right side of the 12 battery cells arranged in parallel horizontally; the positive electrode column of the fourth battery cell and the negative electrode column of the third battery cell are short-circuited by the wiring harness on the left side of the 12 battery cells arranged in parallel horizontally; and so on. According to Figure 3 The cell placement pattern and the short-circuiting method between adjacent cells shown can easily realize the sequential series connection of multiple cells and save wiring harness costs.

[0043] Furthermore, the first polarity pole of each battery cell is coupled to one of the battery monitoring chips AFE1 and AFE2, and the second polarity pole is coupled to the other of the battery monitoring chips AFE1 and AFE2. Furthermore, the poles of the same polarity in each battery cell are directly connected to the battery monitoring chip on the side closest to the pole.

[0044] Specifically, in an embodiment of the present invention, two battery monitoring chips AFE2 and AFE1 are respectively placed on the left and right sides of 12 battery cells arranged in parallel laterally, and are substantially perpendicular to the 12 battery cells to facilitate wiring. The positive poles of battery cells Cell1, Cell3, Cell5, Cell7, Cell9, and Cell11 are directly connected to the battery monitoring chip AFE1, and the negative poles are respectively connected to the positive poles of adjacent battery cells Cell2, Cell4, Cell6, Cell8, Cell10, and Cell12 through wiring harnesses. Then, the positive poles of battery cells Cell2, Cell4, Cell6, Cell8, Cell10, and Cell12 are directly connected to the battery monitoring chip AFE2, thereby coupling the negative poles of battery cells Cell1, Cell3, Cell5, Cell7, Cell9, and Cell11 to the battery monitoring chip AFE2.

[0045] The positive poles of cells Cell2, Cell 4, Cell 6, Cell 8, Cell 10 and Cell 12 are directly connected to the battery monitoring chip AFE2, and the negative poles of cells Cell2, Cell 4, Cell 6, Cell 8 and Cell 10 are respectively connected to the positive poles of adjacent cells Cell3, Cell 5, Cell 7, Cell 9 and Cell 11 through wiring harnesses, and then the positive poles of cells Cell 3, Cell 5, Cell 7, Cell 9 and Cell 11 are directly connected to the battery monitoring chip AFE1, thereby connecting cells Cell2, Cell 4, Cell 5, Cell 6, Cell 8 and Cell The negative pole of 10 is coupled to the battery monitoring chip AFE1, and the negative pole of cell Cell12 is directly connected to the battery monitoring chip AFE1, and is also connected to the battery monitoring chip AFE2 through a wiring harness, so that the last sampling channel of the battery monitoring chip AFE2 can directly sample the voltage of cell Cell12 (the last cell).

[0046] In the embodiment of the present invention, since there are a total of 12 battery cells, the total number of voltage sampling channels in the two battery monitoring chips AFE1 and AFE2 also needs to be 12. Preferably, when the number of the plurality of battery cells is an even number, the number of voltage sampling channels in each battery monitoring chip is half the number of the plurality of battery cells. Therefore, in a preferred embodiment, the number of voltage sampling channels in the two battery monitoring chips AFE1 and AFE2 is 6, and since two adjacent voltage sampling pins constitute one voltage sampling channel, the number of voltage sampling pins in each battery monitoring chip AFE1 and AFE2 is 7.

[0047] Continue to refer Figure 3 In the battery monitoring chip AFE1, the voltage sampling pin VS1 and the voltage sampling pin VS2 constitute the voltage sampling channel CH1, the voltage sampling pin VS2 and the voltage sampling pin VS3 constitute the voltage sampling channel CH2, the voltage sampling pin VS3 and the voltage sampling pin VS4 constitute the voltage sampling channel CH3, and so on, which are not listed one by one here; the voltage sampling channels in the battery monitoring chip AFE2 are set the same as the voltage sampling channels in the battery monitoring chip AFE1, and are not repeated here.

[0048] In addition, when the number of multiple battery cells is an odd number, preferably, the difference between the number of voltage sampling channels of the two battery monitoring chips is 1. For example, if the number of battery cells in this embodiment is reduced from 12 to 11, the sum of the number of voltage sampling channels of the two battery monitoring chips AFE1 and AFE2 is 11, and the difference in number is 1. In a preferred embodiment, the battery monitoring chip AFE1 has 6 sampling channels, and the number of its voltage sampling pins remains unchanged, and the battery monitoring chip AFE2 has 5 sampling channels, which does not require the voltage sampling pin VS7. In terms of the specific connection method of the 11 battery cells and the two battery monitoring chips AFE1 and AFE2, it is only necessary to directly connect the negative pole of the battery cell Cell11 to the voltage sampling pin VS6 of the battery monitoring chip AFE1, and connect the negative pole of the battery cell Cell11 to the voltage sampling pin VS7 of the battery monitoring chip AFE1 through a wiring harness. The connection method of other battery cells does not need to be changed.

[0049] Figure 4 Schematic diagram of a voltage sampling method for a battery module according to an embodiment of the present invention. Figure 4 , a single voltage sampling channel of the battery monitoring chip of the embodiment of the present invention can sample the voltage of two battery cells connected in series, and the last battery cell (Cell12) is connected to a single voltage sampling channel of the battery monitoring chip. Specifically, the voltage sampled by the voltage sampling channel CH1 in the battery monitoring chip AFE1 is V1=V Cell1 +V Cell2 The voltage sampled by the voltage sampling channel CH1 in the battery monitoring chip AFE2 is V2 = V Cell2 +V Cell3 The voltage sampled by the voltage sampling channel CH2 in the battery monitoring chip AFE1 is V3 = V Cell3 +V Cell4 The voltage sampled by the voltage sampling channel CH2 in the battery monitoring chip AFE2 is V4 = V Cell4 +V Cell5 , so the two battery monitoring chips AFE1 and AFE2 alternately sample and obtain the voltage: V5 = V Cell5 +V Cell6 、V6=V Cell6 +V Cell7 、V7=V Cell7 +V Cell8 、V8=V Cell8 +V Cell9 、V9=V Cell9 +V Cell10 、V 10 =V Cell10 +V Cell11 、V 11 =V Cell11 +VCel12 、V 12 =V Cell12 Then, the battery module calculates the voltage of each battery cell based on the sampling results of all voltage sampling channels of the two battery monitoring chips AFE1 and AFE2.

[0050] The battery module obtains the voltage value of each cell through mathematical calculations one by one. The algorithm is as follows:

[0051] V Cell12 =V 12 ; V Cell11 =V 11 -V Cell12 ; V Cell10 =V 10 -V Cell11 ; V Cell9 =V9-V Cell10 ;

[0052] V Cell8 =V8-V Cell9 ; V Cell7 =V7-V Cell8 ; V Cell6 =V6-V Cell7 ; V Cell5 =V5-V Cell6 ; V Cell4 =V4-V Cell5 ; V Cell3 =V3-V Cell4 ; V Cell2 =V2-V Cell3 ; V Cell1 =V1-V Cell2 ;

[0053] In this way, the two battery monitoring chips can accurately obtain the voltage information of each battery cell, and then realize real-time monitoring of the voltage of the battery module to perform voltage balancing and other controls.

[0054] It can be seen that the battery module of the present invention uses two battery monitoring chips to jointly monitor the voltages of multiple battery cells connected in series, and the pole of the first polarity of each battery cell is coupled to one of the two battery monitoring chips, and the pole of the second polarity is coupled to one of the two battery monitoring chips, so as to jointly calculate the voltage information of each battery cell based on the voltage sampling results of the two battery monitoring chips. The battery module structure of the present invention can greatly reduce the cost of the voltage sampling harness of the battery module based on the blade cell, because the pole of each battery cell only needs to be connected to the battery monitoring chip on the side close to the pole, or to the pole of the adjacent battery cell on the same side as the pole, and can also reduce the difficulty of wiring and solve the risk of leakage.

[0055] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A battery module, characterized in that: include: A plurality of battery cells connected in series; Two battery monitoring chips are used to jointly monitor the voltages of the multiple battery cells, wherein the first polarity pole of each battery cell is coupled to one of the two battery monitoring chips, and the second polarity pole is coupled to the other of the two battery monitoring chips.

2. The battery module according to claim 1, wherein: The multiple battery cells are arranged in parallel in a transverse direction, and poles of the same polarity of two adjacent battery cells are not located on the same side.

3. The battery module according to claim 2, characterized in that: The battery monitoring chip is placed on both sides of the multiple battery cells arranged in parallel in the transverse direction and is placed substantially perpendicular to the multiple battery cells.

4. The battery module according to claim 2, wherein: The positive electrode of the (n+1)th battery cell and the negative electrode of the (n)th battery cell are short-circuited by a wiring harness on the same side of the multiple battery cells arranged in parallel laterally, where n is a natural number greater than 0 and less than the number of battery cells.

5. The battery module according to claim 1, wherein: The poles of the battery cells are directly connected to the battery monitoring chip, or are connected to the battery monitoring chip through poles of different polarities of adjacent battery cells.

6. The battery module according to claim 1, characterized in that: Each of the battery monitoring chips has multiple voltage sampling pins, and two adjacent voltage sampling pins constitute a voltage sampling channel. Except for one voltage sampling channel in the two battery monitoring chips that samples the voltage of the first or last battery cell, each of the remaining voltage sampling channels samples the sum of the voltages of two adjacent battery cells.

7. The battery module according to claim 6, characterized in that: The sum of the numbers of the voltage sampling channels of the two battery monitoring chips is equal to the number of the battery cells.

8. The battery module according to claim 6, characterized in that: When the number of the plurality of battery cells is an even number, the number of voltage sampling channels of each battery monitoring chip is half the number of the battery cells.

9. The battery module according to claim 7, characterized in that: When the number of the plurality of battery cells is an odd number, the difference between the numbers of the voltage sampling channels of the two battery monitoring chips is 1.

10. The battery module according to claim 6, wherein: The two battery monitoring chips sequentially and alternately sample the voltage sum of the i-th and i+1-th battery cells, where i is a natural number greater than 0 and not greater than the difference between the number of battery cells and 1.

11. The battery module according to claim 10, characterized in that: The voltage of each battery cell is calculated based on the sampling results of all voltage sampling channels of the two battery monitoring chips.

12. A battery box, characterized in that: include: A battery module according to any one of claims 1 to 11.

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