Sampling device, battery management system and battery pack

Abstract

The invention relates to a battery, particularly provides a sampling device, a battery management system and a battery pack, and aims to solve the problem that an existing sampling device occupies a large space. In order to achieve the purpose, the sampling device comprises a circuit board and a sampling terminal, and the circuit board is arranged on the outer side edge of a battery pack; the first end of the sampling terminal is electrically connected with the cylindrical cell, and the second end is electrically connected with the circuit board. According to the battery pack, the circuit board arranged on the outer side edge of the side plate does not occupy extra space of the battery pack, and meanwhile, the battery pack can use a space for arranging a sampling device in the prior art for placing a battery cell, so that the energy density of the battery pack is improved. Meanwhile, circuit elements on the outer side edge of the fixing shell are few, the possibility that the circuit board is interfered is low, absorbent cotton and the like are generally arranged in the battery pack, and the possibility that the circuit board is affected with damp is low. And moreover, when the circuit board is arranged on the outer side edge of the side plate, the distance between the circuit board and the battery cell is relatively short, so that a sampling terminal can be conveniently arranged.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and specifically provides a sampling device, a battery management system and a battery pack. Background Art

[0002] At present, electric vehicles have become the key direction of future vehicle development. Battery packs are an important component of electric vehicles, and the management of battery packs is achieved through battery management systems.

[0003] In known battery packs, the sampling device occupies a large space, which affects the power density of the battery pack.

[0004] Therefore, there is an urgent need for a sampling device, a battery management system and a battery pack to solve the problem that the existing sampling devices occupy a large space. Summary of the invention

[0005] The present invention aims to solve the above technical problem, that is, to solve the problem that the existing sampling device occupies a large space.

[0006] In a first aspect, the present invention provides a sampling device for collecting status information of cylindrical cells in a battery pack, the sampling device comprising: a circuit board, arranged on the outer side of the battery pack; a sampling terminal, a first end of the sampling terminal is electrically connected to the cylindrical cell, and a second end is electrically connected to the circuit board.

[0007] In a specific implementation of the above sampling device, the angle between the plane of the circuit board and the plane where the first end is located ranges from 85° to 95°.

[0008] In a specific embodiment of the sampling device, the plurality of cylindrical cells in the battery pack are arranged vertically, and the electrodes of the cylindrical cells are disposed on the upper surfaces of the cylindrical cells; and the first end is electrically connected to the electrodes of the cylindrical cells.

[0009] In a specific embodiment of the sampling device, a side plate is provided on the side of the battery pack, and the circuit board is attached to the side of the side plate facing away from the cylindrical battery cell.

[0010] In a specific implementation of the sampling device, a positioning hole is provided on the side plate, a positioning piece is provided on the sampling device, the positioning piece is connected to the circuit board, and the positioning piece is plugged into the positioning hole.

[0011] In a specific implementation of the above sampling device, the sampling terminal is a nickel sheet.

[0012] In a specific embodiment of the above-mentioned sampling device, the sampling terminal is provided with a buffer zone, the first end and the second end generate deformation displacement through the buffer zone, and the maximum deformation displacement between the first end and the second end is greater than or equal to the displacement of the circuit board relative to the battery pack.

[0013] In a specific embodiment of the above sampling device, the sampling device further comprises a temperature sampling component, which is welded or plugged into the circuit board, and one end of the temperature sampling component facing away from the circuit board faces the cylindrical battery cell.

[0014] In a specific embodiment of the sampling device, the side plate is provided with a through hole, and the end of the temperature sampling member facing away from the circuit board passes through the through hole and is attached to the cylindrical battery core.

[0015] In a specific implementation of the sampling device, the side plate is provided with a through hole, the through hole is filled with a heat-conducting material, and the temperature sampling member is in contact with the heat-conducting material.

[0016] In a second aspect, the present invention provides a battery management system, comprising: a battery management controller; and the above-mentioned sampling device, wherein the sampling device is electrically connected to the battery management controller.

[0017] In a third aspect, the present invention provides a battery pack, comprising: a battery group, which includes a cylindrical battery cell and a fixed shell, wherein the cylindrical battery cell is fixed in the fixed shell; the above-mentioned sampling device, wherein the circuit board is arranged on the outer side of the fixed shell.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The sampling device provided by the present invention includes a circuit board and a sampling terminal. The circuit board is arranged on the outer side of the battery pack; the first end of the sampling terminal is electrically connected to the cylindrical battery cell, and the second end is electrically connected to the circuit board. In the battery pack, since there is a certain gap between adjacent battery packs, the circuit board arranged on the outer side of the side panel will not occupy additional space in the battery pack, and will not reduce the energy density of the battery pack. At the same time, the battery pack provided by the present invention can use the space used to set the sampling device in the known technology to place the battery cell to improve the energy density of the battery pack. At the same time, there are fewer circuit elements on the outer side of the fixed shell, and the possibility of the circuit board being disturbed is lower. In addition, absorbent cotton and the like are generally arranged in the battery pack, and the possibility of the circuit board being damp is lower. In addition, when the circuit board is arranged on the outer side of the side panel, the distance between the circuit board and the battery cell is closer, which can facilitate the arrangement of the sampling terminal.

[0020] Furthermore, the sampling terminal is provided with a buffer zone, and the first end and the second end are deformed and displaced through the buffer zone, and the maximum deformation displacement between the first end and the second end is greater than or equal to the displacement of the circuit board relative to the battery pack. When the battery pack or battery pack is impacted and vibrates, the nickel sheet of the buffer zone can be deformed to form a deformation displacement between the first end and the second end of the sampling terminal, and at the same time, the circuit board and the battery pack will also generate impact displacement. If the maximum deformation displacement between the first end and the second end is greater than or equal to the displacement of the circuit board relative to the battery pack, the stress inside the sampling terminal can be eliminated, reducing the pulling force of the sampling terminal on the battery cell and the circuit board, thereby reducing the possibility of desoldering of the sampling terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0022] Figure 1 The battery pack provided by the present invention is connected in parallel.

[0023] Figure 2 The method of connecting the cells of the battery pack provided by the present invention in series;

[0024] Figure 3 is a schematic structural diagram of a battery pack provided by the present invention;

[0025] Figure 4 It is an example of a temperature sampling component in a battery pack provided by the present invention;

[0026] Figure 5 are structural diagrams of some examples of sampling devices provided by the present invention;

[0027] Figure 6 is a schematic diagram of the structure of the sampling terminal provided by the present invention;

[0028] Figure 7 are structural diagrams of other examples of sampling devices provided by the present invention;

[0029] Figure 8 are structural diagrams of some further examples of sampling devices provided by the present invention;

[0030] Fig. 9 It is a structural diagram of some other examples of sampling devices provided by the present invention.

[0031] Description of reference numerals:

[0032] 1. Battery cell; 2. Circuit board; 21. First board; 22. Second board; 23. Transmission line; 3. Bus; 4. Sampling chip; 5. Sampling terminal; 51. First side; 511. First welding area; 52. Second side; 521. Second welding area; 53. Buffer; 6. Daisy chain; 7. Fixed shell; 71. Bottom plate; 72. Side plate; 721. Positioning hole; 722. Through hole; 8. Positioning piece; 9. Temperature sampling piece. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0034] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0035] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "setting", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate medium, or the internal connection of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the known technology, for a battery pack adopting a CTP (Cell to Pack) structure, the battery pack includes multiple battery packs and a box body, and the multiple battery packs are installed in the box body, and there is a certain gap between adjacent battery packs. The space at the front end of the box body near the side wall of the box body is the front compartment, which is mainly used to set up electronic control components and cooling pipes.

[0037] The battery management system includes a battery management controller and multiple battery supervision circuits (CSCs). Each battery pack is equipped with a battery monitoring unit to monitor the status information of the battery cell 1. The status information of the battery cell 1 includes but is not limited to the voltage. The status information of the battery cell monitored by the battery monitoring unit is uploaded to the battery management controller through the bus for processing and analysis, and the battery pack is comprehensively managed. Specifically, each battery pack is equipped with a battery monitoring unit, and several battery monitoring units form a slave battery management unit (SBMU). According to the needs of energy storage capacity, an appropriate number of SBMUs form a master battery management unit (MBMU), and are equipped with other required modules such as local monitoring systems, high-voltage detection and insulation monitoring modules. These modules together constitute a battery management system (BMS).

[0038] In the known technology, the sampling device is centrally arranged in the front compartment of the battery pack. In order to prevent the circuit boards from getting damp or interfering with each other, a shell is provided on the outside of the sampling device, resulting in the sampling device occupying a larger space, which affects the power density of the battery pack.

[0039] In order to solve the above problems, the present invention provides a battery pack, which includes a sampling device and a battery pack.

[0040] Figure 1 This is the method of connecting the cells of the battery pack in parallel provided by the present invention. Figure 2 This is the method of connecting the cells of the battery pack provided by the present invention in series.

[0041] like Figure 1 and Figure 2 As shown, each battery pack includes a plurality of battery cells 1 and a fixing shell 7 , and all the battery cells 1 are fixed by the fixing shell 7 to keep the battery cells 1 stable.

[0042] In the example of the present invention, the battery cell 1 is a cylindrical battery cell. The multiple battery cells 1 in the battery pack are arranged vertically, and the electrodes of the battery cells 1 are arranged on the upper surface and the lower surface of the battery cells 1, wherein the positive electrode of the battery cell 1 is located on the upper surface of the battery cell 1, and the negative electrode is located on the lower surface of the battery cell 1.

[0043] Multiple cells 1 in a single battery pack are first connected in parallel to form parallel segments, and then multiple parallel segments are connected in series to make the battery pack have a stable voltage. A bus 3 is set between adjacent parallel segments of cells 1 in the battery pack, and the first end of the bus 3 is connected to the positive electrode of one cell 1, and the second end of the bus 3 is connected to the negative electrode of the adjacent cell 1. Through multiple bus bars 3, the parallel segments of multiple cells 1 can be connected in series. Taking a cylindrical cell as an example, assuming that the voltage of the cylindrical cell is 3.7V, the voltage of each parallel segment is 3.7V. If the number of parallel segments in series in the battery pack is 33, the voltage of the battery pack is 122.1V. The more parallel segments in series in the battery pack, the greater the voltage of the battery pack.

[0044] Figure 3 It is a structural schematic diagram of the battery pack provided by the present invention.

[0045] like Figure 3 As shown, the fixed shell 7 includes a bottom plate 71 and a side plate 72, and the side plate 72 is protrudingly arranged on a side surface of the bottom plate 71. All the battery cells 1 are fixedly arranged in the area surrounded by the bottom plate 71 and the side plate 72 to keep the battery cells 1 in a stable state.

[0046] Figure 5 These are structural diagrams of some examples of sampling devices provided by the present invention.

[0047] like Figure 3 and Figure 5 As shown, the sampling device includes a circuit board 2, a sampling chip 4 and a sampling terminal 5, and the sampling chip 4 is arranged on the circuit board 2 and electrically connected to the circuit board 2. There are multiple sampling terminals 5, and the first end of each sampling terminal 5 is electrically connected to the electrode of the battery cell 1, specifically welded to the bus 3 to achieve electrical connection with the electrode of the battery cell 1; the second end of the sampling terminal 5 is electrically connected to the circuit board 2. The voltage collected by the first end of the sampling terminal 5 is the voltage of a parallel segment of the battery cell 1. The status information of the battery cell 1 is transmitted to the sampling chip 4 through the sampling terminal 5 and the circuit board 2 in turn, and then processed by the sampling chip 4 and uploaded to the battery management controller. In a specific example of the present invention, the sampling chip 4 is an analog sampling terminal AFE (Analog Front End), which is mainly used to convert the analog signal of the collected battery cell 1 status information into a digital signal and upload it.

[0048] Among them, Figure 3 As shown, the circuit board 2 is fitted on the side of the side plate 72 away from the battery cell 1. The side plate 72 is provided with a positioning hole 721, and the sampling device is provided with a positioning member 8. The positioning member 8 is connected to the circuit board 2 and inserted into the positioning hole 721 to position or fix the circuit board 2 and the side plate 72.

[0049] In the battery pack, since there is a certain gap between adjacent battery groups, the circuit board 2 arranged on the outer side of the side panel 72 will not occupy additional space in the battery pack, and will not reduce the energy density of the battery pack. At the same time, the battery pack provided by the present invention can use the space used for setting the sampling device in the known technology to place the battery cell 1 to improve the energy density of the battery pack. At the same time, there are fewer circuit elements on the outer side of the fixed shell 7, and the possibility of the circuit board 2 being disturbed is lower. In addition, absorbent cotton and the like are generally provided in the battery pack, and the possibility of the circuit board 2 being damp is lower. Therefore, the circuit board 2 can be exposed (that is, no protective shell is provided) to further reduce the space occupied by the sampling device. In addition, when the circuit board 2 is provided on the outer side of the side panel 72, the distance between the circuit board 2 and the battery cell 1 is closer, so the sampling terminal 5 can be conveniently provided.

[0050] like Figure 3 As shown, in some embodiments, the sampling device also includes a temperature sampling component 9, which is electrically connected to the circuit board 2. Specifically, the temperature sampling component 9 is welded or plugged into the circuit board 2. The temperature sampling component 9 can collect the temperature information of the battery cell 1, and transmit the temperature information to the signal processing chip via the circuit board 2, and convert the temperature information into digital information. The signal processing chip can be arranged on the circuit board 2, or on other circuit modules. When the signal processing chip is arranged on the circuit board 2, it can be a sampling chip 4 or other processing chips.

[0051] In a possible embodiment, the temperature sampling component 9 is of a patch type, and the patch type temperature sampling component 9 is directly welded to the circuit board 2, and the temperature sampling component 9 is affixed near the circuit board 2. A through hole 722 is provided on the side plate 72, and the through hole 722 passes through the side plate 72 to connect the battery cell side and the circuit board side. The through hole 722 is filled with a thermally conductive material, such as a thermally conductive adhesive, and the temperature sampling component 9 is in contact with the thermally conductive material. The temperature of the battery cell 1 can be transferred to the patch type temperature sampling component 9 through the thermally conductive material, so that the temperature information of the battery cell 1 collected by the patch type temperature sampling component 9 is more accurate.

[0052] Figure 4 It is an example of the temperature sampling component in the battery pack provided by the present invention.

[0053] In another possible implementation, Figure 4As shown, the temperature sampling component 9 is of a wiring harness type or a plug-in type. Among them, the wiring harness type temperature sampling component 9 is welded or plugged with the circuit board 2 through a flexible circuit board to achieve electrical connection, and the plug-in type temperature sampling component 9 is plugged with the circuit board 2 through a slot to achieve electrical connection. Both the wiring harness type and the plug-in type temperature sampling component 9 have a certain length. A through hole 722 is provided on the side plate 72, and the through hole 722 passes through the side plate 72 to connect the battery cell side and the circuit board side. The end of the wiring harness type and the plug-in type temperature sampling component 9 facing away from the circuit board 2 passes through the through hole 722 and is attached to the outer surface of the battery cell 1, so as to directly obtain the temperature information of the battery cell 1.

[0054] Figure 6 It is a structural schematic diagram of the sampling terminal provided by the present invention.

[0055] Regarding sampling terminal 5, Figure 6 As shown, in some examples, the sampling terminal 5 is a nickel sheet. Since the distance between the circuit board 2 and the battery cell 1 is relatively short, it is possible to use the nickel sheet as the sampling terminal 5.

[0056] There is an angle between the plane of the circuit board 2 and the plane where the first end of the sampling terminal 5 is located, and the angle ranges from 85° to 95°, preferably 90°.

[0057] Specifically, the sampling terminal 5 has a first side 51 and a second side 52. The first end of the sampling terminal 5 is the end of the first side 51 away from the second side 52, also called the first welding area 511. The first welding area 511 is welded to the battery cell 1 or the bus 3, so that the first end of the sampling terminal 5 is electrically connected to the battery cell 1. The second end of the sampling terminal 5 is the end of the second side 52 away from the first side 51, also called the second welding area 521. The second welding area 521 is welded to the circuit board 2, so that the second end of the sampling terminal 5 is electrically connected to the circuit board 2. The second side 52 is generally arranged parallel to the circuit board 2 to facilitate welding the second side 52 to the circuit board 2. The plane where the first end of the sampling terminal 5 is located is the plane where the first side 51 is located, and the plane where the circuit board 2 is located is the plane where the second side 52 is located. Therefore, the angle between the plane of the circuit board 2 and the plane where the first end of the sampling terminal 5 is located is the angle between the first side 51 and the second side 52.

[0058] Furthermore, the sampling terminal 5 is provided with a buffer zone 53, specifically, the buffer zone 53 is provided on the first side 51. The buffer zone 53 is a nickel sheet in a zigzag or wavy shape, and the nickel sheet of the buffer zone 53 has a certain elasticity and can be deformed to form a deformation displacement between the first end and the second end of the sampling terminal 5. When the battery pack or battery group is impacted and vibrates, the nickel sheet of the buffer zone 53 can be deformed to form a deformation displacement between the first end and the second end of the sampling terminal 5, and at the same time, the circuit board 2 will also generate an impact displacement with the battery pack. If the maximum deformation displacement between the first end and the second end is greater than or equal to the displacement of the circuit board 2 relative to the battery pack, the stress inside the sampling terminal 5 can be eliminated, and the pulling force of the sampling terminal 5 on the battery cell 1 and the circuit board 2 can be reduced, thereby reducing the possibility of desoldering of the sampling terminal 5.

[0059] It should be noted that although the buffer zone 53 is set on the first side 51 in the example of the present invention, this is not a specific limitation of the present invention. Without departing from the principle of the present invention, in other embodiments, those skilled in the art may also set the buffer zone 53 on the second side 52, or set it on both the first side 51 and the second side 52.

[0060] Regarding the sampling terminal 5, in some other examples, the sampling terminal 5 includes a first connecting line and a first connector, and the first connecting line includes two. One end of one first connecting line is electrically connected to the first connector, and the other end is electrically connected to the battery cell 1. One end of another first connecting line is electrically connected to the first connector, and the other end is electrically connected to the circuit board 2. The first connecting line can be a wiring harness or a flexible circuit board. The flexible circuit can be an FPC (Flexible Printed Circuit) flexible etching circuit, or an FDC (Flexible Die-cutting Circuit) flexible die-cutting circuit.

[0061] The first connector is also called a connector, including a plug and a socket, which can be plugged into each other to achieve electrical connection. The plug and the socket are electrically connected to a first connecting line respectively, and then the plug and the socket of the first connector are plugged into each other to achieve electrical connection between the two first connecting lines.

[0062] Regarding the sampling terminal 5 , in some other examples, the sampling terminal 5 includes a first connecting wire, and two ends of the first connecting wire are electrically connected to the battery cell 1 and the circuit board 2 respectively.

[0063] Regarding the setting of circuit board 2, Figure 5As shown, in some examples, the circuit board 2 includes a plurality of first boards 21, each of which is provided with a sampling chip 4, and each of which is connected to a small number of sampling terminals 5, thereby reducing the length of each first board 21, so that the first board 21 is not prone to the problem of high stress due to its long length when using a printed circuit board. Of course, in other embodiments, all of the first boards 21 may be made of flexible circuit boards, or part of the first boards 21 may be made of flexible circuit boards, and the other part of the first boards 21 may be made of printed circuit boards.

[0064] Figure 7 2 are structural diagrams of other examples of the sampling device provided by the present invention.

[0065] Regarding the setting of circuit board 2, Figure 7 As shown, in other examples, the circuit board 2 includes a first board 21 and a second board 22, and a transmission line 23 is arranged between the first board 21 and the second board 22 for signal transmission. Each first board 21 is connected to at least one second board 22. The sampling chip 4 is arranged on the first board 21 and electrically connected to the first board 21, and the sampling chip 4 is specifically connected to the first board 21 by soldering. By dividing the circuit board 2 into the first board 21 and the second board 22, the length of the single circuit board 2 can be effectively reduced. At the same time, the second board 22 is an extension of the first board 21, and the state information of the battery cell 1 connected to the second board 22 can be transmitted to the first board 21 via the transmission line 23, so that the number of sampling terminals 5 connected to the first board 21 and the second board 22 is as equal to the number of sampling channels of the sampling chip 4 as possible, so that the efficiency of the sampling chip 4 is maximized, thereby reducing the number of sampling chips 4 used to save costs. Of course, in most cases, the number of sampling channels of the sampling chip 4 cannot be fully utilized, and the number of sampling terminals 5 connected to the first board 21 and the second board 22 can be slightly less than the number of sampling channels of the sampling chip 4.

[0066] Figure 8 It is a structural diagram of some further examples of sampling devices provided by the present invention.

[0067] Regarding the setting of circuit board 2, Figure 8 As shown, in some other examples, one first board 21 is connected to two second boards 22. Of course, this is not a specific limitation of the present invention. Without departing from the principle of the present invention, in other examples, each first board 21 may be connected to more than two second boards 22. Generally speaking, each first board 21 is connected to two second boards 22, and the two second boards 22 are respectively located on both sides of the first board 21, which is conducive to wiring to prevent the lines from crossing each other.

[0068] like Figure 7As shown, regarding the arrangement of the sampling chip 4, in some examples, the number of sampling chips 4 arranged on the first board 21 is one. This arrangement can easily make the number of sampling terminals 5 connected to the first board 21 and the second board 22 equal to the number of sampling channels of the sampling chip 4.

[0069] like Figure 8 As shown, regarding the arrangement of the sampling chip 4, in other examples, the number of sampling chips 4 arranged on the first board 21 is two or more. If the number of sampling chips 4 arranged on the first board 21 is two or more, under the premise that the sampling channels of the sampling chip 4 correspond one-to-one to the battery cells 1, the more battery cells 1 each first board 21 can collect state parameters, the fewer the number of first boards 21 can be arranged. Since the manufacturing process of the first board 21 is relatively complex and its manufacturing cost is relatively high, reducing the number of first boards 21 can further reduce the cost of the sampling device.

[0070] Regarding the connection position of the sampling terminal 5, Figure 8 As shown, in some examples, the first board 21 and the second board 22 are both connected to the sampling terminal 5. One end of the sampling terminal 5 is electrically connected to the battery cell 1, and the end of some sampling terminals 5 away from the battery cell 1 is electrically connected to the first board 21, and the end of another part of the sampling terminals 5 away from the battery cell 1 is connected to the second board 22. The voltage signals of some of the battery cells 1 are sequentially transmitted to the sampling chip 4 through the sampling terminal 5, the second board 22, the transmission line 23 and the first board 21, and the voltage signals of another part of the battery cells 1 are sequentially transmitted to the sampling chip 4 through the sampling terminal 5 and the first board 21.

[0071] Fig. 9 It is a structural diagram of some other examples of sampling devices provided by the present invention.

[0072] Regarding the connection position of the sampling terminal 5, Fig. 9 As shown, in other examples, the sampling terminal 5 is only connected to the second board 22. One end of the sampling terminal 5 is electrically connected to the battery cell 1, and the other end is electrically connected to the second board 22. The voltage signal of the battery cell 1 is transmitted to the sampling chip 4 through the sampling terminal 5, the second board 22, the transmission line 23 and the first board 21 in sequence. Since the sampling chip 4 is arranged on the first board 21, the circuit will be slightly complicated. Not arranging the sampling terminal 5 on the first board 21 can reduce the setting length of the first board 21 to further reduce the stress of the first board 21.

[0073] Regarding the materials of the first plate 21 and the second plate 22, in some examples, the first plate 21 and the second plate 22 are both printed circuit boards to reduce the cost of the sampling device. When the sampling terminal 5 is made of a nickel sheet, the connection between the sampling terminal 5 and the first plate 21 and the second plate 22 is relatively simple and reliable. At the same time, when the second plate 22 is made of a printed circuit board, the sampling chip 4 can be directly welded.

[0074] Regarding the materials of the first board 21 and the second board 22, in some other examples, the first board 21 is a printed circuit board and the second board 22 is a flexible circuit board. Due to its own characteristics, the stress of the flexible circuit board is small and the length can be set longer, so that the second board 22 can be connected to more cells 1 through the sampling terminal 5. When the second board 22 is a flexible circuit board, the sampling terminal 5 can be a lead-out portion from the second board 22. The lead-out portion of the sampling terminal 5 inside the second board 22 can include: copper foil, aluminum foil, copper-nickel strip, aluminum-nickel strip, or nickel strip.

[0075] Regarding the materials of the first plate 21 and the second plate 22, in some other examples, the first plate 21 is a flexible circuit board, and the second plate 22 is a flexible circuit board or a printed circuit board. When the first plate 21 is a flexible circuit board, the portion of the first plate 21 where the sampling chip 4 is arranged needs to be hardened to facilitate welding of the sampling chip 4.

[0076] Regarding the transmission line 23, in some examples, the transmission line 23 includes a connecting line, and both ends of the connecting line are electrically connected to the first board 21 and the second board 22 respectively, which can be specifically plugged or welded. The connecting line can be a wire harness or a flexible line.

[0077] Regarding the transmission line 23, in some other examples, the transmission line 23 includes a second connector and a second connecting wire, and at least one end of some of the second connecting wires is electrically connected to the second connector, and the other end is electrically connected to the first board 21 or the second board 22, so as to establish circuit communication between the first board 21 and the second board 22. Specifically, when the number of second connectors is single, one end of all second connecting wires is electrically connected to the second connector, and the other end is electrically connected to the first board 21 or the second board 22; when there are multiple second connectors, at least one end of the second connecting wire is electrically connected to the first board 21 and the other end is electrically connected to a second connector, at least one end of the second connecting wire is electrically connected to the second board 22 and the other end is electrically connected to a second connector, and both ends of the remaining second connecting wires are electrically connected to different second connectors. The form of electrical connection can be welding or plug-in. The second connecting wire can be a wiring harness or a flexible circuit. The structure of the second connector is the same as that of the first connector.

[0078] A daisy chain 6 is also provided between the first board 21 and the second board 22 for communication. The two ends of the daisy chain 6 are electrically connected to the first board 21 and the second board 22 respectively. The purpose of the first board 21 and the second board 22 communicating through the daisy chain 6 is to isolate the mutual interference between the high-voltage side and the low-voltage side. The high-voltage side refers to the collected voltage signal of the battery cell 1, and the low-voltage side refers to the low-voltage signal processed by the sampling chip 4.

[0079] Based on the above-mentioned sampling device, the present invention also provides a battery management system, which includes a battery management controller and the above-mentioned sampling device. The sampling device is electrically connected to the battery management controller, and can collect and process the status information of the battery cell 1 and upload it to the battery management controller for further processing and analysis, so as to facilitate comprehensive management of the battery pack.

[0080] Based on the above sampling device, the present invention further provides a battery pack, which includes the above sampling device and the above battery pack, and the circuit board 2 is arranged on the outer side of the side plate 72 away from the battery cell 1.

[0081] In summary, the advantages of the battery pack provided by the present invention are as follows:

[0082] The circuit board 2 is fitted on the side of the side panel 72 away from the battery cell 1. In the battery pack, since there is a certain gap between adjacent battery packs, the circuit board 2 arranged on the outer side of the side panel 72 will not occupy additional space in the battery pack, and will not reduce the energy density of the battery pack. At the same time, the battery pack provided by the present invention can use the space used for setting the sampling device in the known technology to place the battery cell 1 to improve the energy density of the battery pack. At the same time, there are fewer circuit elements on the outer side of the fixed shell 7, and the possibility of the circuit board 2 being disturbed is low. In addition, absorbent cotton and the like are generally provided in the battery pack, and the possibility of the circuit board 2 being damp is low. Therefore, the circuit board 2 can be exposed to further reduce the space occupied by the sampling device. In addition, when the circuit board 2 is arranged on the outer side of the side panel 72, the distance between the circuit board 2 and the battery cell 1 is close, which can facilitate the arrangement of the sampling terminal 5.

[0083] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A sampling device for collecting status information of a cylindrical battery cell (1) in a battery pack, characterized in that: The sampling device comprises: A circuit board (2) is arranged on the outer side of the battery pack; A sampling terminal (5), wherein a first end of the sampling terminal (5) is electrically connected to the cylindrical battery core (1), and a second end of the sampling terminal (5) is electrically connected to the circuit board (2).

2. The sampling device according to claim 1, characterized in that: The angle between the plane of the circuit board (2) and the plane where the first end is located ranges from 85° to 95°.

3. The sampling device according to claim 1 or 2, characterized in that: The plurality of cylindrical battery cells (1) in the battery pack are arranged vertically, and the electrodes of the cylindrical battery cells (1) are arranged on the upper surface of the cylindrical battery cells (1); The first end is electrically connected to an electrode of the cylindrical battery core (1).

4. The sampling device according to claim 1, characterized in that: A side plate (72) is provided on the side of the battery pack, and the circuit board (2) is attached to the side of the side plate (72) facing away from the cylindrical battery core (1).

5. The sampling device according to claim 4, characterized in that: The side plate (72) is provided with a positioning hole (721), the sampling device is provided with a positioning member (8), the positioning member (8) is connected to the circuit board (2), and the positioning member (8) is plugged into the positioning hole (721).

6. The sampling device according to claim 1, characterized in that: The sampling terminal (5) is a nickel sheet.

7. The sampling device according to claim 1, characterized in that: The sampling terminal (5) is provided with a buffer zone (53), the first end and the second end are deformed and displaced through the buffer zone (53), and the maximum deformation displacement between the first end and the second end is greater than or equal to the displacement of the circuit board (2) relative to the battery pack.

8. The sampling device according to claim 4, characterized in that: The sampling device further comprises a temperature sampling component (9), wherein the temperature sampling component (9) is welded or plugged into the circuit board (2), and an end of the temperature sampling component (9) facing away from the circuit board (2) faces the cylindrical battery core (1).

9. The sampling device according to claim 8, characterized in that: The side plate (72) is provided with a through hole (722), and the end of the temperature sampling component (9) facing away from the circuit board (2) passes through the through hole (722) and is then attached to the cylindrical battery core (1).

10. The sampling device according to claim 8, characterized in that: The side plate (72) is provided with a through hole (722), the through hole (722) is filled with a heat-conducting material, and the temperature sampling component (9) is in contact with the heat-conducting material.

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