Battery pack, battery device, electric equipment and energy storage device

Abstract

The utility model provides a battery pack, a battery device, electric equipment and an energy storage device, and belongs to the field of batteries. The battery pack comprises N single batteries which are connected in series, a sampling chip, N sampling loops and a clamping circuit, and the total positive end of the sampling chip is connected with a power supply lead connected with the positive electrode of a target single battery, a collection lead connected with the positive electrode of the target single battery and the negative electrodes of two first protection diodes. The positive electrode of the first protection diode is grounded, the clamping circuit is also provided with a discharge circuit, the discharge circuit is provided with a discharge diode, and the acquisition lead connected with the positive electrode of each battery monomer except the target battery monomer is connected with the negative electrode of the first protection diode through the discharge circuit. The surge voltage appearing at the positive electrode of the target battery monomer is suppressed by the first protection diode, and the surge voltage appearing at the series connection position of the two battery monomers is guided to the first protection diode through the bleeder circuit to be suppressed, so that the risk that the sampling chip is directly impacted by the surge voltage to be damaged is reduced.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery pack, battery device, electrical equipment, and energy storage device. Background Technology

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0003] A key component of a battery system is the Battery Management System (BMS), which is responsible for monitoring and managing the battery's status. Specifically, the sampling chip within the BMS is responsible for monitoring battery information and is located at the very beginning of the battery information processing chain. During actual operation, if a surge occurs in the circuit between the battery pack, the load, and the power grid, the surge voltage will penetrate the battery pack. As the component in the BMS directly connected to the individual battery cells, the sampling chip will be the first to be affected, potentially leading to damage from the surge voltage. Utility Model Content

[0004] This application aims to at least solve one of the technical problems existing in the background art. To this end, one object of this application is to provide a battery pack, battery device, electrical equipment, and energy storage device that reduces the risk of damage to the sampling chip due to surge voltage impact and improves the operational stability and safety of the battery pack.

[0005] An embodiment of the first aspect of this application provides a battery pack, including N battery cells connected in series, a sampling chip, N sampling circuits, and a clamping circuit; the battery cell with the highest positive electrode potential among the N battery cells is the target battery cell; wherein, N is a positive integer greater than or equal to 2; the sampling chip has a total positive terminal, and the positive electrode of the target battery cell is electrically connected to the total positive terminal through a power supply lead; the N sampling circuits have N+1 acquisition leads, such that the positive and negative electrodes of each battery cell are coupled to the sampling chip through an acquisition lead; the acquisition lead connected to the positive electrode of the target battery cell is the target lead;

[0006] The clamping circuit includes a discharge circuit, two first protection diodes, and N-1 connection nodes. The anodes of the two first protection diodes are grounded, and the cathodes of the two first protection diodes are connected to the power supply lead and the target lead, respectively. The acquisition lead connected to the anode of each battery cell (excluding the target battery cell) is connected to the discharge circuit at a corresponding connection node. The first end of the discharge circuit is connected to either the power supply lead or the target lead. A discharge diode is provided between any connection node and the first end of the discharge circuit connected to it, with the cathode of the discharge diode close to the cathode of the first protection diode connected to it.

[0007] In the technical solution of this application embodiment, the battery pack is equipped with a clamping circuit, which includes two first protection diodes. The negative terminals of the two first protection diodes are respectively connected to the power supply lead and the target lead. Thus, when a surge voltage enters the battery pack, the surge voltage borne by the positive terminal of the target battery cell can be discharged through the first protection diodes, thereby protecting the overall positive terminal and a sampling terminal connected to the target lead from damage caused by the surge voltage. Thanks to the clamping circuit also including a discharge circuit, the surge voltage borne by the positive terminals of the remaining battery cells (excluding the target battery cell) is guided to the power supply lead or the target lead through the discharge circuit, allowing the surge voltage to be conducted to the first protection diodes for discharge.

[0008] This provides surge protection for each pin of the sampling chip, reducing the risk of damage to the sampling chip from surge voltage impacts and improving the operational stability and safety of the battery pack.

[0009] In some embodiments, the discharge circuit includes at least two discharge diodes connected in parallel. The positive terminal of one of the discharge diodes is grounded, and the negative terminal is connected to the positive terminal of the other discharge diode at a connection node. The negative terminal of the other discharge diode is close to the negative terminal of the first protection diode connected to it.

[0010] In this embodiment, the two discharge diodes connected in parallel constitute part of the discharge circuit. These two discharge diodes can provide discharge paths in different directions for the surge voltage between two adjacent battery cells.

[0011] In some embodiments, there are N-1 discharge circuits, and each of the N-1 discharge circuits corresponds to one of the N-1 battery cells other than the target battery cell.

[0012] By designing N-1 discharge circuits, each of the N-1 battery cells other than the target battery cell corresponds to a discharge circuit, so that when the positive terminal of the battery cell is subjected to a surge voltage impact, the surge voltage is guided to the first protection diode through the corresponding discharge circuit to achieve discharge.

[0013] In some embodiments, the discharge circuit includes N discharge diodes corresponding one-to-one with N battery cells. The positive and negative terminals of each discharge diode are respectively connected across the two acquisition leads of the sampling circuit where the corresponding battery cell is located, and the N discharge diodes are connected in sequence.

[0014] This embodiment uses only one discharge circuit, which simplifies the circuit design of the battery pack, reduces circuit complexity, and reduces the difficulty of circuit wiring and installation.

[0015] In some embodiments, the clamping circuit further includes a second protection diode, the positive terminal of which is grounded; either the power supply lead or the target lead is connected to the first terminal of the discharge circuit and also to the negative terminal of the second protection diode.

[0016] By designing a second protection diode, the surge voltage discharge is shared, thereby reducing the discharge burden on the first protection diode.

[0017] In some embodiments, the first protection diode is closer to the positive terminal of the target battery cell than the first terminal of the discharge circuit connected thereto, and the second protection diode is closer to the sampling chip than the first terminal of the discharge circuit connected thereto.

[0018] In this embodiment, the first terminal of the discharge circuit is located between the negative terminals of the first protection diode and the second protection diode, so that the surge voltage between two adjacent battery cells can be discharged quickly, which can further reduce the discharge burden of the first protection diode.

[0019] In some embodiments, a resistor is connected in series with the power supply lead and each acquisition lead.

[0020] By introducing a resistor, the surge voltage can be partially shared, thus positively impacting the surge protection of the sampling chip.

[0021] In some embodiments, the resistor on the acquisition lead is connected between the battery cell and the corresponding connection node.

[0022] This embodiment limits the resistor before the surge voltage between two adjacent battery cells is directed to the discharge circuit, thereby reducing the discharge burden on the discharge diode.

[0023] In some embodiments, the first protection diode is a transient voltage suppressor diode or a Zener diode; and / or, the discharge diode is any one of a Schottky diode, a silicon diode, and a germanium diode.

[0024] An embodiment of the second aspect of this application provides a battery device that includes the battery pack described in the above embodiments.

[0025] An embodiment of the third aspect of this application provides an electrical device that includes a battery pack as described in the above embodiments, the battery pack being used to provide electrical energy, or includes a battery device as described in the above embodiments, the battery device being used to provide electrical energy.

[0026] An embodiment of the fourth aspect of this application provides an energy storage device, which includes the battery pack or the battery device described in the above embodiments.

[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0028] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0029] Figure 1 Circuit diagrams of battery packs and sampling chips in some related technologies;

[0030] Figure 2 This is a schematic diagram of the vehicle structure according to some embodiments of this application;

[0031] Figure 3 This is an exploded view of the battery device according to some embodiments of this application;

[0032] Figure 4 This is a circuit diagram showing the relationship between the battery pack and the sampling chip in some embodiments of this application;

[0033] Figure 5 This is a circuit diagram showing the relationship between the battery pack and the sampling chip in some other embodiments of this application;

[0034] Figure 6 This is a circuit diagram of the battery pack and sampling chip in some embodiments of this application;

[0035] Figure 7 This is a circuit diagram of the battery pack and sampling chip in some embodiments of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1000 vehicles;

[0038] Battery unit 100, controller 200, motor 300;

[0039] Battery pack 10, battery cell 11, battery management system 2, sampling chip 21, MCU 22, sampling circuit 3, acquisition lead 31, power supply circuit 4, power supply lead 41, grounding lead 42, clamping circuit 5, discharge circuit 51, enclosure 6, first enclosure 61, second enclosure 62. Detailed Implementation

[0040] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0042] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0043] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0045] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0046] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0047] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "connection" and "electrical connection" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium, or the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0048] A surge, also known as a transient surge or spike, is a momentary overvoltage that suddenly appears in a circuit, exceeding the normal operating voltage. There are various reasons for surges in the charging and discharging circuit between the battery pack and the load and grid. For example, when the relay in the charging and discharging circuit between the battery pack and the load and grid is closed to discharge the battery pack to power the load or supply power to the grid, a transient change in current may occur, triggering a surge. Another example is when the battery pack is charging, the AC power supplied by the grid is converted to DC power by a PCS (Power Conversion System) and supplied to the battery pack. When the grid is struck by lightning, a lightning overvoltage is generated on the grid line, triggering a surge. Yet another example is when the battery pack is charging, and the load is supplying power to the battery pack. If the load malfunctions, an operational overvoltage may occur momentarily when the charging and discharging circuit is disconnected, triggering a surge. The surge voltage enters the battery pack along the charging and discharging circuit. Once the surge voltage exceeds the withstand voltage limit of the sampling chip, it can cause irreversible damage to the sampling chip.

[0049] Currently, the commonly used surge protection method is to discharge surge voltage using transient voltage suppressor (TVS) diodes. Considering factors such as cost, the design often only connects the TVS diode to the line between the positive terminal of the highest-value cell in the battery pack and the sampling chip, such as... Figure 1As shown. This is because when a surge voltage impacts the battery pack, due to the voltage difference between the individual battery cells connected in series, the positive terminal of the highest-voltage cell experiences the largest surge. Consequently, the pin on the sampling chip connected to the positive terminal of the highest-voltage cell suffers the largest surge voltage and has the highest risk of damage. Therefore, in this design, surge protection is implemented on the pins of the sampling chip most susceptible to surge voltage impact. This improves the safety of the sampling chip and reduces the number of surge protection devices introduced. For example, if the maximum surge voltage at the positive terminal of the highest-voltage cell is 110V and the voltage of each individual battery cell is 5V, then the maximum surge voltage at C1 is 105V, and the maximum surge voltage at D1 is 100V.

[0050] However, in actual operation, once a surge voltage enters the battery pack, although the surge voltage at the positive terminal of the highest-voltage cell can be reduced by the transient suppression diode, the positive terminals of the remaining cells are also subjected to surge voltage impacts because the circuits between each cell and the sampling chip are independent. The surge voltage flows along the sampling circuit to the internal parasitic circuit of the sampling chip for discharge, and then directly impacts the sampling chip, causing damage to the sampling chip. Specifically, in Figure 1 The sampling chip contains 16 switching transistors Q1 to Q16, each corresponding to one of the 16 battery cells. Each switching transistor is connected to the positive and negative terminals of a corresponding battery cell to form a sampling circuit. The surge voltage at C1 is transmitted to Q16 through C1, directly impacting the sampling chip. Figure 1 The internal parasitic circuit can be understood as a switching transistor.

[0051] Based on the above considerations, a battery pack was designed, including two first protection diodes. Surge voltages occurring at the positive terminal of the target battery cell closest to the overall positive terminal of the sampling chip are discharged by these first protection diodes. Furthermore, the sampling leads connected to the positive terminals of all battery cells other than the target battery cell are connected to a discharge circuit. The first terminal of this discharge circuit is also connected to any one of the first protection diodes. The core component of the discharge circuit is the discharge diode; surge voltages occurring at the positive terminals of all battery cells except the target battery cell are guided to the first protection diodes for discharge via the discharge circuit. In this battery pack, each pin of the sampling chip is surge protected, reducing the risk of overvoltage damage to the sampling chip's pins.

[0052] To enable those skilled in the art to better understand the technical solutions of this application, the battery pack provided in the embodiments of this application will be specifically described below with reference to the accompanying drawings and specific embodiments. First, the terms involved in this application will be explained:

[0053] As used in this article, the terms “sampling chip” and “analog front end (AFE) chip” are used interchangeably.

[0054] As used in this article, the term "channel" refers to the physical path within a chip used for data transmission, typically consisting of wires, transistors, etc. Each channel corresponds to a pin on the chip.

[0055] As used in this article, the terms “pin,” “pipe,” and “port” are interchangeable. A “pin” is a connection that leads from the internal circuitry of a chip to the external circuitry, forming the chip’s interface.

[0056] As used in this article, the term "voltage limit" refers to the maximum voltage that the sampling chip can withstand under normal operating conditions.

[0057] As used in this article, the term "highest-potential cell" refers to the cell with the highest potential in the battery pack. The positive electrode potential of the highest-potential cell is the total voltage of all the cells that make up the battery pack.

[0058] As used in this article, the term "clamping voltage" refers to the maximum voltage value that a transient suppression diode, Zener diode, or similar device will limit to a specific level when subjected to transient overvoltage or surge voltage.

[0059] The battery packs described in this application can be used, but are not limited to, in electrical equipment such as vehicles, ships, or aircraft. A power system for such electrical equipment can be constructed using battery packs and battery devices as described in this application.

[0060] In this application, the electrical devices using battery packs as power sources can be, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc. For the sake of brevity, the following embodiments all use electric vehicles as examples.

[0061] Please refer to Figure 2 , Figure 2This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0062] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0063] Figure 3 An exploded structural diagram of a battery device 100 according to an embodiment of this application is shown. Figure 3 As shown, the battery device 100 mentioned in the embodiments of this application may include a battery module 10. The battery module 10 includes N battery cells 11, which are connected in series via a busbar, where N is a positive integer greater than or equal to 2. The battery cell with the highest positive electrode potential among the N battery cells 11 is the target battery cell, i.e., the target battery cell is the highest-potential battery cell. This application does not specifically limit the number of battery cells 11 constituting the battery module 10; for example, in… Figure 4 In the example shown, battery pack 10 includes 16 individual battery cells, cell 1 to cell 16.

[0064] In some embodiments, the battery pack 10 is typically formed by arranging a plurality of battery cells 11. As an example, the battery pack 10 may be formed by bundling a plurality of battery cells 11 together with cable ties.

[0065] In some embodiments, such as Figure 3 As shown, the battery device can be a battery pack, which also includes a housing 6, in which the battery pack 10 is housed. The housing 6 can be a simple three-dimensional structure such as a single cuboid, cylinder, or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders, or spheres. The material of the housing 6 can be an alloy material such as aluminum alloy or iron alloy, a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin.

[0066] As an example, the battery pack 10 can be housed in the housing 6 by being fixed in the housing 6.

[0067] As an example, the housing 6 may include a first housing 61 and a second housing 62. The first housing 61 and the second housing 62 are fastened together to form a closed space inside the housing 6 to house the battery pack 10. Here, "closed" refers to covering or closing, and can be either non-sealed or sealed to prevent liquids or other foreign objects from affecting the charging or discharging of the individual battery cells 11. The first housing 61 may be a top cover or a bottom plate.

[0068] As an example, the housing 6 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 6 forms an enclosed space to accommodate the battery pack 10.

[0069] In some embodiments, the housing 6 may be part of the vehicle's chassis structure. For example, a portion of the housing 6 may be at least a portion of the vehicle's floor, or a portion of the housing 6 may be at least a portion of the vehicle's crossbeams and longitudinal beams.

[0070] The battery cell 11 involved in the embodiments of this application can be a secondary battery. A secondary battery refers to a battery cell 11 that can be used again after being discharged by recharging to activate the active material.

[0071] The battery cell 11 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application embodiment is not limited to this. As an example, the battery cell 11 can be a cylindrical battery cell, a prismatic battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells, etc., and this application has no particular limitations.

[0072] The battery cell 11 provided in the embodiments of this application includes a casing, an electrode assembly, and an electrolyte. The electrode assembly is the component in the battery cell 11 where the electrochemical reaction occurs. The electrode assembly and the electrolyte are housed within the casing. As an example, the electrolyte may be liquid, gel-like, or solid.

[0073] As examples, the outer casing can be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film. In some embodiments, the outer casing can be a sealed structure or a non-sealed structure. As an example, when the outer casing is a non-sealed structure, it serves to protect the electrode assembly, and a sealing bag is included between the outer casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film. When the outer casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0074] Please refer to Figures 4 to 7 The battery pack 10 provided in this application embodiment also includes a sampling chip 21. The sampling chip 21 can form a battery management system 2 with a microcontroller 22 (Microprogrammed Control Unit, MCU) to facilitate the control of the battery pack 10. The sampling chip 21 converts the collected analog signals into digital signals and sends them back to the MCU 22.

[0075] The sampling chip 21 has a total positive terminal VBAT, a total negative terminal GND, and at least N+1 sampling terminals. The total positive terminal is electrically connected to the positive terminal of the target battery cell through a power supply lead 41, and the total negative terminal is electrically connected to the negative terminal of the N battery cells 11 with the lowest positive potential through a grounding lead 42, forming a power supply circuit 4.

[0076] The battery pack 10 also includes N sampling circuits 3 and clamping circuits 5. Each of the N sampling circuits 3 corresponds one-to-one with one of the N battery cells 11. Each sampling circuit 3 has N+1 acquisition leads 31, such that the positive and negative terminals of each battery cell 11 are coupled to the sampling chip 21 through one acquisition lead 31. The acquisition lead 31 connected to the positive terminal of the target battery cell is designated as the target lead.

[0077] The clamping circuit 5 includes a discharge circuit 51, two first protection diodes, and N-1 connection nodes. The anodes of both first protection diodes are grounded. The cathode of one of the first protection diodes is connected to the power supply lead 41 at a first connection point, and the cathode of the other is connected to the target lead at a second connection point. The acquisition lead 31 connected to the anode of each battery cell 11 (excluding the target battery cell) is connected to the discharge circuit 51 at a corresponding connection node. The first end of the discharge circuit 51 is connected to either the power supply lead 41 or the target lead. A discharge diode is provided between any connection node and the first end of the discharge circuit 51 connected thereto, with the cathode of the discharge diode close to the cathode of the first protection diode connected thereto.

[0078] The power supply circuit 4 provides power to the sampling chip 21, enabling it to operate. The sampling chip 21 can be any chip that collects information about the battery cell 11 (e.g., voltage, temperature). The number of channels in the sampling chip 21 can be 2, 8, 16, 32, etc., and can be selected according to the actual operating conditions.

[0079] In the various figures of this application, the first connection point is shown as point A, and the second connection point is shown as point B. When the power supply lead 41 is connected to the first end of at least one discharge circuit 51, the first connection point A is located between the positive terminal of the target battery cell and the first end of the discharge circuit 51; similarly, the second connection point B is also located between the positive terminal of the target battery cell and the first end of the discharge circuit 51. It can be understood that the connection point between the negative terminal of any battery cell 11 and the positive terminal of an adjacent battery cell 11 is a series connection point, then the battery chain formed by N battery cells 11 connected in series has N-1 series connection points. Figure 4 In the specific example shown, the battery pack 10 includes 16 individual battery cells, cell 1 to cell 16, where cell 16 is the target battery cell. There are 15 series connection points, namely C1, D1, etc. To collect information from each individual battery cell 11, a sampling chip 21 with at least 17 sampling terminals, CB0 to CB16, is selected.

[0080] Each sampling loop 3 is used to collect information from a corresponding battery cell 11. One end of each sampling lead 31 is connected to a sampling terminal. In any two adjacent battery cells 11, the positive terminal of the battery cell 11 closer to the overall positive terminal is connected to a sampling terminal through a sampling lead 31, the series connection point of the two battery cells 11 is connected to a sampling terminal through a sampling lead 31, and the negative terminal of the battery cell 11 farther from the overall positive terminal is connected to a sampling terminal through a sampling lead 31, so that the positive and negative terminals of each battery cell 11 are coupled to the sampling chip 21 through a sampling lead 31. It can be understood that the sampling lead 31 connected to the positive terminal of cell n-1 and the sampling lead 31 connected to the negative terminal of cell n are shared, where n is a positive integer and N≥n≥2.

[0081] The N-1 battery cells 11, excluding the target battery cell, correspond one-to-one with the N-1 connection nodes. The discharge circuit 51 is equipped with discharge diodes, and one or more discharge diodes may be provided between each connection node and the first terminal of the discharge circuit 51 connected thereto.

[0082] It should be noted that the term "ground" in this application should be interpreted broadly. It can be understood as power ground, i.e., the main negative terminal GND or the grounding lead 42 connected to the main negative terminal GND, or as protective ground, such as the casing 6 of the battery pack 10 and the earth. Based on this, the positive terminal of the first protection diode can be connected to any one of the main negative terminal GND, the grounding lead 42, and the protective ground.

[0083] It is worth noting that the electrical connection between the positive terminal of the target battery cell and the overall positive terminal can be implemented as a direct connection or an indirect connection, specifically through a filter circuit (e.g., RC circuit, LC circuit), a voltage regulator circuit, etc. The specific implementation methods of other circuit connections described in this article can refer to the implementation methods of the electrical connection between the positive terminal of the target battery cell and the overall positive terminal, and will not be repeated here.

[0084] In this embodiment, when the battery pack 10 is in operation and no surge voltage occurs, the voltage at the positive terminal of the target battery cell and the voltage at the N-1 series connection points are both within the normal operating voltage range, and both first protection diodes are in a non-conducting state. When a surge voltage occurs, if the surge voltage at the positive terminal of the target battery cell is greater than the reverse breakdown voltage of the first protection diode, both first protection diodes are in a conducting state. The surge voltage at the positive terminal of the target battery cell flows along the power supply lead 41 to the first connection point A and is discharged through the first protection diode. The surge voltage at the positive terminal of the target battery cell flows along the target lead to the second connection point B and is discharged through the first protection diode, thereby clamping the surge voltage at the positive terminal of the target battery cell to below the withstand voltage limit of the sampling chip 21. Simultaneously, when the surge voltage between two adjacent battery cells 11 is too high, the discharge diode between the connection node of the shared acquisition lead 31 and the discharge circuit 51 and the first terminal of the discharge circuit 51 is turned on. The series connection point of the two adjacent battery cells 11, the acquisition lead 31 connected to the series connection point, the connection node of the acquisition lead 31 and the discharge circuit 51, the first terminal of the discharge circuit 51 and the negative terminal of the first protection diode are connected in sequence to form a discharge path. The instantaneous overvoltage between the two adjacent battery cells 11 flows along the discharge path to the first protection diode, and is then discharged to ground through the first protection diode, so that the surge voltage between the two adjacent battery cells 11 is clamped to a value lower than the withstand voltage limit of the sampling chip 21.

[0085] The battery pack 10 in this embodiment is equipped with a clamping circuit 5, which includes two first protection diodes. The negative terminals of the two first protection diodes are connected to the power supply lead 41 and the target lead, respectively. In this way, when a surge voltage enters the battery pack 10, the surge voltage borne by the positive terminal of the target battery cell can be discharged through the first protection diodes, thereby protecting the overall positive terminal and a sampling terminal connected to the target lead from damage caused by the surge voltage.

[0086] Based on this, thanks to the clamping circuit 5 also having a discharge circuit 51, the acquisition leads 31 connected to the positive terminals of the N-1 battery cells 11 (excluding the target battery cell) are all connected to the discharge circuit 51, and the first end of the discharge circuit 51 is connected to the power supply lead 41 or the target lead. Thus, when a surge voltage enters the battery pack 10, the surge voltage at the series connection point is guided to the power supply lead 41 or the target lead through the discharge circuit 51, causing the surge voltage to be conducted to the first protection diode for discharge. This reduces the possibility that the surge voltage at the series connection point will be conducted through the sampling circuit 3 and discharged to the internal parasitic circuit of the sampling chip 21. Therefore, the damage to the sampling terminals connected to the acquisition leads 31 (excluding the target lead) from surge voltage impacts is also effectively reduced.

[0087] In summary, this embodiment is designed to provide surge protection for all pins of the sampling chip 21, reducing the risk of damage to the sampling chip 21 due to surge voltage impacts and improving the operational stability and safety of the battery pack 10.

[0088] It should also be noted that those skilled in the art would readily consider configuring a first protection diode for each acquisition lead 31, which could lead to an excessive number of first protection diodes and high costs. Alternatively, those skilled in the art would also readily consider using a chip with a high withstand voltage limit as the sampling chip 21, but for any particular chip model, its manufacturing technology is mature. Therefore, in order to increase the withstand voltage limit of a chip to no less than the surge voltage, high design and manufacturing costs are required.

[0089] This embodiment combines two first protection diodes and a discharge circuit 51. The surge voltage between two adjacent battery cells is guided to either of the two first protection diodes for discharge through the discharge circuit 51. Compared with the method of configuring a first protection diode for each acquisition lead 31, it has the effect of using fewer first protection diodes. Compared with the method of using a chip with a high withstand voltage limit as the sampling chip 21, it has the following effects: First, existing model chips can be directly used as the sampling chip 21, which can save the design and manufacturing costs caused by chip improvement. Second, by introducing a discharge circuit 51 containing discharge diodes, instantaneous overvoltage can be effectively discharged through the discharge circuit 51 and the first protection diodes, thus optimizing the surge protection effect of the sampling chip 21.

[0090] According to some embodiments of this application, the first protection diode can be... Figures 4 to 7 The transient voltage suppressor diode shown, or the first protection diode, can also be a Zener diode. Transient voltage suppressor diodes have the advantages of fast response speed and strong surge carrying capacity.

[0091] According to some embodiments of this application, the discharge diode can be any one of a Schottky barrier diode (SBD), a silicon diode, and a germanium diode. Figure 4 and Figure 5 In this circuit, the number of bleeder diodes is equal to the number of battery cells 11. The bleeder diodes are implemented as Schottky diodes, that is, there are 16 Schottky diodes D1 to D16. Compared with silicon and germanium diodes, Schottky diodes have a lower forward voltage drop, so they can conduct quickly, which helps to reduce the possibility of surge voltage being transmitted along the sampling circuit 3 and impacting the sampling chip 21.

[0092] According to some embodiments of this application, such as Figures 4 to 7 As shown, the discharge circuit 51 may include at least two discharge diodes connected in parallel. The positive terminal of one of the two discharge diodes is grounded, and the negative terminal is connected to the positive terminal of the other of the two discharge diodes at a connection node. The negative terminal of the other of the two discharge diodes is close to the negative terminal of the first protection diode connected to it.

[0093] In other words, one of the two discharge diodes connected in parallel is located between a connection node and the first end of the discharge circuit 51 connected thereto.

[0094] In this embodiment, the two parallel discharge diodes constitute part of the discharge circuit 51. These two discharge diodes can provide discharge paths in different directions for the surge voltage between two adjacent battery cells 11. When a negative surge voltage impacts the battery pack 10, the negative surge voltage can be discharged through the discharge diode with its positive terminal grounded.

[0095] According to some embodiments of this application, there may be N-1 discharge circuits 51, and each of the N-1 discharge circuits 51 corresponds to one of the N-1 battery cells 11 excluding the target battery cell.

[0096] In this example, the acquisition leads 31 connected to the positive terminals of the N-1 battery cells 11 (excluding the target battery cell) are all connected to a corresponding discharge circuit 51 at a connection node. That is, the N-1 connection nodes correspond one-to-one with the N-1 discharge circuits 51.

[0097] As an example of this application, such as Figure 5 As shown, the negative terminals of the 15 battery cells (cells 1 to 15, excluding the target battery cell) connected to the acquisition leads 31 are each connected to a discharge circuit 51 at a connection node. The first end of each discharge circuit 51 is connected to the target lead. Each discharge circuit 51 has two discharge diodes connected in parallel, with the positive terminal of one diode grounded and its negative terminal connected to the positive terminal of the other diode at the connection node. In this design, when the series connection point is subjected to a positive surge voltage, the positive surge voltage at the series connection point flows along the acquisition lead 31 to the corresponding connection node, and then is guided through the discharge diode located between the connection node and the first end of the discharge circuit 51 to the first protection diode for discharge. Specifically, in Figure 5 In the series connection point C1, the discharge path of the forward surge voltage is: C1-C1 connected to the acquisition lead-D16.1-DZ2-ground. It can be understood that the voltage at C1 can be clamped by the sum of the forward conduction voltage drop of the discharge diode D16.1 and the clamping voltage of the first protection diode DZ2.

[0098] When the series connection point is subjected to a negative surge voltage, the negative surge voltage at the series connection point flows along the acquisition lead 31 where the series connection point is located to the corresponding connection node, and then is discharged to ground through the discharge diode located between the connection node and ground on the discharge circuit 51. Specifically, in Figure 5 In the series connection point C1, the discharge path of the negative surge voltage is: C1-C1 connected to the acquisition lead-D16.2-ground.

[0099] As another example of this application, overall it is consistent with Figure 5 The example shown is the same, except that in this embodiment, the first end of each discharge circuit 51 is connected to the power supply lead 41.

[0100] As another example of this application, such as Figure 6 As shown, overall with Figure 5The example shown is the same, except that in this embodiment, the first end of part of the discharge circuit 51 is connected to the power supply lead 41, and the first end of the remaining part of the discharge circuit 51 is connected to the target lead.

[0101] By designing N-1 discharge circuits 51, each of the N-1 battery cells 11 other than the target battery cell corresponds to one discharge circuit 51, so that when the positive terminal is subjected to a surge voltage impact, the surge voltage is guided to the first protection diode through the corresponding discharge circuit 51 to achieve discharge.

[0102] According to some embodiments of this application, such as Figure 4 , Figure 5 and Figure 7 As shown, a discharge circuit 51 can also be provided. In this example, the discharge circuit 51 may include N discharge diodes corresponding one-to-one with the N battery cells 11. The positive and negative terminals of each discharge diode are respectively connected across the two acquisition leads 31 of the corresponding battery cell 11, and the N discharge diodes are connected in sequence.

[0103] In this embodiment, N-1 connection nodes are located on the same discharge circuit 51, and the acquisition leads 31 connected to the N-1 battery cells 11 (excluding the target battery cell) are all connected to the discharge circuit 51. Since the N discharge diodes are connected in sequence, two adjacent discharge diodes are connected to one connection node.

[0104] As an example of this application, such as Figure 4 and Figure 5 As shown, the discharge circuit 51 includes 16 discharge diodes D1 to D16. The positive and negative terminals of discharge diode D1 are connected across the acquisition lead 31 connected to the negative terminal of battery cell 1 and the acquisition lead 31 connected to the positive terminal of battery cell 1, respectively. The positive and negative terminals of discharge diode D2 are connected across the acquisition lead 31 connected to the negative terminal of battery cell 2 and the acquisition lead 31 connected to the positive terminal of battery cell 2, respectively, and so on. Correspondingly, the first terminal of the discharge circuit 51 is connected to the target lead. It is understood that since the acquisition lead 31 connected to the negative terminal of cell 1 is also connected to the overall negative terminal, the positive terminal of discharge diode D1 can be grounded.

[0105] In this example, for any series connection point, when subjected to a forward surge voltage, all the discharge diodes located between the connection node connected to the series connection point and the first terminal of the discharge circuit 51 are turned on to guide the forward surge voltage to the first protection diode. Specifically, in Figure 5In the circuit diagram, the discharge path of the forward surge voltage at the series connection point C1 is: C1 - the acquisition lead connected to C1 - the connection node between the acquisition lead connected to C1 and the discharge circuit 51 - D16 - DZ2 - ground. The discharge path of the forward surge voltage at the series connection point D1 is: D1 - the acquisition lead connected to D1 - the connection node between the acquisition lead connected to D1 and the discharge circuit 51 - D15 - D16 - DZ2 - ground, and so on. It can be understood that the voltage at C1 can be clamped by the sum of the forward voltage drop of the discharge diode D16 and the clamping voltage of the first protection diode DZ2. Similarly, the voltage at D1 can be clamped by the sum of the forward voltage drop of the discharge diode D15, the forward voltage drop of the discharge diode D16, and the clamping voltage of the first protection diode DZ2. Therefore, it can be seen that the forward voltage drop of the bleeder diode affects the voltage value after the surge voltage is clamped. When a Schottky diode is selected as the bleeder diode, the surge voltage can be clamped to a safer voltage value because the forward voltage drop of the Schottky diode is lower.

[0106] Conversely, for any series connection point, when subjected to a negative surge voltage, all the discharge diodes located between the connection node connected to the series connection point and the second terminal of the discharge circuit 51 conduct to guide the negative surge voltage to ground. Specifically, in Figure 5 In the series connection point C1, the discharge path of the negative surge voltage is: C1-C1 connected to the acquisition lead-C1 connected to the connection node of the acquisition lead connected to C1 and the discharge circuit 51-D15-D14-D13-D12-D11-D10-D9-D8-D7-D6-D5-D4-D3-D2-D1-ground. The discharge path of the negative surge voltage at the series connection point D1 is: D1-D1 connected to the acquisition lead-D1 connected to the connection node of the acquisition lead connected to D1 and the discharge circuit 51-D14-D13-D12-D11-D10-D9-D8-D7-D6-D5-D4-D3-D2-D1-ground, and so on.

[0107] As another example of this application, the negative terminal of the bleeder diode D16 can be replaced by being connected across the power supply lead 41. In this example, the positive surge voltage at each series connection point is guided to the first protection diode DZ1 through the bleeder circuit 51 and then discharged to ground.

[0108] Compared to having N-1 discharge circuits, this embodiment only has one discharge circuit 51, which simplifies the circuit design of the battery pack 10, reduces circuit complexity, and reduces the difficulty of circuit wiring and installation.

[0109] Of course, in other embodiments of this application, some of the battery cells 11 may be connected to a single discharge circuit 51, and the remaining battery cells 11 may be connected to the same discharge circuit 51.

[0110] Based on some embodiments of this application, please continue to refer to Figure 6 and Figure 7 The clamping circuit 5 may also include a second protection diode, the positive terminal of which is grounded. Either the power supply lead 41 or the target lead is connected to the first terminal of the discharge circuit 51 and also to the negative terminal of the second protection diode.

[0111] Similar to the first protection diode, the second protection diode can be either a transient voltage suppressor diode or a Zener diode; this application does not impose any specific restrictions on this.

[0112] This embodiment is designed in such a way that when the power supply lead 41 is connected to the first end of the discharge circuit 51, a second protection diode is connected to the power supply lead 41; the target lead is connected to the first end of the discharge circuit 51 and a second protection diode is also connected at the same time.

[0113] Specifically, in Figure 6 In the example shown, when a forward surge voltage occurs at the positive terminal of the target battery cell, the surge voltage is conducted along the power supply lead 41 to the first connection point A and discharged through the first protection diode, thus suppressing the forward surge voltage to a first voltage value. When the first voltage value is still higher than the withstand voltage limit of the sampling chip 21, it indicates that the forward surge voltage is too large to be completely clamped. The surge voltage continues to travel along the power supply lead 41 and reaches the second protection diode for discharge, further clamping the surge voltage to a second voltage value. The second voltage value is lower than the withstand voltage limit of the sampling chip 21, so the voltage at the overall positive terminal is lower than the withstand voltage limit of the sampling chip 21, preventing overvoltage damage to the overall positive terminal. The principle of suppressing the forward surge voltage at the positive terminal of the target battery cell after it is transmitted along the target lead is similar to the principle of suppressing it after it is transmitted along the power supply lead 41, and will not be repeated here in this embodiment.

[0114] In this embodiment, a second protection diode is also connected to the power supply lead 41 and / or the target lead to share the surge voltage discharge. When a positive surge voltage occurs at the positive terminal of the target battery cell, the power supply lead 41 and the target lead connected to the second protection diode achieve multi-stage clamping through the synergistic action of multiple protection components. This allows the surge voltage to be suppressed to below the withstand voltage limit of the sampling chip 21 after multiple clampings, i.e., the surge voltage is clamped to a safe value. This reduces the risk of damage to the sampling chip 21 caused by the surge voltage impact, thus reducing the discharge burden on the first protection diode.

[0115] According to some embodiments of this application, the first protection diode can be arranged closer to the positive terminal of the target battery cell than the first end of the discharge circuit 51 connected thereto, and the second protection diode can be arranged closer to the sampling chip 21 than the first end of the discharge circuit 51 connected thereto.

[0116] As an example, when the power supply lead 41 is connected to the first terminal of the discharge circuit 51, the power supply lead 41 is also connected to the negative terminal of the second protection diode, and the connection point between the first terminal of the discharge circuit 51 and the power supply lead 41 is located between the first connection point A and the connection point between the negative terminal of the second protection diode and the power supply lead 41. As an example, when the target lead is connected to the first terminal of the discharge circuit 51, the target lead is also connected to the negative terminal of the second protection diode, and the connection point between the first terminal of the discharge circuit 51 and the target acquisition lead is located between the second connection point B and the connection point between the negative terminal of the second protection diode and the target lead.

[0117] In this embodiment, the first terminal of the discharge circuit 51 is located between the negative terminals of the first protection diode and the second protection diode. The surge voltage borne by the positive terminals of the N-1 battery cells other than the target battery cell is transmitted to the track through the discharge circuit. It can be transmitted to the first protection diode for discharge or to the second protection diode for discharge, thus enabling rapid discharge. This can further reduce the discharge burden on the first protection diode.

[0118] According to some embodiments of this application, such as Figures 4 to 7 As shown, a resistor can be connected in series on the power supply lead 41 and each acquisition lead 31.

[0119] The location and number of resistors are not limited. A resistor can be placed between the positive terminal of the target battery cell and the first connection point A on the power supply lead 41. This resistor can share some of the surge voltage transmitted from the positive terminal of the target battery cell, thus beneficially reducing the discharge burden on the first protection diode. For example... Figure 6As shown, when the power supply lead 41 is also connected to the first terminal of the discharge circuit 51, a resistor can also be provided between the first connection point A and the first terminal of the discharge circuit 51 on the power supply lead 41. This resistor can share part of the surge voltage transmitted from the series connection point, thus having a beneficial effect on reducing the discharge burden of the first protection diode. When the power supply lead 41 is also connected to the negative terminal of the second protection diode, a resistor can also be provided between the first terminal of the discharge circuit 51 and the negative terminal of the second protection diode on the power supply lead 41. This resistor can slow down the speed at which the surge voltage transmitted from the series connection point directly acts on the second protection diode, so that the second protection diode only conducts when the surge overvoltage is too high. This design can optimize the cooperative operation of the first and second protection diodes, making the triggering of the first and second protection diodes more orderly.

[0120] The position of the resistor on the target lead can be referenced from the position of the resistor on the power supply lead 41, which will not be repeated here in this embodiment.

[0121] By introducing a resistor, the resistor can share part of the surge voltage, which has a positive effect on the surge protection of the sampling chip 21. This further reduces the risk of the sampling chip 21 being damaged by surge voltage and improves the overall stability and reliability of the circuit between the battery pack 10 and the sampling chip 21.

[0122] On the acquisition leads 31 connected to the positive terminals of the N-1 battery cells 11 (excluding the target battery cell), a resistor may be provided between the connection node and the sampling terminal connected thereto. For example... Figure 4 and Figure 5 As shown, resistors are provided on the acquisition leads 31 connected to the positive terminals of the 15 battery cells other than the target battery cell, that is, there are 15 resistors R1 to R15.

[0123] According to some embodiments of this application, the resistor on the acquisition lead 31 can be connected between the battery cell 11 and the corresponding connection node.

[0124] Based on the preceding description, it can be seen that the resistance on the acquisition lead 31 connected to the positive terminal of each battery cell 11 (excluding the target battery cell) is located on its corresponding discharge path and before the discharge diode. Specifically, in Figure 7 In the example, the discharge path of the forward surge voltage at the series connection point C1 is: C1-C1 connected to the acquisition lead-R15-D16-DZ2-R16-ground. In this example, R15 can share part of the surge voltage transmitted from C1, which can have a beneficial effect on reducing the discharge burden of the discharge diode D16.

[0125] In this embodiment, a resistor is provided between the positive terminal of the battery cell 11 and the corresponding connection node on the acquisition lead 31 where the series connection point is located. This resistor limits the surge voltage at the series connection point before it is guided to the discharge circuit 51, thereby reducing the discharge burden on the discharge diode.

[0126] According to some embodiments of this application, this application also provides an energy storage device, which includes a battery pack 10 as provided in any of the above embodiments, the battery pack 10 being used to provide electrical energy, or including a battery device as provided in any of the above embodiments.

[0127] As an example, energy storage devices can be energy storage containers or energy storage cabinets. Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it when appropriate. For example, energy storage devices can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours.

[0128] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application.

[0129] Example 1

[0130] like Figure 4 As shown, this embodiment provides a battery pack 10 including 16 battery cells 1 to 16 connected in series, a sampling chip 21, and a clamping circuit 5. Among the 16 battery cells 11, the battery cell 16 with the highest positive electrode potential is the target battery cell. The sampling chip 21 is connected to an MCU 22 and has a total positive terminal VBAT, a total negative terminal GND, and at least 17 sampling terminals CB0 to CB16.

[0131] The positive terminal is electrically connected to the positive electrode of the target battery cell through the power supply lead 41, and the negative terminal is electrically connected to the negative electrode of the battery cell 1 with the lowest positive electrode potential among the 16 battery cells 11 through the grounding lead 42, forming a power supply circuit 4.

[0132] Seventeen sampling terminals CB0 to CB16 are each connected to the battery chain via a sampling lead 31, forming 16 sampling loops 3. Each sampling loop 3 corresponds one-to-one with a single battery cell 11, resulting in 17 sampling leads 31. The sampling lead 31 connected to the positive terminal of the target battery cell is called the target lead.

[0133] The clamping circuit 5 includes a discharge circuit 51 and two TVS diodes. The positive terminals of both TVS diodes are grounded. The negative terminal of one TVS diode DZ1 is connected to the power supply lead 41 at the first connection point A, and the negative terminal of the other TVS diode DZ2 is connected to the target lead at the second connection point B. The discharge circuit 51 is equipped with 16 Schottky diodes D1 to D16 corresponding to 16 battery cells 11. The positive and negative terminals of each Schottky diode are connected across the acquisition lead 31 connected to the negative terminal and the acquisition lead 31 connected to the positive terminal of the corresponding battery cell 11, respectively. Two adjacent Schottky diodes are connected to a connection node, so that the first end of the discharge circuit 51 is connected to the target lead at point C, and the second end is connected to the acquisition lead 31 connected to the negative terminal of the battery cell closest to the total negative terminal at point D. Thus, the discharge circuit 51 and the acquisition leads 31 at the 15 series connection points are each connected to a connection node, and point B is located between point C and the positive terminal of the target battery cell 16.

[0134] The clamping voltage of the TVS diode is set to 85V, the withstand voltage limit of the sampling chip 21 is 100V, and the forward voltage drop of the Schottky diode is 0.4V. When a surge voltage enters the battery pack 10, if the maximum surge voltage at the positive terminal B1 of the target battery cell is 110V, then the maximum surge voltage at the series connection point C1 is 105V, and the maximum surge voltage at the series connection point D1 is 100V.

[0135] The clamping principle of clamping circuit 5 is as follows: the surge voltage at the positive terminal B1 of the target battery cell is transmitted along the target lead to the TVS diode DZ2 for discharge. TVS diode DZ2 can clamp the voltage at the positive terminal B1 of the target battery cell to 85V. Correspondingly, the voltage at the sampling terminal CB16 is clamped to 85V, which is not higher than the withstand voltage limit of the sampling chip 21, thus protecting the sampling terminal CB16. The discharge path of the surge voltage at the series connection point C1 is: C1 - the acquisition lead where C1 is located - D16 - the highest segment acquisition lead - TVS diode DZ2. Therefore, the voltage at the series connection point C1 can be clamped to 85.4V. Correspondingly, the voltage at the sampling terminal CB15 is clamped to 85.4V, which is not higher than the withstand voltage limit of the sampling chip 21, thus protecting the sampling terminal CB15. For similar reasons, the surge voltage discharge path at the series connection point D1 is: D1-D1 acquisition lead-D15-D16-highest acquisition lead-TVS tube DZ2, and the voltage at the series connection point D1 and sampling terminal CB14 is clamped at 85.8V.

[0136] Example 2

[0137] This embodiment is largely the same as Embodiment 1, except that: Figure 7As shown, in this embodiment, the clamping circuit 5 also includes a TVS diode DZ3 and 17 resistors R0 to R17. The positive terminal of the TVS diode DZ3 is grounded, and the negative terminal is connected to the target lead at point E. Point C is located between points B and E. The 17 resistors R0 to R16 are correspondingly arranged on the 17 acquisition leads 31. Resistor R16 is located between points B and C, and resistors R0 to R15 are located between the series connection point and the connection node. Resistor R17 is connected in series on the power supply lead 41.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery pack, characterized in that, include: N battery cells connected in series, wherein the battery cell with the highest positive electrode potential is the target battery cell; where N is a positive integer greater than or equal to 2; The sampling chip has a total positive terminal; the positive terminal of the target battery cell is electrically connected to the total positive terminal via a power supply lead; N sampling circuits, each corresponding to one of the N battery cells, have N+1 acquisition leads, such that the positive and negative terminals of each battery cell are coupled to the sampling chip through one of the acquisition leads; the one of the acquisition leads connected to the positive terminal of the target battery cell is the target lead; The clamping circuit includes a discharge circuit, two first protection diodes, and N-1 connection nodes. The anodes of the two first protection diodes are grounded, and the cathodes of the two first protection diodes are connected to the power supply lead and the target lead, respectively. The acquisition lead connected to the anode of each battery cell (excluding the target battery cell) is connected to the discharge circuit at a corresponding connection node. The first end of the discharge circuit is connected to either the power supply lead or the target lead. A discharge diode is provided between any connection node and the first end of the discharge circuit connected thereto, with the cathode of the discharge diode close to the cathode of the first protection diode connected thereto.

2. The battery pack according to claim 1, characterized in that, The discharge circuit includes at least two discharge diodes connected in parallel. The positive terminal of one of the two discharge diodes is grounded, and the negative terminal is connected to the positive terminal of the other of the two discharge diodes at a connection node. The negative terminal of the other of the two discharge diodes is close to the negative terminal of the first protection diode connected to it.

3. The battery pack according to claim 2, characterized in that, The discharge circuit is provided with N-1 circuits, and each of the N-1 discharge circuits corresponds to one of the N-1 battery cells other than the target battery cell.

4. The battery pack according to claim 2, characterized in that, The discharge circuit includes N discharge diodes corresponding one-to-one with the N battery cells. The positive and negative terminals of each discharge diode are respectively connected across the two acquisition leads of the sampling circuit where the corresponding battery cell is located, and the N discharge diodes are connected in sequence.

5. The battery pack according to claim 1, characterized in that, The clamping circuit also includes a second protection diode, the positive terminal of which is grounded; Either the power supply lead or the target lead is connected to the first terminal of the discharge circuit and also to the negative terminal of the second protection diode.

6. The battery pack according to claim 5, characterized in that, The first protection diode is closer to the positive terminal of the target battery cell than the first terminal of the discharge circuit connected to it, and the second protection diode is closer to the sampling chip than the first terminal of the discharge circuit connected to it.

7. The battery pack according to claim 1, characterized in that, A resistor is connected in series with each of the power supply leads and each of the acquisition leads.

8. The battery pack according to claim 7, characterized in that, The resistor on the acquisition lead is connected between the battery cell and the corresponding connection node.

9. The battery pack according to any one of claims 1 to 6, characterized in that, The first protection diode is a transient voltage suppressor diode or a Zener diode; And / or, the discharge diode is any one of a Schottky diode, a silicon diode, and a germanium diode.

10. A battery device, characterized in that, Includes the battery pack as described in any one of claims 1 to 9.

11. An electrical appliance, characterized in that, The electrical equipment includes a battery pack as described in any one of claims 1 to 9, the battery pack being used to provide electrical energy, or includes a battery device as described in claim 10, the battery device being used to provide electrical energy.

12. An energy storage device, characterized in that, The energy storage device includes a battery pack as described in any one of claims 1 to 9 or a battery device as described in claim 10.

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