Battery Management System

Abstract

This application provides a battery management system. The battery management system manages a battery pack and includes a data acquisition unit and a main control board. At least two data acquisition units are provided, and any two adjacent data acquisition units are wirelessly connected. Each data acquisition unit is configured to be electrically connected to at least two batteries in the battery pack in a one-to-one correspondence, and is used to acquire battery performance information of each battery. The main control board is wirelessly connected to each data acquisition unit, and is used to receive the battery performance information sent by the data acquisition unit, generate control information based on the battery performance information, and use the control information to control the battery pack. This application can improve the stability of the battery management system and reduce maintenance costs.

Description

Technical Field

[0001] This application relates to the field of battery management technology, and more specifically, to a battery management system. Background Technology

[0002] With the continuous development of IoT technology, more and more smart devices are being applied in various fields, such as transportation, healthcare, and supermarkets. These smart devices require battery management systems to manage the battery and maintain normal operation. In related technologies, the various components within a battery management system are typically connected via complex wiring harnesses and connectors to achieve signal acquisition and transmission.

[0003] However, existing wired connection methods suffer from problems such as numerous connection points, complex structures, aging wire harnesses, and loose or detached connectors, resulting in poor system stability and high maintenance costs. Utility Model Content

[0004] This application addresses the shortcomings of existing methods by proposing a battery management system to solve the technical problems of poor stability or high maintenance costs in related technologies.

[0005] This application provides a battery management system for managing a battery pack, including: The acquisition unit is provided with at least two, and any two adjacent acquisition units are wirelessly connected. Each acquisition unit is configured to be electrically connected to at least two batteries in the battery pack in a one-to-one correspondence, and is used to acquire battery performance information of each battery. The main control board is wirelessly connected to each of the acquisition units and is used to receive the battery performance information sent by the acquisition units, generate control information based on the battery performance information, and control the battery pack.

[0006] In one possible implementation, the acquisition unit includes a near-field communication module, which includes an electrically connected near-field communication chip and an antenna resonant circuit. The near-field communication chip is configured to interact with adjacent acquisition units or the main control board in a non-contact manner through the antenna resonant circuit.

[0007] In one possible implementation, the antenna resonant circuit includes a first inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, and a first resistor; The first terminal of the first inductor, the first terminal of the first capacitor, and the first terminal of the third capacitor are electrically connected to the first node. The second terminal of the first inductor, the first terminal of the second capacitor, and the first terminal of the fourth capacitor are electrically connected to the second node. The first end of the first resistor is electrically connected to the second end of the first capacitor, and the second end of the first resistor is electrically connected to the second end of the second capacitor. The first differential antenna port of the near-field communication chip is electrically connected to the second terminal of the third capacitor, and the second differential antenna port of the near-field communication chip is electrically connected to the second terminal of the fourth capacitor.

[0008] In one possible implementation, the acquisition unit further includes a voltage acquisition circuit; The voltage acquisition circuit includes a first fuse element, a second fuse element, a fifth capacitor, a sixth capacitor, and a seventh capacitor; The first end of the first fuse element and the first end of the second fuse element are both configured to be electrically connected to the positive terminal of the battery. The first power input terminal of the near-field communication chip, the second terminal of the first fuse element, the first terminal of the sixth capacitor, and the first terminal of the seventh capacitor are all configured to be electrically connected to the positive terminal of the power supply; the second terminal of the sixth capacitor and the second terminal of the seventh capacitor are both grounded. The second power input terminal of the near-field communication chip and the second terminal of the second fuse element are both electrically connected to the first terminal of the fifth capacitor, and the second terminal of the fifth capacitor is grounded; the first terminal of the first voltage divider resistor is electrically connected to the second terminal of the second fuse element.

[0009] In one possible implementation, the acquisition unit further includes a current acquisition circuit; The current acquisition circuit includes a shunt and an eighth capacitor; The current detection input terminal of the near-field communication chip, the first end of the shunt and the first end of the eighth capacitor are electrically connected to the positive current detection node. The current detection output terminal of the near-field communication chip, the second terminal of the shunt, and the second terminal of the eighth capacitor are electrically connected to the negative terminal node of the current detection. The positive current detection node and the negative current detection node are electrically connected to both ends of the power path of the battery, respectively.

[0010] In one possible implementation, the acquisition unit further includes at least one temperature acquisition circuit; The temperature acquisition circuit includes a temperature sensor and a bypass capacitor; The first terminal of the temperature sensor and the first terminal of the bypass capacitor are both electrically connected to the temperature input terminal of the near-field communication chip; the second terminal of the temperature sensor and the second terminal of the bypass capacitor are both grounded. The first end of the temperature sensor is configured to contact the temperature detection point of the battery.

[0011] In one possible implementation, the acquisition unit further includes a passive equalization circuit: The passive equalization circuit includes a field-effect transistor and a second resistor; The gate of the field-effect transistor and the first terminal of the second resistor are both electrically connected to the equalization control terminal of the near-field communication chip. The source of the field-effect transistor and the second terminal of the second resistor are both configured to be electrically connected to the negative terminal of the battery. The drain of the field-effect transistor is configured to be electrically connected to the positive terminal of the battery.

[0012] In one possible implementation, the main control board includes: A radio manager communicates wirelessly with the acquisition unit to receive the battery performance information sent by the acquisition unit; The processor is electrically connected to the radio manager via a serial bus and is used to receive the battery performance information transmitted by the radio manager, and to monitor and control the charging and discharging status of the battery pack based on the battery performance information.

[0013] In one possible implementation, the radio manager includes a radio frequency communication module; The radio frequency communication module includes a radio frequency chip, a matching circuit, a first antenna, and a second antenna; The matching circuit includes a second inductor, a fourth inductor, a nineteenth capacitor, a twentieth capacitor, a twenty-second capacitor, and a twenty-third capacitor. The first terminal of the second inductor and the first terminal of the fourth inductor are electrically connected; The second terminal of the second inductor, the first terminal of the nineteenth capacitor, and the first terminal of the twentieth capacitor are electrically connected to the third node; the second terminal of the twentieth capacitor is electrically connected to the first differential antenna port of the RF chip; the second terminal of the nineteenth capacitor is coupled to the first antenna. The second terminal of the fourth inductor, the first terminal of the twenty-second capacitor, and the first terminal of the twenty-third capacitor are electrically connected to the fourth node; the second terminal of the twenty-third capacitor is electrically connected to the second differential antenna port of the RF chip; and the second terminal of the twenty-second capacitor is coupled to the second antenna.

[0014] In one possible implementation, the radio frequency communication module further includes a first coupling circuit; The first coupling circuit includes a thirty-first capacitor, a seventh resistor, a seventh inductor, a forty-third capacitor, and a forty-fourth capacitor; the first terminal of the thirty-first capacitor is electrically connected to the second terminal of the nineteenth capacitor; the second terminal of the thirty-first capacitor is electrically connected to the first terminal of the seventh resistor; the second terminal of the seventh resistor, the first terminal of the seventh inductor, and the first terminal of the forty-fourth capacitor are electrically connected to the fifth node; the second terminal of the seventh inductor, the first terminal of the forty-third capacitor, and the first terminal of the first antenna are electrically connected to the sixth node; the second terminals of the forty-fourth capacitor, the forty-third capacitor, and the first antenna are all grounded.

[0015] The beneficial technical effects of the technical solutions provided in this application include: In this embodiment, battery performance information of each battery is collected by a data acquisition unit. The main control board receives the battery performance information sent by the data acquisition unit and generates control information based on the battery performance information. This enables precise monitoring and control of the charging and discharging state of each battery in the battery pack, thereby improving the safety of battery use. Furthermore, through wireless communication between any two adjacent data acquisition units, and wireless communication between the main control board and each data acquisition unit, the number of connection harnesses and connectors in the battery management system can be reduced. This not only simplifies the circuit structure of the battery management system, making it more stable and easier to maintain, but also avoids electrical isolation problems that may be caused by traditional wired connections, thus improving the overall stability and reliability of the system.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0017] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 A schematic diagram of the framework structure of a battery management system provided in an embodiment of this application; Figure 2 A schematic diagram of the circuit structure of a data acquisition unit in a battery management system provided in an embodiment of this application; Figure 3 A schematic diagram of the frame structure of the main control board in a battery management system provided in an embodiment of this application; Figure 4 This is a schematic diagram of the circuit structure of the radio manager of the main control board in a battery management system provided in an embodiment of this application. Explanation of reference numerals in the attached figures: 11-Acquisition unit; 111-Antenna resonant circuit; 112-Voltage acquisition circuit; 113-Current acquisition circuit; 114-First temperature acquisition circuit; 115-Second temperature acquisition circuit; 116-Passive equalization circuit; 117-First crystal oscillator circuit; 12-Main control board; 121-Radio manager; 121a-Matching circuit; 121b-First coupling circuit; 121c-Second coupling circuit; 121d-Power supply circuit; 121e-First indicator circuit; 121f-Second indicator circuit; 121g-Second crystal oscillator circuit; 122-Processor. Detailed Implementation

[0018] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.

[0019] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in this application's specification means the presence of the stated integers, steps, elements, and / or components, but does not exclude implementations of other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by this art. It should be understood that when we say an element is "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element, or it may mean that the element and the other element are connected through an intermediate element. Furthermore, "connected" or "coupled" as used herein may include wireless connections or wireless coupling. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" may be implemented as "A," or as "B," or as "A and B."

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0021] With the continuous development of IoT technology, more and more smart devices are being applied in various fields, such as transportation, healthcare, and supermarkets. These smart devices require battery management systems to manage the battery and maintain normal operation. In related technologies, the various components within a battery management system are typically connected via complex wiring harnesses and connectors to achieve signal acquisition and transmission.

[0022] However, existing wired connection methods suffer from problems such as numerous connection points, complex structures, aging wire harnesses, and loose or detached connectors, resulting in poor system stability and high maintenance costs.

[0023] The technical solution of this application and how it solves the above-mentioned technical problems are described in detail below with specific embodiments. It should be noted that the following embodiments can be referenced, borrowed, or combined with each other, and the same terms, similar features, and similar implementation steps in different embodiments will not be described again.

[0024] This application provides a battery management system for managing battery packs, such as... Figure 1 As shown, the battery management system includes a data acquisition unit 11 and a main control board 12.

[0025] At least two acquisition units 11 are provided, and any two adjacent acquisition units 11 are wirelessly connected. Each acquisition unit 11 is configured to be electrically connected to at least two batteries in the battery pack in a one-to-one correspondence, and is used to collect battery performance information of each battery.

[0026] The main control board 12 is wirelessly connected to each acquisition unit 11 to receive battery performance information sent by the acquisition unit 11, and generates control information based on the battery performance information. The control information is used to control the battery pack.

[0027] The battery performance information of each battery is collected by the acquisition unit 11. The main control board 12 receives the battery performance information sent by the acquisition unit 11 and generates control information based on the battery performance information. This enables precise monitoring and control of the charging and discharging status of each battery in the battery pack, thereby improving the safety of battery use.

[0028] Furthermore, through wireless communication between any two adjacent acquisition units 11, the main control board 12 is wirelessly connected to each acquisition unit 11, which can reduce the number of connection harnesses and connectors in the battery management system. This not only makes the circuit structure of the battery management system simple, stable, and easy to maintain, but also avoids electrical isolation problems that may be caused by traditional wired connection methods, thereby improving the overall stability and reliability of the system.

[0029] In addition, through wireless communication between adjacent acquisition units, independently sampled batteries (cells) can be transformed into a distributed battery system (i.e., battery pack) that can be synchronized, redundant, and coordinated. The specific functions of wireless communication between adjacent acquisition units include: when any path is disconnected (e.g., the communication link between the i-th acquisition unit and the main control board), neighboring nodes (i.e., the i+1-th acquisition unit) can forward the data, ensuring that the data reaches the main control board and realizing data relay; broadcasting sampling trigger frames, enabling all acquisition units to latch voltage / current at the same time, eliminating phase errors and realizing synchronous sampling; high-voltage units can directly request neighbors to absorb energy, reducing the computation and bus load of the main control board and realizing local balanced cooperation; when an acquisition unit detects an abnormal battery, it broadcasts a fault code to both sides within milliseconds, and adjacent acquisition units synchronously disconnect the MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) to prevent energy backflow and realize fault cascading suppression; in the Mesh network, if any node fails, the neighbor automatically reroutes, improving system robustness and enabling topology self-healing; and unifying the RTC (Real-Time Clock) and ADC (Analog-to-Digital Converter) references through wireless synchronization frames to avoid accumulated errors and realize clock / calibration synchronization.

[0030] It should be noted that, Figure 1 The example uses three acquisition units 11, but in actual applications, the number of acquisition units 11 can be flexibly adjusted according to the number of batteries in the battery pack.

[0031] See Figure 2 In some embodiments, the acquisition unit 11 includes a near-field communication module, which includes a near-field communication chip and an antenna resonant circuit 111 electrically connected. The near-field communication chip is configured to interact with adjacent acquisition units 11 or main control board 12 in a non-contact manner through the antenna resonant circuit 111.

[0032] The near-field communication module, also known as the NFC module, is configured to interact with adjacent acquisition units 11 or main control boards 12 in a contactless manner via antenna resonant circuit 111, thereby enabling low-power, high-efficiency communication connections.

[0033] Figure 2 In the diagram, U1 represents the near-field communication chip.

[0034] See Figure 2 In some embodiments, the antenna resonant circuit 111 includes a first inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, and a first resistor.

[0035] The first terminal of the first inductor, the first terminal of the first capacitor, and the first terminal of the third capacitor are electrically connected to the first node.

[0036] The second terminal of the first inductor, the first terminal of the second capacitor, and the first terminal of the fourth capacitor are electrically connected to the second node.

[0037] The first end of the first resistor is electrically connected to the second end of the first capacitor, and the second end of the first resistor is electrically connected to the second end of the second capacitor.

[0038] The first differential antenna port of the near-field communication chip is electrically connected to the second terminal of the third capacitor, and the second differential antenna port of the near-field communication chip is electrically connected to the second terminal of the fourth capacitor.

[0039] Figure 2 In the diagram, C1 represents the first capacitor, C2 represents the second capacitor, C3 represents the third capacitor, C4 represents the fourth capacitor, L1 represents the first inductor, and R1 represents the first resistor.

[0040] Figure 2 In the diagram, PIN35 of the near-field communication chip U1 represents the first differential antenna port, and PIN36 of the near-field communication chip U1 represents the second differential antenna port.

[0041] The first inductor L1 serves as the antenna coil body, used to generate magnetic flux. The first capacitor C1 and the second capacitor C2 form a series voltage divider capacitor, and the third capacitor C3 and the fourth capacitor C4 form a differential matching capacitor. C1-C4 together precisely lock the resonance at 13.56 MHz and complete the differential matching. The first resistor R1 serves as a Q-factor (Quality Factor) damping resistor, used to suppress excessively high peak impedance of the antenna resonant circuit 111 in the operating frequency band.

[0042] This configuration effectively enhances the communication performance of the near-field communication module, enabling it to maintain stable data transmission capabilities even in complex electromagnetic environments. Furthermore, it optimizes communication distance and angular sensitivity, thereby improving system compatibility and practicality.

[0043] See Figure 2 In some embodiments, the near-field communication module further includes a first crystal oscillator circuit 117; the first crystal oscillator circuit 117 includes a crystal element, a seventeenth capacitor, an eighteenth capacitor, and a feedback resistor.

[0044] The first terminal of the crystal oscillator, the first terminal of the seventeenth capacitor, and the first terminal of the feedback resistor are electrically connected to the crystal oscillator input node.

[0045] The second terminal of the crystal oscillator, the first terminal of the eighteenth capacitor, and the second terminal of the feedback resistor are electrically connected to the crystal oscillator output node; the second terminals of the seventeenth capacitor and the eighteenth capacitor are both grounded.

[0046] The clock input terminal of the near-field communication chip is electrically connected to the crystal oscillator input node, and the clock output terminal of the near-field communication chip is electrically connected to the crystal oscillator output node.

[0047] Figure 2 In the diagram, Y1 represents the crystal oscillator, C17 represents the seventeenth capacitor, C18 represents the eighteenth capacitor, and R3 represents the feedback resistor.

[0048] Figure 2 In the near-field communication chip U1, PIN38 represents the clock input terminal, and PIN39 represents the clock output terminal.

[0049] The first crystal oscillator circuit 117 provides a stable operating clock for the near-field communication chip, ensuring the accuracy and timing stability of data transmission. By appropriately selecting the crystal oscillator frequency and capacitor parameters, the response characteristics of the chip's internal phase-locked loop (PLL) can be optimized, thereby improving the anti-interference capability and transmission efficiency of communication.

[0050] In addition, the setting of feedback resistor R2 helps to stabilize the start-up process of the first crystal oscillator circuit 117, avoid clock signal jitter caused by external electromagnetic interference, and thus further improve the operational stability of the near-field communication chip.

[0051] By connecting the crystal oscillator's input and output nodes to the clock input and output terminals of the near-field communication (NFC) chip, respectively, high-precision clock synchronization can be achieved. This design not only ensures the reliability of the NFC module in high-speed data transmission but also enhances its adaptability to complex electromagnetic environments.

[0052] See Figure 2 In some embodiments, the acquisition unit 11 further includes a voltage acquisition circuit 112; the voltage acquisition circuit 112 includes a first fuse element, a second fuse element, a fifth capacitor, a sixth capacitor, and a seventh capacitor.

[0053] The first terminal of the first fuse element and the first terminal of the second fuse element are both configured to be electrically connected to the positive terminal of the battery.

[0054] The first power input terminal of the near-field communication chip, the second terminal of the first fuse element, the first terminal of the sixth capacitor, and the first terminal of the seventh capacitor are all configured to be electrically connected to the positive terminal of the power supply; the second terminal of the sixth capacitor and the second terminal of the seventh capacitor are both grounded.

[0055] The second power input terminal of the near-field communication chip and the second terminal of the second fuse element are both electrically connected to the first terminal of the fifth capacitor, and the second terminal of the fifth capacitor is grounded; the first terminal of the first voltage divider resistor is electrically connected to the second terminal of the second fuse element.

[0056] Figure 2 In the diagram, F1 represents the first fuse, F2 represents the second fuse, C5 represents the fifth capacitor, C6 represents the sixth capacitor, and C7 represents the seventh capacitor.

[0057] Figure 2 In the near field communication chip U1, PIN1 represents the first power input terminal, and PIN2 represents the second power input terminal.

[0058] The voltage acquisition circuit 112 is used to acquire the battery voltage and power the chip. The main control board determines the remaining battery power based on the battery voltage acquired by the voltage acquisition circuit 112, so as to control each battery and prevent overcharging or over-discharging.

[0059] By setting a first fuse and a second fuse, dual protection can be provided in the event of voltage overload or short circuit, preventing circuit damage.

[0060] The fifth, sixth, and seventh capacitors are used to filter out high-frequency noise from the power supply, stabilize the chip's power supply voltage, and improve the stability and reliability of the system.

[0061] See Figure 2 In some embodiments, the acquisition unit 11 further includes a current acquisition circuit 113; the current acquisition circuit 113 includes a shunt and an eighth capacitor.

[0062] The current detection input terminal of the near-field communication chip, the first terminal of the shunt, and the first terminal of the eighth capacitor are electrically connected to the positive terminal node of the current detection.

[0063] The current detection output terminal of the near-field communication chip, the second terminal of the shunt, and the second terminal of the eighth capacitor are electrically connected to the negative terminal node of the current detection.

[0064] The positive and negative terminals of the current sensing are electrically connected to the two ends of the battery's power path, respectively.

[0065] Figure 2 In the diagram, VSHUNT represents the shunt, and C8 represents the eighth capacitor.

[0066] Figure 2 In the diagram, PIN7 of the near-field communication chip U1 represents the current detection input terminal, and PIN6 of the near-field communication chip U1 represents the current detection output terminal.

[0067] Since the positive and negative terminals of the current detection are electrically connected to the two ends of the power path of the battery, the main current of the cell flows through the shunt VSHUNT, so that the near-field communication chip U1 obtains the cell (battery) current signal through the differential sampling circuit formed by the shunt VSHUNT and the eighth capacitor C8.

[0068] The battery charging and discharging current is accurately sampled by a shunt, and the sampled signal is filtered by an eighth capacitor, thereby improving the accuracy and stability of current detection.

[0069] The main control board monitors the battery status in real time based on the charging and discharging current data acquired by the current acquisition circuit 113. Combined with the data provided by the voltage acquisition circuit 112, it can accurately calculate the remaining battery capacity and health status. This design effectively enhances the battery management system's control over battery performance, ensuring the safe and efficient use of the battery.

[0070] See Figure 2 In some embodiments, the acquisition unit 11 further includes at least one temperature acquisition circuit; the temperature acquisition circuit includes a temperature sensor and a bypass capacitor.

[0071] The first terminal of the temperature sensor and the first terminal of the bypass capacitor are both electrically connected to the temperature input terminal of the near-field communication chip; the second terminal of the temperature sensor and the second terminal of the bypass capacitor are both grounded.

[0072] The first end of the temperature sensor is configured to contact the temperature detection point of the battery.

[0073] See Figure 2 In this embodiment, the acquisition unit 11 includes two temperature acquisition circuits, namely the first temperature acquisition circuit 114 and the second temperature acquisition circuit 115. It should be noted that the number of temperature acquisition circuits can also be one, three or more, and is not limited here.

[0074] Figure 2 In the diagram, RT1 represents the temperature sensor of the first temperature acquisition circuit 114, and C9 represents the bypass capacitor of the first temperature acquisition circuit 114; RT1 represents the temperature sensor of the second temperature acquisition circuit 115, and C10 represents the bypass capacitor of the second temperature acquisition circuit 115.

[0075] Figure 2 In the near-field communication chip U1, PIN8 represents one temperature input terminal, and PIN9 represents another temperature input terminal.

[0076] By using two temperature acquisition circuits to detect the temperature at different locations on the battery, more comprehensive thermal state information of the battery can be obtained, improving the accuracy and reliability of temperature monitoring.

[0077] Temperature sensors can employ negative temperature coefficient thermistors, which can convert battery temperature information into electrical signals, and the signals are filtered by bypass capacitors to improve temperature detection accuracy.

[0078] The main control board collects temperature data from multiple temperature acquisition circuits and combines this data with current and voltage information to comprehensively determine the battery's thermal management status. During battery charging and discharging, if an abnormal temperature or excessive temperature difference is detected, the system can promptly trigger a protection mechanism to prevent the battery from overheating and causing safety risks.

[0079] See Figure 2 In some embodiments, the acquisition unit 11 further includes a passive equalization circuit 116: the passive equalization circuit 116 includes a field-effect transistor and a second resistor.

[0080] The gate of the field-effect transistor and the first terminal of the second resistor are both electrically connected to the equalization control terminal of the near-field communication chip.

[0081] The source of the field-effect transistor and the second terminal of the second resistor are both configured to be electrically connected to the negative terminal of the battery.

[0082] The drain of the field-effect transistor is configured to be electrically connected to the positive terminal of the battery.

[0083] Figure 2 In the diagram, Q1 represents the field-effect transistor, and R2 represents the second resistor.

[0084] Figure 2 In the near-field communication chip U1, PIN13 represents the equalization control terminal.

[0085] When the near-field communication chip U1 outputs a high level through the equalization control terminal, the field-effect transistor Q1 is turned on. The energy of the cell forms a bypass discharge circuit through the field-effect transistor Q1, the second resistor R2 and the negative terminal of the cell (battery). The excess energy of the cell with higher charge is dissipated in the form of heat, so that the voltage / capacity of the cell is aligned with the lowest cell in the whole group, thus achieving voltage / capacity balance.

[0086] See also Figure 2 Optionally, the acquisition unit 11 also includes a reverse diode electrically connected between the positive and negative terminals of the battery. That is, the cathode of the reverse diode is electrically connected to the positive terminal BAT+ of the battery cell, and the anode is electrically connected to the negative terminal BAT- of the battery cell, so as to provide bypass protection when the battery cell is reverse connected.

[0087] Figure 2 In the diagram, D1 represents the reverse diode.

[0088] See Figure 3 In some embodiments, the main control board 12 includes a radio manager 121 and a processor 122.

[0089] The radio manager 121 communicates wirelessly with the acquisition unit 11 to receive battery performance information sent by the acquisition unit 11. The processor 122 is electrically connected to the radio manager 121 via a serial bus and is used to receive battery performance information transmitted by the radio manager 121, and to monitor and control the charging and discharging status of the battery pack based on the battery performance information.

[0090] Battery performance information includes, but is not limited to, parameters such as battery voltage, battery current, battery temperature, and battery internal resistance.

[0091] The processor 122 is used to determine whether the battery pack is in an abnormal state of overvoltage, undervoltage, overcurrent or temperature based on the received battery performance information, and generates a control signal to adjust the working state of the charging and discharging circuit when an abnormality is detected, thereby ensuring the safe operation of the battery pack.

[0092] See Figure 4 In some embodiments, the radio manager 121 includes a radio frequency communication module; the radio frequency communication module includes a radio frequency chip, a matching circuit 121a, a first antenna, and a second antenna.

[0093] The matching circuit 121a includes a second inductor, a fourth inductor, a nineteenth capacitor, a twentieth capacitor, a twenty-second capacitor, and a twenty-third capacitor.

[0094] The first terminal of the second inductor and the first terminal of the fourth inductor are electrically connected.

[0095] The second terminal of the second inductor, the first terminal of the nineteenth capacitor, and the first terminal of the twentieth capacitor are electrically connected to the third node; the second terminal of the twentieth capacitor is electrically connected to the first differential antenna port of the RF chip; and the second terminal of the nineteenth capacitor is coupled to the first antenna.

[0096] The second terminal of the fourth inductor, the first terminal of the twenty-second capacitor, and the first terminal of the twenty-third capacitor are electrically connected to the fourth node; the second terminal of the twenty-third capacitor is electrically connected to the second differential antenna port of the RF chip; and the second terminal of the twenty-second capacitor is coupled to the second antenna.

[0097] Figure 4 In the diagram, U2 represents the RF chip, J2 represents the first antenna, and J1 represents the second antenna. L2 represents the second inductor, L4 represents the fourth inductor, C19 represents the nineteenth capacitor, C20 represents the twentieth capacitor, C22 represents the twenty-second capacitor, and C23 represents the twenty-third capacitor.

[0098] Figure 4 In the diagram, PIN42 of RF chip U2 represents the first differential antenna port, and PIN41 of RF chip U2 represents the second differential antenna port.

[0099] In this embodiment, the radio frequency chip U2 can also be an NFC chip (i.e., a near field communication chip), meaning that the acquisition unit 11 and the radio manager 121 communicate via NFC.

[0100] The matching circuit 121a described above achieves impedance matching between the RF chip and the antenna by properly configuring the inductor and capacitor parameters, thereby ensuring the efficiency and stability of signal transmission.

[0101] By adjusting the inductance values ​​of the second and fourth inductors and the capacitance values ​​of each capacitor, the output impedance of the RF chip and the input impedance of the antenna can be made to achieve a conjugate matching state, effectively reducing signal reflection and loss.

[0102] See Figure 4 In some embodiments, the radio frequency communication module further includes a first coupling circuit 121b; the first coupling circuit 121b includes a thirty-first capacitor, a seventh resistor, a seventh inductor, a forty-third capacitor, and a forty-fourth capacitor.

[0103] The first terminal of the 31st capacitor is electrically connected to the second terminal of the 19th capacitor; the second terminal of the 31st capacitor is electrically connected to the first terminal of the 7th resistor; the second terminal of the 7th resistor, the first terminal of the 7th inductor, and the first terminal of the 44th capacitor are electrically connected to the 5th node; the second terminal of the 7th inductor, the first terminal of the 43rd capacitor, and the first terminal of the 1st antenna are electrically connected to the 6th node; the second terminals of the 44th capacitor, the 43rd capacitor, and the 1st antenna are all grounded.

[0104] See Figure 4 In some embodiments, the radio frequency communication module further includes a second coupling circuit 121c; the second coupling circuit 121c includes a twenty-first capacitor, a third inductor, a fifth inductor, a forty-first capacitor, and a forty-second capacitor.

[0105] The first terminal of the 21st capacitor is electrically connected to the second terminal of the 22nd capacitor. The second terminal of the 21st capacitor, the first terminal of the 3rd inductor, and the first terminal of the 41st capacitor are electrically connected to the 7th node. The second terminal of the 3rd inductor, the first terminal of the 5th inductor, the first terminal of the 42nd capacitor, and the first terminal of the 2nd antenna are electrically connected to the 8th node. The second terminal of the 5th inductor, the second terminal of the 41st capacitor, the second terminal of the 42nd capacitor, and the second terminal of the 2nd antenna are all grounded.

[0106] Optionally, the first and second antennas of the main control board 12 are NFC antennas.

[0107] In other words, by using two sets of symmetrical π-type / L-type matching networks, the first differential antenna port and the second differential antenna port of the RF chip U2 are respectively connected to the second antenna J1 and the first antenna J2 to achieve 13.56 MHz near-field communication.

[0108] See Figure 4 For the matching network from the first differential antenna port PIN42 of RF chip U2 to the first antenna J2: the twentieth capacitor C20, the second inductor L2, and the nineteenth capacitor C19 form a π network to complete impedance transformation. The thirty-first capacitor C31, the seventh resistor R7, and the seventh inductor L7 form an additional L-type network. The thirty-first capacitor C31 further blocks DC, the seventh resistor R7 is a damping resistor used to suppress overshoot, and the seventh inductor L7 performs the final matching stage and couples to the first antenna J2.

[0109] For the matching network from the second differential antenna port PIN41 of RF chip U2 to the second antenna J1: the twenty-third capacitor C23 and the fourth inductor L4 form an L-type network, providing initial impedance matching. The twenty-second capacitor C22, the third inductor L3, and the twenty-first capacitor C21 form a π-type network, which blocks DC through the twenty-second capacitor C22 and the second capacitor C21, and couples to the second antenna J1 through the third inductor L3. By properly configuring the capacitor and inductor parameters in the above π-type and L-type matching networks, The two sets of symmetrically designed matching networks effectively ensure the conjugate matching between the differential antenna port of the RF chip and the NFC antenna, further reducing signal reflection loss and improving communication stability and efficiency.

[0110] As an example, the wireless communication process (zero cable) between the acquisition unit 11 and the main control board 12 includes: 1. Proximity Trigger: When the distance between the near-field communication module of the acquisition unit 11 and the NFC antenna (or conformal antenna) of the main control board 12 is ≤ 2 cm, the antenna resonant circuit 111 of the near-field communication module generates an induced current, activating the NFC front-end of both parties.

[0111] 2. NFC Data Exchange: The near-field communication chip U1 of the near-field communication module of the acquisition unit 11 transmits the "connection token" (Wi-Fi SSID / password, Bluetooth MAC, pairing key or WPS PIN) to the radio frequency chip U2 of the radio manager 121 of the main control board 12 in one go via ISO14443 / ISO18092 frame format.

[0112] 3. Radio Manager 121 Takeover: The processor 122 on the main control board 12 tells the radio manager 121 via the internal bus, "Token verified, immediately enable Wi-Fi Soft-AP or Bluetooth Peripheral mode." This step does not require the participation of the near-field communication module of the acquisition unit 11 and is completed entirely autonomously by the main control board 12.

[0113] 4. Establish a high-speed wireless link: The acquisition unit 11 uses the newly acquired connection information to establish a persistent data channel with the main control board 12 via 2.4 GHz Wi-Fi or Bluetooth to enable subsequent large-scale data interaction.

[0114] See Figure 4In some embodiments, the radio manager 121 further includes a power supply circuit 121d for powering the RF chip U2. The power supply circuit 121d includes a 25th capacitor C25 and a 24th capacitor C24; the two power supply pins PIN1 / PIN2 of the RF chip U2 are electrically connected to one end of the 25th capacitor C25 and the 24th capacitor C24, respectively, and the other pins of the 25th capacitor C25 and the 24th capacitor C24 are both grounded to GND.

[0115] See Figure 4 In some embodiments, PIN4 of RF chip U2 is grounded to GND; PIN8 / PIN7 / PIN57 of RF chip U2 are all grounded to GND.

[0116] See Figure 4 In some embodiments, the radio manager 121 further includes an indication circuit for indicating the communication status. There may be two indication circuits, namely a first indication circuit 121e and a second indication circuit 121f.

[0117] The first indicator circuit 121e includes a second light-emitting diode DS2 and a tenth resistor R10. PIN49 of the RF chip U2 is connected to the cathode of the second light-emitting diode DS2, the anode of the second light-emitting diode DS2 is connected to one end of the tenth resistor R10, and the other end of the tenth resistor R10 is connected to a power supply (e.g., 5V).

[0118] The second indicator circuit 121f includes a first light-emitting diode DS1 and a ninth resistor R9. PIN50 of the RF chip U2 is connected to the cathode of the first light-emitting diode DS1, the anode of the first light-emitting diode DS1 is connected to one end of the ninth resistor R9, and the other end of the ninth resistor R9 is connected to a power supply (e.g., 5V).

[0119] See Figure 4 In some embodiments, the radio manager 121 further includes a second crystal oscillator circuit 121g for generating and stabilizing a clock signal of a specific frequency. The second crystal oscillator circuit 121g includes a second crystal element Y2, a twelfth resistor R12, a thirty-second capacitor C32, and a thirty-third capacitor C33. PIN 45 of the RF chip U2 is connected to one end of the twelfth resistor R12, the second crystal element Y2, and the thirty-second capacitor C32, respectively, with the other end of the thirty-second capacitor C32 grounded (GND). PIN 46 of the RF chip U2 is connected to the other end of the twelfth resistor R12, the other end of the second crystal element Y2, and one end of the thirty-third capacitor C33, with the other end of the thirty-third capacitor C33 grounded (GND).

[0120] See Figure 4In some embodiments, the radio manager 121 also includes at least one decoupling capacitor to prevent interference to the pins of the RF chip U2. The decoupling capacitor may include capacitors C34, C35, C36, C37, C38, and C39. PIN5 of RF chip U2 is connected to one end of capacitor C34 (the 34th capacitor), and the other end of capacitor C34 is grounded (GND). PIN6 of RF chip U2 is connected to one end of capacitor C35 (the 35th capacitor), and the other end of capacitor C35 is grounded (GND). PIN23 of RF chip U2 is connected to one end of capacitor C36 (the 36th capacitor), thus outputting a 1.2V voltage. The other end of capacitor C36 is grounded (GND). PIN34 of RF chip U2 is connected to one end of capacitor C37 (the 37th capacitor), and the other end of capacitor C37 is grounded (GND). PIN35 of RF chip U2 is connected to one end of capacitor C38 (the 38th capacitor), thus outputting a 1.8V voltage. The other end of capacitor C38 is grounded (GND). PIN44 and PIN47 of RF chip U2 are connected to one end of capacitor C39 (the 39th capacitor), and the other end of capacitor C39 is grounded (GND).

[0121] The beneficial technical effects of the technical solutions provided in this application include: The battery performance information of each battery is collected by the acquisition unit 11. The main control board 12 receives the battery performance information sent by the acquisition unit 11 and generates control information based on the battery performance information. This enables precise monitoring and control of the charging and discharging status of each battery in the battery pack, thereby improving the safety of battery use.

[0122] Furthermore, through wireless communication between any two adjacent acquisition units 11, the main control board 12 is wirelessly connected to each acquisition unit 11, which can reduce the number of connection harnesses and connectors in the battery management system. This not only makes the circuit structure of the battery management system simple, stable, and easy to maintain, but also avoids electrical isolation problems that may be caused by traditional wired connection methods, thereby improving the overall stability and reliability of the system.

[0123] Those skilled in the art will understand that the steps, measures, and solutions in the various operations, methods, and processes discussed in this application can be alternated, modified, combined, or deleted. Furthermore, other steps, measures, and solutions in the various operations, methods, and processes discussed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted. Furthermore, steps, measures, and solutions in related technologies that are similar to those disclosed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0124] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0125] The above description is only a partial implementation of this application. It should be noted that for those skilled in the art, other similar implementation methods based on the technical concept of this application, without departing from the technical concept of this application, also fall within the protection scope of the embodiments of this application.

Claims

1. A battery management system for managing a battery pack, characterized in that, include: The acquisition unit is provided with at least two, and any two adjacent acquisition units are wirelessly connected. Each acquisition unit is configured to be electrically connected to at least two batteries in the battery pack in a one-to-one correspondence, and is used to acquire battery performance information of each battery. The main control board is wirelessly connected to each of the acquisition units and is used to receive the battery performance information sent by the acquisition units, generate control information based on the battery performance information, and control the battery pack.

2. The battery management system according to claim 1, characterized in that, The acquisition unit includes a near-field communication module, which includes a near-field communication chip and an antenna resonant circuit that are electrically connected. The near-field communication chip is configured to interact with adjacent acquisition units or the main control board in a non-contact manner through the antenna resonant circuit.

3. The battery management system according to claim 2, characterized in that, The antenna resonant circuit includes a first inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, and a first resistor; The first terminal of the first inductor, the first terminal of the first capacitor, and the first terminal of the third capacitor are electrically connected to the first node. The second terminal of the first inductor, the first terminal of the second capacitor, and the first terminal of the fourth capacitor are electrically connected to the second node. The first end of the first resistor is electrically connected to the second end of the first capacitor, and the second end of the first resistor is electrically connected to the second end of the second capacitor. The first differential antenna port of the near-field communication chip is electrically connected to the second terminal of the third capacitor, and the second differential antenna port of the near-field communication chip is electrically connected to the second terminal of the fourth capacitor.

4. The battery management system according to claim 2, characterized in that, The acquisition unit also includes a voltage acquisition circuit; The voltage acquisition circuit includes a first fuse element, a second fuse element, a fifth capacitor, a sixth capacitor, and a seventh capacitor; The first end of the first fuse element and the first end of the second fuse element are both configured to be electrically connected to the positive terminal of the battery. The first power input terminal of the near-field communication chip, the second terminal of the first fuse element, the first terminal of the sixth capacitor, and the first terminal of the seventh capacitor are all configured to be electrically connected to the positive terminal of the power supply; the second terminal of the sixth capacitor and the second terminal of the seventh capacitor are both grounded. The second power input terminal of the near-field communication chip and the second terminal of the second fuse element are both electrically connected to the first terminal of the fifth capacitor, and the second terminal of the fifth capacitor is grounded; the first terminal of the first voltage divider resistor is electrically connected to the second terminal of the second fuse element.

5. The battery management system according to claim 2, characterized in that, The acquisition unit also includes a current acquisition circuit; The current acquisition circuit includes a shunt and an eighth capacitor; The current detection input terminal of the near-field communication chip, the first end of the shunt and the first end of the eighth capacitor are electrically connected to the current detection positive terminal node. The current detection output terminal of the near-field communication chip, the second terminal of the shunt, and the second terminal of the eighth capacitor are electrically connected to the negative terminal node of the current detection. The positive current detection node and the negative current detection node are electrically connected to both ends of the power path of the battery, respectively.

6. The battery management system according to claim 2, characterized in that, The acquisition unit also includes at least one temperature acquisition circuit; The temperature acquisition circuit includes a temperature sensor and a bypass capacitor; The first terminal of the temperature sensor and the first terminal of the bypass capacitor are both electrically connected to the temperature input terminal of the near-field communication chip; the second terminal of the temperature sensor and the second terminal of the bypass capacitor are both grounded. The first end of the temperature sensor is configured to contact the temperature detection point of the battery.

7. The battery management system according to claim 2, characterized in that, The acquisition unit also includes a passive equalization circuit: The passive equalization circuit includes a field-effect transistor and a second resistor; The gate of the field-effect transistor and the first terminal of the second resistor are both electrically connected to the equalization control terminal of the near-field communication chip. The source of the field-effect transistor and the second terminal of the second resistor are both configured to be electrically connected to the negative terminal of the battery. The drain of the field-effect transistor is configured to be electrically connected to the positive terminal of the battery.

8. The battery management system according to claim 1, characterized in that, The main control board includes: A radio manager communicates wirelessly with the acquisition unit to receive the battery performance information sent by the acquisition unit. The processor is electrically connected to the radio manager via a serial bus and is used to receive the battery performance information transmitted by the radio manager, and to monitor and control the charging and discharging status of the battery pack based on the battery performance information.

9. The battery management system according to claim 8, characterized in that, The radio manager includes a radio frequency communication module; The radio frequency communication module includes a radio frequency chip, a matching circuit, a first antenna, and a second antenna; The matching circuit includes a second inductor, a fourth inductor, a nineteenth capacitor, a twentieth capacitor, a twenty-second capacitor, and a twenty-third capacitor. The first terminal of the second inductor and the first terminal of the fourth inductor are electrically connected; The second terminal of the second inductor, the first terminal of the nineteenth capacitor, and the first terminal of the twentieth capacitor are electrically connected to the third node; the second terminal of the twentieth capacitor is electrically connected to the first differential antenna port of the RF chip; the second terminal of the nineteenth capacitor is coupled to the first antenna. The second terminal of the fourth inductor, the first terminal of the twenty-second capacitor, and the first terminal of the twenty-third capacitor are electrically connected to the fourth node; the second terminal of the twenty-third capacitor is electrically connected to the second differential antenna port of the RF chip; and the second terminal of the twenty-second capacitor is coupled to the second antenna.

10. The battery management system according to claim 9, characterized in that, The radio frequency communication module further includes a first coupling circuit; The first coupling circuit includes a thirty-first capacitor, a seventh resistor, a seventh inductor, a forty-third capacitor, and a forty-fourth capacitor; the first terminal of the thirty-first capacitor is electrically connected to the second terminal of the nineteenth capacitor; the second terminal of the thirty-first capacitor is electrically connected to the first terminal of the seventh resistor; the second terminal of the seventh resistor, the first terminal of the seventh inductor, and the first terminal of the forty-fourth capacitor are electrically connected to the fifth node; the second terminal of the seventh inductor, the first terminal of the forty-third capacitor, and the first terminal of the first antenna are electrically connected to the sixth node; the second terminals of the forty-fourth capacitor, the forty-third capacitor, and the first antenna are all grounded.

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