A lithium iron phosphate semi-solid battery pack management circuit and system

Abstract

The application discloses a lithium iron phosphate semi-solid battery pack management circuit and system, which comprises an electric core module, a battery management unit, a wireless connection unit and an antenna circuit. The antenna circuit comprises a wireless communication module, which is electrically connected with the wireless connection unit and is provided with a radio frequency output end; an impedance matching network, which comprises at least one inductive element and at least one capacitive element; a filter branch, which is connected with the output end of the impedance matching network; and an antenna main body, which is connected with the output end of the filter branch and is arranged at the side edge area of a circuit board. A clearance isolation area is arranged around the antenna main body, and an isolation structure is arranged between the communication area where the antenna main body is located and the power area where the power loop in the battery pack is located. Through the collaborative design of impedance matching, filter noise suppression and the partition isolation of the communication area and the power area on the antenna circuit, the wireless transmission stability of the battery pack in a complex internal electromagnetic environment is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a lithium iron phosphate semi-solid-state battery pack management circuit and system. Background Technology

[0002] With the continuous development of new energy storage, electric vehicles, portable high-power devices, emergency power supplies, and intelligent backup power systems, battery packs are gradually evolving towards higher energy density, higher safety, and intelligent management. In particular, lithium iron phosphate semi-solid-state battery packs combine the high thermal stability of the lithium iron phosphate system with the comprehensive advantages of semi-solid-state systems in terms of safety, cycle life, and electrochemical performance. They are increasingly being used in residential and commercial energy storage, power backup, low-speed power equipment, special mobile power supplies, and intelligent power systems requiring remote status monitoring. In these application scenarios, to facilitate real-time access to the battery pack's operating status, fault information, and parameter settings by users or maintenance terminals, related products typically integrate wireless communication functions on top of the battery management system to achieve short-range wireless reading and interaction of battery operating data.

[0003] In existing technologies, a battery management unit is typically placed within the battery pack management circuit, and a wireless communication module is directly mounted on the circuit board. An antenna is then used to transmit and receive wireless signals, thus enabling wireless transmission of battery information. However, because the battery pack contains power circuits, conductive components, and charge / discharge switching devices, electromagnetic interference is easily generated in the power circuits during charging, discharging, and current fluctuations. This interference can affect the wireless communication link through feeders, grounding, or spatial coupling, leading to unstable wireless signal transmission and reception and decreased communication reliability.

[0004] In other words, existing technologies focus more on the implementation of wireless connectivity itself, while giving insufficient consideration to the stability of wireless communication design, making it difficult to guarantee the stable wireless transmission performance of the battery pack in the complex internal electromagnetic environment. Summary of the Invention

[0005] The purpose of this invention is to provide a lithium iron phosphate semi-solid-state battery pack management circuit and system to solve the above-mentioned technical problems.

[0006] To achieve this objective, the present invention adopts the following technical solution: A lithium iron phosphate semi-solid-state battery pack management circuit includes: Battery cell module; A battery management unit, electrically connected to the battery cell module, is used to collect the operating parameters of the battery cell module; A wireless connection unit is mounted on a circuit board and is electrically connected to the battery management unit; Antenna circuit, the antenna circuit comprising: A wireless communication module is electrically connected to the wireless connection unit, and the wireless communication module is provided with a radio frequency output terminal; An impedance matching network, the input of which is connected to the radio frequency output of the wireless communication module, the impedance matching network including at least one inductor and at least one capacitor. A filter branch, the input of which is connected to the output of the impedance matching network, includes a ferrite bead connected in series on the feed line and a bypass capacitor connected in parallel to the communication reference ground. The antenna body is connected to the output terminal of the filter branch, and the antenna body is disposed in the side edge area of ​​the circuit board; The antenna body is surrounded by a clearance isolation zone, and an isolation structure is provided between the communication area where the antenna body is located and the power area where the power circuit in the battery pack is located.

[0007] Optionally, the lithium iron phosphate semi-solid-state battery pack management circuit further includes: The power supply unit has its input terminal connected to the battery cell module and its output terminal connected to the battery management unit and the wireless communication module, respectively. The power supply unit includes a voltage regulator and filter capacitors disposed on the input and output sides of the voltage regulator.

[0008] Optionally, the battery management unit includes: The main control unit has its input terminal connected to the positive and negative terminals of each cell in the cell module, and its output terminal connected to the control terminal of the switching transistor in the power circuit. The analog front end is provided with multiple voltage sampling input terminals and temperature sampling input terminals. The temperature sampling input terminals are connected to a temperature sensor disposed on the battery cell module. The analog front end is connected to the main control unit through a serial peripheral interface or an integrated circuit bus.

[0009] Optionally, the power circuit includes a charging switch and a discharging switch connected in series with the positive or negative terminal of the cell module output, and a sampling resistor connected in series in the power circuit, the two ends of which are connected to the battery management unit.

[0010] Optionally, both the charging switch and the discharging switch are MOSFETs, and the charging switch and the discharging switch are connected in series back to back, with their sources or drains connected together. The sampling resistor is positioned between the negative output terminal of the battery cell module and the source of the discharge switch transistor, and the resistance value of the sampling resistor ranges from 0.1 milliohms to 5 milliohms.

[0011] Optionally, the antenna circuit further includes: The antenna feed terminal is located between the radio frequency output terminal of the wireless communication module and the impedance matching network; An ESD protection diode is connected in parallel between the antenna feed terminal and the communication reference ground.

[0012] Optionally, the impedance matching network includes a first matching capacitor, a matching inductor, and a second matching capacitor. One end of the first matching capacitor is connected to the antenna feed terminal, the other end of the first matching capacitor is connected to one end of the matching inductor, the other end of the matching inductor is connected to one end of the second matching capacitor, and the other end of the second matching capacitor is connected to the input terminal of the filter branch.

[0013] Optionally, the filtering branch includes a high-frequency ferrite bead connected in series on the feed line and a bypass capacitor connected in parallel to the communication reference ground. The high-frequency ferrite bead is disposed between the output terminal of the impedance matching network and the antenna body. One end of the bypass capacitor is connected to the node between the high-frequency ferrite bead and the antenna body, and the other end of the bypass capacitor is connected to the communication reference ground. The communication reference ground and the power reference ground corresponding to the power circuit are connected by a single point connection or a magnetic coupling connection.

[0014] Optionally, the isolation structure is a grounded conductive strip or a metal shield, disposed on the circuit board and located between the feed line side of the antenna body and the power circuit.

[0015] The present invention also provides a battery pack management system with stable wireless transmission capability, including a battery pack and a lithium iron phosphate semi-solid battery pack management circuit as described above.

[0016] Compared with the prior art, the present invention has the following beneficial effects: During operation, the cell module provides working power to the entire management circuit. The battery management unit is electrically connected to the cell module and collects operating parameters such as voltage, current, temperature, and state of charge of the cell module. The collected operating parameters are processed by the battery management unit and transmitted to the wireless connection unit, which then sends them to the wireless communication module Q1 in the antenna circuit. The wireless communication module Q1 converts the received data into radio frequency signals and outputs them to the impedance matching network from the radio frequency output terminal. After impedance tuning of the radio frequency signal, the impedance matching network sends the signal to the filtering branch. The filtering branch suppresses high-frequency interference through a ferrite bead connected in series on the feed line and discharges spurious noise through a bypass capacitor C3 connected in parallel to the communication reference ground G1. The antenna body then transmits the processed wireless signal outwards or receives wireless signals sent by external terminals and transmits them back to the wireless communication module Q1. Simultaneously, because the antenna body is located on the side edge of the circuit board and is surrounded by a clearance isolation area, and the communication area where the antenna body is located is separated from the power area where the power circuit within the battery pack is located by the isolation structure S1, electromagnetic coupling interference generated by the power circuit during charging, discharging, or current fluctuations can be reduced, ensuring stable wireless signal transmission and reception, and achieving stable wireless transmission of battery pack operating data. This solution significantly improves the wireless transmission stability of the battery pack in a complex internal electromagnetic environment through the coordinated design of impedance matching, filtering and noise suppression, and partitioning and isolating the communication and power areas of the antenna circuit. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0019] Figure 1 This is a schematic diagram of the main circuit of the lithium iron phosphate semi-solid-state battery pack management circuit in this embodiment.

[0020] Figure 2This is a schematic diagram of the antenna circuit of the lithium iron phosphate semi-solid battery pack management circuit in this embodiment. Detailed Implementation

[0021] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0022] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1: Combination Figure 1 and Figure 2 As shown, this embodiment of the invention provides a lithium iron phosphate semi-solid-state battery pack management circuit, including a cell module 10, a battery management unit 20, a wireless connection unit 30, and an antenna circuit 200. Cell module 10 is the basic energy storage unit of the battery pack corresponding to this management circuit. It is preferably composed of multiple lithium iron phosphate semi-solid cells connected in series or in parallel to form a battery system that meets the target voltage platform and capacity requirements. Here, lithium iron phosphate semi-solid cells can be understood as cell structures that use a lithium iron phosphate cathode system and are combined with a semi-solid electrolyte system or a gel / solid-liquid composite electrolyte system, thereby achieving a balance of high safety, cycle stability, and rate performance.

[0025] The battery management unit 20, electrically connected to the cell module 10, is used to collect the operating parameters of the cell module 10. The battery management unit 20, electrically connected to the cell module 10, is the core of the battery pack management circuit for monitoring and control. Its main function is to collect and process the operating parameters of the cell module 10, which may include individual cell voltage, total voltage, charging and discharging current, temperature, state of charge, health status, and abnormal alarm information. After acquiring the above parameters, the battery management unit 20 can perform status judgment, fault identification, and protection control according to preset strategies, and output the corresponding data to the wireless connection unit 30 for subsequent external transmission via the wireless communication link.

[0026] Preferably, the battery management unit 20 may include one or more of the following: a main control chip, an analog front-end sampling chip, a temperature sampling branch, and an equalization control branch, thereby realizing centralized management of the operating status of the semi-solid-state battery module 10.

[0027] The wireless connection unit 30 is disposed on the circuit board and electrically connected to the battery management unit 20. Its function is to establish an interaction channel between the battery management unit 20 and the subsequent antenna circuit 200. Preferably, the wireless connection unit 30 can employ a digital interface circuit, a serial data interface circuit, or an inter-board connection circuit to realize data transmission and logical connection between the battery management unit 20 and the wireless communication module Q1.

[0028] Antenna circuit 200 includes: The wireless communication module Q1 is mounted on the circuit board and electrically connected to the wireless connection unit 30. The wireless communication module Q1 has a radio frequency output terminal. The radio frequency output terminal is used to output the processed radio frequency signal to the impedance matching network of the subsequent stage. At the same time, it can also receive external wireless signals received by the antenna body 220, demodulate and decode them, and then feed them back to the wireless connection unit 30.

[0029] Preferably, the wireless communication module Q1 can be a Bluetooth communication module, especially a Bluetooth Low Energy communication module, or it can be extended to a radio frequency module that also has WiFi or other short-range wireless communication capabilities, depending on the actual application scenario.

[0030] An impedance matching network is provided, the input of which is connected to the RF output of the wireless communication module Q1. The impedance matching network includes at least one inductor and at least one capacitor. It is used to perform impedance matching processing on the RF signal output by the wireless communication module Q1 to reduce signal reflection loss and improve the efficiency of RF energy transmission to the antenna body 220.

[0031] The impedance matching network includes at least one inductor and at least one capacitor, preferably configured as an L-type, π-type, or T-type matching structure. For example, a series inductor and a parallel capacitor can be used to form a basic matching unit, or two matching capacitors and a matching inductor L1 can be used to form a π-type network. Through this matching network, the RF link can be tuned according to the impedance characteristics between the wireless communication module Q1, the feed line, and the antenna body 220 to improve the antenna's transmission efficiency and reception sensitivity.

[0032] The filter branch 210, whose input is connected to the output of the impedance matching network, includes a ferrite bead connected in series on the feed line and a bypass capacitor C3 connected in parallel to the communication reference ground G1; it is used to suppress spurious noise and power region coupling interference in the RF transmission path. The ferrite bead connected in series on the feed line and the bypass capacitor C3 connected in parallel to the communication reference ground G1, wherein the ferrite bead connected in series can suppress high-frequency interference components, reducing the possibility of noise from the power loop 50 entering the antenna path along the feed line; the bypass capacitor C3 connected in parallel can discharge some high-frequency spurious noise to the communication reference ground G1.

[0033] Preferably, the filter branch 210 may also be equipped with ESD protection devices, additional bypass capacitor C3 or small-resistance damping elements as needed to further improve the anti-interference performance and electromagnetic compatibility of the antenna circuit 200.

[0034] The antenna body 220 is connected to the output terminal of the filter branch 210. The antenna body 220 is located in the side edge area of ​​the circuit board. This edge arrangement of the antenna body 220 is beneficial to keep away from the power devices, main current path and large-area conductive components inside the battery pack, thereby reducing the obstruction of the wireless signal radiation path and near-field disturbance.

[0035] Preferably, the antenna body 220 can be one of an FPC flexible antenna, a board-edge inverted F antenna, a surface-mounted side antenna, or an embedded printed antenna.

[0036] For battery pack applications, the antenna body 220 located on the side of the circuit board can be closer to the wave-transparent area or non-metallic edge of the housing, thereby improving the transmission efficiency and reception stability of wireless signals.

[0037] The antenna body 220 is surrounded by a clearance isolation zone 230, and an isolation structure S1 is provided between the communication area 240 where the antenna body 220 is located and the power area 250 where the power circuit 50 in the battery pack is located.

[0038] The clearance isolation zone 230 surrounding the antenna body 220 refers to the low-interference space reserved around the antenna body 220 and its adjacent feeder area. Within this clearance isolation zone 230, it is preferable not to place large-area grounding copper foil, high-current traces, power switching devices, metal pressure plates, relays, or other conductive structures that may easily cause near-field radio frequency disturbances. The purpose of setting up the clearance isolation zone 230 is to reduce parasitic coupling and conductor disturbances around the antenna body 220.

[0039] For the isolation structure S1: The isolation structure S1 can be one or more of the following: spatial partitioning between the communication area 240 and the power area 250, reference ground separation, insulating partition, grounding isolation strip, shielding component, or controlled connection structure. Its core function is to reduce the coupling and transmission of electromagnetic interference generated by the power loop 50 during charging, discharging, or current fluctuations to the antenna circuit 200.

[0040] The power circuit 50 is the main current path for energy input and output of the battery pack, and is usually connected to the cell module 10 and external loads and charging equipment. During actual operation, the power circuit 50 carries a large operating current due to charging, discharging, and load changes, and generates significant electromagnetic disturbances with the switching on and off of the power switch. Therefore, it is usually one of the main sources of interference within the battery pack. Although the power circuit 50 is not part of the antenna circuit 200 in this design, its relative arrangement with the communication area 240 where the antenna body 220 is located directly affects the stability of the wireless communication link. Therefore, by setting an isolation structure S1 between the antenna body 220 and the power circuit 50, and setting a clearance isolation area 230 around the antenna body 220, the coupling effect of the power circuit 50 on the wireless signal can be significantly reduced.

[0041] It should be noted that the antenna circuit 200 is a key component in this solution for achieving stable wireless transmission. It is not a single physical antenna, but a complete radio frequency communication branch including the wireless communication module Q1, impedance matching network, filter branch 210, and antenna body 220. By sequentially setting matching and filtering structures between the wireless communication module Q1 and the antenna body 220, the antenna circuit 200 enables the data output from the battery management unit 20 to achieve external wireless transmission with low reflection loss, strong anti-interference capability, and stable transmission and reception after being converted into radio frequency signals. Furthermore, the antenna circuit 200, through edge placement, clearance isolation, and separation of the communication area 240 and power area 250, reduces the impact of the power circuit 50 and conductive components inside the battery pack on the wireless link, thereby improving the overall wireless transmission stability.

[0042] The working principle of this invention is as follows: During operation, the battery cell module 10 provides working power to the entire management circuit. The battery management unit 20 is electrically connected to the battery cell module 10 and collects operating parameters such as voltage, current, temperature, and state of charge of the battery cell module 10. The collected operating parameters are processed by the battery management unit 20 and transmitted to the wireless connection unit 30, which then sends them to the wireless communication module Q1 in the antenna circuit 200. The wireless communication module Q1 converts the received data into a radio frequency signal and outputs it to the impedance matching network from the radio frequency output terminal. After impedance tuning of the radio frequency signal, the impedance matching network sends the signal to the filter branch 210. The filter branch 210 suppresses high-frequency interference through a ferrite bead connected in series on the feed line and discharges spurious noise through a bypass capacitor C3 connected in parallel to the communication reference ground G1. Then, the signal is transmitted to the antenna body 200. The antenna 200 transmits the processed wireless signal outwards or receives wireless signals sent by external terminals and transmits them back to the wireless communication module Q1. Simultaneously, since the antenna body 220 is located on the side edge of the circuit board and is surrounded by a clearance isolation area 230, and the communication area 240 where the antenna body 220 is located is separated from the power area 250 where the power circuit 50 is located within the battery pack through the isolation structure S1, electromagnetic coupling interference generated by the power circuit 50 during charging, discharging, or current fluctuations can be reduced, ensuring stable transmission and reception of wireless signals and achieving stable wireless transmission of battery pack operating data. This solution significantly improves the wireless transmission stability of the battery pack in a complex internal electromagnetic environment through the coordinated design of impedance matching, filtering and noise suppression, and partitioning and isolating the communication area 240 and the power area 250 of the antenna circuit 200.

[0043] In this embodiment, the lithium iron phosphate semi-solid battery pack management circuit also includes a power supply unit 40. The input terminal of the power supply unit 40 is connected to the cell module 10, and the output terminal of the power supply unit 40 is connected to the battery management unit 20 and the wireless communication module Q1, respectively. The power supply unit 40 includes a voltage regulator and filter capacitors disposed on the input side and the output side of the voltage regulator.

[0044] It should be noted that, due to the fluctuations in output voltage during charging, discharging, and load changes of the battery pack, high-frequency ripple or transient interference may occur. Therefore, the power supply unit 40 includes a voltage regulator and filter capacitors located on the input and output sides of the regulator to facilitate smoothing and stabilizing the input voltage. Specifically, the input-side filter capacitor absorbs voltage fluctuations and transient impacts from the cell module 10, while the output-side filter capacitor helps stabilize the regulator's output voltage and reduces the impact of power supply ripple on the battery management unit 20 and the wireless communication module Q1.

[0045] In this embodiment, the battery management unit 20 includes a main control unit 21 and an analog front end 22. In the main control unit 21, the input terminal of the main control unit is connected to the positive and negative terminals of each cell in the cell module 10, and the output terminal of the main control unit 21 is connected to the control terminal of the switching transistor in the power circuit 50.

[0046] The analog front-end 22 is equipped with multiple voltage sampling input terminals and temperature sampling input terminals. The temperature sampling input terminals are connected to the temperature sensor set on the cell module 10. The analog front-end 22 is connected to the main control unit 21 through a serial peripheral interface or integrated circuit bus.

[0047] Specifically, the input terminal of the main control unit in the main control unit 21 is connected to the positive and negative terminals of each cell in the cell module 10, thereby enabling the acquisition of voltage information of a single cell; the output terminal of the main control unit 21 is connected to the control terminal of the switching transistor in the power circuit 50, so that the main control unit 21 can control the switching states such as charging and discharging according to the sampling results and preset control strategies.

[0048] On the other hand, the analog front end 22 is equipped with multiple voltage sampling input terminals and temperature sampling input terminals. The temperature sampling input terminals are connected to temperature sensors installed on the cell module 10 to obtain temperature information at various locations of the cell module 10. The analog front end 22 is then connected to the main control unit 21 through a serial peripheral interface or integrated circuit bus to transmit the collected voltage, temperature and other signals to the main control unit 21 for comprehensive processing.

[0049] In this embodiment, the power circuit 50 further includes a charging switch 51 and a discharging switch 52 connected in series to the positive or negative output terminal of the cell module 10, and a sampling resistor connected in series in the power circuit 50. The two ends of the sampling resistor are connected to the battery management unit 20.

[0050] In this embodiment, it is specifically stated that both the charging switch 51 and the discharging switch 52 are MOSFETs, and the charging switch 51 and the discharging switch 52 are connected in series back to back, with their sources or drains connected together. The sampling resistor is set between the negative output terminal of the cell module 10 and the source of the discharge switch 52, and the resistance value of the sampling resistor is in the range of 0.1 milliohms to 5 milliohms. The power circuit 50 also includes an output filter branch 210 connected in parallel between the positive and negative output terminals of the battery cell module 10. The output filter branch 210 includes at least one electrolytic capacitor and at least one high-frequency ceramic capacitor. The capacitance value of the electrolytic capacitor ranges from 100 microfarads to 1000 microfarads, and the capacitance value of the high-frequency ceramic capacitor ranges from 0.1 microfarads to 10 microfarads.

[0051] By adopting a back-to-back series MOSFET structure, a more reliable bidirectional turn-off capability can be achieved under two different current directions of charging and discharging, thereby avoiding the reverse leakage or abnormal conduction problems caused by the conduction of a single MOSFET body diode, which is beneficial to improving the safety and controllability of battery pack charging and discharging control.

[0052] Furthermore, a sampling resistor is positioned between the negative output terminal of the cell module 10 and the source of the discharge switch 52, ensuring that the charging and discharging current flowing through the battery pack generates a corresponding voltage drop signal across the sampling resistor. The battery management unit 20 can then detect and calculate the current based on this voltage drop signal. Limiting the resistance value of the sampling resistor to 0.1 milliohms to 5 milliohms balances the low power consumption requirements of high-current applications with the necessary sampling accuracy for current detection.

[0053] In this embodiment, the antenna circuit 200 further includes an antenna feed terminal P1 and an ESD protection diode D1; wherein, the antenna feed terminal P1 is disposed between the radio frequency output terminal of the wireless communication module Q1 and the impedance matching network, and is used to introduce the radio frequency signal output by the wireless communication module Q1 into the subsequent radio frequency transmission branch; the ESD protection diode D1 is connected in parallel between the antenna feed terminal P1 and the communication reference ground G1 to form a clear radio frequency connection node.

[0054] It should be noted that when the ESD protection diode D1 is connected in parallel between this node and the communication reference ground G1, it can quickly discharge the surge energy to the communication reference ground G1 when an external electrostatic shock or abnormal high voltage coupling enters the antenna branch, thereby protecting the RF output terminal of the wireless communication module Q1 and the subsequent matching components from damage.

[0055] In this embodiment, the impedance matching network specifically includes a first matching capacitor C1, a matching inductor L1, and a second matching capacitor C2. One end of the first matching capacitor C1 is connected to the antenna feed terminal P1, and the other end of the first matching capacitor C1 is connected to one end of the matching inductor L1. The other end of the matching inductor L1 is connected to one end of the second matching capacitor C2, and the other end of the second matching capacitor C2 is connected to the input terminal of the filter branch 210.

[0056] Specifically, by employing a matching network structure consisting of two matching capacitors and one matching inductor L1, the impedance relationship between the output of the wireless communication module Q1 and the subsequent antenna branch can be adjusted, enabling the RF signal to achieve a better impedance matching state during transmission, thereby reducing reflection loss and improving the transmission efficiency of RF energy. Specifically, the first matching capacitor C1 and the second matching capacitor C2 can be used to adjust the capacitive parameters of the preceding and following stages, respectively, while the matching inductor L1 is used to compensate for the inductive component and, together with the capacitors on both sides, forms a complete matching link.

[0057] In this embodiment, the filter branch 210 includes a high-frequency ferrite bead FB1 connected in series with the feed line and a bypass capacitor C3 connected in parallel with the communication reference ground G1. The high-frequency ferrite bead FB1 is disposed between the output end of the impedance matching network and the antenna body 220. One end of the bypass capacitor C3 is connected to the node between the high-frequency ferrite bead FB1 and the antenna body 220, and the other end of the bypass capacitor C3 is connected to the communication reference ground G1. The communication reference ground G1 and the power reference ground G2 corresponding to the power loop 50 are connected by a single point connection or magnetic coupling.

[0058] It should be noted that by connecting the high-frequency ferrite bead FB1 in series in the antenna feed line, its high impedance to high-frequency spurious interference can be utilized to reduce the possibility of high-frequency noise from the power loop 50 or other conductive components coupling to the antenna body 220 along the feed line. At the same time, by connecting a bypass capacitor C3 in parallel at the node between the high-frequency ferrite bead FB1 and the antenna body 220 and connecting the bypass capacitor C3 to the communication reference ground G1, some high-frequency interference and spurious signals can be discharged, thereby further purifying the radio frequency transmission environment on the feed line.

[0059] Furthermore, by using a single-point connection or magnetic coupling between the communication reference ground G1 and the power reference ground G2, rather than a large-area direct common ground, the ground potential fluctuations and high-frequency ground noise caused by the switching action in the power circuit 50 can be reduced and transmitted to the communication area 240. This achieves relative isolation between the communication area 240 and the power area 250 at the electrical level, which is beneficial to improving the anti-interference capability of the antenna circuit 200 and the electromagnetic compatibility performance of the whole device.

[0060] In this embodiment, the isolation structure S1 is a grounded conductive strip or a metal shielding sheet, which is disposed on the circuit board and located between the feed line side of the antenna body 220 and the power circuit 50. It can form a physical and electromagnetic barrier interface between the two to weaken the influence of the electric field, magnetic field or stray coupling generated by the power circuit 50 during charging, discharging or current fluctuation on the antenna body 220 and the feed line.

[0061] Example 2: The present invention also provides a battery pack management system with stable wireless transmission capability, including a battery pack and a lithium iron phosphate semi-solid battery pack management circuit as described in Embodiment 1.

[0062] This invention not only protects the individual management circuit itself, but also integrates it with the battery pack as a whole to form a complete battery pack management system. By integrating the aforementioned management circuit into the battery pack, the battery pack can perform multiple functions, including operating parameter acquisition, status management, wireless communication, anti-interference processing, and stable data transmission, while fulfilling basic energy storage and energy output functions.

[0063] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lithium iron phosphate semi-solid-state battery pack management circuit, characterized in that, include: Battery cell module; A battery management unit, electrically connected to the battery cell module, is used to collect the operating parameters of the battery cell module; A wireless connection unit is mounted on a circuit board and is electrically connected to the battery management unit; Antenna circuit, the antenna circuit comprising: A wireless communication module is electrically connected to the wireless connection unit, and the wireless communication module is provided with a radio frequency output terminal; An impedance matching network, the input of which is connected to the radio frequency output of the wireless communication module, the impedance matching network including at least one inductor and at least one capacitor. A filtering branch, the input of which is connected to the output of the impedance matching network, includes a ferrite bead connected in series on the feed line and a bypass capacitor connected in parallel to the communication reference ground; the filtering branch also includes a high-frequency ferrite bead connected in series on the feed line and a bypass capacitor connected in parallel to the communication reference ground, the high-frequency ferrite bead being disposed between the output of the impedance matching network and the antenna body, one end of the bypass capacitor being connected to the node between the high-frequency ferrite bead and the antenna body, and the other end of the bypass capacitor being connected to the communication reference ground; the communication reference ground and the power reference ground corresponding to the power loop are connected via a single-point connection or magnetic coupling. The antenna body is connected to the output terminal of the filter branch, and the antenna body is disposed in the side edge area of ​​the circuit board; The antenna body is surrounded by a clearance isolation zone, and an isolation structure is provided between the communication area where the antenna body is located and the power area where the power circuit in the battery pack is located. The isolation structure is a grounded conductive strip or a metal shield, which is set on the circuit board and located between the feed line side of the antenna body and the power circuit. The clearance isolation zone is set around the antenna body and its adjacent feed line area, and no large-area grounded copper foil, high-current traces, power switching devices, metal pressure plates and relays are arranged in the clearance isolation zone.

2. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 1, characterized in that, Also includes: The power supply unit has its input terminal connected to the battery cell module and its output terminal connected to the battery management unit and the wireless communication module, respectively. The power supply unit includes a voltage regulator and filter capacitors disposed on the input and output sides of the voltage regulator.

3. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 2, characterized in that, The battery management unit includes: The main control unit has its input terminal connected to the positive and negative terminals of each cell in the cell module, and its output terminal connected to the control terminal of the switching transistor in the power circuit. The analog front end is provided with multiple voltage sampling input terminals and temperature sampling input terminals. The temperature sampling input terminals are connected to a temperature sensor disposed on the battery cell module. The analog front end is connected to the main control unit through a serial peripheral interface or an integrated circuit bus.

4. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 1, characterized in that, The power circuit includes a charging switch and a discharging switch connected in series with the positive or negative terminal of the cell module output, and a sampling resistor connected in series in the power circuit. The two ends of the sampling resistor are connected to the battery management unit.

5. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 4, characterized in that, Both the charging switch and the discharging switch are MOSFETs, and the charging switch and the discharging switch are connected in series back to back, with their sources or drains connected together. The sampling resistor is positioned between the negative output terminal of the battery cell module and the source of the discharge switch transistor, and the resistance value of the sampling resistor ranges from 0.1 milliohms to 5 milliohms.

6. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 1, characterized in that, The antenna circuit also includes: The antenna feed terminal is located between the radio frequency output terminal of the wireless communication module and the impedance matching network; An ESD protection diode is connected in parallel between the antenna feed terminal and the communication reference ground.

7. The lithium iron phosphate semi-solid-state battery pack management circuit according to claim 6, characterized in that, The impedance matching network includes a first matching capacitor, a matching inductor, and a second matching capacitor. One end of the first matching capacitor is connected to the antenna feed terminal, the other end of the first matching capacitor is connected to one end of the matching inductor, the other end of the matching inductor is connected to one end of the second matching capacitor, and the other end of the second matching capacitor is connected to the input terminal of the filter branch.

8. A battery pack management system with stable wireless transmission capability, characterized in that, It includes a battery pack, and a lithium iron phosphate semi-solid-state battery pack management circuit as described in any one of claims 1 to 7.

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