Equalization circuit and electronic equipment

Abstract

The invention provides an equalization circuit and electronic equipment, the equalization circuit is applied to an energy storage system, the energy storage system comprises at least two battery cells, the equalization circuit comprises an equalization module, at least two first switch modules, at least two second switch modules, at least two battery cell selection modules, a polarity detection module and a main control module; wherein the battery cell selection module corresponding to the target battery cell conducts the first switch module and the second switch module according to the first control signal; after the first switch module and the second switch module are switched on, the polarity detection module judges the polarities of the two ends of the target battery cell according to the voltage difference between the two ends of the target battery cell, connects one end corresponding to the positive electrode of the target battery cell to the first end of the secondary side of the transformer and connects one end corresponding to the negative electrode of the target battery cell to the second end of the secondary side of the transformer according to the judgment result; and a charging loop or a discharging loop for the target cell is formed. Through the mode, the battery cell equalization efficiency and the equalization circuit reliability are improved.

Description

Technical Field

[0001] The present application relates to the field of electronic circuits, and in particular to equalizing circuits and electronic equipment. Background Art

[0002] Typically, multiple batteries are connected in series to meet high-voltage and high-power requirements. The higher the voltage and power requirements, the more strings are required. As the number of battery strings increases, and after the system has been charged and discharged a certain number of times, the battery pack module will cause a voltage "barrel effect" on the entire energy storage system. That is, the battery cell voltage is inconsistent. If one cell's voltage is too high, charging protection will be triggered prematurely, and the system will not be able to charge enough energy. If one cell's voltage is too low, discharge protection will be triggered prematurely, and the system will not be able to provide enough energy for the device.

[0003] Therefore, the batteries need to be balanced. Currently, most BMUs (Battery Management Units) for high-string battery cells use passive balancing. Passive balancing generally only increases the balancing current to hundreds of milliamperes and consumes energy through resistors, but it causes energy to be lost in vain. Most active balancing products on the market lack circuit logic such as switch tube damage detection and battery polarity determination before driving when switching balancing channels, resulting in low reliability and efficiency of the balancing circuit. Summary of the Invention

[0004] To solve the above problems, the present application provides an equalizing circuit and an electronic device, which can improve the reliability and equalizing efficiency of the equalizing circuit.

[0005] A technical solution adopted in the present application is to provide a balancing circuit, which is applied to an energy storage system, the energy storage system includes at least two battery cells, and the balancing circuit includes: a balancing module including a transformer, the first end of the primary side of the transformer is used to couple to the power module, and the second end of the primary side of the transformer is coupled to the first reference ground; at least two first switch modules, the at least two first switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each first switch module is coupled to the first end of its corresponding battery cell, and the second end of each first switch module is coupled to the first end of the secondary side of the transformer; at least two second switch modules, the at least two second switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each second switch module is coupled to the second end of its corresponding battery cell, and the second end of each second switch module is coupled to the second end of the secondary side of the transformer; at least two battery cell selection modules, the at least two battery cell selection modules and the at least two battery cells have a one-to-one correspondence, the first end of each battery cell selection module is coupled to the first end of its corresponding battery cell, and the second end of each battery cell selection module is coupled to the corresponding The second end of the battery cell and the third end of each battery cell selection module are coupled to the power module, and the driving end of each battery cell selection module is coupled to the control end of the first switch module and the second switch module; the polarity detection module, the first input end of the polarity detection module is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module, and the main control module is configured to: in response to the need to perform balancing operation on the target battery cell, send a first control signal to the battery cell selection module corresponding to the target battery cell; wherein the battery cell selection module corresponding to the target battery cell turns on the first switch module and the second switch module according to the first control signal; the polarity detection module is configured to: after the first switch module and the second switch module are turned on, judge the polarity of the two ends of the target battery cell according to the voltage difference between the two ends of the target battery cell, and connect the positive pole corresponding end of the target battery cell to the first end of the secondary side of the transformer according to the judgment result, and connect the negative pole corresponding end of the target battery cell to the second end of the secondary side of the transformer to form a charging circuit or a discharging circuit for the target battery cell.

[0006] In one embodiment, the battery cell selection module includes: a control unit, wherein the first end of the control unit is coupled to the first end of the battery cell corresponding to the battery cell selection module, the second end of the control unit is coupled to the second end of the battery cell corresponding to the battery cell selection module, and the control end of the control unit is coupled to the main control module; a third switch unit, wherein the first end of the third switch unit is coupled to the second end of the battery cell corresponding to the battery cell selection module, and the control end of the third switch unit is coupled to the control unit; a fourth switch unit, wherein the first end of the fourth switch unit is coupled to the power module, the second end of the fourth switch unit is coupled to the control end of the first switch module and the control end of the second switch module, and the control end of the fourth switch unit is coupled to the second end of the third switch unit; wherein, when performing balancing operation on the target battery cell, the control unit turns on the third switch unit and the fourth switch unit according to the first control signal to turn on the first switch module and the second switch module.

[0007] In one embodiment, the control unit includes: a first resistor, wherein the first end of the first resistor is connected to the first end of the battery cell corresponding to the battery cell selection module; a first switch, wherein the first end of the first switch is connected to the second end of the first resistor, and the control end of the first switch is connected to the main control module; and a second resistor, wherein the first end of the second resistor is connected to the second end of the first switch, and the second end of the second resistor is connected to the second end of the battery cell corresponding to the battery cell selection module.

[0008] In one embodiment, the third switch unit includes: a third resistor, a first end of the third resistor is connected to the second end of the first switch; a second switch, a first end of the second switch is connected to the second end of the battery cell corresponding to the battery cell selection module, and a control end of the second switch is connected to the second end of the third resistor; and a fourth resistor, a first end of the fourth resistor is connected to the second end of the second switch.

[0009] In one embodiment, the fourth switch unit includes: a fifth resistor, wherein the first end of the fifth resistor is connected to the power module, and the second end of the fifth resistor is connected to the second end of the fourth resistor; a third switch, wherein the first end of the second switch is connected to the first end of the fifth resistor, and the control end of the third switch is connected to the second end of the fifth resistor; a first diode, wherein the anode of the first diode is connected to the second end of the third switch, and the cathode of the first diode is connected to the control end of the first switch module; a second diode, wherein the anode of the second diode is connected to the second end of the third switch, and the cathode of the second diode is connected to the control end of the second switch module; wherein, when performing balancing operation on the target battery cell, the first switch, the second switch and the third switch are all turned on.

[0010] In one embodiment, the balancing module includes a first driver chip, a fourth switch, a second driver chip, and a fifth switch. The driver end of the first driver chip is coupled to the control end of the fourth switch, the first end of the fourth switch is coupled to the second end of the primary side of the transformer, the second end of the fourth switch is coupled to the first reference ground, the first end of the fifth switch is coupled to the second end of the secondary side of the transformer, and the second end of the fifth switch is coupled to the second reference ground.

[0011] In one embodiment, the balancing circuit further includes: a power switching module coupled to the power module, the second driver chip and the main control module; a driver module coupled to the power switching module, the fifth switch and the second driver chip; the power switching module is configured to: when performing a balancing operation on the target battery cell, in response to discharging the target battery cell, connect the power supply circuit from the power module to the power supply end of the second driver chip and disconnect the power supply circuit from the power module to the power supply end of the driver module; in response to charging the target battery cell, connect the power supply circuit from the power module to the power supply end of the driver module and disconnect the power supply circuit from the power module to the power supply end of the second driver chip;

[0012] Among them, when the target battery cell is balanced and the target battery cell is discharged, the driving end of the second driving chip sends a second control signal to the driving module; the driving module is configured as follows: when the target battery cell is balanced, in response to discharging the target battery cell, the driving module controls the fifth switch to be turned on according to the second control signal; in response to charging the target battery cell, the driving module generates a third control signal and controls the fifth switch to be turned on according to the third control signal.

[0013] In one embodiment, the power switching module includes: a first switching unit, wherein the first end of the first switching unit is coupled to the power module, the second end of the first switching unit is coupled to the second driver chip, and the control end of the first switching unit is coupled to the main control module; a second switching unit, wherein the first end of the second switching unit is coupled to the power module, the second end of the second switching unit is coupled to the driver module, and the control end of the second switching unit is coupled to the first switching unit; wherein, when performing balancing operation on the target battery cell and discharging the target battery cell, the first switching unit turns on the power supply circuit from the power module to the power supply end of the second driver chip, and disconnects the power supply circuit from the power module to the power supply end of the driver module; when performing balancing operation on the target battery cell and charging the target battery cell, the second switching unit turns on the power supply circuit from the power module to the power supply end of the driver module, and disconnects the power supply circuit from the power module to the power supply end of the second driver chip.

[0014] In one embodiment, the first switching unit includes: a sixth switch, a first end of the sixth switch is coupled to the power supply module, and a second end of the sixth switch is connected to the power supply terminal, the bias terminal and the feedback terminal of the second driver chip; a sixth resistor, a first end of the sixth resistor is connected to the control terminal of the sixth switch; a first optocoupler, a first end of the first optocoupler primary side is coupled to the main control module, a second end of the first optocoupler primary side is coupled to the first reference ground, a first end of the first optocoupler secondary side is connected to the second end of the sixth resistor, and a second end of the first optocoupler secondary side is coupled to the second reference ground; a third diode, an anode of the third diode is connected to the second end of the sixth switch; a seventh resistor, a first end of the seventh resistor is connected to the cathode of the third diode, and a second end of the seventh resistor is connected to the second switching unit; a fourth diode, a cathode of the fourth diode is connected to the first end of the first optocoupler secondary side; an eighth resistor, a first end of the eighth resistor is connected to the anode of the fourth diode; and a second end of the eighth resistor is coupled to the second switching unit.

[0015] In one embodiment, the second switching unit includes: a seventh switch, a first end of the seventh switch coupled to the power module, and a second end of the seventh switch coupled to the driving module; a ninth resistor, a first end of the ninth resistor connected to the control end of the seventh switch, and a second end of the ninth resistor connected to the second end of the seventh resistor; an eighth switch, a first end of the eighth switch connected to the second end of the seventh resistor, a second end of the eighth switch coupled to the second reference ground, and a control end of the eighth switch connected to the second end of the eighth resistor; a tenth resistor, a first end of the tenth resistor connected to the first end of the seventh switch, and a second end of the tenth resistor connected to the control end of the eighth switch; a fifth diode, an anode of the fifth diode connected to the second end of the seventh switch; an eleventh resistor, a first end of the eleventh resistor connected to the cathode of the fifth diode, and a second end of the eleventh resistor connected to the first end of the secondary side of the first optocoupler; wherein, when performing a balancing operation on the target battery cell and discharging the target battery cell, the sixth switch and the first optocoupler are turned on, and the seventh switch and the eighth switch are turned off; when performing a balancing operation on the target battery cell and charging the target battery cell, the seventh switch and the eighth switch are turned on, and the sixth switch and the first optocoupler are turned off.

[0016] In one embodiment, the driver module includes: a third driver chip, a power supply terminal of the third driver chip coupled to the power module, and a driving terminal of the third driver chip coupled to the control terminal of a fifth switch; a twelfth resistor, a first terminal of the twelfth resistor coupled to the control terminal of the third driver chip, and a second terminal of the twelfth resistor coupled to the second reference ground; a first driver unit, an input terminal of the first driver unit coupled to the driving terminal of the second driver chip, a control terminal of the first driver unit coupled to the power switching module, and a driving terminal of the first driver unit coupled to the control terminal of the third driver chip; a second driver unit, a first detection terminal of the second driver unit coupled to the first terminal of the fifth switch, a second detection terminal of the second driver unit coupled to the second terminal of the fifth switch, a power supply terminal and a control terminal of the second driver unit coupled to the power switching module, and a driving terminal of the second driver unit coupled to the control terminal of the third driver chip; wherein, when performing a balancing operation on a target battery cell and discharging the target battery cell, the first driver unit controls the third driver chip to turn on the fifth switch according to a second control signal; and when charging the target battery cell, the second driver unit sends a third control signal to the control terminal of the third driver chip to control the third driver chip to turn on the fifth switch.

[0017] In one embodiment, the first driving unit includes: a first voltage regulator tube, wherein the cathode of the first voltage regulator tube is connected to the driving end of the second driving chip; a ninth switch, wherein the first end of the ninth switch is connected to the anode of the first voltage regulator tube, the second end of the ninth switch is connected to the control end of the third driving chip, and the control end of the ninth switch is coupled to the power switching module; and a sixth diode, wherein the cathode of the sixth diode is connected to the cathode of the first voltage regulator tube, and the anode of the sixth diode is connected to the anode of the first voltage regulator tube.

[0018] In one embodiment, the second driving unit includes: a fourth driving chip, a power supply end of the fourth driving chip is coupled to the power switching module, a first detection end of the fourth driving chip is coupled to the first end of the fifth switch, and a second detection end of the fourth driving chip is coupled to the second end of the fifth switch; a second voltage regulator tube, a cathode of the second voltage regulator tube is connected to the driving end of the fourth driving chip; a tenth switch, a first end of the tenth switch is connected to the anode of the second voltage regulator tube, a second end of the tenth switch is connected to the control end of the third driving chip, and the control end of the tenth switch is connected to the power switching module; a seventh diode, a cathode of the seventh diode is connected to the cathode of the second voltage regulator tube, and an anode of the seventh diode is connected to the anode of the second voltage regulator tube.

[0019] In one embodiment, the balancing circuit further includes: a first detection module, wherein a first end of the first detection module is coupled to at least two first switch modules, a second end of the first detection module is coupled to at least two second switch modules, and a detection end of the first detection module is coupled to a main control module; a second detection module, wherein a first end of the second detection module is coupled to at least two first switch modules, a second end of the second detection module is coupled to at least two second switch modules, a third end of the second detection module is coupled to a power supply module, and a detection end of the second detection module is coupled to the main control module.

[0020] In one embodiment, the first detection module includes: an eleventh switch, wherein the first end of the eleventh switch is coupled to the main control module; a third voltage-stabilizing diode, wherein the cathode of the third voltage-stabilizing diode is connected to the first end of the eleventh switch, and the second end of the third voltage-stabilizing diode is coupled to the third reference ground; a thirteenth resistor, wherein the first end of the thirteenth resistor is connected to the first end of the eleventh switch, and the second end of the thirteenth resistor is coupled to the third reference ground; an eighth diode, wherein the cathode of the eighth diode is connected to the second end of the eleventh switch; a fourteenth resistor, wherein the first end of the fourteenth resistor is connected to the anode of the eighth diode, and the second end of the fourteenth resistor is coupled to at least two first switch modules; a ninth diode, wherein the cathode of the ninth diode is connected to the second end of the eleventh switch; and a fifteenth resistor, wherein the first end of the fifteenth resistor is connected to the anode of the ninth diode, and the second end of the fifteenth resistor is coupled to at least two second switch modules.

[0021] In one embodiment, the second detection module includes: a twelfth switch, wherein the first end of the twelfth switch is coupled to the power supply module through a thirteenth resistor; a second optocoupler, wherein the first end of the second optocoupler primary side is connected to the second end of the twelfth switch, the first end of the second optocoupler secondary side is coupled to the main control module, and the second end of the second optocoupler secondary side is coupled to the first reference ground; a sixteenth resistor, wherein the first end of the sixteenth resistor is coupled to the power supply module, and the second end of the sixteenth resistor is connected to the first end of the second optocoupler secondary side; a tenth diode, wherein the anode of the tenth diode is connected to the second end of the second optocoupler primary side, and the cathode of the tenth diode is coupled to at least two first switch modules; and an eleventh diode, wherein the anode of the eleventh diode is connected to the second end of the second optocoupler primary side, and the cathode of the eleventh diode is coupled to at least two second switch modules.

[0022] The present application also provides an electronic device, which includes the above-mentioned equalization circuit.

[0023] A technical solution adopted in the present application is to provide a balancing circuit, which is applied to an energy storage system, the energy storage system includes at least two battery cells, and the balancing circuit includes: a balancing module including a transformer, the first end of the primary side of the transformer is used to couple to the power module, and the second end of the primary side of the transformer is coupled to the first reference ground; at least two first switch modules, the at least two first switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each first switch module is coupled to the first end of its corresponding battery cell, and the second end of each first switch module is coupled to the first end of the secondary side of the transformer; at least two second switch modules, the at least two second switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each second switch module is coupled to the second end of its corresponding battery cell, and the second end of each second switch module is coupled to the second end of the secondary side of the transformer; at least two battery cell selection modules, the at least two battery cell selection modules and the at least two battery cells have a one-to-one correspondence, the first end of each battery cell selection module is coupled to the first end of its corresponding battery cell, and the second end of each battery cell selection module is coupled to the corresponding The second end of the battery cell and the third end of each battery cell selection module are coupled to the power module, and the driving end of each battery cell selection module is coupled to the control end of the first switch module and the second switch module; the polarity detection module, the first input end of the polarity detection module is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module, and the main control module is configured to: in response to the need to perform balancing operation on the target battery cell, send a first control signal to the battery cell selection module corresponding to the target battery cell; wherein the battery cell selection module corresponding to the target battery cell turns on the first switch module and the second switch module according to the first control signal; the polarity detection module is configured to: after the first switch module and the second switch module are turned on, judge the polarity of the two ends of the target battery cell according to the voltage difference between the two ends of the target battery cell, and connect the positive pole corresponding end of the target battery cell to the first end of the secondary side of the transformer according to the judgment result, and connect the negative pole corresponding end of the target battery cell to the second end of the secondary side of the transformer to form a charging circuit or a discharging circuit for the target battery cell. Through the above method, free selection and balancing of multiple battery cells and high conversion efficiency bidirectional balancing between the battery cells and the power module are achieved, thereby improving the battery cell balancing efficiency and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without inventive efforts. Among them:

[0025] Figure 1 is a structural diagram of the first embodiment of the equalization circuit provided by the present application;

[0026] Figure 2 is a structural diagram of a second embodiment of the equalization circuit provided by the present application;

[0027] Figure 3 is a structural diagram of a third embodiment of the equalization circuit provided by the present application;

[0028] Figure 4 is a structural diagram of a fourth embodiment of an equalization circuit provided by the present application;

[0029] Figure 5 is a structural diagram of a fifth embodiment of the equalization circuit provided by the present application;

[0030] Figure 6 is a structural diagram of a sixth embodiment of the equalization circuit provided by the present application;

[0031] Figure 7 It is a structural diagram of an embodiment of an electronic device provided by this application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some, rather than all, structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0033] The terms "first," "second," and the like in this application are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0034] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0035] See Figure 1 , Figure 1This is a structural schematic diagram of the first embodiment of the balancing circuit provided in the present application. The balancing circuit 100 is applied to an energy storage system, which includes at least two battery cells. The balancing circuit 100 includes: a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50 and a main control module 60.

[0036] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0037] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0038] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0039] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0040] Specifically, energy storage systems typically include multiple strings of cells. These strings exhibit unique potential relationships. When two cells (CC1 and CC2) are connected in series, their connection node exhibits dual potential properties: it serves as both the positive terminal of the preceding cell (CC1) and the negative terminal of the subsequent cell (CC2). Therefore, when balancing a target cell within a string, it is necessary to determine whether the node connecting the target cell to the adjacent cell is positive or negative for that cell.

[0041] Specifically, the main control module 60 includes an analog front end (AFE), which can accurately measure information such as the voltage, current, and temperature of each cell in the battery pack. When the AFE detects that a target cell needs to be balanced, it sends a first control signal to the cell selection module 40 corresponding to the target cell, so that the cell selection module 40 starts working, turns on the first switch module 20 and the second switch module 30, and connects the target cell to the two ends of the transformer T. At this time, the polarity detection module 50 determines which end is the positive pole and which end is the negative pole based on the voltage at both ends of the target cell, and connects the positive pole corresponding end of the target cell to the first end of the secondary side of the transformer T (defined as the positive pole), and the negative pole corresponding end of the target cell to the second end of the secondary side of the transformer T (defined as the negative pole), forming a balancing circuit for the target cell.

[0042] Specifically, the main control module 60 also includes an MCU (Microcontroller Unit). At this time, the AFE transmits the voltage data of the target battery cell to the MCU. The MCU determines whether the target battery cell needs to be charged or discharged, and realizes the balancing operation between the power module and the target battery cell through the balancing module 10.

[0043] Specifically, the power module is connected to an external 24V DC power supply (not shown). The power module includes a first transformer unit (not shown), which can specifically include a DCDC chip and an LDO chip. The external 24V DC power supply outputs a first auxiliary voltage source V12V through the DCDC chip. V12V then outputs a second auxiliary voltage source 3V3 through the LDO chip. V12V, 3V3, and 24V are connected to the same reference ground. Among them, the external 24V DC power supply mainly powers the transformer T. V12V is mainly used to power the charging driver chip in the balancing module 10, and 3V3 is mainly used to power the MCU. The power module also includes a second transformer unit (not shown), which can specifically include an isolation transformer T. The 24V DC power supply outputs a third auxiliary voltage source AB12V through the first isolation transformer T. AB12V is mainly used to power the power switching module 70 and the driver module 80. The 24V DC power supply outputs a fourth auxiliary voltage source MPP12V through the second isolation transformer T. MPP12V mainly powers the battery cell selection module 40.

[0044] In the above scheme, the cell selection module 40 controls the conduction state of the switch unit connected to the two ends of the target cell, and the polarity detection module 50 determines the positive and negative polarity of the two ends of the cell, thereby correctly connecting the positive and negative poles of the cell to the positive and negative poles of the secondary side of the transformer T, thereby achieving balancing operation of the target cell. Through the precise control of the cell selection module 40, the first switch module 20, and the second switch module 30, the real-time monitoring and adjustment of the cell state can be achieved; the polarity determination module can accurately determine the positive and negative polarity of the cell, avoiding safety hazards such as short circuit, overheating, and even explosion caused by incorrect polarity connection. The above scheme not only improves the efficiency and accuracy of cell balancing, but also improves the reliability and stability of the circuit.

[0045] See Figure 2 , Figure 2 1 is a schematic diagram of the structure of the second embodiment of the balancing circuit provided in this application. The balancing circuit 100 is applied to an energy storage system including at least two battery cells. The balancing circuit 100 includes: a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50, and a main control module 60.

[0046] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0047] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0048] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0049] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0050] In some embodiments, the cell selection module 40 includes: a control unit 41 , a third switch unit 42 , and a fourth switch unit 43 .

[0051] Among them, the first end of the control unit 41 is coupled to the first end of the battery cell corresponding to the battery cell selection module 40, the second end of the control unit 41 is coupled to the second end of the battery cell corresponding to the battery cell selection module 40, and the control end of the control unit 41 is coupled to the main control module 60; the first end of the third switch unit 42 is coupled to the second end of the battery cell corresponding to the battery cell selection module 40, and the control end of the third switch unit 42 is coupled to the control unit 41; the first end of the fourth switch unit 43 is coupled to the power module, the second end of the fourth switch unit 43 is coupled to the control end of the first switch module 20 and the control end of the second switch module 30, and the control end of the fourth switch unit 43 is coupled to the second end of the third switch unit 42.

[0052] When performing the balancing operation on the target battery cell, the control unit 41 turns on the third switch unit 42 and the fourth switch unit 43 according to the first control signal, so as to turn on the first switch module 20 and the second switch module 30 .

[0053] Specifically, when the AFE detects that the target battery cell needs to be balanced, it sends a first control signal to the control unit 41, so that the third switch unit 42 and the fourth switch unit 43 are turned on, and the voltage signal flows through the control ends of the first switch module 20 and the second switch module 30 through the fourth switch unit 43, so that the first switch module 20 and the second switch module 30 are turned on.

[0054] In some embodiments, the control unit 41 includes a first resistor R1 , a first switch Q1 , and a second resistor R2 .

[0055] Among them, the first end of the first resistor R1 is connected to the first end of the battery cell corresponding to the battery cell selection module 40; the first end of the first switch Q1 is connected to the second end of the first resistor R1, and the control end of the first switch Q1 is connected to the main control module 60; the first end of the second resistor R2 is connected to the second end of the first switch Q1, and the second end of the second resistor R2 is connected to the second end of the battery cell corresponding to the battery cell selection module 40.

[0056] In one embodiment, the third switch unit 42 includes a third resistor R3 , a second switch Q2 , and a fourth resistor R4 .

[0057] Among them, the first end of the third resistor R3 is connected to the second end of the first switch Q1; the first end of the second switch Q2 is connected to the second end of the battery cell corresponding to the battery cell selection module 40, and the control end of the second switch Q2 is connected to the second end of the third resistor R3; the first end of the fourth resistor R4 is connected to the second end of the second switch Q2.

[0058] In one embodiment, the fourth switch unit 43 includes a fifth resistor R5 , a third switch Q3 , a first diode D1 , and a second diode D2 .

[0059] Among them, the first end of the fifth resistor R5 is connected to the power module, and the second end of the fifth resistor R5 is connected to the second end of the fourth resistor R4; the first end of the second switch Q2 is connected to the first end of the fifth resistor R5, and the control end of the third switch Q3 is connected to the second end of the fifth resistor R5; the anode of the first diode D1 is connected to the second end of the third switch Q3, and the cathode of the first diode D1 is connected to the control end of the first switch module 20; the anode of the second diode D2 is connected to the second end of the third switch Q3, and the cathode of the second diode D2 is connected to the control end of the second switch module 30; wherein, when the balancing operation is performed on the target battery cell, the first switch Q1, the second switch Q2 and the third switch Q3 are all turned on.

[0060] Specifically, when the target cell requires balancing, the first switch Q1 is turned on by the first control signal. The target cell forms a loop with the first resistor R1, the first switch Q1, and the second resistor R2. Current then flows through the third resistor R3 to the control terminal of the second switch Q2, turning on the second switch Q2. The voltage signal output by the fourth auxiliary voltage source MPP12V of the power module, after current limiting by the fifth resistor R5 and the fourth resistor R4, reaches the second switch Q2, forming a complete loop with the second terminal of the target cell. At this point, the third switch Q3 is turned on. After the third switch Q3 is turned on, the voltage signal flows through the third switch Q3, through the first diode D1 and the second diode D2, and then through the first diode D1 and the second diode D2, respectively, to the control terminals of the first switch module 20 and the second switch module 30, turning on the first switch module 20 and the second switch module 30.

[0061] The two ends of the target battery cell are connected to the two input ends of the polarity detection module 50 through the first switch module 20 and the second switch module 30 respectively. After polarity determination, the positive pole of the target battery cell is connected to the positive pole of the secondary side of the transformer T, and the negative pole of the target battery cell is connected to the negative pole of the secondary side of the transformer T according to the polarity of the two ends of the target battery cell.

[0062] The first switch Q1, the second switch Q2, and the third switch Q3 may be transistors, whose operating states are controlled by a voltage signal at the base (i.e., the control terminal) of the transistors. In other embodiments, the first switch Q1, the second switch Q2, and the third switch Q3 may also be semiconductor devices such as MOS transistors and IGBTs, which are not listed here.

[0063] In the above scheme, the control unit 41 can quickly respond to the real-time status and needs of the battery cell according to the instructions of the first control signal, accurately control the conduction state of the third switch unit 42 and the fourth switch unit 43, and then make the first switch module 20 and the second switch module 30 conductive, completing the construction of the balancing loop; by utilizing the synergistic effect of multiple switch units, the flexibility of the balancing operation is improved and the reliability of the circuit is improved.

[0064] See Figure 3 , Figure 3 1 is a schematic diagram of the structure of the third embodiment of the balancing circuit provided in this application. The balancing circuit 100 is applied to an energy storage system including at least two battery cells. The balancing circuit 100 includes a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50, and a main control module 60.

[0065] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0066] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0067] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0068] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0069] Figure 3 The equalization circuit 100 shown is Figure 2 The main difference of the balancing circuit 100 shown is that the power switching module 70 and the driving module 80 are added. Therefore, the following mainly describes the power switching module 70 and the driving module 80. For other components in the balancing module 10, please refer to Figure 2 The relevant description of the embodiment shown, e.g. Figure 3 The cell selection module 40 can be found in Figure 2 The description of the cell selection module 40 is omitted here.

[0070] In some embodiments, the balancing module 10 includes a first driver chip U1, a fourth switch Q4, a second driver chip U2, and a fifth switch Q5. The driver terminal GATE1 of the first driver chip U1 is coupled to the control terminal of the fourth switch Q4. The first terminal of the fourth switch Q4 is coupled to the second terminal of the primary side of the transformer T. The second terminal of the fourth switch Q4 is coupled to the first reference ground GND1. The first terminal of the fifth switch Q5 is coupled to the second terminal of the secondary side of the transformer T. The second terminal of the fifth switch Q5 is coupled to the second reference ground GND2.

[0071] The fourth switch Q4 and the fifth switch Q5 may be MOS transistors, and their operating states are controlled by a voltage signal at the gate (i.e., the control terminal) of the MOS transistors. In other embodiments, the fourth switch Q4 and the fifth switch Q5 may also be semiconductor devices such as triodes and IGBTs, which are not listed here.

[0072] Specifically, the first driver chip U1 is a charging chip, the second driver chip U2 is a discharging chip, the fourth switch Q4 is a charging drive switch, and the fifth switch Q5 is a discharging drive switch. The fourth switch Q4 and the fifth switch Q5 are usually connected in parallel with a freewheeling diode (such as Figure 3D11 and D12 are shown. When the AFE detects that the target cell needs to be balanced, the target cell is connected to the secondary side of the transformer T through the first switch module 20, the second switch module 30, and the polarity detection module 50. When the MCU determines that the target cell needs to be charged, the charging enable signal sent by the MCU to the enable terminal EN1 of the first driver chip U1 is high, so that the driver terminal GATE1 of the first driver chip U1 outputs a PWM control signal to control the fourth switch Q4 to turn on. At this time, the voltage of the external 24V DC power supply flows through pins 1 and 4 of the transformer T, the fourth switch Q4, and the freewheeling diode to the first reference ground GND1. At this time, the transformer T stores energy. When the fourth switch Q4 is disconnected, the stored energy will generate a voltage opposite to the same-name terminal of the transformer T due to the inductance of the transformer T. At this time, pin 6 of the transformer T is positive and pin 8 is negative. The voltage signal is transmitted from pin 6 of the transformer T through the positive electrode of the cell, the body diode of the fifth switch Q5, and the freewheeling diode to pin 8 of the transformer T, completing the charging process of the target cell.

[0073] Understandably, when the target cell is charging, the voltage output from the secondary side of transformer T is relatively low. Even with a low-voltage Schottky diode, charging efficiency is significantly impacted when the voltage signal passes through the freewheeling diode and the body diode of the fifth switch Q5. Therefore, when the MCU determines that the target cell needs charging, keeping the fifth switch Q5 on while the fourth switch Q4 is off effectively reduces the voltage drop and improves charging efficiency.

[0074] In some embodiments, the balancing circuit 100 further includes a power switching module 70 and a driving module 80 .

[0075] The power switching module 70 is coupled to the power module, the second driver chip U2 and the main control module 60 ; the driver module 80 is coupled to the power switching module 70 , the fifth switch Q5 and the second driver chip U2 .

[0076] Among them, the power switching module 70 is configured to: when performing a balancing operation on the target battery cell, in response to discharging the target battery cell, connect the power supply circuit from the power supply module to the power supply end of the second driver chip U2, and disconnect the power supply circuit from the power supply module to the power supply end of the driver module 80; in response to charging the target battery cell, connect the power supply circuit from the power supply module to the power supply end of the driver module 80, and disconnect the power supply circuit from the power supply module to the power supply end of the second driver chip U2;

[0077] Among them, when performing balancing operations on the target battery cell and discharging the target battery cell, the driving end of the second driving chip U2 sends a second control signal to the driving module 80; the driving module 80 is configured as follows: when performing balancing operations on the target battery cell, in response to discharging the target battery cell, the driving module 80 controls the fifth switch Q5 to be turned on according to the second control signal; in response to charging the target battery cell, the driving module 80 generates a third control signal and controls the fifth switch Q5 to be turned on according to the third control signal.

[0078] Specifically, when the MCU determines that the target battery cell needs to be charged, the power switching module 70 turns on the power supply circuit from the power module to the power supply end of the driving module 80, so that the driving module 80 sends a third control signal to the fifth switch Q5, thereby turning on the fifth switch Q5 when the fourth switch Q4 is disconnected, thereby reducing the tube voltage drop during charging and improving the charging efficiency.

[0079] Specifically, when the MCU determines that the target battery cell needs to be discharged, the discharge enable signal sent by the MCU to the power switching module 70 is high, and the power switching module 70 turns on the power supply circuit from the third auxiliary voltage source AB12V in the power module to the power supply end of the second driver chip U2, so that the driver end of the second driver chip U2 outputs a PWM control signal (i.e., a second control signal) to the driver module 80, so that the driver module 80 controls the fifth switch Q5 to turn on according to the second control signal. At this time, the energy of the target battery cell flows through the transformer T6 pin, the fifth switch Q5 and the freewheeling diode to the transformer T8 pin, and the transformer T stores energy at this time; when the fifth switch Q5 is disconnected, the stored energy will generate a voltage opposite to the same-name end of the transformer T due to the inductance of the transformer T (flyback switch principle), so at this time, pin 1 of the transformer T is positive and pin 4 is negative, and the target battery cell is discharged through the transformer T.

[0080] Among them, when the target battery cell is discharged, the voltage output by the transformer T will be greater than the voltage output by the external 24V DC power supply. The DC power supply no longer supplies power to the load, but the voltage discharged by the target battery cell through the transformer T supplies power to the load.

[0081] In the above scheme, the power switching module 70 can switch the power module to the power supply circuit of the driving module 80 or the second driving chip U2 when the target battery cell is charged and discharged, thereby changing the conduction logic of the discharge switch (i.e., the fifth switch Q5) when the target battery cell is charged and discharged, so that the discharge switch can also be turned on during charging, thereby reducing the tube voltage drop of the diode and improving the charging efficiency.

[0082] See Figure 4 , Figure 41 is a schematic diagram of the structure of the fourth embodiment of the balancing circuit provided in this application. The balancing circuit 100 is applied to an energy storage system including at least two battery cells. The balancing circuit 100 includes a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50, and a main control module 60.

[0083] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0084] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0085] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0086] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0087] Figure 4 The equalization circuit 100 shown is Figure 3The main difference of the balancing circuit 100 shown is that the components added to the power switching module 70 are described. Therefore, the following mainly describes the components added to the power switching module 70. For other components in the balancing module 10, please refer to Figure 3 The relevant description of the embodiment shown, e.g. Figure 4 The cell selection module 40 can be found in Figure 3 The description of the cell selection module 40 is omitted here.

[0088] In some embodiments, the power switching module 70 includes a first switching unit 71 and a second switching unit 72 .

[0089] Among them, the first end of the first switching unit 71 is coupled to the power module, the second end of the first switching unit 71 is coupled to the second driver chip U2, and the control end of the first switching unit 71 is coupled to the main control module 60; the first end of the second switching unit 72 is coupled to the power module, the second end of the second switching unit 72 is coupled to the driver module 80, and the control end of the second switching unit 72 is coupled to the first switching unit 71.

[0090] Among them, when the target battery cell is balanced and the target battery cell is discharged, the first switching unit 71 turns on the power supply circuit from the power supply module to the power supply end of the second driver chip U2, and disconnects the power supply circuit from the power supply module to the power supply end of the driver module 80; when the target battery cell is balanced and the target battery cell is charged, the second switching unit 72 turns on the power supply circuit from the power supply module to the power supply end of the driver module 80, and disconnects the power supply circuit from the power supply module to the power supply end of the second driver chip U2.

[0091] In some embodiments, the first switching unit 71 includes: a sixth switch Q6 , a sixth resistor R6 , a first optocoupler P1 , a third diode D3 , a seventh resistor R7 , a fourth diode D4 , and an eighth resistor R8 .

[0092] Among them, a first end of the sixth switch Q6 is coupled to the power module, a second end of the sixth switch Q6 is connected to the power end, the bias end, and the feedback end of the second driver chip U2; a first end of the sixth resistor R6 is connected to the control end of the sixth switch Q6; a first end of the primary side of the first optocoupler P1 is coupled to the main control module 60, a second end of the primary side of the first optocoupler P1 is coupled to the first reference ground GND1, a first end of the secondary side of the first optocoupler P1 is connected to the second end of the sixth resistor R6, and a second end of the secondary side of the first optocoupler P1 is coupled to the second reference ground GND2; an anode of the third diode D3 is connected to the second end of the sixth switch Q6; a first end of the seventh resistor R7 is connected to the cathode of the third diode D3, and a second end of the seventh resistor R7 is connected to the second switching unit 72; a cathode of the fourth diode D4 is connected to the first end of the secondary side of the first optocoupler P1; a first end of the eighth resistor R8 is connected to the anode of the fourth diode D4; and a second end of the eighth resistor R8 is coupled to the second switching unit 72.

[0093] In some embodiments, the second switching unit 72 includes a seventh switch Q7 , a ninth resistor R9 , an eighth switch Q8 , a tenth resistor R10 , a fifth diode D5 , and an eleventh resistor R11 .

[0094] A first end of the seventh switch Q7 is coupled to the power module, and a second end of the seventh switch Q7 is coupled to the driver module 80. A first end of the ninth resistor R9 is connected to the control end of the seventh switch Q7, and a second end of the ninth resistor R9 is connected to the second end of the seventh resistor R7. A first end of the eighth switch Q8 is connected to the second end of the seventh resistor R7, a second end of the eighth switch Q8 is coupled to the second reference ground GND2, and a control end of the eighth switch Q8 is connected to the second end of the eighth resistor R8. A first end of the tenth resistor R10 is connected to the first end of the seventh switch Q7, and a second end of the tenth resistor R10 is connected to the control end of the eighth switch Q8. An anode of the fifth diode D5 is connected to the second end of the seventh switch Q7. A first end of the eleventh resistor R11 is connected to the cathode of the fifth diode D5, and a second end of the eleventh resistor R11 is connected to the first end of the secondary side of the first optocoupler P1.

[0095] Among them, when the target battery cell is balanced and discharged, the sixth switch Q6 and the first optocoupler P1 are turned on, and the seventh switch Q7 and the eighth switch Q8 are turned off; when the target battery cell is balanced and charged, the seventh switch Q7 and the eighth switch Q8 are turned on, and the sixth switch Q6 and the first optocoupler P1 are turned off.

[0096] Specifically, when discharging the target battery cell, the charging enable signal issued by the main control module 60 is at a high level, causing the first optocoupler P1 to be turned on. At this time, the control terminal voltage of the eighth switch Q8 is pulled to ground through the eighth resistor R8, the fourth diode D4, and the secondary side of the first optocoupler P1, and the eighth switch Q8 remains in an off state. At this time, the control terminal voltage of the sixth switch Q6 is pulled to ground by the second terminal of the secondary side of the first optocoupler P1 through the sixth resistor R6, causing the sixth switch Q6 to be turned on. The third auxiliary voltage source AB12V is used as the second driver chip U2 power supply AB.12V to supply power to the power supply terminal of the second driver chip U2 through the sixth switch Q6, so that the driver terminal of the second driver chip U2 outputs the second control signal to the driver module 80, and the driver module 80 controls the fifth switch Q5 to be turned on. At the same time, the voltage output by the third auxiliary voltage source AB12V is pulled up through the third diode D3, the seventh resistor R7, and the ninth resistor R9 to increase the control terminal voltage of the seventh switch Q7, so that the seventh switch Q7 remains in an off state, thereby disconnecting the power supply loop from the power module to the power supply terminal of the driver module 80.

[0097] When charging the target battery cell, the charging enable signal issued by the main control module 60 is at a low level, causing the first optocoupler P1 to be disconnected. At this time, the sixth switch Q6 is also disconnected to disconnect the power supply circuit from the power module to the power supply end of the second driver chip U2; at this time, the voltage output by the third auxiliary voltage source AB12V pulls up the voltage of the control end of the eighth switch Q8 through the tenth resistor R10, so that the eighth switch Q8 is turned on, and the control end voltage of the seventh switch Q7 is pulled to the ground through the ninth resistor R9 and the eighth switch Q8, and the seventh switch Q7 is turned on. The third auxiliary voltage source AB12V is used as the fourth driver chip U4 power supply AB.12V through the seventh switch Q7 to power the driver module 80, so that the driver end of the driver module 80 outputs the third control signal to the fifth switch Q5, controlling the fifth switch Q5 to be turned on.

[0098] The sixth switch Q6 and the seventh switch Q7 may be transistors, whose operating states are controlled by the voltage signal at the base (i.e., the control terminal) of the transistors. To improve switching performance and prevent mis-conduction, resistors may be connected between the base and emitter of the sixth and seventh switches. To filter and improve anti-interference capabilities and prevent mis-conduction of the transistors due to high-frequency interference signals, capacitors may be connected between the base and emitter of the sixth and seventh switches. Figure 4 The eighth switch Q8 can be a MOS transistor, such as Figure 4 As shown, a capacitor C3 and a resistor R22 are connected between the gate and source of the eighth switch. In other embodiments, the sixth switch Q6 and the seventh switch Q7 may also be semiconductor devices such as MOS transistors and IGBTs, and the eighth switch Q8 may be semiconductor devices such as triodes and IGBTs, which are not listed here one by one.

[0099] In the above scheme, through the coordinated work of the first switching unit 71 and the second switching unit 72, precise switching of power supply from the power module to the second driver chip U2 and the driver module 80 is achieved. The mutual exclusion between the two power supplies effectively prevents the occurrence of safety hazards such as power supply conflicts and short circuits. It not only achieves precise power management, improves energy efficiency and battery cell balance, but also enhances the safety and reliability of the circuit.

[0100] See Figure 5 , Figure 5 1 is a schematic diagram of the structure of the fifth embodiment of the balancing circuit provided in this application. This balancing circuit 100 is applied to an energy storage system including at least two battery cells. The balancing circuit 100 includes a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50, and a main control module 60.

[0101] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0102] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0103] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0104] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0105] Figure 5 The equalization circuit 100 shown is Figure 4 The main difference of the equalization circuit 100 shown is that the description of the components added to the driving module 80 is added. Therefore, the following mainly describes the components added to the driving module 80. For other components in the equalization module 10, please refer to Figure 4 The relevant description of the embodiment shown, e.g. Figure 5 The power switching module 70 can be found in Figure 4 The description of the power switching module 70 in FIG. 7 is omitted here.

[0106] In some embodiments, the driving module 80 includes: a third driving chip U3 , a twelfth resistor R12 , a first driving unit 81 , and a second driving unit 82 .

[0107] In which, the power supply end of the third driver chip U3 is coupled to the power module, and the driving end of the third driver chip U3 is coupled to the control end of the fifth switch Q5; the first end of the twelfth resistor R12 is coupled to the control end of the third driver chip U3, and the second end of the twelfth resistor R12 is coupled to the second reference ground GND2; the input end of the first driver unit 81 is coupled to the driving end of the second driver chip U2, the control end of the first driver unit 81 is coupled to the power switching module 70, and the driving end of the first driver unit 81 is coupled to the control end of the third driver chip U3; the first detection end of the second driver unit 82 is coupled to the first end of the fifth switch Q5, the second detection end of the second driver unit 82 is coupled to the second end of the fifth switch Q5, the power supply end and the control end of the second driver unit 82 are coupled to the power switching module 70, and the driving end of the second driver unit 82 is coupled to the control end of the third driver chip U3.

[0108] Among them, when performing balancing operation on the target battery cell and discharging the target battery cell, the first driving unit 81 controls the third driving chip U3 to turn on the fifth switch Q5 according to the second control signal; when charging the target battery cell, the second driving unit 82 sends a third control signal to the control end of the third driving chip U3 to control the third driving chip U3 to turn on the fifth switch Q5.

[0109] Specifically, the twelfth resistor R12 is a pull-down resistor to ensure that the third driver chip U3 does not mistakenly turn on the fifth switch Q5; the third driver chip U3 acts as a gate driver, mainly to enhance the driving capability, and the voltage that its control terminal can withstand is limited. When the voltage of the PWM signal input to its control terminal is higher than its tolerance range, it will cause the PWM waveform output by the third driver chip U3 to lag. For example, if the control terminal of the third driver chip U3 can only withstand a maximum voltage of 5V, and a voltage of 10 to 12V is output when the second control signal and the third control signal are high, the PWM waveform output to the control terminal of the fifth switch Q5 after the second control signal and the third control signal pass through the third driver chip U3 will lag, affecting its normal operation. The present application can ensure that the third driver chip U3 drives the fifth switch Q5 to turn on normally within its voltage threshold range through the first drive unit 81 and the second drive unit 82.

[0110] In one embodiment, the first driving unit 81 includes a first voltage regulator tube Z1 , a ninth switch Q9 , and a sixth diode D6 .

[0111] Among them, the cathode of the first voltage-stabilizing tube Z1 is connected to the driving end of the second driver chip U2; the first end of the ninth switch Q9 is connected to the anode of the first voltage-stabilizing tube Z1, the second end of the ninth switch Q9 is connected to the control end of the third driver chip U3, and the control end of the ninth switch Q9 is coupled to the power switching module 70; the cathode of the sixth diode D6 is connected to the cathode of the first voltage-stabilizing tube Z1, and the anode of the sixth diode D6 is connected to the anode of the first voltage-stabilizing tube Z1.

[0112] Specifically, when balancing and discharging the target battery cell, the third auxiliary voltage source AB12V is supplied to the power supply terminal of the second driver chip U2 via the sixth switch Q6 as the power supply AB.12V of the second driver chip U2. This causes the driver terminal of the second driver chip U2 to output a second control signal to the cathode of the first voltage regulator diode Z1. Simultaneously, the power supply AB.12V of the second driver chip U2 supplies power to the control terminal of the ninth switch Q9. The second control signal is a PWM signal. When the second control signal is high, the ninth switch Q9 remains off, and current flows through the first voltage regulator diode Z1 and the body diode of the ninth switch Q9 to the control terminal of the third driver chip U3. When the second control signal is low, the ninth switch Q9 turns on because the voltage difference between the control terminal and the first terminal reaches the threshold voltage. The voltage at the control terminal of the third driver chip U3 is rapidly pulled down by the sixth diode D6, reaching the threshold range of the control terminal of the third driver chip U3.

[0113] In one embodiment, the second driving unit 82 includes: a fourth driving chip U4 , a second voltage regulator diode Z2 , a tenth switch Q10 , and a seventh diode D7 .

[0114] Among them, the power supply end of the fourth driver chip U4 is coupled to the power switching module 70, the first detection end of the fourth driver chip U4 is coupled to the first end of the fifth switch Q5, and the second detection end of the fourth driver chip U4 is coupled to the second end of the fifth switch Q5; the cathode of the second voltage regulator tube Z2 is connected to the driving end of the fourth driver chip U4; the first end of the tenth switch Q10 is connected to the anode of the second voltage regulator tube Z2, the second end of the tenth switch Q10 is connected to the control end of the third driver chip U3, and the control end of the tenth switch Q10 is connected to the power switching module 70; the cathode of the seventh diode D7 is connected to the cathode of the second voltage regulator tube Z2, and the anode of the seventh diode D7 is connected to the anode of the second voltage regulator tube Z2.

[0115] Specifically, when balancing and charging the target battery cells, the third auxiliary voltage source AB12V supplies power to the fourth driver chip U4 via the seventh switch Q7 as the power source AB.12V. At this time, the first and second detection terminals of the fourth driver chip U4 detect the waveform between the first and second terminals of the fifth switch Q5 and output a third control signal to the driver terminal based on the detection result. Simultaneously, the power source AB.12V of the fourth driver chip U4 supplies power to the control terminal of the tenth switch Q10. The third control signal is a PWM signal. When the third control signal is high, the tenth switch Q10 remains off, and current flows through the second voltage regulator diode Z2 and the body diode of the tenth switch Q10 to the control terminal of the third driver chip U3. When the third control signal is low, the tenth switch Q10 turns on because the voltage difference between the control terminal and the first terminal reaches the threshold voltage. The voltage at the control terminal of the third driver chip U3 is rapidly pulled down by the seventh diode D7, reaching the threshold range of the control terminal of the third driver chip U3.

[0116] The ninth switch Q9 and the tenth switch Q10 may be MOS transistors, and their operating states are controlled by a voltage signal at the gate (i.e., the control terminal) of the MOS transistors. In other embodiments, the ninth switch Q9 and the tenth switch Q10 may also be semiconductor devices such as triodes and IGBTs, which are not listed here.

[0117] In the above solution, the voltage of the PWM control signal at the control terminal of the third driver chip U3 is reduced by the first driver unit 81 and the second driver unit 82, so that the third driver chip U3 operates within the voltage threshold range, ensuring that the PWM waveform will not lag after passing through the third driver chip U3, ensuring that the turn-on and turn-off time of the fifth switch Q5 will not lag, and enhancing the synchronous rectification output capability of the circuit.

[0118] See Figure 6 , Figure 6 1 is a schematic diagram of the structure of the sixth embodiment of the balancing circuit provided in this application. This balancing circuit 100 is applied to an energy storage system including at least two battery cells. The balancing circuit 100 includes a balancing module 10, at least two first switch modules 20, at least two second switch modules 30, at least two battery cell selection modules 40, a polarity detection module 50, and a main control module 60.

[0119] The balancing module 10 includes a transformer T, a primary first end of the transformer T is used to couple to the power module, and a primary second end of the transformer T is coupled to the first reference ground GND1; at least two first switch modules 20 correspond one-to-one to at least two battery cells, a first end of each first switch module 20 is coupled to the first end of its corresponding battery cell, and a second end of each first switch module 20 is coupled to the first end of the secondary side of the transformer T; at least two second switch modules 30 correspond one-to-one to at least two battery cells, a first end of each second switch module 30 is coupled to the second end of its corresponding battery cell, and a second end of each second switch module 30 is coupled to the second end of the secondary side of the transformer T. end; there is a one-to-one correspondence between at least two battery cell selection modules 40 and at least two battery cells, the first end of each battery cell selection module 40 is coupled to the first end of its corresponding battery cell, the second end of each battery cell selection module 40 is coupled to the second end of its corresponding battery cell, the third end of each battery cell selection module 40 is coupled to the power module, and the driving end of each battery cell selection module 40 is coupled to the control end of the first switch module 20 and the second switch module 30; the first input end of the polarity detection module 50 is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module 50 is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module 40.

[0120] The main control module is configured to: in response to the need to perform a balancing operation on a target battery cell, send a first control signal to the battery cell selection module 40 corresponding to the target battery cell.

[0121] The cell selection module 40 corresponding to the target cell turns on the first switch module 20 and the second switch module 30 according to the first control signal.

[0122] Among them, the polarity detection module 50 is configured as follows: after the first switch module 20 and the second switch module 30 are turned on, the polarity of the two ends of the target battery cell is judged according to the voltage difference between the two ends of the target battery cell, and according to the judgment result, the positive pole corresponding end of the target battery cell is connected to the first end of the secondary side of the transformer T, and the negative pole corresponding end of the target battery cell is connected to the second end of the secondary side of the transformer T, thereby forming a charging circuit or a discharging circuit for the target battery cell.

[0123] Figure 6 The equalization circuit 100 shown is Figure 4 The main difference of the equalization circuit 100 shown is that the components added to the first detection module 90 and the second detection module 91 are described. Therefore, the following mainly describes the components added to the first detection module 90 and the second detection module 91. For other components in the equalization module 10, please refer to Figure 5 The relevant description of the embodiment shown, e.g. Figure 6 The drive module 80 in Figure 5 The description of the driving module 80 in FIG. 8 is omitted here.

[0124] In some embodiments, the first switch module 20 and the second switch module 30 may include at least one switch tube. In one application scenario, the first switch module 20 and the second switch module 30 each include two switch tubes, such as Figure 6 As shown, when balancing the battery cell CC1, Q22 and Q23 can be used as the first switch module 20, and Q24 and Q25 can be used as the second switch module 30; when balancing the battery cell CC2, Q22 and Q23 can be used as the first switch module 20, and Q20 and Q21 can be used as the second switch module 30.

[0125] The switch tubes in the first switch module 20 and the second switch module 30, such as Q22, Q23, Q24, and Q23, can be MOS tubes, or can be semiconductor devices such as triodes and IGBTs, without limitation. In order to protect the switch tubes, for example, when Q22 and Q23 are MOS tubes, resistors and voltage regulator diodes are usually connected between the gate and source, such as Figure 6 The current limiting resistor R22 and the voltage stabilizing diode Z21 are shown.

[0126] In some embodiments, the equalization circuit 100 further includes: a first detection module 90 and a second detection module 91 .

[0127] Among them, the first end of the first detection module 90 is coupled to at least two first switch modules 20, the second end of the first detection module 90 is coupled to at least two second switch modules 30, and the detection end of the first detection module 90 is coupled to the main control module 60; the first end of the second detection module 91 is coupled to at least two first switch modules 20, the second end of the second detection module 91 is coupled to at least two second switch modules 30, the third end of the second detection module 91 is coupled to the power supply module, and the detection end of the second detection module 91 is coupled to the main control module 60.

[0128] Specifically, the first detection module 90 and the second detection module 91 are connected to the IO (input / output) port of the main control module 60. The main control module 60 can detect the switch tubes in the first switch module 20 and the second switch module 30 by detecting the level changes of the corresponding IO ports.

[0129] In some embodiments, the first detection module 90 includes: an eleventh switch Q11, a third voltage regulator Z3, a thirteenth resistor R13, an eighth diode D8, a fourteenth resistor R14, a ninth diode D9, and a fifteenth resistor R15.

[0130] In particular, a first end of the eleventh switch Q11 is coupled to the main control module 60; a cathode of the third voltage regulator diode Z3 is connected to the first end of the eleventh switch Q11, and a second end of the third voltage regulator diode Z3 is coupled to the third reference ground GND3; a first end of the thirteenth resistor R13 is connected to the first end of the eleventh switch Q11, and a second end of the thirteenth resistor R13 is coupled to the third reference ground GND3; a cathode of the eighth diode D8 is connected to the second end of the eleventh switch Q11; a first end of the fourteenth resistor R14 is connected to the anode of the eighth diode D8, and a second end of the fourteenth resistor R14 is coupled to at least two first switch modules 20; a cathode of the ninth diode D9 is connected to the second end of the eleventh switch Q11; a first end of the fifteenth resistor R15 is connected to the anode of the ninth diode D9, and a second end of the fifteenth resistor R15 is coupled to at least two second switch modules 30.

[0131] In some embodiments, the second detection module 91 includes a twelfth switch Q12 , a second optocoupler P2 , a sixteenth resistor R16 , a tenth diode D10 , and an eleventh diode D11 .

[0132] In which, a first end of the twelfth switch Q12 is coupled to the power module via a thirteenth resistor R13; a first end of the primary side of the second optocoupler P2 is connected to the second end of the twelfth switch Q12, a first end of the secondary side of the second optocoupler P2 is coupled to the main control module 60, and a second end of the secondary side of the second optocoupler P2 is coupled to the first reference ground GND1; a first end of the sixteenth resistor R16 is coupled to the power module, and a second end of the sixteenth resistor R16 is connected to the first end of the secondary side of the second optocoupler P2; an anode of the tenth diode D10 is connected to the second end of the primary side of the second optocoupler P2, and a cathode of the tenth diode D10 is coupled to at least two first switch modules 20; an anode of the eleventh diode D11 is connected to the second end of the primary side of the second optocoupler P2, and a cathode of the eleventh diode D11 is coupled to at least two second switch modules 30.

[0133] In one application scenario, the switch tubes in the first switch module 20 and the second switch module 30 are MOS tubes. It is assumed that the switch tube MOS tube close to the polarity of each battery cell is a high-side MOS tube, and the one at the far end is a low-side MOS tube. Figure 6 As shown, for cell CC1, Q22 and Q24 are high-side MOS transistors, and Q23 and Q25 are low-side MOS transistors. When the high-side MOS transistor is damaged, for example, Q22 is damaged, the eleventh switch Q11 is closed, and the voltage flows from CELL1 through the body diodes of Q22 and Q23, the fourteenth resistor R14, and the eighth diode D8 to the IO port of the main control module 60. At this time, the main control module 60 detects the voltage across the thirteenth resistor R13. If it is detected that the voltage deviates from the preset value (the preset value is determined by the voltage divider value of the fourteenth resistor R14 and the thirteenth resistor R13), the main control module 60 determines that Q22 is faulty.

[0134] When a low-side MOS transistor is damaged, for example, Q23, current cannot flow from CELL1 to Q22 because Q22 is normally closed. The first detection module 90 then fails. The eleventh switch Q11 is opened, and the twelfth switch Q12 is closed. The voltage signal output by the fourth auxiliary voltage source MPP12V of the power module passes through the sixteenth resistor R16, the primary pins 1 and 2 of the second optocoupler P2, the eleventh diode D11, to Q23, and then through the body diode of Q22 to CELL1, forming a complete loop. At this point, the second optocoupler P2 is turned on, and the IO port of the main control module 60 detects a low-level signal, determining that Q23 is faulty.

[0135] In some embodiments, the polarity detection module 50 includes: a polarity determination unit 51 , a thirteenth switch Q13 , a fourteenth switch Q14 , a fifteenth switch Q15 , and a sixteenth switch Q16 .

[0136] The first input terminal of the polarity determination unit 51 is coupled to the first terminals of at least two battery cells, and the second input terminal of the polarity determination unit 51 is coupled to the second terminals of at least two battery cells. The first terminal of the thirteenth switch Q13 is coupled to the first terminals of at least two battery cells, and the second terminal of the thirteenth switch Q13 is coupled to the second terminal of the secondary side of the transformer T. The control terminal of the thirteenth switch Q13 is coupled to the first output terminal of the polarity determination unit 51. The first terminal of the fourteenth switch Q14 is coupled to the second terminals of at least two battery cells, and the second terminal of the fourteenth switch Q14 is coupled to the second terminal of the secondary side of the transformer T. The control end of the fourteenth switch Q14 is coupled to the second output end of the polarity determination unit 51; the first end of the fifteenth switch Q15 is coupled to the first ends of at least two battery cells, the second end of the fifteenth switch Q15 is coupled to the first end of the secondary side of the transformer T, and the control end of the fifteenth switch Q15 is coupled to the second output end of the polarity determination unit 51; the first end of the sixteenth switch Q16 is coupled to the second ends of at least two battery cells, the second end of the sixteenth switch Q16 is coupled to the first end of the secondary side of the transformer T, and the control end of the sixteenth switch Q16 is coupled to the first output end of the polarity determination unit 51.

[0137] In one application scenario, the battery cell CC1 is balanced, the first switch module 20 and the second switch module 30 are turned on, and after judgment by the polarity detection module 50, the second output end of the polarity detection module 50 outputs a drive signal to control the fourteenth switch Q14 and the fifteenth switch Q15 to be turned on. At this time, the thirteenth switch Q13 and the sixteenth switch Q16 remain in the off state, and the positive electrode (CELL1) of the battery cell CC1 is connected to the 6th pin of the secondary side of the transformer T (the positive pole of the transformer T) through the fifteenth switch Q15, and the negative electrode (CELL0) of the battery cell CC1 is connected to the 8th pin of the secondary side of the transformer T (the negative pole of the transformer T) through the fourteenth switch Q14.

[0138] A technical solution adopted in the present application is to provide a balancing circuit, which is applied to an energy storage system, the energy storage system includes at least two battery cells, and the balancing circuit includes: a balancing module including a transformer, the first end of the primary side of the transformer is used to couple to the power module, and the second end of the primary side of the transformer is coupled to the first reference ground; at least two first switch modules, the at least two first switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each first switch module is coupled to the first end of its corresponding battery cell, and the second end of each first switch module is coupled to the first end of the secondary side of the transformer; at least two second switch modules, the at least two second switch modules and the at least two battery cells have a one-to-one correspondence, the first end of each second switch module is coupled to the second end of its corresponding battery cell, and the second end of each second switch module is coupled to the second end of the secondary side of the transformer; at least two battery cell selection modules, the at least two battery cell selection modules and the at least two battery cells have a one-to-one correspondence, the first end of each battery cell selection module is coupled to the first end of its corresponding battery cell, and the second end of each battery cell selection module is coupled to the corresponding The second end of the battery cell and the third end of each battery cell selection module are coupled to the power module, and the driving end of each battery cell selection module is coupled to the control end of the first switch module and the second switch module; the polarity detection module, the first input end of the polarity detection module is coupled to the first end of at least two battery cells, and the second input end of the polarity detection module is coupled to the second end of at least two battery cells; the main control module is coupled to the control end of the battery cell selection module, and the main control module is configured to: in response to the need to perform balancing operation on the target battery cell, send a first control signal to the battery cell selection module corresponding to the target battery cell; wherein the battery cell selection module corresponding to the target battery cell turns on the first switch module and the second switch module according to the first control signal; the polarity detection module is configured to: after the first switch module and the second switch module are turned on, judge the polarity of the two ends of the target battery cell according to the voltage difference between the two ends of the target battery cell, and connect the positive pole corresponding end of the target battery cell to the first end of the secondary side of the transformer according to the judgment result, and connect the negative pole corresponding end of the target battery cell to the second end of the secondary side of the transformer to form a charging circuit or a discharging circuit for the target battery cell. Through the above method, free selection and balancing of multiple battery cells and high conversion efficiency bidirectional balancing between the battery cells and the power module are achieved, thereby improving the battery cell balancing efficiency and reliability.

[0139] See Figure 7 , Figure 7 1 is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. The electronic device 1000 includes an equalization circuit 100, which is the same as the equalization circuit 100 described above and will not be described in detail here.

[0140] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules or units is merely a logical functional division. In actual implementation, other division methods may be used, such as combining or integrating multiple units or components into another system, or ignoring or not implementing certain features.

[0141] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of this embodiment.

[0142] In addition, each functional unit in each embodiment of the present application may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The above-mentioned integrated units may be implemented in the form of hardware or software functional units.

[0143] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An equalization circuit, characterized in that: The balancing circuit is applied to an energy storage system, wherein the energy storage system includes at least two battery cells, and the balancing circuit includes: The balancing module includes a transformer, wherein a primary first end of the transformer is coupled to the power module, and a primary second end of the transformer is coupled to a first reference ground; At least two first switch units, wherein the at least two first switch units correspond to the at least two battery cells in a one-to-one manner, a first end of each first switch unit is coupled to the first end of its corresponding battery cell, and a second end of each first switch unit is coupled to the first end of the secondary side of the transformer; at least two second switch units, wherein the at least two second switch units correspond to the at least two battery cells in a one-to-one manner, a first end of each second switch unit is coupled to the second end of the corresponding battery cell, and a second end of each second switch unit is coupled to the second end of the secondary side of the transformer; At least two battery cell selection modules, wherein the at least two battery cell selection modules correspond to the at least two battery cells on a one-to-one basis, a first end of each battery cell selection module is coupled to the first end of its corresponding battery cell, a second end of each battery cell selection module is coupled to the second end of its corresponding battery cell, a third end of each battery cell selection module is coupled to the power module, and a driving end of each battery cell selection module is coupled to the control ends of the first switch unit and the second switch unit; a polarity detection module, wherein a first input terminal of the polarity detection module is coupled to the first terminals of the at least two battery cells, a second input terminal of the polarity detection module is coupled to the second terminals of the at least two battery cells, a first output terminal of the polarity detection module is coupled to the first terminal of the secondary side of the transformer, and a second output terminal of the polarity detection module is coupled to the second terminal of the secondary side of the transformer; a main control module coupled to the control terminal of the cell selection module, wherein the main control module is configured to: in response to a need to perform a balancing operation on a target cell, send a first control signal to the cell selection module corresponding to the target cell; The cell selection module corresponding to the target cell turns on the first switch unit and the second switch unit according to the first control signal; The polarity detection module is configured to: after the first switching unit and the second switching unit are turned on, judge the polarity of the two ends of the target battery cell according to the voltage difference between the two ends of the target battery cell, and connect the positive pole corresponding end of the target battery cell to the first end of the secondary side of the transformer, and connect the negative pole corresponding end of the target battery cell to the second end of the secondary side of the transformer according to the judgment result, so as to form a charging circuit or a discharging circuit for the target battery cell.

2. The equalizing circuit according to claim 1, wherein: The cell selection module includes: a control unit, wherein a first end of the control unit is coupled to a first end of a battery cell corresponding to the battery cell selection module, a second end of the control unit is coupled to a second end of a battery cell corresponding to the battery cell selection module, and a control end of the control unit is coupled to the main control module; a third switch unit, wherein a first end of the third switch unit is coupled to the second end of the battery cell corresponding to the battery cell selection module, and a control end of the third switch unit is coupled to the control unit; a fourth switch unit, wherein a first end of the fourth switch unit is coupled to the power module, a second end of the fourth switch unit is coupled to a control end of the first switch unit and a control end of the second switch unit, and the control end of the fourth switch unit is coupled to the second end of the third switch unit; When performing the balancing operation on the target battery cell, the control unit turns on the third switch unit and the fourth switch unit according to the first control signal, so that the first switch unit and the second switch unit are turned on.

3. The equalizing circuit according to claim 2, wherein: The control unit comprises: a first resistor, wherein a first end of the first resistor is connected to a first end of a battery cell corresponding to the battery cell selection module; a first switch, wherein a first end of the first switch is connected to the second end of the first resistor, and a control end of the first switch is connected to the main control module; a second resistor, wherein a first end of the second resistor is connected to the second end of the first switch, and a second end of the second resistor is connected to the second end of the battery cell corresponding to the battery cell selection module; The third switch unit includes: a third resistor, a first end of the third resistor being connected to the second end of the first switch; a second switch, wherein a first end of the second switch is connected to the second end of the battery cell corresponding to the battery cell selection module, and a control end of the second switch is connected to the second end of the third resistor; a fourth resistor, a first end of the fourth resistor being connected to the second end of the second switch; The fourth switch unit includes: a fifth resistor, wherein a first end of the fifth resistor is connected to the power module, and a second end of the fifth resistor is connected to the second end of the fourth resistor; a third switch, wherein a first end of the second switch is connected to the first end of the fifth resistor, and a control end of the third switch is connected to the second end of the fifth resistor; a first diode, wherein an anode of the first diode is connected to the second end of the third switch, and a cathode of the first diode is connected to the control end of the first switch unit; a second diode, wherein an anode of the second diode is connected to the second end of the third switch, and a cathode of the second diode is connected to the control end of the second switch unit; Wherein, when the balancing operation is performed on the target battery cell, the first switch, the second switch and the third switch are all turned on.

4. The equalizing circuit according to claim 1, wherein: The balancing module includes a first driver chip, a fourth switch, a second driver chip, and a fifth switch, wherein the driving end of the first driver chip is coupled to the control end of the fourth switch, the first end of the fourth switch is coupled to the second end of the primary side of the transformer, the second end of the fourth switch is coupled to the first reference ground, the first end of the fifth switch is coupled to the second end of the secondary side of the transformer, and the second end of the fifth switch is coupled to the second reference ground; The balancing circuit further includes: a power switching module, coupled to the power module, the second driver chip and the main control module; a driving module coupled to the power switching module, the fifth switch and the second driving chip; The power switching module is configured to: when performing a balancing operation on the target battery cell, in response to discharging the target battery cell, connect the power supply circuit from the power supply module to the power supply terminal of the second driver chip and disconnect the power supply circuit from the power supply module to the power supply terminal of the driver module; in response to charging the target battery cell, connect the power supply circuit from the power supply module to the power supply terminal of the driver module and disconnect the power supply circuit from the power supply module to the power supply terminal of the second driver chip; Wherein, when performing a balancing operation on the target battery cell and discharging the target battery cell, the driving end of the second driving chip sends a second control signal to the driving module; The driving module is configured to: when performing a balancing operation on the target battery cell, in response to discharging the target battery cell, the driving module controls the fifth switch to be turned on according to the second control signal; in response to charging the target battery cell, the driving module generates a third control signal and controls the fifth switch to be turned on according to the third control signal.

5. The equalizing circuit according to claim 4, characterized in that: The power switching module includes: a first switching unit, wherein a first end of the first switching unit is coupled to the power module, a second end of the first switching unit is coupled to the second driving chip, and a control end of the first switching unit is coupled to the main control module; a second switching unit, wherein a first end of the second switching unit is coupled to the power module, a second end of the second switching unit is coupled to the driving module, and a control end of the second switching unit is coupled to the first switching unit; Among them, when the target battery cell is balanced and the target battery cell is discharged, the first switching unit turns on the power supply circuit from the power module to the power supply end of the second driver chip, and disconnects the power supply circuit from the power module to the power supply end of the driver module; when the target battery cell is balanced and the target battery cell is charged, the second switching unit turns on the power supply circuit from the power module to the power supply end of the driver module, and disconnects the power supply circuit from the power module to the power supply end of the second driver chip.

6. The equalizing circuit according to claim 5, characterized in that: The first switching unit includes: a sixth switch, wherein a first end of the sixth switch is coupled to the power module, and a second end of the sixth switch is connected to a power terminal, a bias terminal, and a feedback terminal of the second driver chip; a sixth resistor, a first end of the sixth resistor being connected to the control end of the sixth switch; a first optocoupler, wherein a first end of a primary side of the first optocoupler is coupled to the main control module, a second end of the primary side of the first optocoupler is coupled to the first reference ground, a first end of a secondary side of the first optocoupler is connected to the second end of the sixth resistor, and a second end of the secondary side of the first optocoupler is coupled to the second reference ground; a third diode, wherein an anode of the third diode is connected to the second end of the sixth switch; a seventh resistor, wherein a first end of the seventh resistor is connected to the cathode of the third diode, and a second end of the seventh resistor is connected to the second switching unit; a fourth diode, wherein a cathode of the fourth diode is connected to the first end of the secondary side of the first optocoupler; an eighth resistor, wherein a first end of the eighth resistor is connected to the anode of the fourth diode; and a second end of the eighth resistor is coupled to the second switching unit.

7. The equalizing circuit according to claim 6, wherein: The second switching unit includes: a seventh switch, wherein a first end of the seventh switch is coupled to the power module, and a second end of the seventh switch is coupled to the driving module; a ninth resistor, wherein a first end of the ninth resistor is connected to the control end of the seventh switch, and a second end of the ninth resistor is connected to the second end of the seventh resistor; an eighth switch, wherein a first end of the eighth switch is connected to the second end of the seventh resistor, a second end of the eighth switch is coupled to the second reference ground, and a control end of the eighth switch is connected to the second end of the eighth resistor; a tenth resistor, wherein a first end of the tenth resistor is connected to the first end of the seventh switch, and a second end of the tenth resistor is connected to the control end of the eighth switch; a fifth diode, an anode of the fifth diode connected to the second end of the seventh switch; an eleventh resistor, wherein a first end of the eleventh resistor is connected to the cathode of the fifth diode, and a second end of the eleventh resistor is connected to the first end of the secondary side of the first optocoupler; Among them, when the target battery cell is balanced and the target battery cell is discharged, the sixth switch and the first optocoupler are turned on, and the seventh switch and the eighth switch are turned off; when the target battery cell is balanced and the target battery cell is charged, the seventh switch and the eighth switch are turned on, and the sixth switch and the first optocoupler are turned off.

8. The equalizing circuit according to claim 4, wherein: The driving module includes: a third driver chip, wherein a power supply terminal of the third driver chip is coupled to the power module, and a driving terminal of the third driver chip is coupled to the control terminal of the fifth switch; a twelfth resistor, a first end of the twelfth resistor being coupled to the control end of the third driving chip, and a second end of the twelfth resistor being coupled to the second reference ground; a first driving unit, wherein an input terminal of the first driving unit is coupled to a driving terminal of the second driving chip, a control terminal of the first driving unit is coupled to the power switching module, and a driving terminal of the first driving unit is coupled to a control terminal of the third driving chip; a second driving unit, wherein a first detection terminal of the second driving unit is coupled to the first terminal of the fifth switch, a second detection terminal of the second driving unit is coupled to the second terminal of the fifth switch, a power supply terminal and a control terminal of the second driving unit are coupled to the power switching module, and a driving terminal of the second driving unit is coupled to the control terminal of the third driving chip; When performing a balancing operation on the target battery cell and discharging the target battery cell, the first driving unit controls the third driving chip to turn on the fifth switch according to the second control signal; when charging the target battery cell, the second driving unit sends the third control signal to the control end of the third driving chip to control the third driving chip to turn on the fifth switch.

9. The equalizing circuit according to claim 8, characterized in that: The first driving unit includes: a first voltage-stabilizing tube, wherein a cathode of the first voltage-stabilizing tube is connected to a driving end of the second driving chip; a ninth switch, wherein a first end of the ninth switch is connected to the anode of the first voltage regulator tube, a second end of the ninth switch is connected to the control end of the third driver chip, and the control end of the ninth switch is coupled to the power switching module; a sixth diode, wherein a cathode of the sixth diode is connected to the cathode of the first voltage-stabilizing diode, and an anode of the sixth diode is connected to the anode of the first voltage-stabilizing diode; The second driving unit includes: a fourth driver chip, wherein a power supply terminal of the fourth driver chip is coupled to the power switching module, a first detection terminal of the fourth driver chip is coupled to the first terminal of the fifth switch, and a second detection terminal of the fourth driver chip is coupled to the second terminal of the fifth switch; a second voltage-stabilizing tube, wherein a cathode of the second voltage-stabilizing tube is connected to a driving end of the fourth driving chip; a tenth switch, wherein a first end of the tenth switch is connected to the anode of the second voltage regulator tube, a second end of the tenth switch is connected to the control end of the third driver chip, and the control end of the tenth switch is connected to the power switching module; A seventh diode, wherein the cathode of the seventh diode is connected to the cathode of the second voltage-stabilizing diode, and the anode of the seventh diode is connected to the anode of the second voltage-stabilizing diode.

10. The equalizing circuit according to claim 1, wherein: The balancing circuit further includes: a first detection module, wherein a first end of the first detection module is coupled to the at least two first switch units, a second end of the first detection module is coupled to the at least two second switch units, and a detection end of the first detection module is coupled to the main control module; A second detection module, wherein the first end of the second detection module is coupled to the at least two first switch units, the second end of the second detection module is coupled to the at least two second switch units, the third end of the second detection module is coupled to the power supply module, and the detection end of the second detection module is coupled to the main control module.

11. The equalizing circuit according to claim 10, wherein: The first detection module includes: an eleventh switch, a first end of the eleventh switch being coupled to the main control module; a third voltage-stabilizing diode, wherein a cathode of the third voltage-stabilizing diode is connected to the first end of the eleventh switch, and a second end of the third voltage-stabilizing diode is coupled to a third reference ground; a thirteenth resistor, wherein a first end of the thirteenth resistor is connected to the first end of the eleventh switch, and a second end of the thirteenth resistor is coupled to the third reference ground; an eighth diode, wherein a cathode of the eighth diode is connected to the second end of the eleventh switch; a fourteenth resistor, a first end of the fourteenth resistor being connected to the anode of the eighth diode, and a second end of the fourteenth resistor being coupled to the at least two first switch units; a ninth diode, wherein a cathode of the ninth diode is connected to the second end of the eleventh switch; A fifteenth resistor, wherein a first end of the fifteenth resistor is connected to the anode of the ninth diode, and a second end of the fifteenth resistor is coupled to the at least two second switch units.

12. The equalizing circuit according to claim 10, wherein: The second detection module includes: a twelfth switch, a first end of the twelfth switch being coupled to the power module via a thirteenth resistor; a second optocoupler, wherein a first end of a primary side of the second optocoupler is connected to the second end of the twelfth switch, a first end of a secondary side of the second optocoupler is coupled to the main control module, and a second end of a secondary side of the second optocoupler is coupled to the first reference ground; a sixteenth resistor, a first end of the sixteenth resistor being coupled to the power module, and a second end of the sixteenth resistor being connected to the first end of the secondary side of the second optocoupler; a tenth diode, wherein an anode of the tenth diode is connected to the second primary end of the second optocoupler, and a cathode of the tenth diode is coupled to the at least two first switch units; an eleventh diode, wherein an anode of the eleventh diode is connected to the second primary end of the second optocoupler, and a cathode of the eleventh diode is coupled to the at least two second switch units.

13. An electronic device, characterized in that: The electronic device comprises the equalizing circuit according to any one of claims 1 to 12.

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