Battery pack charge and discharge equalization equipment

Abstract

The utility model discloses a battery pack charge and discharge equalization device, which is electrically connected with a battery pack comprising a plurality of battery cells and comprises a shell and a control circuit board arranged in the shell, the control circuit board comprises a plurality of equalization modules and a controller, and the equalization modules are in one-to-one correspondence with the battery cells. Each equalization module comprises a battery cell information sampling circuit for acquiring battery cell information of the corresponding battery cell, a charging circuit for controlling the corresponding battery cell to charge and a discharging circuit for controlling the corresponding battery cell to discharge; wherein the battery cell information of the battery cell comprises voltage information, current information and temperature information of the battery cell; the controller is connected with the equalization module; a plurality of equalization interface groups are arranged on the shell, the equalization interface groups are in one-to-one correspondence with the equalization modules and are connected with the equalization modules, and the battery pack charge-discharge equalization equipment is connected with the battery pack through the equalization interface groups; and the equalization interface group comprises a ground connection port, and a battery cell positive electrode connection port and a battery cell negative electrode connection port which are respectively connected with the positive electrode and the negative electrode of the battery cell through data lines.

Description

Technical Field

[0001] The utility model relates to the technical field of battery charge and discharge management, in particular to a battery pack charge and discharge balancing device. Background Art

[0002] Due to manufacturing tolerances, such as variations in electrode thickness and overall assembly connectivity, the characteristics of the cells vary slightly, and due to limited manufacturing precision, the initial capacity and impedance of the cells in the same batch also vary. These parameter deviations are Gaussian (normal) distributed. Different cell capacities and impedances mean that in a series connection, one of the cells or multiple cell blocks (multiple cells in parallel) will reach the end of charge or discharge first. For safety reasons, the charge and discharge of the battery pack cannot exceed the voltage limit of the cells that reach the end of charge or discharge first, resulting in the capacity of the other cells not being fully utilized. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a battery pack charge and discharge equalization device, so as to perform equalization operation control on each battery cell of the battery pack individually so that each battery cell can reach the equalization target voltage and improve the utilization rate of the capacity of the battery cell.

[0004] In order to solve the above technical problems, the purpose of the utility model is achieved through the following technical solutions: providing a battery pack charge and discharge balancing device, which is electrically connected to the battery pack, the battery pack includes a plurality of battery cells, the battery pack charge and discharge balancing device includes a shell and a control circuit board arranged in the shell, the control circuit board includes a plurality of balancing modules and a controller, the balancing modules correspond to the battery cells one by one, each of the balancing modules includes a battery cell information sampling circuit for collecting and obtaining the battery cell information of the corresponding battery cell, a charging circuit for controlling the charging of the corresponding battery cell, and a discharge circuit for controlling the discharge of the corresponding battery cell. circuit; wherein the cell information of the cell includes voltage information, current information and temperature information of the cell; the controller is connected to the balancing module; a plurality of balancing interface groups are provided on the shell, the balancing interface groups correspond to and are connected to the balancing modules one by one, and the battery pack charge and discharge balancing device is connected to the battery pack through the balancing interface group; the balancing interface group includes a cell positive electrode connection port, a cell negative electrode connection port and a ground connection port, the cell positive electrode connection port and the cell negative electrode connection port are respectively connected to the positive electrode and negative electrode of the corresponding cell through data lines, and the ground connection port is connected to the ground terminal through the data line.

[0005] The beneficial technical effect of the utility model is that the battery pack charge and discharge balancing device of the utility model is electrically connected to the battery pack, and a plurality of balancing modules corresponding to a plurality of battery cells of the battery pack are arranged on the control circuit board of the battery charge and discharge balancing device to control the balancing operation of each battery cell individually so that each battery cell can reach the balanced target voltage, thereby improving the utilization rate of the capacity of the battery cell, and each battery cell can be independently balanced simultaneously, which can improve the consistency of the battery cell voltage, so that the battery pack as a whole can reach the balance faster, and the efficiency and effect of the balance can be improved, and the number and position of the battery cells for a single balancing operation are not limited, and the flexibility is strong, and the balancing module corresponds to the battery cell one by one for balancing, which can effectively improve the safety of the balancing, and the balancing modules and the battery cells will not interfere with each other, which is safer and more reliable; a controller connected to the balancing module is arranged on the control circuit board, so that A controller is used to control the operation of each balancing module, and the balancing module includes a cell information sampling circuit, a charging circuit and a discharging circuit. Each cell has an independent cell information sampling circuit, a charging circuit and a discharging circuit. The cell information sampling circuit is used in conjunction with the controller to realize the balancing trigger judgment of the corresponding cell. The charging circuit and the discharging circuit are combined to balance the cell by charging or discharging according to the sampling situation, so that the balancing operation is more accurate and reliable, and the heating problem and the long balancing time and low efficiency caused by only discharging balancing operation can be prevented. At the same time, overvoltage, undervoltage, low temperature and overheating detection can be performed based on the cell information of the collected cell to realize overvoltage, undervoltage, low temperature and overheating protection of the cell, and the charging circuit and the discharging circuit of the balancing module connected to the corresponding cell can be shut down according to the detection result, and the alarm information can be uploaded. In addition, by providing a shell and providing a balancing interface group on the shell, each battery cell of the battery pack is inserted into the corresponding balancing interface group through the corresponding data line to be connected with the balancing module of the battery pack charge and discharge balancing device, so that charge and discharge balancing can be performed according to the cell information sampling of the battery cell through the data line connection. The battery pack charge and discharge balancing device is independently provided separately from the battery pack. The battery pack charge and discharge balancing device does not need to disassemble the battery pack for maintenance, which can reduce maintenance intensity, save maintenance cost and maintenance work intensity, save maintenance time, improve maintenance efficiency, reduce production stoppage losses, and improve safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0007] Figure 1 A schematic diagram of the structure of a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0008] Figure 2 A front view of a battery pack charge and discharge equalization device provided by an embodiment of the utility model;

[0009] Figure 3 A top view of a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0010] Figure 4 A rear view of a battery pack charge and discharge equalization device provided by an embodiment of the utility model;

[0011] Figure 5 A schematic diagram of the structure of the connection between the battery pack charge and discharge equalization device provided by the embodiment of the utility model and the battery pack;

[0012] Figure 6 A schematic diagram of a framework for connecting a battery pack charge and discharge equalization device provided by an embodiment of the utility model to a battery pack;

[0013] Figure 7 A schematic diagram of the assembly of the battery pack charge and discharge equalization device provided by the embodiment of the utility model when it is used in a specific application;

[0014] Figure 8 A circuit diagram of a controller of a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0015] Fig. 9 A circuit diagram of a cell information sampling circuit of a battery pack charge and discharge balancing device provided in an embodiment of the utility model;

[0016] Fig.10 A circuit diagram of a communication circuit of a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0017] Fig.11 A circuit diagram of a DC / DC buck module of a battery pack charge and discharge balancing device provided by an embodiment of the utility model;

[0018] Fig.12 A circuit diagram of a buck-boost charge-discharge controller for a battery pack charge-discharge balancing device provided in an embodiment of the utility model;

[0019] Fig.13 A circuit diagram of a charging switch control unit of a battery pack charging and discharging equalization device provided by an embodiment of the utility model;

[0020] Fig.14 A circuit diagram of a discharge circuit of a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0021] Fig.15 A circuit diagram of a chip enabling circuit of a battery pack charge and discharge balancing device provided by an embodiment of the utility model;

[0022] Fig.16 A circuit diagram of a current dynamic control circuit of a battery pack charge and discharge equalization device provided by an embodiment of the utility model;

[0023] Fig.17 A circuit diagram of a charge and discharge direction control circuit of a battery pack charge and discharge equalization device provided by an embodiment of the utility model;

[0024] Fig.18 A flow chart of a control method for a battery pack charge and discharge equalization device provided in an embodiment of the utility model;

[0025] Fig.19 A schematic diagram of a specific flow chart of a control method for a battery pack charge and discharge equalization device provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] See also Figures 1 to 17 , Figure 1A schematic diagram of the structure of a battery pack charge and discharge balancing device provided in an embodiment of the utility model, wherein the battery pack charge and discharge balancing device 10 is electrically connected to a battery pack 20, the battery pack 20 includes a plurality of battery cells 201, the battery pack charge and discharge balancing device 10 includes a housing 11 and a control circuit board 15 disposed in the housing 11, the control circuit board 15 includes a plurality of balancing modules 151 and a controller 152, the balancing modules 151 correspond to the battery cells 201 one by one, each of the balancing modules 151 includes a battery cell information sampling circuit 1511, a charging circuit 1512 and a discharging circuit 1513, the battery cell information sampling circuit 151 is used to collect and obtain the battery cell information of the corresponding battery cell 201 ; The charging circuit 1512 is used to control the charging of the corresponding battery cell 201; the discharging circuit 1513 is used to control the discharging of the corresponding battery cell 201; wherein the battery cell information of the battery cell 201 includes the voltage information, current information and temperature information of the battery cell 201; the controller 152 is connected to the equalization module 151, and is used to control the operation of the equalization module 151, and is used to compare the battery cell information of the corresponding battery cell 201 acquired by the battery cell information sampling circuit 1511 with the preset equalization target voltage of the corresponding battery pack 20, obtain the voltage comparison result, and control the charging circuit 1512 or the discharging circuit 1513 of the equalization module 151 corresponding to the battery cell 201 to work according to the voltage comparison result. The housing 11 is provided with a plurality of equalization interface groups 12, and the equalization interface groups 12 correspond to and are connected to the equalization modules 151 one by one, and the battery pack charge and discharge equalization device 10 is connected to the battery pack 20 through the equalization interface groups 12. The balancing interface group 12 includes a battery cell positive electrode connection port, a battery cell negative electrode connection port and a ground connection port. The battery cell positive electrode connection port and the battery cell negative electrode connection port are respectively connected to the positive electrode and negative electrode of the corresponding battery cell through data lines, and the ground connection port is connected to the ground terminal through the data line.

[0028] Among them, one battery pack 20 is connected to one battery pack charge and discharge balancing device 10, and the balancing module 151 of the battery pack charge and discharge balancing device 10 corresponds to the battery cell of the battery pack 20 one by one, and the battery cell information sampling circuit 1511, the charging circuit 1512 and the discharging circuit 1512 of the balancing module 151 all correspond to the battery cell 201 one by one. The battery pack charge and discharge balancing device 10 may also include a charging overvoltage protection circuit, a charging undervoltage protection circuit, a discharging overvoltage protection circuit, a discharging undervoltage protection circuit, a charging low temperature protection circuit, a discharging low temperature protection circuit, a charging high temperature protection circuit and a discharging high temperature protection circuit to monitor the state of the battery cell 201 and ensure the safety and reliability of the battery cell 201. The battery pack charge and discharge equalization device 10 is electrically connected to the battery pack 20. A plurality of equalization modules 151 corresponding to a plurality of battery cells 201 of the battery pack 20 are arranged on the control circuit board 15 of the battery charge and discharge equalization device 10 to individually perform equalization operation control on each battery cell 201 so that each battery cell 201 can reach the equalization target voltage, thereby improving the utilization rate of the capacity of the battery cell 201. Each battery cell 201 can be independently equalized simultaneously, thereby improving the voltage consistency of the battery cell 201, thereby enabling the battery pack 20 as a whole to reach the equalization faster, thereby improving the efficiency and effect of the equalization, and the number and position of the battery cells 201 that are subjected to the equalization operation at a single time are not limited, thus having strong flexibility. Moreover, the equalization modules 151 correspond to the battery cells 201 one by one for equalization, thereby effectively improving the safety of the equalization. Each equalization module 151 and the battery cell 201 will not interfere with each other, thus being safer and more reliable. A controller 152 connected to the equalization module 151 is arranged on the control circuit board 15 so that the controller 152 is used to control the operation of each equalization module 151. The balancing module 151 includes a cell information sampling circuit 1511, a charging circuit 1512 and a discharging circuit 1513, and each cell 201 corresponds to an independent cell information sampling circuit 1511, a charging circuit 1512 and a discharging circuit 1513. The cell information sampling circuit 1511 cooperates with the controller 152 to realize the balancing trigger judgment of the corresponding cell 201. The charging circuit 1512 and the discharging circuit 1513 can be combined to balance the cell 201 by charging or discharging according to the sampling situation, so that the balancing operation is more accurate and reliable, and the heating problem and the long balancing time and low efficiency caused by only discharging balancing operation can be prevented. At the same time, overvoltage, undervoltage, low temperature and overheating detection can be performed according to the cell information of the collected cell 201 to realize overvoltage, undervoltage, low temperature and overheating protection of the cell 201, and the charging circuit 1512 and the discharging circuit 1513 of the balancing module 151 connected to the corresponding cell 201 can be turned off according to the detection result, and the alarm information is uploaded.In addition, by providing a shell 11 and providing a balancing interface group 12 on the shell, each battery cell 201 of the battery pack 20 is inserted into the corresponding balancing interface group 12 through a corresponding data line to be connected to the balancing module 151 of the battery pack charge and discharge balancing device 10, so that charge and discharge balancing can be performed according to the battery cell information sampling of the battery cell 201 through the data line connection. The battery pack charge and discharge balancing device 10 is independently provided separately from the battery pack 20. The maintenance of the battery pack charge and discharge balancing device 10 does not require the disassembly of the battery pack 20, which can reduce the maintenance intensity, save maintenance costs and maintenance work intensity, save maintenance time, improve maintenance efficiency, reduce production stoppage losses, and improve safety.

[0029] Preferably, each battery cell 201 of the battery pack 20 is electrically connected to a voltage sampling harness socket 21 through a connecting wire, the balancing interface group 12 of the battery pack charge and discharge balancing device 10 is connected to one end of the data cable, and the other end of the data cable is connected to the harness socket 101, and the harness socket 101 and the voltage sampling harness socket 21 can be plugged together to be electrically connected, then the harness socket 101 and the voltage sampling harness socket 21 can be plugged together to realize the connection between the battery pack charge and discharge balancing device 10 and the battery pack 20, so as to charge and discharge balance the each battery cell of the battery pack 20.

[0030] Preferably, the controller 152 is further used to calculate the capacity value of the corresponding battery cell 201 according to the battery cell information of the corresponding battery cell 201 acquired by the battery cell information sampling circuit 1511, and compare the calculated capacity value of the battery cell 201 with the preset charging capacity and preset discharging capacity of the corresponding battery cell 201 to obtain the capacity comparison result, and control the charging circuit 1512 or the discharging circuit 1513 of the equalization module 151 corresponding to the battery cell 201 to work according to the capacity comparison result. Among them, the capacity value of the battery cell 201 can be calculated according to the current information of the battery cell 201, and the calculated capacity value of the battery cell 201 is compared with the preset charging capacity and preset discharging capacity of the corresponding battery cell 201, so as to perform capacity balancing control later, realize the capacity balancing between the batteries 201 in the battery pack 20, and realize the capacity consistency of each battery pack 20, so as to better utilize the capacity of each battery cell 201, improve the utilization rate of the capacity of the battery cell 201, and effectively avoid the barrel effect caused by the inconsistent performance of the battery cell due to time and self-discharge.

[0031] Preferably, in some embodiments, a plurality of battery pack charge-discharge balancing devices 10 may be stacked in sequence, taking a battery cluster as a unit. Figure 7As shown, the cell voltage balancing function within the entire battery cluster can be performed, which can facilitate voltage balancing and capacity balancing between the battery groups 20, improve the voltage consistency and capacity consistency of the battery group 20, and improve the utilization rate of the cell capacity of the battery cluster. The battery cluster is composed of multiple battery groups 20. At this time, the number of battery group charge and discharge balancing devices 10 is the same as the number of battery groups 20 in the battery cluster. The battery group charge and discharge balancing devices 10 correspond to the battery groups 20 one by one, so as to perform balancing operations on each cell of the corresponding battery group 20 respectively.

[0032] Reference Figures 8 to 9 Specifically, in this embodiment, the controller 152 may be a single-chip microcomputer U1, and the model of the single-chip microcomputer U1 may be MT32F006C6PB. The cell information sampling circuit 1511 includes a digital current and power monitoring chip U6 of model TPA626 to sense the current of the cell and monitor the power. The digital current and power monitoring chip U6 is connected to the single-chip microcomputer U1 and the balancing interface group 12, so as to be connected to the corresponding cell through the balancing interface group 12 to detect and obtain the current information and power information of the cell, and transmit the detected current information and power information of the cell to the single-chip microcomputer U1, so that the cell information sampling circuit 1511 collects the cell information of the cell and transmits it to the controller 152, so that the controller 152 can perform balancing operation according to the collected cell information of the cell. Of course, in some embodiments, the battery cell information sampling circuit 1511 may adopt the single cell data acquisition circuit of the prior art, such as the single cell data acquisition circuit disclosed in Chinese patent CN201821575598.7, a single cell data acquisition circuit for a battery pack, which will not be described in detail here.

[0033] Continue to refer to Figures 1 to 17Specifically, the control circuit board 15 also includes a communication circuit, and a communication interface 13 is provided on the shell 11, and the communication interface 13 is electrically connected to the controller through the communication circuit. By setting the communication interface 13 to cooperate with the communication circuit to transmit data with the host computer or the control device of the battery pack 20 through the bus, the host computer or the control device of the battery pack 20 can be connected to the battery pack charge and discharge equalization device 10 through the bus in cooperation with the communication interface 13 to achieve data transmission and control. The user can read the cell information and charge and discharge status of the corresponding battery cell of the battery pack 20 through the host computer or the control device of the battery pack 20 in cooperation with the battery pack charge and discharge equalization device 10 corresponding to the communication interface 13 connected through the bus, and can also input and set the preset equalization target voltage, charge and discharge current value, preset overvoltage voltage threshold, preset undervoltage voltage threshold, preset low temperature temperature threshold, preset The overheat temperature threshold, the preset charging capacity of the battery cell 201 and the preset discharging capacity of the battery cell 201, the preset balancing target voltage of the battery pack 20, the charge and discharge current value, the preset overvoltage voltage threshold, the preset undervoltage voltage threshold, the preset low temperature temperature threshold, the preset overheat temperature threshold, the preset charging capacity of the battery cell 201 and the preset discharging capacity of the battery cell 201 can be transmitted to the communication circuit of the corresponding battery pack charge and discharge balancing device 10 via the bus and the communication interface, and then transmitted to the controller 152 for storage and recording, so as to facilitate the subsequent voltage balancing and capacity balancing between the battery cells in the battery pack 20, so as to achieve voltage consistency and capacity consistency of each battery pack 20, and perform overvoltage protection, undervoltage protection, low temperature protection and overheat protection on the battery cells of the battery pack. At the same time, a one-key balancing instruction can be issued to all the cells 201 of the battery pack 20 through the host computer and the control device of the battery pack 20, and the one-key balancing instruction is transmitted to the corresponding battery pack charge and discharge balancing device 10 through the communication interface 13. The controller 152 of the battery pack charge and discharge balancing device 10 performs corresponding balancing control according to the preset balancing target voltage of the battery pack 20, the preset charging capacity of the cell 201, the preset discharge capacity of the cell 201, and the cell information of each cell 201 collected and obtained by the circuit 1511. The control device of the battery pack 20 is used to realize the interaction between the battery pack and the user, so that the user can set the battery pack parameters and display the battery pack status. The control device of the battery pack 20 can be a main control screen set on the battery pack 20. The communication interface 13 can be an RS485 communication interface and / or a CAN communication interface, etc. Accordingly, the host computer or the control device of the battery pack 20 can be connected to the battery pack charge and discharge balancing device 10 through the RS485 bus and / or the CAN bus in conjunction with the corresponding communication interface 13.The communication circuit includes a transceiver, which is connected to the communication interface 13 and the controller 152. When the communication interface 13 is an RS485 communication interface, the transceiver adopts an isolated RS485 transceiver U5 with model CA-IS3082; when the communication interface 13 is a CAN communication interface, the transceiver adopts an isolated CAN transceiver U4 with model CA-IS3052G, such as. Fig.10 shown.

[0034] Specifically, the shell 11 is provided with a power input interface 14, and the power input interface 14 is connected to the charging circuit 1512. The charging circuit 1512 includes an AC / DC module and a DC / DC step-down module. The input end and the output end of the AC / DC module are respectively connected to the power input interface 14 and the input end of the DC / DC step-down module. The output end of the DC / DC step-down module is connected to the balancing interface group 12 to convert the external input AC power into DC power and then transmit it to the DC / DC step-down module. The DC power output by the AC / DC module is stepped down to a stable voltage range required for battery cell charging through the DC / DC step-down module, and then the voltage is output. The output voltage is transmitted to the battery cell electrically connected to the balancing interface group 12 for charging through the balancing interface group 12. The power input interface 14 is connected to the charging circuit 1512 of all the balancing modules 151. The power input interface 14 is used to connect the battery pack charging and discharging balancing device 10 to the mains. The mains can be 220V AC. Through the cooperation of the AC / DC module and the DC / DC module, the charging circuit 1512 can convert the 220V AC into DC and then reduce the voltage to the stable voltage required for charging the battery cell. The stable voltage required for charging the battery cell can be 3.65V.

[0035] Combination Fig.11 Specifically, the DC / DC step-down module includes a DC / DC converter U2 and a voltage regulator U3, the voltage input pin of the DC / DC converter U2 is connected to the cathode of the second diode D2, the anode of the second diode D2 is connected to the fuse F1 for protection, the voltage positive output pin of the DC / DC converter U2 is connected to the input pin of the voltage regulator U3, and the output pin of the voltage regulator U3 can be electrically connected to a ninth grounding capacitor C9 and a tenth grounding capacitor C10 connected in parallel with each other.

[0036] Combination Figures 12 to 17Specifically, the balancing module 151 also includes a buck-boost charge and discharge controller U7, which is connected to the corresponding battery cell through a connecting switch tube and an inductor L3, so as to control the charging or discharging of the battery cell by controlling the on and off of the connecting switch tube. The buck-boost charge and discharge controller U7 is connected to the charging circuit 1512 and the discharging circuit 1513. The charging circuit 1512 includes a charging switch control unit, and the input end of the charging switch control unit is connected to the controller 152. The output end of the charging switch control unit is connected to the feedback pin of the buck-boost charge and discharge controller U7 and the connecting switch tube, so that the charging switch control unit is turned on or off according to the control of the controller 152, thereby controlling the start and stop of the charging control of the buck-boost charge and discharge controller U7, so as to control the on or off of the connecting switch tube, and realize the start and stop of the charging of the battery cell.

[0037] Preferably, the charging switch control unit includes a first switch tube Q1 and a second switch tube Q2, the single-chip computer U1 is connected to the gate of the second switch tube Q2 through the first switch tube Q1, the drain of the second switch tube Q2 serves as the output end of the charging switch control unit and is connected to the feedback pin of the buck-boost charge and discharge controller U7 and the connecting switch tube, and the source of the second switch tube Q2 is connected to the 5V power supply voltage.

[0038] Specifically, the discharge circuit 1513 includes a discharge resistor R15 and a discharge switch tube Q5, the gate of the discharge switch tube Q5 is connected to the controller 152, that is, the gate of the discharge switch tube Q5 is connected to the single-chip computer U1, the source of the discharge switch tube Q5 is grounded, and the drain of the discharge switch tube Q5 is connected to the feedback pin of the buck-boost charge-discharge controller U7 and the connection switch tube through the discharge resistor R15, so that the discharge switch tube Q5 is turned on or off according to the control of the controller 152, so that the discharge resistor R15 is connected to the buck-boost charge-discharge controller U7 and the connection switch tube, and can control the start and stop of the discharge control of the buck-boost charge-discharge controller U7, so as to control the conduction or cutoff of the connection switch tube, and realize the start and stop of the discharge of the battery cell. A sixteenth resistor R16 is electrically connected between the single-chip computer U1 and the gate of the discharge switch tube Q5, and a seventeenth grounding resistor R17 is electrically connected between the sixteenth resistor R16 and the gate of the discharge switch tube Q5.

[0039] Preferably, there may be four connecting switch tubes, namely, a third connecting switch tube Q3, a sixth connecting switch tube Q6, a seventh connecting switch tube Q7 and a fourth connecting switch tube Q4. The gates of the third connecting switch tube Q3, the sixth connecting switch tube Q6, the seventh connecting switch tube Q7 and the fourth connecting switch tube Q4 are all connected to the buck-boost charge and discharge controller U7. The drain of the third connecting switch tube Q3 is connected to the output end of the charging switch control unit and the discharge circuit. The source of the third connecting switch tube Q3 is connected to the drain of the sixth connecting switch tube Q6. The source of the sixth connecting switch tube Q6 is connected to the source of the seventh connecting switch tube Q7. The drain of the seventh connecting switch tube Q7 is connected to one end of the inductor L3 and the source of the fourth connecting switch tube. The other end of the inductor L3 is connected to the drain of the sixth connecting switch tube Q6. The drain of the fourth connecting switch tube Q4 is connected to the corresponding battery cell after passing through the fourteenth resistor R14.

[0040] Of course, in some embodiments, the charging circuit 1512 may adopt a charging circuit of the prior art, such as the charging circuit disclosed in Chinese patent CN201820026451.6, a charging circuit with a protection function, and the discharging circuit 1513 may also adopt a discharging circuit of the prior art, such as the discharge circuit disclosed in Chinese patent CN201510274099.9, a battery management system balanced discharge circuit, or the execution circuit disclosed in Chinese patent CN200520070189.8, a lithium rechargeable battery charge and discharge balanced circuit, which will not be repeated here.

[0041] Specifically, the controller 152 can be connected to the buck-boost charge and discharge controller U7 through a chip enable circuit, and the chip enable circuit includes an eighth switch tube Q8. The controller 152 is connected to the gate of the eighth switch tube Q8 and the thirtieth grounding resistor R30 through a twenty-ninth resistor R29. The source of the eighth switch tube Q8 is grounded, and the drain of the eighth switch tube Q8 is connected to the enable input pin CE of the buck-boost charge and discharge controller U7.

[0042] Specifically, the controller 152 can be connected to the buck-boost charge-discharge controller U7 through a current dynamic control circuit to perform current dynamic control according to the current information of the battery cell actually collected to improve safety. The current dynamic control circuit includes a ninth switch tube Q9, and the controller 152 is connected to the gate of the ninth switch tube Q9 and the thirty-ninth grounding resistor R39 through the thirty-seventh resistor R37. The source of the ninth switch tube Q9 is grounded, and the drain of the ninth switch tube Q9 is connected to the current control pin IPWM of the buck-boost charge-discharge controller U7.

[0043] Specifically, the controller 152 can be connected to the buck-boost charge-discharge controller U7 through a charge-discharge direction control circuit to control the charge-discharge direction. The charge-discharge direction control circuit includes a tenth switch tube Q10, the controller 152 is connected to the gate of the tenth switch tube Q10 and the fifty-first grounding resistor R51 through a fiftieth resistor R50, the source of the tenth switch tube Q10 is grounded, and the drain of the tenth switch tube Q10 is connected to the direction pin DIR of the buck-boost charge-discharge controller U7.

[0044] Specifically, the housing 11 is provided with a socket screen 18 , and the socket screen 18 is electrically connected to the controller. The socket screen 18 may be located on the top surface of the housing 11 .

[0045] Specifically, a fan is provided on the control circuit board, and a ventilation hole 111 is provided on the housing 11 corresponding to the fan, and the fan faces the ventilation hole 111 to further dissipate heat for the battery pack charge and discharge balancing device 10 to prevent the device from being overheated and damaging the components in the device. There can be multiple fans, and they are evenly spaced on the control circuit board.

[0046] The housing 11 is also provided with an Ethernet interface 16, which is electrically connected to the controller and can be connected to the host computer for communication, so that the battery pack charge and discharge equalization device 10 can be controlled by the software installed on the host computer. A handle 17 can be provided on one side of the housing 11 for easy carrying and placement. The handle 17, the equalization interface group 12 and the communication interface 13 are all provided on different sides of the housing 11.

[0047] Specifically, the flow chart of the control method of the battery pack charge and discharge equalization device 10 is as follows: Fig.18 As shown, the control method includes the following steps:

[0048] Step S11, cell information sampling: the cell information sampling circuit collects and obtains the cell information of the corresponding cell; wherein the cell information of the cell includes the voltage information, current information and temperature information of the cell;

[0049] Step S12, voltage comparison: the controller compares the cell information of the corresponding cell acquired by the cell information sampling circuit with the preset equalization target voltage of the corresponding battery pack to obtain a voltage comparison result; wherein, the cell information of the cell includes the voltage information of the cell, and the voltage information of the cell is compared with the preset equalization target voltage of the battery pack corresponding to the cell, so as to perform energy equalization operation of the cell later. Moreover, the cell status can also be monitored according to the cell information acquired, so as to perform overvoltage, undervoltage, low temperature and overtemperature protection, and ensure the safety and reliability of the cell operation.

[0050] Step S13, voltage balancing control: controlling the charging circuit or the discharging circuit of the balancing module corresponding to the battery cell to operate according to the voltage comparison result.

[0051] Specifically, before step S11, the following steps may also be included:

[0052] The controller receives and stores a preset equalization target voltage of the battery pack.

[0053] Preferably, before step S12, the following steps may also be included:

[0054] The controller determines whether the preset balanced target voltage of the battery pack corresponding to the battery cell is recorded. If so, step S12 is executed. If not, the controller waits to receive the preset balanced target voltage of the battery pack.

[0055] Specifically, the step S13 includes:

[0056] When the voltage comparison result is that the collected voltage information of the battery cell exceeds the preset equalization target voltage and the preset voltage difference of the corresponding battery pack, the controller controls the charging circuit of the equalization module corresponding to the battery cell to operate;

[0057] When the voltage comparison result is that the preset equalization target voltage of the corresponding battery pack exceeds the preset voltage difference of the collected voltage information of the battery cell, the controller controls the discharge circuit of the equalization module corresponding to the battery cell to operate.

[0058] Among them, the preset voltage difference can be 50mV. When the voltage comparison result is that the difference between the collected voltage information of the battery cell and the preset balanced target voltage of the corresponding battery pack exceeds 50mV, the controller controls the charging circuit of the balanced module corresponding to the battery cell to control the corresponding battery cell to charge; when the voltage comparison result is that the difference between the preset balanced target voltage of the corresponding battery pack and the collected voltage information of the battery cell exceeds 50mV, the controller controls the discharge circuit of the balanced module corresponding to the battery cell to control the corresponding battery cell to discharge. During the charging and discharging process, the battery cell information sampling circuit still collects the battery cell information of the battery cell in real time, so as to control the start and stop of the charging circuit and the discharge circuit according to the voltage information of the battery cell in real time, so as to achieve voltage balance and prevent excessive charging or discharging. The preset voltage difference can be set according to actual needs.

[0059] The step S13 further includes: when the voltage comparison result shows that the difference between the voltage information of the battery cell and the preset equalization target voltage of the corresponding battery pack does not exceed the preset voltage difference, the controller controls the charging circuit and the discharging circuit of the equalization module corresponding to the battery cell to not work.

[0060] Combination Fig.19 Specifically, the step S11 further includes:

[0061] Step S120, capacity comparison: the controller calculates the capacity value of the corresponding battery cell according to the battery cell information of the corresponding battery cell collected by the battery cell information sampling circuit, and compares the calculated capacity value of the battery cell with the preset charging capacity and preset discharging capacity of the corresponding battery cell to obtain the capacity comparison result, and controls the charging circuit or discharging circuit of the balancing module corresponding to the battery cell to operate according to the capacity comparison result.

[0062] Specifically, before step S11, the following steps may also be included:

[0063] The controller receives and stores the preset charging capacity and the preset discharging capacity of the battery cell.

[0064] The step of controlling the charging circuit or the discharging circuit of the equalization module corresponding to the battery cell according to the capacity comparison result in step S120 is specifically as follows:

[0065] When the capacity comparison result shows that the capacity value of the battery cell is less than the preset charging capacity of the corresponding battery cell, the controller controls the charging circuit of the balancing module corresponding to the battery cell to operate, so as to control the corresponding battery cell to be charged;

[0066] When the capacity comparison result shows that the capacity value of the battery cell is greater than the preset discharge capacity of the corresponding battery cell, the discharge circuit of the equalization module corresponding to the battery cell is controlled to operate so as to control the corresponding battery cell to discharge;

[0067] When the capacity comparison result is that the capacity value of the battery cell is not less than the preset charging capacity of the corresponding battery cell and the capacity comparison result is that the capacity value of the battery cell is not greater than the preset discharge capacity of the corresponding battery cell, the controller controls the charging circuit and the discharging circuit of the balancing module corresponding to the battery cell to not work.

[0068] In summary, the battery pack charge and discharge balancing device of the utility model is electrically connected to the battery pack, and a plurality of balancing modules corresponding to a plurality of battery cells of the battery pack are arranged on the control circuit board of the battery charge and discharge balancing device to control the balancing operation of each battery cell individually so that each battery cell can reach the balanced target voltage, thereby improving the utilization rate of the capacity of the battery cell, and each battery cell can be independently balanced simultaneously, which can improve the consistency of the battery cell voltage, so that the battery pack as a whole can reach the balance faster, and the efficiency and effect of the balance can be improved, and the number and position of the battery cells for a single balancing operation are not limited, and the flexibility is strong, and the balancing module corresponds to the battery cell one by one for balancing, which can effectively improve the safety of the balancing, and the balancing modules and the battery cells will not interfere with each other, which is safer and more reliable; a controller connected to the balancing module is arranged on the control circuit board, so as to adopt the controller Control the work of each balancing module, and the balancing module includes a battery cell information sampling circuit, a charging circuit and a discharging circuit. Each battery cell has an independent battery cell information sampling circuit, a charging circuit and a discharging circuit. The battery cell information sampling circuit is used in conjunction with the controller to realize the balancing trigger judgment of the corresponding battery cell. The charging circuit and the discharging circuit can be combined to balance the battery cell by charging or discharging according to the sampling situation, so that the balancing operation is more accurate and reliable, and the heating problem and the long balancing time and low efficiency caused by only discharging balancing operation can be prevented. At the same time, overvoltage, undervoltage, low temperature and overheating detection can be performed based on the collected battery cell information to realize overvoltage, undervoltage, low temperature and overheating protection of the battery cell, and the charging circuit and the discharging circuit of the balancing module connected to the corresponding battery cell can be shut down according to the detection results, and the alarm information can be uploaded. In addition, by providing a shell and providing a balancing interface group on the shell, each battery cell of the battery pack is inserted into the corresponding balancing interface group through the corresponding data line to be connected with the balancing module of the battery pack charge and discharge balancing device, so that charge and discharge balancing can be performed according to the cell information sampling of the battery cell through the data line connection. The battery pack charge and discharge balancing device is independently provided separately from the battery pack. The battery pack charge and discharge balancing device does not need to disassemble the battery pack for maintenance, which can reduce maintenance intensity, save maintenance cost and maintenance work intensity, save maintenance time, improve maintenance efficiency, reduce production stoppage losses, and improve safety.

[0069] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A battery pack charge and discharge equalization device, characterized in that: The battery pack includes a plurality of battery cells, and the battery pack charge and discharge balancing device includes a shell and a control circuit board arranged in the shell, and the control circuit board includes a plurality of balancing modules and a controller, and the balancing modules correspond to the battery cells one by one, and each of the balancing modules includes a battery cell information sampling circuit for collecting and acquiring the battery cell information of the corresponding battery cell, a charging circuit for controlling the charging of the corresponding battery cell, and a discharge circuit for controlling the discharge of the corresponding battery cell; wherein the battery cell information includes the voltage information, current information and temperature information of the battery cell; the controller is connected to the balancing module; a plurality of balancing interface groups are arranged on the shell, and the balancing interface groups correspond to and are connected to the balancing modules one by one, and the battery pack charge and discharge balancing device is connected to the battery pack through the balancing interface group; the balancing interface group includes a battery cell positive electrode connection port, a battery cell negative electrode connection port and a ground connection port, and the battery cell positive electrode connection port and the battery cell negative electrode connection port are respectively connected to the positive electrode and negative electrode of the corresponding battery cell through a data line, and the ground connection port is connected to the ground end through a data line.

2. The battery pack charge and discharge equalization device according to claim 1, characterized in that: The control circuit board also includes a communication circuit. The housing is provided with a communication interface, and the communication interface is electrically connected to the controller through the communication circuit.

3. The battery pack charge and discharge equalization device according to claim 1, characterized in that: The shell is provided with a power input interface, and the power input interface is connected to the charging circuit. The charging circuit includes an AC / DC module and a DC / DC step-down module. The input end and the output end of the AC / DC module are respectively connected to the power input interface and the input end of the DC / DC step-down module, and the output end of the DC / DC step-down module is connected to the balancing interface group.

4. The battery pack charge and discharge equalization device according to claim 1, characterized in that: The balancing module also includes a buck-boost charge and discharge controller, which is connected to the corresponding battery cell through a connecting switch tube and an inductor, and is connected to the charging circuit and the discharging circuit. The charging circuit includes a charging switch control unit, and the input end of the charging switch control unit is connected to the controller, and the output end of the charging switch control unit is connected to the feedback pin of the buck-boost charge and discharge controller and the connecting switch tube.

5. The battery pack charge and discharge equalization device according to claim 4, characterized in that: The discharge circuit includes a discharge resistor and a discharge switch tube, the gate of the discharge switch tube is connected to the controller, the source of the discharge switch tube is grounded, and the drain of the discharge switch tube is connected to the feedback pin of the buck-boost charge and discharge controller and the connecting switch tube through the discharge resistor.

6. The battery pack charge and discharge equalization device according to claim 1, characterized in that: A socket screen is provided on the shell, and the socket screen is electrically connected to the controller.

7. The battery pack charge and discharge equalization device according to claim 1, characterized in that: The control circuit board is provided with a fan, and the shell is provided with ventilation holes corresponding to the fan.

8. The battery pack charge and discharge equalization device according to claim 1, characterized in that: The housing is provided with an Ethernet interface, and the Ethernet interface is electrically connected to the controller.

9. The battery pack charge and discharge equalization device according to claim 1, characterized in that: A handle is provided on one side surface of the shell.

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