Series-parallel connection switching circuit for battery charging and discharging and electronic equipment

Abstract

The utility model relates to a series-parallel connection switching circuit for battery charging and discharging and electronic equipment, the circuit comprises a control module, a phase inverter, a change-over switch group and a plurality of battery cells of a battery, the control module is connected with the phase inverter and the change-over switch group, the phase inverter is connected with the change-over switch group, the change-over switch group is connected with the plurality of battery cells, and the control module is connected with the control module. The plurality of battery cells are connected with the control module, the control module is used for outputting level signals to the phase inverter according to charging and discharging states, the phase inverter is used for receiving the level signals and inverting the level signals, and the change-over switch group is used for controlling the plurality of battery cells to be connected in series in a charging state according to the output of the phase inverter and the level signals output by the control module. And parallel connection in a discharge state. The series-parallel connection state of each battery cell is switched according to the charging and discharging state of the battery, the series connection charging can reduce the charging current, the parallel connection discharging can increase the discharging rate, and the problem that the battery cannot meet the fast charging requirement and the high-power discharging requirement due to the fixed battery cell series-parallel connection mode is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a series-parallel switching circuit for battery charging and discharging and an electronic device. Background Art

[0002] Batteries have the advantages of high energy density, high power density, many cycle usage times, long storage time, etc., and are thus widely used in daily life. Currently, the conventional battery design is to simply set multiple battery cells in a fixed series-parallel manner to meet specific voltage or current requirements. This fixed design makes it impossible for the battery pack to dynamically change its series-parallel state during charging and discharging. Obviously, the fixed series-parallel manner of battery cells causes the battery to be unable to meet both the fast charging requirement and the high-power discharging requirement.

[0003] In view of the above problems, no effective solution has been proposed yet. Summary of the Utility Model

[0004] This application provides a series-parallel switching circuit for battery charging and discharging and an electronic device to solve the above technical problem that "the fixed series-parallel manner of battery cells causes the battery to be unable to meet both the fast charging requirement and the high-power discharging requirement".

[0005] According to one aspect of the embodiments of this application, a series-parallel switching circuit for battery charging and discharging is provided, including: a control module, an inverter, a switching switch group, and multiple battery cells of the battery. The control module is connected to the inverter and the switching switch group, the inverter is connected to the switching switch group, the switching switch group is connected to the multiple battery cells, and the multiple battery cells are connected to the control module. The control module is used to output a level signal to the inverter according to the charging and discharging states. The inverter is used to receive the level signal and invert the level signal. The switching switch group is used to control the multiple battery cells to be in series during the charging state and in parallel during the discharging state according to the output of the inverter and the level signal output by the control module.

[0006] Optionally, the control module is used to output a low level signal to the inverter through the status output pin when the battery is in the charging state, and output a high level signal to the inverter through the status output pin when the battery is in the discharging state.

[0007] Optionally, the circuit further includes multiple voltage acquisition devices. One end of each voltage acquisition device is connected to the positive electrode of each battery cell among the multiple battery cells, and the other ends of the respective voltage acquisition devices are respectively connected to the respective voltage acquisition pins of the control module. The voltage acquisition device is used to acquire the voltage of the battery cell and transmit the voltage to the control module.

[0008] Optionally, the inverter includes a first MOS transistor and a second MOS transistor. The gates of the first MOS transistor and the second MOS transistor are both connected to the status output pin of the control module. The first MOS transistor is configured to turn off when receiving a low-level signal transmitted by the control module, and is also configured to turn on when receiving a high-level signal transmitted by the control module, and output an inverted low-level signal through its source. The second MOS transistor is configured to turn on when receiving a low-level signal transmitted by the control module, and output an inverted high-level signal through its drain, and is also configured to turn off when receiving a high-level signal transmitted by the control module.

[0009] Optionally, the switching switch group includes a first switch group and a second switch group. The first switch group is connected to the control module and multiple battery cells. The second switch group is connected to the control module, the inverter and multiple battery cells. Each MOS transistor of the first switch group turns off when the control module outputs a low-level signal, and turns on when the control module outputs a high-level signal. Each MOS transistor of the second switch group turns on when the control module outputs a low-level signal, and turns off when the control module outputs a high-level signal.

[0010] Optionally, the multiple battery cells include a first battery cell, a second battery cell, a third battery cell and a fourth battery cell. The first battery cell, the second battery cell, the third battery cell and the fourth battery cell are connected in series in sequence under the charging state. The series branch where the first battery cell and the second battery cell are located is connected in parallel with the series branch where the third battery cell and the fourth battery cell are located under the discharging state.

[0011] Optionally, the first switch group includes a third MOS transistor, a fourth MOS transistor, a fifth MOS transistor, a sixth MOS transistor and a seventh MOS transistor. The gate of the third MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the third battery cell, and the source is connected to the negative electrode of the first battery cell. The gate of the fourth MOS transistor is connected to the status output pin of the control module, the drain is connected to the positive electrode of the fourth battery cell, and the source is connected to the positive electrode of the second battery cell. The gate of the fifth MOS transistor is connected to the status output pin of the control module, the drain is connected to the first voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through a first voltage acquisition device. The gate of the sixth MOS transistor is connected to the status output pin of the control module, the drain is connected to the second voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through a first voltage acquisition device. The gate of the seventh MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the fourth battery cell, and the source is connected to the positive electrode of the first battery cell.

[0012] Optionally, the second switch group includes a third switch group, an eighth MOS transistor, and a ninth MOS transistor. The third switch group is respectively connected to the output terminal of the inverter, the negative electrode of the third battery cell, and the positive electrode of the second battery cell. The gate of the eighth MOS transistor is connected to the status output pin of the control module, the source is connected to the first voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the third battery cell through a second voltage acquisition device. The gate of the ninth MOS transistor is connected to the status output pin of the control module, the source is connected to the second voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the fourth battery cell through a third voltage acquisition device.

[0013] Optionally, the circuit further includes a first resistor connected to the control module, and the control module is configured to determine the charge and discharge status of the battery according to the voltage drop across the first resistor.

[0014] Optionally, the circuit further includes a second resistor. One end of the second resistor is respectively connected to the gates of the fifth MOS transistor, the sixth MOS transistor of the first switch group, and the gate of the ninth MOS transistor of the second switch group. The second resistor is used to reduce the oscillation when the fifth MOS transistor, the sixth MOS transistor, and the ninth MOS transistor switch between conduction and cutoff.

[0015] Optionally, the circuit further includes a protection device respectively connected to the control module and the load, and is used to prevent the reverse current from flowing to the load.

[0016] According to another aspect of the embodiments of the present application, the present application further provides an electronic device, and the electronic device includes the above series-parallel switching circuit for battery charge and discharge.

[0017] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the related technologies:

[0018] The present application provides a series-parallel switching circuit for battery charge and discharge, including: a control module, an inverter, a switching switch group, and multiple battery cells of the battery. The control module is connected to the inverter and the switching switch group, the inverter is connected to the switching switch group, the switching switch group is connected to the multiple battery cells, and the multiple battery cells are connected to the control module. The control module is configured to output a level signal to the inverter according to the charge and discharge status. The inverter is configured to receive the level signal and invert the level signal. The switching switch group is configured to control the multiple battery cells to be in series during the charging state and in parallel during the discharging state according to the output of the inverter and the level signal output by the control module. By switching the series-parallel state of each battery cell according to the charge and discharge status of the battery, series charging can reduce the charging current, and parallel discharging can increase the discharge rate, solving the problem that the fixed series-parallel method of battery cells cannot meet both the fast charging requirement and the high-power discharging requirement of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings herein are incorporated into and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application or in the related art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the related art. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 Schematic diagram of an optional series - parallel switching circuit for battery charging and discharging provided according to an embodiment of the present application;

[0022] Figure 2 Schematic diagram of another optional series - parallel switching circuit for battery charging and discharging provided by the present application;

[0023] Figure 3 Schematic diagram of an optional cell connection provided by the present application;

[0024] Figure 4 Schematic diagram of an optional circuit in the charging state provided by the present application;

[0025] Figure 5 Schematic diagram of an optional circuit in the discharging state provided by the present application. Detailed implementation manners

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0027] In subsequent descriptions, suffixes such as "module", "component", or "unit" used to represent elements are only for the convenience of description of the present application, and have no specific meaning in themselves. Therefore, "module" and "component" can be used interchangeably.

[0028] The battery has the advantages of high energy density, high power density, many cycle usage times, long storage time, etc., and is thus widely used in daily life. The current conventional battery designs all set multiple battery cells in a single fixed series-parallel manner to meet specific voltage or current requirements. This fixed design makes it impossible for the battery pack to dynamically change its series-parallel state during charging and discharging. Obviously, the fixed series-parallel manner of the battery cells causes the battery to be unable to meet both the fast charging requirement and the high-power discharging requirement.

[0029] To solve the problems mentioned in the background art, according to one aspect of the embodiments of the present application, there is provided a series-parallel switching circuit for battery charging and discharging, as Figure 1 shown, including: a control module 102, an inverter 104, a switching switch group 106, and multiple battery cells 108 of the battery.

[0030] The control module 102 is connected to the inverter 104 and the switching switch group 106. The inverter 104 is connected to the switching switch group 106. The switching switch group 106 is connected to the multiple battery cells 108. The multiple battery cells 108 are connected to the control module 102. The control module 102 is configured to output a level signal to the inverter 104 according to the charging and discharging states. The inverter 104 is configured to receive the level signal and invert the level signal. The switching switch group 106 is configured to control the multiple battery cells 108 to be in series during the charging state and in parallel during the discharging state according to the output of the inverter 104 and the level signal output by the control module 102.

[0031] The series-parallel switching circuit provided by the present application is used to switch the connection mode of each battery cell according to the charging and discharging states of the battery. In the charging state, the series connection of each battery cell can reduce the charging current. In the discharging state, the parallel connection of each battery cell can increase the discharging rate. In this way, by flexibly switching the series-parallel mode according to the charging and discharging states, both the fast charging requirement and the high-power discharging requirement can be met.

[0032] The control module is used to directly or indirectly control the switching of the MOS transistors (Metal-Oxide-Semiconductor Field-Effect Transistors) of the entire circuit. By the conduction and cutoff of each MOS transistor, the series-parallel switching of each battery cell can be achieved.

[0033] The switching switch group includes multiple MOS transistors. Each MOS transistor can be conducted or cut off according to the received level signal. Since the MOS transistors are connected to each battery cell in the connection mode provided by the present application, the conduction and cutoff of each MOS transistor can determine the connection mode of each battery cell, thereby realizing the control that the multiple battery cells are in series during the charging state and in parallel in pairs during the discharging state.

[0034] Figure 2 This is a schematic diagram of a series - parallel switching circuit for battery charging and discharging provided by this application. Next, the schematic diagram will be described.

[0035] As shown in the figure, it includes 4 battery cells, namely Cell1, Cell2, Cell3, and Cell4, which are respectively connected to 4 voltage acquisition devices, VC1, VC2, VC3, and VC4. The 4 voltage acquisition devices are respectively connected to 4 voltage acquisition pins, namely pin1, pin2, pin3, and pin4.

[0036] The control module U1 is a Gas Guage IC. There are 4 voltage acquisition pins, 1 status output pin (i.e., P - Chg), 1 discharge output pin (i.e., Do), and 1 charge output pin (i.e., Co) on U1.

[0037] One end of the protection device is connected to U1, and the other end is connected to the battery positive electrode P +. The protection device is composed of 2 MOS transistors (Q11 and Q12). Among them, the gate of Q11 is connected to the charge output pin Co, and the gate of Q12 is connected to the discharge output pin Do.

[0038] The inverter includes two MOS transistors, Q9 and Q10. The gates of Q9 and Q10 are both connected to the status output pin of U1. The output end of the inverter is Co1.

[0039] The switching switch group includes a first switch group and a second switch group. Among them, the first switch group includes 5 MOS transistors (namely Q1, Q2, Q4, Q6, and Q8), and the second switch group includes 1 third switch group (Q3) and 2 MOS transistors (Q5 and Q7). The gate of Q1 is connected to the output terminal of the inverter, the source is connected to the negative electrode of Cell1, and the drain is connected to the negative electrode of Cell3. The gate of Q2 is connected to the output terminal of the inverter, the drain is connected to the positive electrode of Cell4, and the source is connected to the positive electrode of Cell2. The gate of Q4 is connected to the status output pin P-Chg of U1, the drain is connected to pin 3 of the control module (i.e., the first voltage acquisition pin below), and the source is connected to the positive electrode of Cell2 through VC2 (i.e., the first voltage acquisition device below). The gate of Q6 is connected to the status output pin P-Chg of U1, the drain is connected to pin 4 of U1 (i.e., the second voltage acquisition pin below), and the source is connected to the positive electrode of Cell2 through VC2. The gate of Q8 is connected to the status output pin P-Chg of U1, the drain is connected to the negative electrode of Cell4, and the source is connected to the positive electrode of Cell1. The gate of Q5 is connected to the status output pin P-Chg of U1, the source is connected to pin 3 of the control module, and the drain is connected to the positive electrode of Cell3 through VC3 (i.e., the second voltage acquisition device below). The gate of Q7 is connected to the status output pin P-Chg of U1, the source is connected to pin 4 of U1, and the drain is connected to the positive electrode of Cell4 through VC4 (i.e., the third voltage acquisition device below).

[0040] As an optional embodiment, the control module is used to output a low-level signal to the inverter through the status output pin when the battery is in the charging state, and output a high-level signal to the inverter through the status output pin when the battery is in the discharging state.

[0041] The control module in this application is a fuel gauge IC. The corresponding control logic is pre-configured in the fuel gauge IC (that is, when it is detected that the battery is in the charging state, a low-level signal is output to the inverter through the status output pin, and when it is detected that the battery is in the discharging state, a high-level signal is output to the inverter through the status output pin), so that the fuel gauge IC can not only integrate analog circuits and digital circuits, but also implement control functions.

[0042] The inverter is connected to the status output pin of the control module. The control module is pre-configured with the corresponding control logic. By first monitoring the charge and discharge state of the battery, and then outputting the corresponding level signal to the inverter according to the current charge and discharge state.

[0043] When the battery is in the charging state, the control module outputs a low-level signal to the inverter through the status output pin. At this time, the inverter inverts the high-level signal output by the control module and outputs a high-level signal. At the same time, when the battery is in the charging state, the control module also transmits a low-level signal to the gates of the MOS transistors in the first switch group of the switching switch group through the status output pin, so that the MOS transistors in the first switch group are turned off. The specific implementation process will be described below.

[0044] When the battery is in the discharging state, the control module outputs a high-level signal to the inverter through the status output pin. At this time, the inverter inverts the low-level signal output by the control module and outputs a low-level signal. At the same time, when the battery is in the discharging state, the control module also transmits a high-level signal to the gates of the MOS transistors in the first switch group of the switching switch group through the status output pin, so that the MOS transistors in the first switch group are turned on. The specific implementation process will be described below.

[0045] As an alternative embodiment, the circuit further includes a plurality of voltage acquisition devices. One end of each voltage acquisition device is connected to the positive electrode of each cell in the plurality of cells, and the other ends of the respective voltage acquisition devices are respectively connected to the respective voltage acquisition pins of the control module. The voltage acquisition device is used to acquire the voltage of the cell and transmit the voltage to the control module.

[0046] Each cell is connected to a voltage acquisition device, and each voltage acquisition device is connected to a voltage acquisition pin of the control module. After the voltage acquisition device acquires the cell voltage, it sends the cell voltage to the control module so that the control module can perform subsequent calculations.

[0047] This application provides a sampling wire as the voltage acquisition device, and the sampling wire can be used for voltage acquisition and monitoring of the battery.

[0048] As an alternative embodiment, the inverter includes a first MOS transistor and a second MOS transistor. The gates of the first MOS transistor and the second MOS transistor are both connected to the status output pin of the control module. The first MOS transistor is used to turn off when receiving the low-level signal transmitted by the control module. The first MOS transistor is also used to turn on when receiving the high-level signal transmitted by the control module and output an inverted low-level signal through the source electrode. The second MOS transistor is used to turn on when receiving the low-level signal transmitted by the control module and output an inverted high-level signal through the drain electrode. The second MOS transistor is also used to turn off when receiving the high-level signal transmitted by the control module.

[0049] The inverter provided by this application is composed of a first MOS transistor and a second MOS transistor.

[0050] When the second MOS transistor receives the low-level signal output by the control module, since the source of the second MOS transistor is grounded, the gate voltage is higher than the source at this time, and the second MOS transistor remains in the conducting state.

[0051] The inverter is used to invert the level signal output by the control module and can jointly control the opening and closing of each MOS transistor in the switching switch group with the control module. It can be understood that the control module directly controls the opening and closing of some MOS transistors through the output level signal, and then indirectly controls the opening and closing of another part of the MOS transistors through the inverted signal output by the inverter, enabling flexible switching of the series-parallel connections of each battery cell.

[0052] As an alternative embodiment, the switching switch group includes a first switch group and a second switch group. The first switch group is connected to the control module and multiple battery cells, and the second switch group is connected to the control module, the inverter, and multiple battery cells. Each MOS transistor in the first switch group is turned off when the control module outputs a low-level signal and is turned on when the control module outputs a high-level signal. Each MOS transistor in the second switch group is turned on when the control module outputs a low-level signal and is turned off when the control module outputs a high-level signal.

[0053] Among the MOS transistors in the first switch group, there are both P-type MOS transistors and N-type MOS transistors. The gates of each MOS transistor in the first switch group are all connected to the status output pins of the control module. Therefore, when the control module outputs a low-level signal, each MOS transistor in the first switch group is turned off, and when the control module outputs a high-level signal, each MOS transistor in the first switch group is turned on.

[0054] Among the MOS transistors in the second switch group, there are both P-type MOS transistors and N-type MOS transistors. When the control module outputs a low-level signal, each MOS transistor in the second switch group is turned on, and when the control module outputs a high-level signal, each MOS transistor in the second switch group is turned off.

[0055] As an alternative embodiment, the multiple battery cells include a first battery cell, a second battery cell, a third battery cell, and a fourth battery cell. The first battery cell, the second battery cell, the third battery cell, and the fourth battery cell are connected in series in sequence during the charging state, and the series branch where the first battery cell and the second battery cell are located is connected in parallel with the series branch where the third battery cell and the fourth battery cell are located during the discharging state.

[0056] It should be noted that although the number of battery cells provided in this application is 4, in actual application, the number of battery cells is not limited and can also be other numbers such as 6 or 8. Only need to appropriately increase the MOS transistors to establish the connection relationship of each battery cell, and finally achieve that each battery cell is connected in series in pairs to form a branch during charging and the branches are connected in parallel with each other during discharging.

[0057] Compared with the prior art that directly connects each battery cell in series and then switches each battery cell to a parallel connection form in turn by the conduction and cut-off of a switching tube, in this application, the battery cells are connected in parallel in pairs at the beginning, and then the connection mode of the battery cells is adjusted by a switching tube. Even during parallel discharge, they are connected in parallel in pairs, greatly improving the charge and discharge capacity of the battery.

[0058] Figure 3 This is a schematic diagram of the connection of battery cells provided by this application. The figure includes four battery cells, namely Cell1, Cell2, Cell3, and Cell4. During charging, Cell1, Cell2, Cell3, and Cell4 are connected in series. During discharge, the branch where Cell1 and Cell2 are connected is connected in parallel with the branch where Cell3 and Cell4 are connected in series. At this time, Cell1 and Cell2 are connected in series, and Cell3 and Cell4 are connected in series.

[0059] In the charging state, connecting each battery cell in series can reduce the charging current. In the discharging state, connecting each battery cell in parallel can increase the discharge rate. In this way, by flexibly switching the series-parallel connection mode according to the charge and discharge states, both the fast charging requirement and the high-power discharging requirement can be met.

[0060] As an optional embodiment, the first switch group includes a third MOS transistor, a fourth MOS transistor, a fifth MOS transistor, a sixth MOS transistor, and a seventh MOS transistor. The gate of the third MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the third battery cell, and the source is connected to the negative electrode of the first battery cell. The gate of the fourth MOS transistor is connected to the status output pin of the control module, the drain is connected to the positive electrode of the fourth battery cell, and the source is connected to the positive electrode of the second battery cell. The gate of the fifth MOS transistor is connected to the status output pin of the control module, the drain is connected to the first voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through a first voltage acquisition device. The gate of the sixth MOS transistor is connected to the status output pin of the control module, the drain is connected to the second voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through a first voltage acquisition device. The gate of the seventh MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the fourth battery cell, and the source is connected to the positive electrode of the first battery cell.

[0061] The gates of the third MOS transistor, the fourth MOS transistor, the fifth MOS transistor, the sixth MOS transistor, and the seventh MOS transistor in the first switch group are all connected to the status output pin of the control module, and each MOS transistor conducts and cuts off according to the level signal output by the control module.

[0062] The control module is provided with voltage acquisition pins corresponding to each battery cell. Therefore, the number of voltage acquisition pins is the same as the number of battery cells, and each voltage acquisition pin is connected to a voltage acquisition device and a battery cell.

[0063] As an alternative embodiment, the second switch group includes a third switch group, an eighth MOS transistor, and a ninth MOS transistor. The third switch group is respectively connected to the output terminal of the inverter, the negative electrode of the third battery cell, and the positive electrode of the second battery cell. The gate of the eighth MOS transistor is connected to the status output pin of the control module, the source is connected to the first voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the third battery cell through a second voltage acquisition device. The gate of the ninth MOS transistor is connected to the status output pin of the control module, the source is connected to the second voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the fourth battery cell through a third voltage acquisition device.

[0064] The third switch group is a connection of two N-type MOS transistors. The input end of the third switch group is connected to the output terminal of the inverter, and is used to conduct and cut off according to the level signal output by the inverter, conduct when the inverter outputs a high-level signal, and cut off when the inverter outputs a low-level signal.

[0065] Both the eighth MOS transistor and the ninth MOS transistor are P-type MOS transistors. The gates of the eighth MOS transistor and the ninth MOS transistor are both connected to the status output pin of the control module, and each MOS transistor conducts and cuts off according to the level signal output by the control module.

[0066] Figure 4 This is a schematic diagram of the circuit in the charging state provided by this application. As shown in the figure, in the charging state, U1 outputs a high level to the inverter. At this time, each MOS transistor (Q1, Q2, Q4, Q6, Q8) of the first switch group is cut off, each MOS transistor (Q3, Q5, Q7) of the second switch group is conducted, and Q9 in the inverter is also disconnected. At this time, each battery cell is connected in series.

[0067] Figure 5 This is a schematic diagram of the circuit in the discharging state provided by this application. As shown in the figure, in the discharging state, U1 outputs a low level to the inverter. At this time, each MOS transistor (Q1, Q2, Q4, Q6, Q8) of the first switch group is conducted, each MOS transistor (Q3, Q5, Q7) of the second switch group is cut off, and Q10 in the inverter is also cut off. At this time, the battery cells are connected in parallel in pairs.

[0068] As an alternative embodiment, the circuit further includes a first resistor, and the first resistor is connected to the control module. The control module is used to judge the charge and discharge state of the battery according to the voltage drop across the first resistor.

[0069] When the battery is charging, the current usually flows from the power supply to the battery. Therefore, the voltage drop across the first resistor will have a specific polarity (for example, the positive pole is at one end of the resistor). The control module can detect the polarity of this voltage drop to judge whether the battery is charging.

[0070] When the battery is discharging, the current flows from the battery to the load. Therefore, the polarity of the voltage drop across the first resistor will be reversed, and the control module can determine whether the battery is discharging by detecting the polarity of the voltage drop.

[0071] In addition, in addition to the polarity of the voltage drop, the control module can also measure the magnitude of the voltage drop (i.e., the voltage value) to estimate the magnitude and direction of the current.

[0072] As an alternative embodiment, the circuit further includes a second resistor. One end of the second resistor is respectively connected to the gates of the fifth MOS transistor, the sixth MOS transistor of the first switch group, and the gate of the ninth MOS transistor of the second switch group. The second resistor is used to reduce the oscillation when the fifth MOS transistor, the sixth MOS transistor, and the ninth MOS transistor switch between conduction and cutoff.

[0073] The second resistor acts as a driving resistor and functions as a damping element in the circuit. When the MOS transistor switches rapidly between the on and off states, the driving resistor can consume part of the energy, thereby reducing the oscillation in the circuit, helping to stabilize the operating state of the MOS transistor, and preventing voltage or current mutations caused by rapid switching.

[0074] Reducing oscillation not only helps to protect the MOS transistor itself but also improves the reliability of the entire circuit. Oscillation may cause unnecessary energy loss, electromagnetic interference, and even component damage. By introducing the second resistor to reduce oscillation in this application, the service life of the circuit can be extended and the maintenance cost can be reduced.

[0075] As an alternative embodiment, the circuit further includes a protection device. The protection device is respectively connected to the control module and the load and is used to prevent reverse current from flowing to the load.

[0076] The protection device includes two MOS transistors. The gate of one MOS transistor is connected to the charging output pin of the control module, and the gate of the other MOS transistor is connected to the discharging output pin.

[0077] Exemplarily, when the battery is in the charging state, the charging output pin outputs a high level, and the MOS transistor connected to the charging output pin will conduct. At this time, the charging current is allowed to flow from the charging source to the battery. At the same time, the discharging output pin outputs a low level (or high impedance state), and the MOS transistor connected to the discharging output pin will be cutoff.

[0078] Exemplarily, when the battery is in the discharging state, when the discharging output pin outputs a high level, the MOS transistor connected to the discharging output pin will conduct. At this time, the current in the battery is allowed to flow to the load. At the same time, the charging output pin outputs a low level (or high impedance state), and the MOS transistor connected to the charging output pin will be cutoff, which ensures that during the discharging process, the charging source will not accidentally continue to charge the battery.

[0079] By setting up a protection device, it can be ensured that in abnormal situations (such as overcharging, over-discharging, short circuit, etc.), the two MOS transistors can be turned off in time to protect the battery and the circuit from damage.

[0080] This application provides a series-parallel switching circuit for battery charging and discharging, including: a control module, an inverter, a switching switch group, and multiple battery cells. The control module is connected to the inverter and the switching switch group, the inverter is connected to the switching switch group, the switching switch group is connected to the multiple battery cells, and the multiple battery cells are connected to the control module. The control module is used to output a level signal to the inverter according to the charging and discharging states. The inverter is used to receive the level signal and invert the level signal. The switching switch group is used to control the multiple battery cells to be in series during the charging state and in parallel during the discharging state according to the output of the inverter and the level signal output by the control module. By switching the series-parallel states of each battery cell according to the charging and discharging states of the battery, series charging can reduce the charging current, and parallel discharging can increase the discharge rate, solving the problem that the fixed series-parallel method of battery cells cannot meet both the fast charging requirement and the high-power discharging requirement of the battery.

[0081] According to another aspect of the embodiments of the present application, the present application also provides an electronic device, and the electronic device includes the above-mentioned series-parallel switching circuit for battery charging and discharging.

[0082] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying importance; the terms "bottom surface" and "top surface", "inner" and "outer" respectively refer to the geometric directions towards or away from a specific component.

[0083] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the connection inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations. In addition, in the description of the present application, unless otherwise stated, the meaning of "multiple" is two or more.

[0084] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A series-parallel switching circuit for battery charging and discharging, characterized in that, Comprising: A control module, an inverter, a switching switch group, and a plurality of battery cells. The control module is connected to the inverter and the switching switch group. The inverter is connected to the switching switch group. The switching switch group is connected to the plurality of battery cells. The plurality of battery cells are connected to the control module. The control module is configured to output a level signal to the inverter according to the charge and discharge states. The inverter is configured to receive the level signal and invert the level signal. The switching switch group is configured to control the plurality of battery cells to be connected in series in the charging state and in parallel in the discharging state according to the output of the inverter and the level signal output by the control module.

2. The circuit according to claim 1, characterized in that, The control module is configured to output a low level signal to the inverter through the status output pin when the battery is in the charging state, and output a high level signal to the inverter through the status output pin when the battery is in the discharging state.

3. The circuit according to claim 1, wherein The circuit further includes a plurality of voltage acquisition devices. One end of each voltage acquisition device is connected to the positive electrode of each battery cell in the plurality of battery cells, and the other end of each voltage acquisition device is respectively connected to each voltage acquisition pin of the control module. The voltage acquisition device is configured to acquire the voltage of the battery cell and transmit the voltage to the control module.

4. The circuit according to claim 2, wherein The inverter includes a first MOS transistor and a second MOS transistor. The gates of the first MOS transistor and the second MOS transistor are both connected to the status output pin of the control module. The first MOS transistor is configured to turn off when receiving the low level signal transmitted by the control module, and is further configured to turn on when receiving the high level signal transmitted by the control module and output an inverted low level signal through the source electrode. The second MOS transistor is configured to turn on when receiving the low level signal transmitted by the control module and output an inverted high level signal through the drain electrode, and is further configured to turn off when receiving the high level signal transmitted by the control module.

5. The circuit according to claim 4, wherein The switching switch group includes a first switch group and a second switch group. The first switch group is connected to the control module and the plurality of battery cells. The second switch group is connected to the control module, the inverter, and the plurality of battery cells. Each MOS transistor of the first switch group turns off when the control module outputs a low level signal and turns on when the control module outputs the high level signal. Each MOS transistor of the second switch group turns on when the control module outputs the low level signal and turns off when the control module outputs the high level signal.

6. The circuit according to claim 5, characterized in that, The plurality of battery cells include a first battery cell, a second battery cell, a third battery cell, and a fourth battery cell. The first battery cell, the second battery cell, the third battery cell, and the fourth battery cell are sequentially connected in series in the charging state, and the series branch where the first battery cell and the second battery cell are located is connected in parallel with the series branch where the third battery cell and the fourth battery cell are located in the discharging state.

7. The circuit according to claim 6, characterized in that, The first switch group includes a third MOS transistor, a fourth MOS transistor, a fifth MOS transistor, a sixth MOS transistor, and a seventh MOS transistor. The gate of the third MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the third battery cell, and the source is connected to the negative electrode of the first battery cell. The gate of the fourth MOS transistor is connected to the status output pin of the control module, the drain is connected to the positive electrode of the fourth battery cell, and the source is connected to the positive electrode of the second battery cell. The gate of the fifth MOS transistor is connected to the status output pin of the control module, the drain is connected to the first voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through a first voltage acquisition device. The gate of the sixth MOS transistor is connected to the status output pin of the control module, the drain is connected to the second voltage acquisition pin of the control module, and the source is connected to the positive electrode of the second battery cell through the first voltage acquisition device. The gate of the seventh MOS transistor is connected to the status output pin of the control module, the drain is connected to the negative electrode of the fourth battery cell, and the source is connected to the positive electrode of the first battery cell.

8. The circuit according to claim 7, wherein The second switch group includes a third switch group, an eighth MOS transistor, and a ninth MOS transistor. The third switch group is respectively connected to the output end of the inverter, the negative electrode of the third battery cell, and the positive electrode of the second battery cell. The gate of the eighth MOS transistor is connected to the status output pin of the control module, the source is connected to the first voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the third battery cell through a second voltage acquisition device. The gate of the ninth MOS transistor is connected to the status output pin of the control module, the source is connected to the second voltage acquisition pin of the control module, and the drain is connected to the positive electrode of the fourth battery cell through a third voltage acquisition device.

9. The circuit according to claim 1, wherein The circuit further includes a first resistor, which is connected to the control module, and the control module is used to judge the charge and discharge status of the battery according to the voltage drop across the first resistor.

10. The circuit according to claim 5, wherein The circuit further includes a second resistor, one end of which is respectively connected to the gates of the fifth MOS transistor, the sixth MOS transistor of the first switch group, and the gate of the ninth MOS transistor of the second switch group. The second resistor is used to reduce the oscillation when the fifth MOS transistor, the sixth MOS transistor, and the ninth MOS transistor switch between conduction and cut-off.

11. The circuit according to claim 1, characterized in that, The circuit further includes a protection device, which is respectively connected to the control module and the load, and is used to prevent reverse current from flowing to the load.

12. An electronic device, characterized in that, The electronic device includes the series-parallel switching circuit for battery charge and discharge according to any one of claims 1 to 11.

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