Battery protection circuit, control method and electronic device

Abstract

The embodiment of the application provides a battery protection circuit, a control method and electronic equipment, and belongs to the technical field of batteries. The battery protection circuit comprises a battery cell, a processor, a first control switch, a second control switch, a connector, a first diode and a second diode. The battery cell, the first control switch, the second control switch and the connector are connected in series. The processor is electrically connected with the first control switch, the second control switch, the connector and the battery cell. The first diode is connected in parallel with the first control switch. The second diode is connected in parallel with the second control switch. The connector is used for connecting with an external power supply. The battery protection circuit has a first working state and a second working state. When the battery protection circuit is in the first working state, the processor controls at least one of the first control switch and the second control switch to be in an open state or a half-conduction state, and the second diode is turned on.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery protection circuit, control method, and electronic device. Background Technology

[0002] With the development of technology, electronic devices are being used more and more widely. Typically, electronic devices contain batteries, and after long-term storage, the batteries need to be activated for the device to function properly.

[0003] In related technologies, electronic devices contain batteries, which typically include battery protection circuits. These circuits contain components such as battery cells and control switches. To prevent irreversible chemical changes from occurring inside the battery cell after it has discharged to 0V, which could affect its stability or even cause it to explode, a charging prohibition voltage is usually set for the battery cell. When the battery voltage falls below this prohibition voltage, the power management module connected to the battery protection circuit in the electronic device will prevent charging of the battery cell.

[0004] To extend the battery's lifespan, the prohibited charging voltage is typically set low. However, for reliable battery activation, the battery cell must not be over-discharged to the prohibited charging voltage; it must only be over-discharged to the minimum operating voltage of the processor in the battery cell's protection circuit. Generally, the processor's minimum operating voltage is higher than the battery cell's prohibited charging voltage, effectively increasing the minimum over-discharge voltage of the battery cell. This shortens the battery's lifespan and, more importantly, may cause problems with proper battery cell activation during reactivation. Summary of the Invention

[0005] This application provides a battery protection circuit to solve the problem of ineffective battery activation in related technologies.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows:

[0007] In a first aspect, embodiments of this application provide a battery protection circuit, including: a battery cell, a processor, a first control switch, a second control switch, a connector, a first diode, and a second diode;

[0008] The battery cell, the first control switch, the second control switch, and the connector are connected in series. The processor is electrically connected to the first control switch, the second control switch, the connector, and the battery cell. The first diode is connected in parallel with the first control switch, and the second diode is connected in parallel with the second control switch. The connector is used to connect to an external power source.

[0009] The battery protection circuit has a first operating state and a second operating state. When the battery protection circuit is in the first operating state, the processor controls at least one of the first control switch and the second control switch to be in an off state or a semi-conducting state, and the second diode is turned on. When the battery protection circuit is in the second operating state, the processor controls both the first control switch and the second control switch to be in a conducting state.

[0010] Secondly, embodiments of this application provide a control method applied to the battery protection circuit described in the first aspect above, the control method comprising:

[0011] When the battery protection circuit is in the first working state, at least one of the first control switch and the second control switch is controlled to be in the off state, and the second diode is turned on.

[0012] When the battery protection circuit is in the second operating state, both the first control switch and the second control switch are in the on state.

[0013] Thirdly, embodiments of this application provide an electronic device, which includes the battery protection circuit described in the first aspect above.

[0014] In this embodiment, since the battery cell, first control switch, second control switch, and connector are connected in series, and the first diode and first control switch are connected in parallel, and the second diode and second control switch are connected in parallel, after the connector is connected to an external power source, the external power source can charge the battery cell through the first control switch, second control switch, first diode, and second diode, enabling the battery cell to have electrical energy. Then, the states of the first and second control switches can be changed, activating the battery cell. Specifically, when the battery protection circuit is in the first operating state, the processor controls at least one of the first and second control switches to be in the off state, and the second diode is turned on. Therefore, the external power source can transfer electrical energy to the connector, and the connector can then transfer electrical energy to the battery cell through the second diode and first control switch, causing a change in the battery cell's voltage. When the battery protection circuit is in the second operating state, the processor controls both the first and second control switches to be in the on state. At this time, the battery cell can discharge externally through the first and second control switches, thereby activating the battery cell. In other words, in this embodiment, by setting a processor that is electrically connected to both a first control switch and a second control switch, the second diode is turned on when the battery cell is being charged, and at least one of the first and second control switches is in an off state. Therefore, current flows through the second diode, and when current flows through the second diode, there is a voltage drop in the second diode. Thus, the battery can be activated when the voltage of the battery cell is lower than the voltage drop of the second diode than the minimum operating voltage of the processor. It is not necessary to raise the minimum over-discharge voltage of the battery cell to the minimum operating voltage of the processor. This means that the increase in the minimum over-discharge voltage of the battery cell is smaller, which can increase the storage time of the electronic device. Furthermore, the smaller increase in the minimum over-discharge voltage of the battery cell ensures that the battery cell can be activated normally when activating the battery, thus providing a certain degree of protection for the battery cell. Attached Figure Description

[0015] Figure 1 This diagram illustrates one embodiment of a battery protection circuit provided in this application.

[0016] Figure 2 This is a second schematic diagram illustrating a battery protection circuit provided in an embodiment of this application;

[0017] Figure 3 This is a third schematic diagram illustrating a battery protection circuit provided in an embodiment of this application;

[0018] Figure 4 A flowchart illustrating a control method provided in an embodiment of this application;

[0019] Figure 5 This is a schematic diagram illustrating one embodiment of an electronic device provided in this application;

[0020] Figure 6 This is a second schematic diagram illustrating an electronic device provided in an embodiment of this application;

[0021] Figure 7 This is a third schematic diagram illustrating an electronic device provided in an embodiment of this application.

[0022] Figure label:

[0023] 10: Battery cell; 20: Processor; 30: First control switch; 40: Second control switch; 50: Connector; 60: First diode; 70: Second diode; 80: Differential amplifier circuit; 81: First resistor; 82: Second resistor; 83: Third resistor; 84: Fourth resistor; 85: Amplifier. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0026] Reference Figure 1 The diagram shows one of the schematic diagrams of a battery protection circuit provided in an embodiment of this application; see reference. Figure 2 The diagram below shows a second schematic of a battery protection circuit provided in an embodiment of this application; see reference to... Figure 3 The diagram below shows a third schematic representation of a battery protection circuit provided in an embodiment of this application. Figures 1 to 3 As shown, the battery protection circuit includes: a battery cell 10, a processor 20, a first control switch 30, a second control switch 40, a connector 50, a first diode 60, and a second diode 70.

[0027] Battery cell 10, first control switch 30, second control switch 40, and connector 50 are connected in series. Processor 20 is electrically connected to first control switch 30, second control switch 40, connector 50, and battery cell 10. First diode 60 is connected in parallel with first control switch 30, and second diode 70 is connected in parallel with second control switch 40. Connector 50 is used to connect to an external power source. The battery protection circuit has a first operating state and a second operating state. When the battery protection circuit is in the first operating state, processor 20 controls at least one of first control switch 30 and second control switch 40 to be in an off state or a semi-conducting state, and second diode 70 is turned on. When the battery protection circuit is in the second operating state, processor 20 controls both first control switch 30 and second control switch 40 to be in a conducting state.

[0028] In this embodiment, since the battery cell 10, the first control switch 30, the second control switch 40, and the connector 50 are connected in series, and the first diode 60 is connected in parallel with the first control switch 30 and the second diode 70 is connected in parallel with the second control switch, after the connector 50 is connected to an external power source, the external power source can charge the battery cell 10 through the first control switch 30, the second control switch 40, the first diode 60, and the second diode 70, so that the battery cell 10 has electrical energy. Then, the states of the first control switch 30 and the second control switch 40 can be changed, so that the battery cell 10 is activated. Specifically, when the battery protection circuit is in the first operating state, the processor 20 controls at least one of the first control switch 30 and the second control switch 40 to be in the off state, and the second diode 70 is turned on. Therefore, the external power supply can transfer electrical energy to the connector 50, and then the connector 50 can transfer electrical energy to the battery cell 10 through the second diode 70 and the first control switch 30, causing the voltage of the battery cell 10 to change. When the battery protection circuit is in the second operating state, the processor 20 controls both the first control switch 30 and the second control switch 40 to be in the on state. At this time, the battery cell 10 can discharge to the outside through the first control switch 30 and the second control switch 40, thereby activating the battery cell 10. That is, in this embodiment, by setting up a processor 20, and the processor 20 being electrically connected to the first control switch 30 and the second control switch 40 respectively, when charging the battery cell 10, the second diode 70 is turned on, and at least one of the first control switch 30 and the second control switch 40 is in an off state. Therefore, it is equivalent to current flowing through the second diode 70. When current flows through the second diode 70, the second diode 70 will have a voltage drop. Thus, when the minimum over-discharge voltage of the battery cell 10 is lower than the minimum operating voltage of the processor 20, the battery can be activated. It is not necessary to increase the minimum over-discharge voltage of the battery cell 10 to the minimum operating voltage of the processor 20. This is equivalent to reducing the increase in the minimum over-discharge voltage of the battery cell 10, which can increase the storage time of the electronic device. Furthermore, the smaller increase in the minimum over-discharge voltage of the battery cell 10 can ensure that the battery cell 10 can be activated normally when activating the battery, thus providing a certain degree of protection for the battery cell 10.

[0029] It should be noted that, in this embodiment, the positive terminal of the battery cell 10 is electrically connected to the first terminal of the first control switch 30, the second terminal of the first control switch 30 is electrically connected to the first terminal of the second control switch 40, and the second terminal of the second control switch 40 is electrically connected to the connector 50. The processor 20 may include a first pin, a first control pin, a second control pin, and a voltage pin. The first pin is electrically connected to the battery cell 10, the first control pin is electrically connected to the control terminal of the first control switch 30, the second control pin is electrically connected to the control terminal of the second control switch 40, and the voltage pin is electrically connected to the connector 50. The two ends of the first diode 60 are respectively electrically connected to the first and second terminals of the first control switch 30, and the two ends of the second diode 70 are respectively electrically connected to the first and second terminals of the second control switch 40. The connector 50 is used to electrically connect to the power management chip on the motherboard of the electronic device. When the electronic device is charged via a charging cable, electrical energy is transferred to the connector 50 through the power management chip, and then the connector 50 charges the battery cell 10.

[0030] For example, such as Figure 1 As shown, the first pin can be the VC pin, the first control pin can be the CHG pin, the second control pin can be the DSG pin, and the voltage pin can be the PACK pin.

[0031] It should also be noted that, in the embodiments of this application, both the first control switch 30 and the second control switch 40 can be MOSFETs.

[0032] Furthermore, in this embodiment, the processor 20 is connected to the battery cell 10. Therefore, the processor 20 can collect the battery cell voltage of the battery cell 10, thereby determining the relationship between the battery cell voltage and the processor 20's own operating voltage. When the battery cell voltage is less than the processor's operating voltage, the battery protection circuit is in a first operating state. When the battery cell voltage is greater than or equal to the processor's operating voltage, the battery protection circuit is in a second operating state.

[0033] In addition, in some embodiments, the processor 20 is also used to: control the first control switch 30 and the second control switch 40 to be in the on state when the cell voltage is greater than or equal to the operating voltage of the processor 20, so that the cell 10 supplies power to the outside through the first control switch 30 and the second control switch 40, and the battery is activated.

[0034] In some embodiments, the processor 20 is further configured to: control the first control switch 30 to be in a conducting state and control the second control switch 40 to be in a de-conducting state when the cell voltage is lower than the operating voltage of the processor 20, so that the current flowing into the connector 50 passes through the second diode 70 and the first control switch 30 to charge the cell 10; and acquire the charging cell voltage of the cell 10 after charging, and control both the first control switch 30 and the second control switch 40 to be in a conducting state when the charging cell voltage is higher than the operating voltage of the processor 20, so as to activate the battery.

[0035] In some embodiments, the processor 20 is also configured to: control the first control switch 30 to be in a semi-conducting state and the second control switch 40 to be in a conducting state when the cell voltage is lower than the operating voltage of the processor 20, so that the current flowing into the connector 50 flows through the second control switch 40 and the first control switch 30 to charge the cell 10; and acquire the charging cell voltage of the cell 10 after charging, and control both the first control switch 30 and the second control switch 40 to be in a conducting state when the charging cell voltage is higher than the operating voltage of the processor 20, so that the battery is activated.

[0036] In addition, in some embodiments, the processor 20 also uses: to obtain the voltage difference between the voltages at both ends of the first control switch 30; and to obtain the charging cell voltage of the battery cell 10 after charging when the voltage difference is greater than a preset threshold, wherein the preset threshold is the difference between the operating voltage of the processor 20 and the cell voltage of the battery cell 10.

[0037] In addition, in some embodiments, the processor 20 is also configured to: adjust the impedance of the first control switch 30 when the voltage difference is less than a preset threshold, so as to adjust the voltage difference between the voltages at both ends of the first control switch 30 so that the voltage difference is greater than the preset threshold.

[0038] In addition, in some embodiments, the processor 20 is further configured to: adjust the input voltage to the first control switch 30 according to the relationship between the impedance of the first control switch 30 and the input voltage, so as to adjust the impedance of the first control switch 30.

[0039] Additionally, in some embodiments, such as Figure 2As shown, the battery protection circuit may further include a differential amplifier circuit 80, which includes a first resistor 81, a second resistor 82, a third resistor 83, a fourth resistor 84, and an amplifier 85. The first terminal of the first resistor 81 is electrically connected to the first terminal of the first control switch 30; the first terminal of the second resistor 82 is electrically connected to the second terminal of the first control switch 30; the second terminals of both the first and third resistors 83 are electrically connected to the first terminal of the amplifier 85; the second terminals of both the second and fourth resistors 84 are electrically connected to the second terminal of the amplifier 85; the second terminal of the third resistor 83 is electrically connected to the third terminal of the amplifier 85; the third terminal of the amplifier 85 is electrically connected to the processor 20; and the second terminal of the fourth resistor 84 is grounded.

[0040] In addition, in this embodiment of the application, the processor 20 is also used to: obtain the input value of the third terminal of the amplifier 85, wherein the input value represents the voltage difference between the voltages at the two terminals of the first control switch 30.

[0041] In addition, in this embodiment, the battery protection circuit may include a second protection circuit, which includes a third control switch, a fourth control switch, a third diode, and a fourth diode. The first terminal of the third control switch is electrically connected to the battery cell 10, the second terminal of the third control switch is electrically connected to the first terminal of the fourth control switch, and the second terminal of the fourth control switch is electrically connected to the connector 50. The two terminals of the third diode are electrically connected to the two terminals of the third control switch, and the two terminals of the fourth diode are electrically connected to the two terminals of the fourth control switch. The second protection circuit can protect the battery cell 10 in the event of failure of the first control switch 30 or the second control switch 40.

[0042] In this embodiment, since the battery cell 10, the first control switch 30, the second control switch 40, and the connector 50 are connected in series, and the first diode 60 is connected in parallel with the first control switch 30 and the second diode 70 is connected in parallel with the second control switch, after the connector 50 is connected to an external power source, the external power source can charge the battery cell 10 through the first control switch 30, the second control switch 40, the first diode 60, and the second diode 70, so that the battery cell 10 has electrical energy. Then, the states of the first control switch 30 and the second control switch 40 can be changed, so that the battery cell 10 is activated. Specifically, when the battery protection circuit is in the first operating state, the processor 20 controls at least one of the first control switch 30 and the second control switch 40 to be in the off state, and the second diode 70 is turned on. Therefore, the external power supply can transfer electrical energy to the connector 50, and then the connector 50 can transfer electrical energy to the battery cell 10 through the second diode 70 and the first control switch 30, causing the voltage of the battery cell 10 to change. When the battery protection circuit is in the second operating state, the processor 20 controls both the first control switch 30 and the second control switch 40 to be in the on state. At this time, the battery cell 10 can discharge to the outside through the first control switch 30 and the second control switch 40, thereby activating the battery cell 10. That is, in this embodiment, by setting up a processor 20, and the processor 20 being electrically connected to the first control switch 30 and the second control switch 40 respectively, when charging the battery cell 10, the second diode 70 is turned on, and at least one of the first control switch 30 and the second control switch 40 is in an off state. Therefore, it is equivalent to current flowing through the second diode 70. When current flows through the second diode 70, the second diode 70 will have a voltage drop. Thus, when the minimum over-discharge voltage of the battery cell 10 is lower than the minimum operating voltage of the processor 20, the battery can be activated. It is not necessary to increase the minimum over-discharge voltage of the battery cell 10 to the minimum operating voltage of the processor 20. This is equivalent to reducing the increase in the minimum over-discharge voltage of the battery cell 10, which can increase the storage time of the electronic device. Furthermore, the smaller increase in the minimum over-discharge voltage of the battery cell 10 can ensure that the battery cell 10 can be activated normally when activating the battery, thus providing a certain degree of protection for the battery cell 10.

[0043] Reference Figure 4 The diagram illustrates a flowchart of a control method provided in an embodiment of this application. This control method is applied to a battery protection circuit in any of the above embodiments; specifically, the control method is applied to a processor in the battery protection circuit. Figure 4 As shown, the control method includes:

[0044] Step 401: When the battery protection circuit is in the first working state, control at least one of the first control switch and the second control switch to be in the off state or semi-conducting state, and turn on the second diode.

[0045] In this embodiment, the processor 20 is connected to the battery cell 10. Therefore, when the connector is connected to an external power source, the processor 20 can acquire the battery cell voltage of the battery cell 10. Specifically, after a charging cable is inserted into the electronic device, the charging cable can transfer the power from the external power source to the power management chip on the motherboard of the electronic device. The power management chip can then transfer the power to the connector 50, which will then connect to the external power source and provide voltage to the processor 20, enabling the processor 20 to operate. The voltage provided by the connector 50 to the processor 20 must be greater than the operating voltage of the processor 20. For example, if the voltage provided by the connector 50 to the processor 20 is V1, and the operating voltage of the processor 20 is V2, V1 must be greater than V2 for the processor 20 to operate. Once the processor 20 is operating, it can acquire the battery cell voltage of the battery cell 10 through the first pin, i.e., through the VC pin. Since the battery cell 10 itself has a certain voltage, and the processor 20 is electrically connected to the battery cell 10, the processor 20 can acquire the battery cell voltage of the battery cell 10.

[0046] After acquiring the cell voltage of battery cell 10, processor 20 can determine its own operating voltage. Based on the cell voltage and operating voltage, it can control the states of the first control switch 30 and the second control switch 40, i.e., control the on or off states of the first control switch 30 and the second control switch 40. When the states of the first control switch 30 and the second control switch 40 change, electrical energy can be transferred to the battery, thereby activating the battery.

[0047] Specifically, the processor 20 can determine the magnitude between the cell voltage and the processor 20's own operating voltage. Therefore, before step 401, the control method may further include: acquiring the cell voltage of the cell and determining the processor's operating voltage.

[0048] It should be noted that, in this embodiment, the battery protection circuit is in a first operating state when the cell voltage is lower than the processor's operating voltage. When the cell voltage is greater than or equal to the processor's operating voltage, the battery protection circuit is in a second operating state. Therefore, when the battery protection circuit is in the first operating state, at least one of the first and second control switches can be controlled to be in an open state, and the second diode can be turned on.

[0049] In some implementations, step 401 can be implemented as follows: when the cell voltage is lower than the processor's operating voltage, the first control switch is controlled to be in the ON state and the second control switch is controlled to be in the OFF state, so that the current flowing into the connector passes through the second diode and the first control switch to charge the cell. The charging cell voltage is then obtained. When the charging cell voltage is higher than the processor's operating voltage, both the first and second control switches are controlled to be in the ON state to activate the battery.

[0050] When the cell voltage is lower than the processor 20's operating voltage, the processor 20 controls the first control switch 30 to turn on and the second control switch 40 to turn off. This allows the charging current flowing through the connector 50 to pass through the second diode 70, then into the first control switch 30, and finally into the cell 10 to charge it. While the cell 10 is charging, the processor 20 can monitor its voltage in real time. When the current voltage of the cell 10 is greater than the processor 20's operating voltage, the processor 20 will control both the first control switch 30 and the second control switch 40 to be on, thus activating the battery.

[0051] Furthermore, in related technologies, after a battery is installed in an electronic device, due to its chemical properties, when the battery is discharged to 0V and then recharged, irreversible chemical changes occur inside the battery, affecting its stability and potentially causing an explosion. Therefore, most battery manufacturers set a prohibited charging voltage. When the battery voltage falls below this prohibited voltage, the protection IC on the battery's protection board shuts down the charge / discharge MOSFET, preventing further charging. Generally, within the battery's safety limits, the prohibited charging voltage is set as low as possible to extend the storage life of electronic devices.

[0052] In addition, in related technologies, if the following are adopted Figure 2The battery structure shown assumes that the voltage supplied by connector 50 to processor 20 is V1, the operating voltage of processor 20 is V2, and the prohibited charging voltage of battery cell 10 is V3. When battery cell 10 is over-discharged, i.e., when battery cell 10 is over-discharged and its voltage reaches V3, connector 50 needs to be connected to an external power source, meaning the electronic device needs to be plugged into a charging cable to activate the battery. After the electronic device is plugged into a charging cable, the power management chip on the motherboard of the electronic device provides an activation voltage to connector 50, which then provides voltage V1 to processor 20. Typically, V1 > V2 > V3. Under the action of V1, processor 20 will start running and simultaneously send commands to first control switch 30 and second control switch 40 through the first control pin and the second control pin, i.e., through pin CHG and pin DSG, respectively. This will then activate first control switch 30 and second control switch 40. However, since V1 is only the activation voltage and its driving capability is limited, after the first control switch 30 and the second control switch 40 are turned on, V1 will be reduced to V3, causing the voltage on the processor 20 to change from V3 to V1, which is lower than the operating voltage V2 of the processor 20. As a result, the processor 20 cannot maintain normal operation, causing the first control switch 30 and the second control switch 40 to be turned off, and the battery cannot be activated.

[0053] To reliably activate the battery, the battery cell 10 must not be over-discharged to the charging-restricted voltage V3, and must be at least over-discharged to the processor 20's operating voltage V2, i.e., V3 = V2. At this point, after the first control switch 30 and the second control switch 40 are turned on, the processor 20's voltage is pulled from V1 to V2, meaning the processor 20's voltage is equal to its own operating voltage, thus allowing the fuel gauge to continue operating. However, increasing the charging-restricted voltage of the battery cell 10 from V3 to V2 will shorten the electronic device's storage time.

[0054] In the embodiments of this application, such as Figure 2As shown, when the cell voltage is lower than the operating voltage of the processor 20, the first control switch 30 is in the ON state and the second control switch 40 is in the OFF state. The current flowing into the connector 50, i.e., the charging current, flows into the second diode 70, then through the first control switch 30, and finally into the cell 10. Assuming the voltage drop across the second diode 70 is Vd2, then V1 = Vcell + Vd2, where Vcell is the voltage across the cell 10. This is because after the first control switch 30 is ON, it acts like a wire, and the second diode 70 has a voltage drop. This means that V1 will drop to Vd2 through the second diode 70, and then be transmitted to the cell 10, thus making V1 = Vcell + Vd2. Since the condition for processor 20 to operate normally is V1≥V2, therefore Vcell≥V2-Vd2. This means that the cell voltage only needs to be within Vd2 lower than the normal operating voltage V2 of processor 20 for processor 20 to operate normally. In other words, the prohibited charging voltage of cell 10 can be made Vd2 lower than the normal operating voltage V2 of processor 20 to enable processor 20 to operate normally, thereby activating the battery. Compared to related technologies where the prohibited charging voltage of cell 10 is equal to the normal operating voltage of processor 20 (V3=V2), in this embodiment, by controlling the states of the first control switch 30 and the second control switch 40 by processor 20, the prohibited charging voltage of cell 10 can be made Vd2 lower than the normal operating voltage of processor 20. This effectively reduces the prohibited charging and discharging voltage of the battery, increasing the storage time of the electronic device after the battery is applied.

[0055] In some implementations, step 401 can also be implemented as follows: when the cell voltage is lower than the processor's operating voltage, the first control switch is controlled to be in a semi-conducting state and the second control switch is controlled to be in a conducting state, so that the current flowing into the connector flows through the second control switch and the first control switch to charge the cell; the charging cell voltage after charging is obtained; when the charging cell voltage is higher than the processor's operating voltage, both the first control switch and the second control switch are controlled to be in a conducting state.

[0056] When the cell voltage is lower than the operating voltage of the processor 20, the processor 20 controls the first control switch 30 to be in a semi-conducting state and the second control switch 40 to be in a conducting state. At this time, the current flowing into the connector 50 will first flow into the second control switch 40, then into the first control switch 30, and finally into the cell 10 to charge the cell 10. After the current flows into the cell 10, the voltage of the cell 10 will change. The processor 20 can obtain the charging cell voltage of the cell 10 in real time and compare the charging cell voltage with the operating voltage of the processor 20. When the charging cell voltage is greater than the operating voltage of the processor 20, the processor 20 can control the first control switch 30 and the second control switch 40 to be in a conducting state. At this time, the battery's electrical energy can be transferred to the outside through the first control switch 30 and the second control switch 40, thereby activating the battery.

[0057] It should be noted that by setting the first diode 60, when current flows into the first diode 60, the current can only flow from the first control switch 30 to the second control switch 40. Due to the characteristics of the diode, the current cannot flow from the second control switch 40 to the first control switch 30 within the first diode 60. Similarly, by setting the second diode 70, when current flows into the second diode 70, the current can only flow from the second control switch 40 to the first control switch 30. Again, due to the characteristics of the diode, the current cannot flow from the first control switch 30 to the second control switch 40 within the second diode 70. Therefore, only when both the first control switch 30 and the second control switch 40 are turned on can the battery current flow through both switches to the outside, thus activating the battery.

[0058] In addition, in some implementations, before obtaining the charging cell voltage after charging, the control method may further include: obtaining the voltage difference between the voltages at both ends of the first control switch; if the voltage difference is greater than a preset threshold, obtaining the charging cell voltage after charging, wherein the preset threshold is the difference between the processor's operating voltage and the cell voltage.

[0059] Because the first control switch 30 is in a semi-conducting state, it has a large impedance. Therefore, after current flows through the first control switch 30, the voltage across it will differ; that is, the first control switch 30 will have a voltage drop due to its impedance, resulting in a voltage difference between its two ends. The processor 20 can obtain the voltage difference between the two ends of the first control switch 30. If the voltage difference exceeds a preset threshold, the processor 20 then obtains the charging cell voltage after charging. The processor 20 then compares the charging cell voltage with its operating voltage. If the charging cell voltage is greater than the processor 20's operating voltage, the processor 20 controls both the first control switch 30 and the second control switch 40 to be in a conducting state, thus activating the battery.

[0060] In addition, in related technologies, if the following are adopted Figure 2 The battery structure shown assumes that the voltage supplied by connector 50 to processor 20 is V1, the operating voltage of processor 20 is V2, and the prohibited charging voltage of battery cell 10 is V3. When battery cell 10 is over-discharged, i.e., when battery cell 10 is over-discharged and its voltage reaches V3, connector 50 needs to be connected to an external power source, meaning the electronic device needs to be plugged into a charging cable to activate the battery. After the electronic device is plugged into a charging cable, the power management chip on the motherboard of the electronic device provides an activation voltage to connector 50, which then provides voltage V1 to processor 20. Typically, V1 > V2 > V3. Under the action of V1, processor 20 will start running and simultaneously send commands to first control switch 30 and second control switch 40 through the first control pin and the second control pin, i.e., through pin CHG and pin DSG, respectively. This will then activate first control switch 30 and second control switch 40. However, since V1 is only the activation voltage and its driving capability is limited, after the first control switch 30 and the second control switch 40 are turned on, V1 will be reduced to V3, causing the voltage on the processor 20 to change from V3 to V1, which is lower than the operating voltage V2 of the processor 20. As a result, the processor 20 cannot maintain normal operation, causing the first control switch 30 and the second control switch 40 to be turned off, and the battery cannot be activated.

[0061] To reliably activate the battery, the battery cell 10 must not be over-discharged to the charging-restricted voltage V3, and must be at least over-discharged to the processor 20's operating voltage V2, i.e., V3 = V2. At this point, after the first control switch 30 and the second control switch 40 are turned on, the processor 20's voltage is pulled from V1 to V2, meaning the processor 20's voltage is equal to its own operating voltage, thus allowing the fuel gauge to continue operating. However, increasing the charging-restricted voltage of the battery cell 10 from V3 to V2 will shorten the electronic device's storage time.

[0062] In this embodiment, when the cell voltage is lower than the operating voltage of the processor 20, the first control switch 30 is in a semi-conducting state, and the second control switch 40 is in a conducting state. The current flowing into the connector 50, i.e., the charging current, flows into the second control switch 40, then into the first control switch 30, and then into the cell 10. When the first control switch 30 is in a semi-conducting state, there is a voltage difference across its terminals, i.e., a voltage drop across the first control switch 30. Assuming the voltage difference across the first control switch 30 is VQ1, then V1 = Vcell + VQ1, where Vcell is the voltage on the cell 10. This is because after the second control switch 40 is turned on, it acts like a wire, and the first control switch 30 has a voltage drop. This means that V1 will decrease to VQ1 after passing through the first control switch 30, and then be transmitted to the cell 10, thus making V1 = Vcell + VQ1. Since the condition for processor 20 to operate normally is V1≥V2, therefore Vcell+VQ1≥V2, i.e., Vcell≥V2-VQ1. This means that the processor 20 only needs to be within VQ1 lower than the normal operating voltage V2 of the processor 20 for it to operate normally. In other words, the prohibited charging voltage of the battery cell 10 can be made VQ1 lower than the normal operating voltage V2 of the processor 20 to enable normal operation of the processor 20 and thus activate the battery. Compared to related technologies where the prohibited charging voltage of the battery cell 10 is equal to the normal operating voltage of the processor 20 (V3=V2), in this embodiment, by controlling the states of the first control switch 30 and the second control switch 40, the prohibited charging voltage of the battery cell 10 can be made VQ1 lower than the normal operating voltage of the processor 20. This effectively reduces the prohibited charging and discharging voltage of the battery, increasing the storage time of the electronic device after the battery is applied.

[0063] In addition, since the normal working condition of processor 20 is V1≥V2, therefore Vcell+VQ1≥V2, that is, VQ1≥V2-Vcell. In other words, the voltage difference between the two ends of the first control switch 30 is greater than the difference between the working voltage of processor 20 and the cell voltage of battery cell 10. Processor 20 can obtain the charging cell voltage of battery cell 10 after charging, and then determine the magnitude of the charging cell voltage and the working voltage of processor 20. When the charging cell voltage is greater than the working voltage of processor 20, both the first control switch 30 and the second control switch 40 are controlled to be in the on state.

[0064] In addition, in some implementations, when the voltage difference is less than a preset threshold, the impedance of the first control switch is adjusted to adjust the voltage difference between the two ends of the first control switch so that the voltage difference is greater than the preset threshold.

[0065] When the voltage difference across the first control switch 30 is less than a preset threshold, the processor 20 can adjust the impedance of the first control switch 30. When the impedance of the first control switch 30 changes, the voltage drop across it will also change. That is, the first control switch 30 acts as a resistor; when the resistance changes but the current flowing through it remains constant, the voltage across the resistor will change. After adjusting the impedance of the first control switch 30, the processor 20 is essentially adjusting the voltage difference across the first control switch 30, ensuring that the voltage difference exceeds the preset threshold.

[0066] In some implementations, adjusting the impedance of the first control switch can be achieved by adjusting the input voltage to the first control switch according to the relationship between the impedance of the first control switch and the input voltage, thereby adjusting the impedance of the first control switch.

[0067] The correspondence between the blocking of the first control switch 30 and the input voltage of the first control switch 30 can be obtained in advance. Then, according to the relationship between the impedance of the first control switch 30 and the input voltage, the input voltage of the first control switch 30 is adjusted. After the input voltage of the first control switch 30 changes, the impedance of the first control switch 30 will change accordingly, thereby changing the voltage difference across the first control switch 30.

[0068] It should be noted that the first control switch 30 is a MOSFET. When the MOSFET is in a semi-conducting state, the impedance of the MOSFET will change when the input voltage to the MOSFET changes.

[0069] In some implementations, the battery may also include a differential amplifier circuit 80, which includes a first resistor 81, a second resistor 82, a third resistor 83, a fourth resistor 84, and an amplifier 85. The first terminal of the first resistor 81 is electrically connected to the first terminal of the first control switch 30; the first terminal of the second resistor 82 is electrically connected to the second terminal of the first control switch 30; the second terminals of both the first and third resistors 83 are electrically connected to the first terminal of the amplifier 85; the second terminals of both the second and fourth resistors 84 are electrically connected to the second terminal of the amplifier 85; the second terminal of the third resistor 83 is electrically connected to the third terminal of the amplifier 85; the third terminal of the amplifier 85 is electrically connected to the processor 20; and the second terminal of the fourth resistor 84 is grounded. In this case, obtaining the voltage difference between the two terminals of the first control switch 30 can be achieved by obtaining the input value at the third terminal of the amplifier, where the input value represents the voltage difference between the two terminals of the first control switch.

[0070] By setting up a differential amplifier circuit 80, which is connected to both ends of the first control switch 30, the differential amplifier circuit 80 can obtain the voltage across the two ends of the first control switch 30 and determine the voltage difference. Then, the differential amplifier circuit 80 can input the voltage difference to the processor 20 through the amplifier 85. The processor 20 can then obtain the input value at the third end of the amplifier 85, thereby obtaining the voltage difference between the two ends of the first control switch 30.

[0071] In some implementations, a first voltmeter may be electrically connected to the first terminal of the first control switch 30, and a second voltmeter may be electrically connected to the second terminal of the first control switch 30. Both the first and second voltmeters are electrically connected to the processor 20. Thus, the first voltmeter detects the voltage value at the first terminal of the first control switch 30, and the second voltmeter detects the voltage value at the second terminal of the first control switch 30. After the processor 20 obtains the voltage values ​​at the first and second terminals of the first control switch 30, the processor 20 can determine the voltage difference.

[0072] It should be noted that when the first control switch 30 is a MOSFET, the first terminal of the first control switch 30 is the source and the second terminal is the drain.

[0073] It should also be noted that, in this embodiment, the processor 20 can be a fuel gauge in the battery. The battery may include a housing, and the battery cell 10, the first control switch 30, the second control switch 40, the fuel gauge, the first diode 60, and the second diode 70 are all located in the housing, while the connector 50 is located on the housing.

[0074] Step 402: When the battery protection circuit is in the second working state, both the first control switch and the second control switch are turned on.

[0075] In some implementations, step 402 can be implemented as follows: when the cell voltage is greater than or equal to the processor's operating voltage, both the first control switch and the second control switch 40 are controlled to be in the on state, so that the cell supplies power to the outside through the first control switch and the second control switch, and the battery is activated.

[0076] After the processor 20 acquires the cell voltage of the battery cell 10, it compares the cell voltage with its own operating voltage. When the cell voltage is greater than or equal to the processor 20's operating voltage, the processor 20 controls both the first control switch 30 and the second control switch 40 to be turned on. At this time, electrical energy can be transferred to the battery through the first control switch 30 and the second control switch 40, and the battery can also supply power to the outside through the first control switch 30 and the second control switch 40, thus activating the battery. Here, "activated battery" means that the battery can supply power to the outside.

[0077] like Figures 5 to 7 As shown, this application provides an electronic device that includes the battery protection circuit found in any of the above embodiments.

[0078] The electronic device may also include a motherboard, on which a power management chip is provided, and the power management chip is electrically connected to the connector 50.

[0079] It should be noted that, in the embodiments of this application, electronic devices include, but are not limited to, mobile phones, tablets, laptops, handheld computers, vehicle terminals, wearable devices, and pedometers.

[0080] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0081] Although optional embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the optional embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0082] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity from another, and do not necessarily require or imply any such actual relationship or order between these entities. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or terminal device that includes that element.

[0083] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the principles and implementation methods of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A battery protection circuit, characterized in that, include: Battery cell, processor, first control switch, second control switch, connector, first diode, and second diode; The battery cell, the first control switch, the second control switch, and the connector are connected in series. The processor is electrically connected to the first control switch, the second control switch, the connector, and the battery cell. The first diode is connected in parallel with the first control switch, and the second diode is connected in parallel with the second control switch. The connector is used to connect to an external power source. The battery protection circuit has a first working state and a second working state. When the battery protection circuit is in the first working state, the processor controls at least one of the first control switch and the second control switch to be in an off state or a semi-conducting state, and the second diode is turned on. When the battery protection circuit is in the second working state, the processor controls both the first control switch and the second control switch to be in a conducting state. When the cell voltage is lower than the processor's operating voltage, the battery protection circuit is in its first operating state. When the cell voltage is greater than or equal to the processor's operating voltage, the battery protection circuit is in a second operating state; The processor controlling at least one of the first control switch and the second control switch to be in an off state or a semi-conducting state includes: controlling the first control switch to be in a conducting state and controlling the second control switch to be in an off state, wherein the connector is connected to the second diode and the first control switch; or controlling the first control switch to be in a semi-conducting state and the second control switch to be in a conducting state, wherein the connector is connected to the second control switch and the first control switch.

2. The battery protection circuit according to claim 1, characterized in that, The battery protection circuit further includes a differential amplifier circuit, which includes a first resistor, a second resistor, a third resistor, a fourth resistor, and an amplifier. The first end of the first resistor is electrically connected to the first end of the first control switch, the first end of the second resistor is electrically connected to the second end of the first control switch, the second end of the first resistor and the first end of the third resistor are both electrically connected to the first end of the amplifier, the second end of the second resistor and the first end of the fourth resistor are both electrically connected to the second end of the amplifier, the second end of the third resistor is electrically connected to the third end of the amplifier, the third end of the amplifier is electrically connected to the processor, and the second end of the fourth resistor is grounded.

3. A control method applied to the battery protection circuit according to any one of claims 1-2, characterized in that, The method includes: When the battery protection circuit is in the first working state, at least one of the first control switch and the second control switch is controlled to be in the off state, and the second diode is turned on. When the battery protection circuit is in the second operating state, both the first control switch and the second control switch are in the on state.

4. The control method according to claim 3, characterized in that, When the battery protection circuit is in a first operating state, before controlling at least one of the first control switch and the second control switch to be in an off state and before the second diode is turned on, the method further includes: The cell voltage of the battery cell is collected, and the operating voltage of the processor is determined.

5. The control method according to claim 4, characterized in that, When the battery protection circuit is in a first operating state, controlling at least one of the first control switch and the second control switch to be in an off state includes: When the cell voltage is lower than the processor's operating voltage, the first control switch is controlled to be in the ON state, and the second control switch is controlled to be in the OFF state, so that the current flowing into the connector passes through the second diode and the first control switch to charge the cell; the control method further includes: Obtain the charging voltage of the battery cell after charging; When the voltage of the charging cell is greater than the operating voltage of the processor, both the first control switch and the second control switch are controlled to be in the on state.

6. The control method according to claim 4, characterized in that, When the battery protection circuit is in a first operating state, controlling at least one of the first control switch and the second control switch to be in an off state includes: When the cell voltage is lower than the processor's operating voltage, the first control switch is controlled to be in a semi-conducting state, and the second control switch is controlled to be in a conducting state, so that the current flowing into the connector flows through the second control switch and the first control switch to charge the cell; the control method further includes: Obtain the charging voltage of the battery cell after charging; When the voltage of the charging cell is greater than the operating voltage of the processor, both the first control switch and the second control switch are controlled to be in the on state.

7. The control method according to claim 6, characterized in that, Before acquiring the charged cell voltage after charging, the control method further includes: Obtain the voltage difference between the voltages at both ends of the first control switch; If the voltage difference is greater than a preset threshold, the charging cell voltage after charging is obtained, wherein the preset threshold is the difference between the processor's operating voltage and the cell voltage.

8. The control method according to claim 7, characterized in that, The control method further includes: If the voltage difference is less than a preset threshold, the impedance of the first control switch is adjusted to adjust the voltage difference between the two ends of the first control switch so that the voltage difference is greater than the preset threshold.

9. An electronic device, characterized in that, The electronic device includes the battery protection circuit according to any one of claims 1-2.

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