CN116264407A - Protection circuit of silicon-oxygen negative electrode battery and silicon-oxygen negative electrode battery - Google Patents

Abstract

The present application provides a protection circuit for a silicon-oxygen negative electrode battery and a silicon-oxygen negative electrode battery. The protection circuit includes a boost circuit and a control terminal. The boost circuit is electrically connected to the battery core. The controller includes a detection terminal and a control terminal. The detection end is electrically connected to the battery cell, and is used for detecting the output voltage of the battery cell. The control terminal is electrically connected to the boost circuit. When the output voltage of the battery cell at the control terminal is in the high-voltage discharge voltage range, the control boost circuit does not work; when the output voltage of the battery cell is in the low-voltage discharge voltage range lower than the high-voltage discharge voltage range, the control boost circuit turns the The output voltage rises. The silicon-oxygen negative electrode battery includes a cell and a protection circuit. In this way, when the controller detects that the output voltage of the battery cell is in the low-voltage discharge voltage range, the booster circuit is controlled to increase the output voltage of the battery cell, so that the increased output voltage can continue to supply power to the load, reducing the battery life. capacity loss.

Description

Protection circuit of silicon-oxygen negative electrode battery and silicon-oxygen negative electrode battery

technical field

The present application relates to the field of batteries, in particular to a protection circuit for a silicon-oxygen negative electrode battery and a silicon-oxygen negative electrode battery.

Background technique

Currently, lithium batteries used in electronic devices include graphite negative electrodes and silicon-oxygen negative electrodes. Under the same battery volume, the discharge capacity of the silicon-oxygen negative electrode battery is larger than that of the graphite negative electrode battery. Therefore, the application of the silicon-oxygen negative electrode battery is gradually widespread. However, in the low-voltage range, the discharge capacity of the silicon-oxygen negative electrode battery is larger than that of the graphite negative electrode battery, and the discharge cut-off voltage of the silicon-oxygen negative electrode battery can reach 2.75V, but the shutdown voltage of the load may be higher than the discharge cut-off voltage of the silicon-oxygen negative electrode battery. , for example 3.3V. In this way, when the voltage of the silicon-oxygen negative electrode battery is lower than the shutdown voltage of the load, the load cannot work normally. The problem of large capacity loss.

Contents of the invention

The present application provides a protection circuit and a silicon-oxygen negative battery aiming at reducing the capacity loss of the silicon-oxygen negative battery.

The present application provides a protection circuit for a silicon-oxygen negative electrode battery, the silicon-oxygen negative electrode battery includes a battery cell, wherein the protection circuit includes:

a boost circuit electrically connected to the battery cell; and

The controller includes a detection terminal and a control terminal; the detection terminal is electrically connected to the battery cell for detecting the output voltage of the battery core; and the control terminal is electrically connected to the boost circuit; the control terminal is connected to the When the output voltage of the cell is in the high-voltage discharge voltage range, the booster circuit is controlled not to work; when the output voltage of the cell is in the low-voltage discharge voltage range lower than the high-voltage discharge voltage range, the The boost circuit boosts the output voltage of the cell.

Optionally, the protection circuit also includes:

Overcurrent protection circuit;

a switch circuit electrically connected between the overcurrent protection circuit and the battery core;

The overcurrent protection circuit is used to control the switching circuit to turn off when the battery cell is overcharged or overdischarged.

Optionally, the overcurrent protection circuit includes a battery detection pin and a power supply pin; the battery detection pin is electrically connected to the detection terminal; the power supply pin is electrically connected to the battery cell and the switch circuit Between; the controller detects the output voltage of the battery cell through the battery detection pin and the power supply pin.

Optionally, the overcurrent protection circuit includes a first protection chip and a first discharge capacitor; the battery detection pin and the power supply pin are set on the first protection chip; the first discharge capacitor is electrically connected to between the battery cell and the power supply pin, for supplying power to the first protection chip; and

The overcurrent protection circuit includes a second protection chip and a second discharge capacitor; the second protection chip includes a first power supply pin electrically connected to the electric core; the second discharge capacitor is electrically connected to the electric core between the first power supply pin and the second protection chip.

Optionally, the protection circuit includes an output terminal and an anti-current backflow circuit; the anti-current backflow circuit is electrically connected between the battery cell and the output terminal, and is electrically connected to the boost circuit for When the boost circuit boosts the output voltage of the battery cell, it prevents the current from flowing from the output terminal to the battery cell, and when the output voltage of the battery cell is in the high-voltage discharge voltage range, it connects the cell and the output.

Optionally, the anti-current backflow circuit includes a first switch tube and a second switch tube connected back to back in series, and the second switch tube is electrically connected between the first switch tube and the output terminal;

The boost circuit includes a boost input terminal and a boost output terminal, the boost input terminal is electrically connected between the battery cell and the first switch tube, and the boost output terminal is electrically connected to the output terminal, the boost circuit includes an enable pin electrically connected to the control terminal of the controller.

Optionally, the first switch transistor includes a first PMOS transistor, the second switch transistor includes a second PMOS transistor, the drain of the first PMOS transistor is electrically connected to the cell, and the first PMOS transistor The source of the tube is electrically connected to the source of the second PMOS tube; the drain of the second PMOS tube is electrically connected to the output terminal; the gate of the first PMOS tube and the gate of the second PMOS tube The poles are electrically connected to the control terminal of the controller.

Optionally, the anti-current backflow circuit includes a first diode and a second diode; the anode of the first diode is connected to the source of the first PMOS transistor, and the first diode The cathode of the second diode is electrically connected to the drain of the first PMOS transistor; the anode of the second diode is electrically connected to the source of the second PMOS transistor, and the cathode of the second diode is electrically connected to the second The drain of the PMOS transistor.

Optionally, the overcurrent protection circuit includes a first protection chip and a second protection chip; the first protection chip includes a first charging output pin, and the second protection chip includes a second charging output pin;

The switching circuit includes a third switching tube and a fourth switching tube; the first charging output pin is electrically connected to the control terminal of the third switching tube, and the second charging output pin is electrically connected to the fourth switching tube the control end of the tube;

When the cell is overcharged, the first protection chip and the second protection chip control the third switch tube and the fourth switch tube to be turned off.

Optionally, the first protection chip includes a first discharge output pin, and the second protection chip includes a second discharge output pin;

The switching circuit includes a fifth switching tube and a sixth switching tube; the first discharge output pin is electrically connected to the control terminal of the fifth switching tube, and the second discharging output pin is electrically connected to the sixth switch the control end of the tube;

When the cell is over-discharged, the first protection chip and the second protection chip control the fifth switch tube and the sixth switch tube to be turned off.

The present application also provides a silicon-oxygen negative electrode battery, which includes a cell; and

As in the protection circuit described above, the protection circuit is electrically connected between the positive pole and the negative pole of the battery cell.

The protection circuit of the silicon-oxygen negative electrode battery provided by the application. The protection circuit includes a boost circuit and a control terminal. The boost circuit is electrically connected to the battery cell. The controller includes a detection terminal and a control terminal. The detection terminal is electrically connected to the battery cell, and is used for detecting the output voltage of the battery cell. The control terminal is electrically connected to the boost circuit. When the output voltage of the battery cell at the control terminal is in the high-voltage discharge voltage range, the control booster circuit does not work; when the output voltage of the battery cell is in the low-voltage discharge voltage range lower than the high-voltage discharge voltage range, the control booster circuit will The output voltage rises. In this way, when the controller detects that the output voltage of the battery cell is in the low-voltage discharge voltage range, the booster circuit is controlled to increase the output voltage of the battery cell, so that the increased output voltage can continue to supply power to the load, reducing the battery life. capacity loss.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Description of drawings

Fig. 1 shows the circuit block diagram of the silicon-oxygen negative electrode battery of the present application;

Fig. 2 shows the comparison schematic diagram of the discharge situation of the silicon-oxygen negative electrode battery of the present application and the discharge situation of the graphite negative electrode battery;

Fig. 3 is a functional block diagram of an embodiment of the protection circuit of the silicon-oxygen negative electrode battery shown in Fig. 1;

FIG. 4 is a circuit diagram of the protection circuit of the silicon-oxygen negative electrode battery shown in FIG. 3 .

Detailed ways

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. Embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of means consistent with aspects of the present application as recited in the appended claims.

The terminology used in this application is for the purpose of describing particular embodiments only, and is not intended to limit the application. Unless otherwise defined, the technical terms or scientific terms used in the application shall have the ordinary meanings understood by those skilled in the art to which the application belongs. "First", "second" and similar words used in the specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Likewise, words like "a" or "one" do not denote a limitation in quantity, but indicate that there is at least one. "Multiple" or "several" means two or more. Unless otherwise indicated, terms such as "front", "rear", "lower" and/or "upper" are used for convenience of description only and are not intended to be limiting to a position or orientation in space. "Includes" or "comprises" and similar terms mean that the elements or items listed before "comprises" or "comprises" include the elements or items listed after "comprises" or "comprises" and their equivalents, and do not exclude other elements or objects. Words such as "connected" or "connected" are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect. As used in this specification and the appended claims, the singular forms "a", "the" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

The protection circuit of the silicon-oxygen negative electrode battery provided by the application. The silicon-oxygen negative electrode battery includes a cell. The protection circuit includes a boost circuit and a controller. The boost circuit is electrically connected to the battery cell. The controller includes a detection terminal and a control terminal. The detection terminal is electrically connected to the battery cell, and is used for detecting the output voltage of the battery cell. The control terminal is electrically connected to the boost circuit. When the output voltage of the battery cell is in the high-voltage discharge voltage range through the control terminal, the controller controls the boost circuit to not work; when the output voltage of the cell is in the low-voltage discharge voltage range lower than the high-voltage discharge voltage range, the control boost circuit will The output voltage of the cell increases. In this way, when the controller detects that the output voltage of the battery cell is in the low-voltage discharge voltage range, the booster circuit is controlled to increase the output voltage of the battery cell, so that the increased output voltage can continue to supply power to the load, reducing the battery life. capacity loss.

The present application also provides a silicon-oxygen negative electrode battery, including a battery cell and a protection circuit. The protection circuit is electrically connected between the positive pole and the negative pole of the electric core.

FIG. 1 is a circuit block diagram of a silicon-oxygen negative electrode battery 1 provided by the present application. As shown in FIG. 1 , a silicon-oxygen negative electrode battery 1 includes a cell 2 and a protection circuit 3 . The protection circuit 3 is electrically connected between the positive pole and the negative pole of the battery cell 2 . The protection circuit 3 is used to prevent the cell 2 from overcharging, over-discharging, over-current and short circuit, so as to prolong the service life of the cell 2 .

FIG. 2 is a schematic diagram showing the comparison between the discharge conditions of the silicon-oxygen negative electrode battery 1 provided in the present application and the discharge conditions of the graphite negative electrode battery. As shown in FIG. 2 , the abscissa is the battery capacity Q, and the unit is: mAH (milliampere-hour). The ordinate is the battery discharge cut-off voltage U, the unit is: V (volt). The discharge cut-off voltage of graphite negative electrode battery is 3.0V, and its corresponding battery capacity is Q1. The discharge cut-off voltage of the silicon-oxygen negative electrode battery is 2.75V, and its corresponding battery capacity is Q2. It can be seen from the figure that Q2>Q1, that is to say, the silicon-oxygen negative electrode battery can consume more battery capacity at its corresponding discharge cut-off voltage than the graphite negative electrode battery can consume at its corresponding discharge cut-off voltage. In this way, compared with the scheme of the graphite negative electrode battery, the capacity utilization rate of the silicon-oxygen negative electrode battery of the present application is higher.

FIG. 3 is a functional block diagram of an embodiment of the protection circuit 3 of the silicon-oxygen negative electrode battery 1 shown in FIG. 1 . As shown in FIG. 3 , the protection circuit 3 includes a boost circuit 4 and a controller 5 . The boost circuit 4 is electrically connected to the battery cell 2 . The controller 5 includes a detection terminal 6 and a control terminal 7 . The detection terminal 6 is electrically connected to the battery cell 2 for detecting the output voltage of the battery cell 2; and the control terminal 7 is electrically connected to the boost circuit 4; when the output voltage of the battery cell 2 is within the high-voltage discharge voltage range, the control terminal 7 controls the boost The circuit 4 does not work. When the output voltage of the cell 2 is in the low voltage discharge voltage range lower than the high voltage discharge voltage range, the boost circuit 4 is controlled to increase the output voltage of the cell 2 . In this embodiment, the controller 5 detects the output voltage of the battery cell 2 in real time through the detection terminal 6 . When it is detected that the output voltage of the battery cell 2 is in the high-voltage discharge voltage range (for example, 4.45V-3.3V), the load connected to the silicon-oxygen negative battery 1 can work normally. At this time, in some embodiments, the controller 5 pulls down the voltage electrically connected to the control terminal 7 of the boost circuit 4 , so that the boost circuit 4 does not work. When detecting that the output voltage of the battery cell 2 is in the low-voltage discharge voltage range (for example, 3.3V-2.75V), the controller 5 pulls up the voltage of the control terminal 7 to make the booster circuit 4 work. The boost circuit 4 can increase the output voltage of the cell 2 to continue supplying power to the load. In this way, when the output voltage of the battery cell 2 is in the low-voltage discharge voltage range, the normal power supply demand of the load can still be guaranteed, thereby reducing the capacity loss of the battery cell 2 . In addition, it should be noted that the high-voltage discharge voltage range and the low-voltage discharge voltage range in this embodiment are relative, and there is no specific definition. Wherein, the high-voltage discharge voltage range refers to a voltage range in which the battery cell 2 is allowed to discharge under normal conditions, which satisfies the normal operation of the load. The low-voltage discharge voltage range refers to a voltage range that is greater than the discharge cut-off voltage of the cell 2 of the silicon-oxygen negative electrode battery 1 and less than the load shutdown voltage.

In some embodiments, the protection circuit 3 further includes an overcurrent protection circuit 8 and a switch circuit 9 . The switch circuit 9 is electrically connected between the overcurrent protection circuit 8 and the battery cell 2 . The overcurrent protection circuit 8 is used to control the switch circuit 9 to turn off when the cell 2 is overcharged or overdischarged. In this embodiment, the overcurrent protection circuit 8 is used to control the switch circuit 9 to turn off when the cell 2 is overcharged or overdischarged, so that the cell 2 stops charging or discharging. The overcurrent protection circuit 8 has the function of protecting the battery cell 2 and prolonging the service life of the battery cell 2 .

FIG. 4 is a circuit diagram of the protection circuit 3 of the silicon-oxygen negative electrode battery 1 shown in FIG. 3 . 3 and 4, in some embodiments, the overcurrent protection circuit 8 includes a battery detection pin BS and a power supply pin VSS; the battery detection pin BS is electrically connected to the detection terminal 6; the power supply pin VSS is electrically connected to Between the battery cell 2 and the switch circuit 9; the controller 5 detects the output voltage of the battery cell 2 through the battery detection pin BS and the power supply pin VSS. In this embodiment, the detection terminal 6 of the controller 5 is electrically connected to the battery cell 2 through the overcurrent protection circuit 8 to realize the detection of the output voltage of the battery cell 2 . In this way, compared to the technical solution in the related art where the detection terminal 6 is electrically connected to the output terminal of the protection circuit 3 and detects the output voltage of the battery cell 2 through the switch circuit 9, the controller 5 of the embodiment of the present application can avoid the circuit of the switch circuit 9 Impedance, thereby improving the detection accuracy of the output voltage of the cell 2.

In some embodiments, the overcurrent protection circuit 8 includes a first protection chip IC1 and a first discharge capacitor C1. The battery detection pin BS and the power supply pin VSS are set on the first protection chip IC1. The overcurrent protection circuit 8 can realize the overcurrent protection for the battery cell 2 through the first protection chip IC1. The first protection chip IC1 is a primary protection chip and also an active component protection chip. Compared with the related art, the first protection chip IC1 of the present application is provided with a battery detection pin BS. The battery detection pin BS can be electrically connected to the negative pole of the battery cell 2 through the power supply pin VSS, so that the detection terminal 6 of the controller 5 can detect the output voltage of the battery cell 2 through the switch circuit 9, so that the controller 5 The accuracy of detecting the output voltage of the cell 2 is higher. The first discharge capacitor C1 is electrically connected between the battery cell 2 and the power pin VSS, and is used to supply power to the first protection chip IC1 to ensure the normal operation of the first protection chip IC1.

In some embodiments, the overcurrent protection circuit 8 includes a second protection chip IC2 and a second discharge capacitor C2 ; the second protection chip IC2 includes a first power supply pin VSS1 electrically connected to the battery cell 2 . In this embodiment, the overcurrent protection circuit 8 also realizes the overcurrent protection for the battery cell 2 through the second protection chip IC2, so that the effect of the overcurrent protection for the battery cell 2 is better. The second protection chip IC2 is a secondary protection chip and also a passive component protection chip. The second discharge capacitor C2 is electrically connected between the battery cell 2 and the first power supply pin VSS1, and is used to supply power to the second protection chip IC2, so as to ensure the normal operation of the second protection chip IC2.

In some embodiments, the first protection chip IC1 includes a first charging output pin COUT1, and the second protection chip IC2 includes a second charging output pin COUT2. The switching circuit 9 includes a third switching tube G3 and a fourth switching tube G4; the first charging output pin COUT1 is electrically connected to the control terminal of the third switching tube D3, and the second charging output pin COUT2 is electrically connected to the control terminal of the fourth switching tube . When the cell is overcharged, the first protection chip IC1 and the second protection chip IC2 control the third switching tube G3 and the fourth switching tube G4 to be turned off. The overcurrent protection circuit 8 implements overcurrent protection for the battery cell 2 through the protection chip. The first protection chip IC1 performs actions earlier than the second protection chip IC2. Specifically, when the battery cell 2 is in the overcharged state, the first protection chip IC1 first controls the third switching tube G3 to turn off through the first charging output pin COUT1, and then the second protection chip IC2 controls the third switching tube G3 to turn off through the second charging output pin COUT1. COUT2 controls the fourth switching tube G3 to turn off. In this way, the battery cell 2 can be prevented from continuing to be in a charged state, so as to prevent the battery cell 2 from being damaged due to overcharging. In some embodiments, both the third switching transistor G3 and the fourth switching transistor G4 are N-type MOS transistors.

In some embodiments, the first protection chip IC1 includes a first discharge output pin DOUT1, and the second protection chip IC2 includes a second discharge output pin DOUT2. The switch circuit 9 includes a fifth switch tube G5 and a sixth switch tube G6; the first discharge output pin DOUT1 is electrically connected to the control terminal of the fifth switch tube G5, and the second discharge output pin DOUT2 is electrically connected to the control terminal of the sixth switch tube G6. end. When the cell 2 is over-discharged, the first protection chip IC1 and the second protection chip IC2 control the fifth switch G5 and the sixth switch G6 to turn off. In this embodiment, when the cell 2 is in the over-discharge state, the first protection chip IC1 first controls the fifth switch tube G5 to turn off through the first discharge output pin DOUT1, and then the second protection chip IC2 outputs The pin DOUT2 controls the sixth switch tube G6 to turn off. In this way, the battery cell 2 can be prevented from continuing to be in a discharge state, so as to prevent the battery cell 2 from being damaged due to over-discharge. In some embodiments, both the fifth switching transistor G5 and the sixth switching transistor G6 are N-type MOS transistors.

In some embodiments, the overcurrent protection circuit includes a first current limiting resistor R1 and a second current limiting resistor R4. The first protection chip IC1 includes a chip working voltage pin VDD. The second protection chip IC2 includes the first chip working voltage VDD1. The first current limiting resistor R1 is electrically connected between the battery cell 2 and the chip working voltage pin VDD, and is used to limit the current input from the battery cell 2 to the first protection chip IC1. The second current limiting resistor R4 is electrically connected to the battery cell 2 and the first chip working voltage VDD1, and is used to limit the current input from the battery cell 2 to the second protection chip IC2.

In some embodiments, the overcurrent protection circuit further includes a first detection resistor R2 and a second detection resistor R3. The first protection chip IC1 includes a voltage pin V-. The second protection chip IC2 includes a first voltage pin V1-. The first detection resistor R2 is connected in series between the voltage pin V− and the output terminal 12 . The second detection resistor R3 is connected in series between the first voltage pin V1 − and the switch circuit 9 . Both the first detection resistor R2 and the second detection resistor R3 can detect whether the output terminal 12 is connected to a charger.

In some embodiments, the protection circuit 3 includes an output terminal 12 and an anti-current backflow circuit 10; the anti-current backflow circuit 10 is electrically connected between the battery cell 2 and the output terminal 12, and is electrically connected to the boost circuit 4 for use in When the boost circuit 4 increases the output voltage of the battery cell 2, it prevents the current from flowing from the output terminal 12 to the battery cell 2, and connects the battery cell 2 and the output terminal 12 when the output voltage of the battery cell 2 is in the high-voltage discharge voltage range. The output terminal 12 may include a positive output terminal P+ and a negative output terminal P−. When the booster circuit 4 boosts the output voltage of the battery cell 2 and outputs it to the positive output terminal P+, at this time, the voltage of the positive output terminal P+ is greater than the voltage of the battery cell 2, which will cause the voltage of the positive output terminal P+ to flow back to the battery. Core 2 problem. Therefore, an anti-current backflow circuit 10 is provided between the battery cell 2 and the positive output terminal P+, which can prevent the problem of current backflow from the positive output terminal P+ to the battery cell 2 when the voltage of the positive output terminal P+ is greater than the voltage of the battery cell 2. Therefore, the battery cell 2 is not easily damaged.

In some embodiments, the current backflow prevention circuit 10 includes a first switch G1 and a second switch G2 connected in series back to back, and the second switch G2 is electrically connected between the first switch G1 and the output terminal 12 . When the boost circuit 4 boosts the output voltage of the cell 2 and outputs it to the positive output terminal P+ of the output terminal 12, both the first switching tube G1 and the second switching tube G2 are in the off state, because the first switching tube G1 It is connected back to back in series with the second switching tube G2, so that the current flowing from the cell 2 to the first switching tube G1 and the current flowing from the positive output terminal P+ to the second switching tube G2 are all cut off. In this way, when the voltage of the positive output terminal P+ is greater than the voltage of the battery cell 2 , the purpose of preventing the current from flowing backward from the positive output terminal P+ to the battery cell 2 is achieved.

The boost circuit 4 includes a boost input terminal Vin and a boost output terminal Vout, the boost input terminal Vin is electrically connected between the cell 2 and the first switch tube G1, the boost output terminal Vout is electrically connected to the output terminal 12, and the boost The circuit 4 includes an enable pin EN electrically connected to the control terminal 7 of the controller 5 . The boost input terminal Vin is electrically connected to the cell 2 before the first switching tube G1, so that the boost circuit 4 directly boosts the output voltage of the cell 2, thereby improving the electrical efficiency of the output voltage of the cell 2. The boost circuit 4 boosts the output voltage of the battery cell 2 and outputs it to the positive output terminal P+ of the output terminal 12 through the boost output terminal Vout to further supply power to the whole machine. In addition, the electrical connection between the controller 5 and the boost circuit 4 is realized by electrically connecting the enable pin EN to the control terminal 7 , thereby facilitating the control of the boost circuit 4 by the controller 5 through the enable pin EN.

In some embodiments, the boost circuit 4 includes, but is not limited to, a charge pump. The boost circuit 4 boosts the output voltage of the battery cell 2 through a charge pump and then outputs it to the positive output terminal P+, which has higher boost efficiency than the solution using a boost boost circuit. In some embodiments, the electrical efficiency of the charge pump can reach more than 95%. In some embodiments, the charge pump can increase the output voltage of the battery cell 2 by 1.5 times. In some embodiments, the charge pump includes two parallel switches SC, two capacitors C and an N-type MOS transistor Q1. The two capacitors C are respectively connected in parallel with the two switches SC. The source of the N-type MOS transistor Q1 is electrically connected to one of the switches SC, and the drain is electrically connected to the cell 2 .

In some embodiments, the first switching transistor G1 includes a first PMOS transistor, the second switching transistor G2 includes a second PMOS transistor, the drain of the first PMOS transistor is electrically connected to the cell 2, and the source electrode of the first PMOS transistor The source of the second PMOS transistor is connected; the drain of the second PMOS transistor is electrically connected to the output terminal 12; the gate of the first PMOS transistor and the gate of the second PMOS transistor are both electrically connected to the control terminal 7 of the controller 5 . Both the first switching tube G1 and the second switching tube G2 are P-type MOS tubes. According to the low-voltage conduction and high-voltage cut-off characteristics of the P-type MOS tube, when the booster circuit 4 outputs a high voltage, both the first switch tube G1 and the second switch tube G2 are turned off, so that the current can be prevented from flowing from the output terminal 12. The purpose of pouring the positive output terminal P+ into the battery cell 2. In addition, the controller 5 is electrically connected to the common gates of the first switching transistor G1 and the second switching transistor G2 through the control terminal 7 to control whether the first switching transistor G1 and the second switching transistor G2 are turned on or off.

In some embodiments, the current backflow prevention circuit 10 includes a first diode D1 and a second diode D2; the anode of the first diode D1 is connected to the source of the first PMOS transistor, and the first diode D1 The cathode of the second diode D2 is electrically connected to the drain of the first PMOS transistor; the anode of the second diode D2 is electrically connected to the source of the second PMOS transistor, and the cathode of the second diode D2 is electrically connected to the drain of the second PMOS transistor. The first diode D1 and the second diode D2 are parasitic diodes, which are used to prevent the breakdown of the first PMOS transistor and the second PMOS transistor when an instantaneous reverse current is generated in the circuit, so as to protect the first PMOS transistor and the second PMOS transistor. The role of the second PMOS tube. According to the unidirectional conductivity of the diodes, the cathode of the first diode D1 is electrically connected to the cell 2 , and the cathode of the second diode D2 is electrically connected to the positive output terminal P+. In this way, when the voltage of the positive output terminal P+ is greater than the voltage of the battery cell 2 , the voltage at the positive output terminal P+ is prevented from being poured back into the battery cell 2 .

In some embodiments, the protection circuit 3 includes a temperature detection circuit 11 electrically connected between the battery cell 2 and the controller 5 for detecting the temperature of the battery cell 2 . When the battery cell 2 is in a discharging state or a charging state, the temperature detection circuit 11 can detect the temperature of the battery cell 2 in real time and feed it back to the controller 5 . If the temperature of the battery cell 2 is too high, the controller 5 blocks the battery cell 2 from continuing to discharge or charge. In some embodiments, the temperature detection circuit 11 includes a thermistor NTC.

In some embodiments, the protection circuit 3 includes a precision resistor RS connected in series between the power supply pin VSS and the switch circuit 9 for detecting the current of the battery cell 2 .

The above description is only the preferred implementation mode of the application, and does not limit the application in any form. Although the application has disclosed the above with the preferred implementation mode, it is not used to limit the application. Anyone who is familiar with this professional technology Personnel, without departing from the scope of the technical solution of the present application, when using the technical content disclosed above to make some changes or modifications to equivalent implementations with equivalent changes, but any content that does not depart from the technical solution of the present application, according to the technical content of the present application Any simple modifications, equivalent changes and modifications made by the technical essence of the application to the above implementation methods still fall within the scope of the technical solution of the application.

Claims (11)

1. A protective circuit for a silicon-oxygen negative electrode battery, said silicon-oxygen negative electrode battery comprising an electric core, characterized in that said protective circuit comprises: a boost circuit electrically connected to the battery cell; and The controller includes a detection terminal and a control terminal; the detection terminal is electrically connected to the battery cell for detecting the output voltage of the battery core; and the control terminal is electrically connected to the boost circuit; the control terminal is connected to the When the output voltage of the cell is in the high-voltage discharge voltage range, the booster circuit is controlled not to work; when the output voltage of the cell is in the low-voltage discharge voltage range lower than the high-voltage discharge voltage range, the The boost circuit boosts the output voltage of the cell. 2. The protection circuit according to claim 1, wherein the protection circuit further comprises: Overcurrent protection circuit; a switch circuit electrically connected between the overcurrent protection circuit and the battery core; The overcurrent protection circuit is used to control the switching circuit to turn off when the battery cell is overcharged or overdischarged. 3. The protection circuit according to claim 2, wherein the overcurrent protection circuit includes a battery detection pin and a power supply pin; the battery detection pin is electrically connected to the detection terminal; the power supply pin Electrically connected between the battery cell and the switch circuit; the controller detects the output voltage of the battery cell through the battery detection pin and the power supply pin. 4. The protection circuit according to claim 3, wherein the overcurrent protection circuit comprises a first protection chip and a first discharge capacitor; the battery detection pin and the power supply pin are arranged on the second A protection chip; the first discharge capacitor is electrically connected between the battery core and the power supply pin, and is used to supply power to the first protection chip; and The overcurrent protection circuit includes a second protection chip and a second discharge capacitor; the second protection chip includes a first power supply pin electrically connected to the electric core; the second discharge capacitor is electrically connected to the electric core between the first power supply pin and the second protection chip. 5. The protection circuit according to claim 2, wherein the protection circuit comprises an output terminal and an anti-current inflow circuit; the anti-current inflow circuit is electrically connected between the battery core and the output terminal, And it is electrically connected with the boost circuit, and is used to prevent the current from flowing from the output end to the battery core when the boost circuit increases the output voltage of the battery core. When the output voltage is within the high-voltage discharge voltage range, the battery core is connected to the output terminal. 6. The protection circuit according to claim 5, wherein the anti-current backflow circuit comprises a first switching tube and a second switching tube connected in series back to back, and the second switching tube is electrically connected to the first switching tube. Between the switch tube and the output terminal; The boost circuit includes a boost input terminal and a boost output terminal, the boost input terminal is electrically connected between the battery cell and the first switch tube, and the boost output terminal is electrically connected to the output terminal, the boost circuit includes an enable pin electrically connected to the control terminal of the controller. 7. The protection circuit according to claim 6, wherein the first switch transistor includes a first PMOS transistor, the second switch transistor includes a second PMOS transistor, and the drain electrode of the first PMOS transistor Connected to the cell, the source of the first PMOS transistor is electrically connected to the source of the second PMOS transistor; the drain of the second PMOS transistor is electrically connected to the output terminal; the first PMOS transistor The gate of the transistor and the gate of the second PMOS transistor are both electrically connected to the control terminal of the controller. 8. The protection circuit according to claim 7, wherein the anti-current backflow circuit comprises a first diode and a second diode; the anode of the first diode is connected to the first PMOS The source of the transistor, the cathode of the first diode is electrically connected to the drain of the first PMOS transistor; the anode of the second diode is electrically connected to the source of the second PMOS transistor, and the first diode is electrically connected to the source of the second PMOS transistor. The cathodes of the two diodes are electrically connected to the drain of the second PMOS transistor. 9. The protection circuit according to claim 2, wherein the overcurrent protection circuit comprises a first protection chip and a second protection chip; the first protection chip comprises a first charging output pin, and the first protection chip The second protection chip includes a second charging output pin; The switching circuit includes a third switching tube and a fourth switching tube; the first charging output pin is electrically connected to the control terminal of the third switching tube, and the second charging output pin is electrically connected to the fourth switching tube the control end of the tube; When the cell is overcharged, the first protection chip and the second protection chip control the third switch tube and the fourth switch tube to be turned off. 10. The protection circuit according to claim 9, wherein the first protection chip includes a first discharge output pin, and the second protection chip includes a second discharge output pin; The switching circuit includes a fifth switching tube and a sixth switching tube; the first discharge output pin is electrically connected to the control terminal of the fifth switching tube, and the second discharging output pin is electrically connected to the sixth switch the control end of the tube; When the cell is over-discharged, the first protection chip and the second protection chip control the fifth switch tube and the sixth switch tube to be turned off. 11. A silicon-oxygen negative electrode battery, characterized in that it includes a battery cell; and The protection circuit according to any one of claims 1-10, wherein the protection circuit is electrically connected between the positive pole and the negative pole of the electric core.

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