Battery charging protection circuit, explosion-proof battery and electronic equipment

Abstract

The utility model provides a battery charging protection circuit, an explosion-proof battery and electronic equipment. The battery charging protection circuit comprises an overvoltage protection module and a temperature protection module, the overvoltage protection module comprises at least one overvoltage protection circuit, and the overvoltage protection circuit comprises a first comparison circuit and a first switching device; the temperature protection module comprises at least one temperature protection circuit, the temperature protection circuit comprises a high-temperature protection circuit and a low-temperature protection circuit, and the high-temperature protection circuit and the low-temperature protection circuit each comprise a second comparison circuit, a thermistor and a second switching device. Potential risk factors caused by overvoltage in the charging process are avoided through the overvoltage protection circuit, it is guaranteed that the battery is charged within the normal temperature range through the temperature protection circuit, the risks of floating charging, bulging, short circuit and the like of the battery are avoided, and therefore the charging safety of the explosion-proof battery can be effectively improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a circuit technical field especially relates to a battery charging protection circuit, explosion -proof battery and electronic equipment. BACKGROUND

[0002] In the place of long time existence flammable and explosive gas environment such as petroleum exploration, oil refinery, chemical plant, natural gas production transportation and storage, pharmaceutical factory, wine industry, gas station, the electronic product (for example mobile phone, panel, interphone and other intelligent terminal) of staff uses has strict anti -explosion level requirement, for example, the anti -explosion requirement level is highest for anti -explosion 0 area, anti -explosion I area is second, and the relative risk coefficient is relatively low in anti -explosion II area, and the anti -explosion requirement level is lower.In the working of electronic product, the pulse electric spark caused by large current and transient pulse current is easy to explode the combustible gas around, thereby causing fire and explosion and other security risks, and the explosion -proof battery can solve the problem to a certain extent.But the charging requirement of this kind of environment to the battery is more strict, this is because the unstable factors such as charging voltage, current fluctuation of battery in the charging process are easy to cause the generation of pulse electric spark, and the battery is easy to heat in the charging process, and the charging safety of battery is low, thereby the traditional explosion -proof battery is limited to discharge use in dangerous area. SUMMARY

[0003] The utility model provides a kind of battery charging protection circuit, explosion -proof battery and electronic equipment, to solve the problem of safety of explosion -proof battery provided in the related art in charging use scene.

[0004] To solve the above technical problems, the utility model provides a kind of battery charging protection circuit in the first aspect, comprising: overvoltage protection module and temperature protection module;The overvoltage protection module includes at least one overvoltage protection circuit, and the overvoltage protection circuit includes first comparison circuit and first switching device, and the first switching device is electrically connected with power supply and is used to be electrically connected with the battery unit outside, and the first comparison circuit is electrically connected with the first switching device and power supply respectively;The temperature protection module includes at least one temperature protection circuit, and the temperature protection circuit includes high temperature protection circuit and low temperature protection circuit, and the high temperature protection circuit and the low temperature protection circuit all include second comparison circuit, thermistor and second switching device, and the second comparison circuit is electrically connected with the second switching device, the thermistor and power supply respectively, and the second switching device of high temperature protection circuit is electrically connected with the second switching device of low temperature protection circuit and is used to be electrically connected with the battery unit, and the second switching device of low temperature protection circuit is also electrically connected with the first switching device.

[0005] Further, the battery charging protection circuit further comprises a charge and discharge cycle number detection and control circuit, the charge and discharge cycle number detection and control circuit comprises a power meter and a third switch device, the third switch device is electrically connected with the second switch device of the high-temperature protection circuit and is used for being electrically connected with the battery unit, the power meter is electrically connected with the third switch device, and the power meter is also used for being electrically connected with the battery unit and a terminal device outside.

[0006] Further, the overvoltage protection circuit further comprises a second resistor and a third resistor, the second resistor is electrically connected with a power supply and one end of the third resistor respectively, the other end of the third resistor is grounded, the first end of the first comparison circuit is electrically connected with the power supply, the second end of the first comparison circuit is electrically connected with one end of the third resistor, and the third end of the first comparison circuit is electrically connected with the first switch device.

[0007] Further, the low-temperature protection circuit and the high-temperature protection circuit both further comprise a fourth resistor, a fifth resistor and a sixth resistor, one end of the fourth resistor and the fifth resistor is electrically connected with a power supply respectively, the other end of the fourth resistor is electrically connected with the first end of the second comparison circuit and one end of the sixth resistor respectively, the other end of the fifth resistor is electrically connected with one end of the thermistor and the second end of the second comparison circuit respectively, the other end of the sixth resistor and the thermistor is grounded, the third end of the second comparison circuit is electrically connected with the power supply, the fourth end of the second comparison circuit is electrically connected with the second switch device, and the fifth end of the second comparison circuit is grounded.

[0008] The utility model discloses a second aspect provides a kind of explosion-proof battery, including the battery charging protection circuit as described in the utility model first aspect.

[0009] The utility model discloses a third aspect provides a kind of electronic equipment, including the battery charging protection circuit as described in the utility model first aspect or the explosion-proof battery as described in the utility model second aspect.

[0010] From the above description, the utility model discloses a potential dangerous factor caused by the fluctuation of voltage overvoltage during the charging process is avoided through overvoltage protection circuit, and the number of overvoltage protection circuit can be one or more, and the switching device in each overvoltage protection circuit can adaptively perform switching action according to the voltage comparison result of comparison circuit, thereby the charging of the battery unit by the power supply can be disconnected when the charging voltage is too large;The resistance value of thermistor in temperature protection circuit is changed in response to charging temperature, so that the switching device in temperature protection circuit adaptively performs switching action according to the voltage comparison result of comparison circuit, so as to cut off the charging of the battery unit by the power supply when the charging temperature exceeds the preset temperature range, thereby avoiding the safety risks such as battery floating charge and swelling caused by charging the battery in high-temperature environment, and avoiding the risk of battery positive and negative short circuit caused by charging the battery in low-temperature environment, and causing fire, etc.;Therefore, by combining overvoltage protection and temperature protection, the safety of explosion-proof battery charging can be effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 It is a structure schematic diagram of a battery charging protection circuit of the utility model embodiment;

[0012] Figure 2 It is another structure schematic diagram of a battery charging protection circuit of the utility model embodiment;

[0013] Figure 3 It is a circuit schematic diagram of a battery charging protection circuit of the utility model embodiment;

[0014] Figure 4 It is a circuit schematic diagram of an overvoltage protection module of the utility model embodiment. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the utility model more clear and obvious, the utility model is further explained in detail below in combination with the drawings and embodiments, wherein the same or similar signs represent the same or similar elements or elements with the same or similar functions throughout. It should be understood that the specific embodiments described herein are only used to explain the utility model and do not limit the utility model. In addition, the technical features involved in each embodiment of the utility model described below can be combined with each other as long as they do not conflict with each other.

[0016] In the related art, a general explosion-proof battery (lithium ion battery) is susceptible to voltage and charging ambient temperature when charging in a flammable and explosive hazardous area, which may cause fire, swelling, liquid leakage and other safety risks, wherein, when the battery is overcharged, especially high-temperature overvoltage charging, the battery is prone to swelling, fire and even explosion, and when the battery is charged at a temperature outside the safe charging temperature range, such as a temperature lower than 0℃, lithium ion battery internal electrode lithium precipitation may occur, and lithium precipitation deposition may produce relatively hard and sharp lithium dendrites on the electrode and the separator, and the lithium dendrites produced by long-term low-temperature charging may continuously grow, which may pierce the battery key component separator layer, causing the internal positive and negative electrodes of the battery to short circuit and cause fire; and when the battery is fully charged and overcharged in a high-temperature environment exceeding 45℃, the battery may be subjected to safety risks such as floating charging, gas production, swelling and liquid leakage, resulting in low charging safety of the explosion-proof battery. Therefore, the utility model embodiment provides a battery charging protection circuit.

[0017] As Figure 1 The battery charging protection circuit provided by the utility model embodiment is shown in the structure schematic diagram, which comprises: overvoltage protection module 100 and temperature protection module 200; overvoltage protection module 100 comprises at least one overvoltage protection circuit 110, and the overvoltage protection circuit comprises first comparison circuit 111 and first switch device 112, the first switch device is electrically connected with the power supply and is used for being electrically connected with the external battery unit 300, and the first comparison circuit VCM1 is electrically connected with the first switch device K1 and the power supply respectively; temperature protection module 200 comprises at least one temperature protection circuit 210, and the temperature protection circuit 210 comprises high-temperature protection circuit 211 and low-temperature protection circuit 212, wherein the high-temperature protection circuit 211 and the low-temperature protection circuit 212 both comprise second comparison circuit VCM2, thermistor R1 and second switch device K2, the second comparison circuit VCM2 is electrically connected with the second switch device K2, the thermistor R1 and the power supply respectively, the second switch device VCM2 of the high-temperature protection circuit 211 is electrically connected with the second switch device VCM2 of the low-temperature protection circuit 212 and is used for being electrically connected with the battery unit 300, and the second switch device K2 of the low-temperature protection circuit 212 is also electrically connected with the first switch device K1.

[0018] Specifically, the embodiment avoids potential dangerous factors caused by voltage overvoltage fluctuation during the charging process through the overvoltage protection circuit. The overvoltage protection circuit can be one or more. Each overvoltage protection circuit can detect the charging voltage through the first comparison circuit VCM1, and when the charging voltage is greater than the preset threshold voltage threshold, control the first switching device to be closed, thereby disconnecting the charging. The charging temperature is detected by the thermistor in the temperature protection circuit, and the temperature is judged by the second comparator circuit. When the charging temperature is greater than the preset temperature threshold, the second switching device is closed, thereby avoiding the safety risks of battery floating charging and swelling caused by charging the battery in a high-temperature environment, and avoiding the risk of battery positive and negative short circuit caused by charging the battery in a low-temperature environment, and triggering a fire. Therefore, by combining overvoltage protection and temperature protection, the safety of the explosion-proof battery charging can be effectively improved.

[0019] As Figure 2 shown is a structure schematic diagram of another battery charging protection circuit provided by the embodiment. Please refer to Figure 2 , the battery charging protection circuit further includes a charge-discharge cycle number detection and control circuit 400, the charge-discharge cycle number detection and control circuit 400 includes a power meter U1 and a third switching device K3, the third switching device K3 is electrically connected with the second switching device K2 of the high-temperature protection circuit 211 and is used to be electrically connected with the battery unit 300, the power meter U1 is electrically connected with the third switching device K3, and the power meter U1 is further used to be electrically connected with the battery unit 300 and the terminal device outside.

[0020] Further, as Figure 3 shown is a circuit principle diagram of a battery charging protection circuit provided by the embodiment. Please refer to Figure 3 , the battery charging protection circuit further includes a first resistor R2, one end of the first resistor R2 is used to be electrically connected with the battery unit 300, the other end of the first resistor R2 is respectively electrically connected with the first end CSP of the power meter U1, the second end VCELL, and the third switching device K3, and the other end of the first resistor R1 is further used to be electrically connected with the external load, the third end CSN of the power meter U1 is electrically connected with one end of the first resistor R2, the fourth end SW of the power meter U1 is electrically connected with the third switching device K3, the fifth end SCL, the sixth end SDA, and the seventh end INT_N of the power meter U1 are used to be electrically connected with the terminal device, and the eighth end VSS of the power meter U1 is grounded.

[0021] Specifically, the first resistor R2 is a charge-discharge current size detection resistor, one end of which is connected to the positive electrode of the battery unit 300 and the charge-discharge current detection input end CSN of the coulometer U1, and the other end is connected with the third switching device K3, the charge-discharge current detection input end CSP of the coulometer U1, the VCELL end of the coulometer U1, and an external load, respectively. The VCELL end of the coulometer U1 is used to measure the voltage of the battery, so as to calculate the remaining power or the state of charge of the battery. The SCL and SDA ends of the coulometer U1 are used for I2C communication, and the INT_N end of the coulometer U1 is used to receive an interrupt signal transmitted by an external terminal device.

[0022] In the embodiment, considering that the lithium ion battery generally has a limit on the number of safe use cycles (for example, 500 charge-discharge cycles), a battery that has been used for a long time beyond the number of safe cycles will increase the risk of battery swelling, liquid leakage, internal short circuit, fire, etc. Therefore, the battery charging protection circuit of the embodiment is also provided with a charge-discharge cycle number detection and control circuit 400. The coulometer in the detection and control circuit is used to record the charge-discharge cycle number of the battery from the factory to the use process of the battery, and accurately record the remaining power of the battery. In addition, the terminal device is informed of the recorded cumulative cycle number of the battery and the current remaining power of the battery through the I2C bus each time the terminal device is powered on, so as to determine whether it is the set “safe cycle life warning number” by the terminal device, so as to remind the user that the battery needs to be replaced when it reaches the cycle life, and if the user does not replace the battery, the coulometer will automatically output a control signal to close the battery charging path through the SW pin after the cumulative record reaches the “safe cycle life cutoff number”, control the third switching device to be disconnected, prevent the old battery beyond the cycle life from being charged in the dangerous zone, and inform the terminal device through the I2C bus that the battery can only be discharged and cannot be charged, and the power is exhausted. In addition, it should be noted that in the Figure 3 In the embodiment, the battery unit 300 includes the battery cell cell1 and the battery cell cell2, and the two battery cells are connected in series with the fuses F1 and F2, and the battery unit is also connected with the battery charge-discharge protection control chip IC1 to provide basic charge-discharge protection. The embodiment designs the charging protection circuit on the basis of the battery charge-discharge protection.

[0023] Further, referring to Figure 3 , the overvoltage protection circuit further includes a second resistor R3 and a third resistor R4, the second resistor R3 is electrically connected with the power supply and one end of the third resistor R4, the other end of the third resistor R4 is grounded, the first end of the first comparison circuit VCM1 is electrically connected with the power supply, the second end of the first comparison circuit VCM1 is electrically connected with one end of the third resistor R4, and the third end of the first comparison circuit VCM1 is electrically connected with the first switching device K1. The first switching device K1 can be a relay, and the second resistor R3 and the third resistor R4 constitute a resistor voltage dividing circuit.

[0024] Further, please refer to Figure 3 , the first comparison circuit VCM1 includes a first comparator U2, a reference voltage source and a first MOS tube Q1, the first end of the first comparator U2 is electrically connected with one end of the third resistor R4, the second end of the first comparator U2 is electrically connected with the reference voltage source, the third end of the first comparator U2 is electrically connected with the first end of the first MOS tube Q1, the fourth end of the first comparator U2 is electrically connected with the power supply, the second end of the first MOS tube Q1 is electrically connected with the first switching device K1, and the third end of the first MOS tube Q1 is grounded, wherein the first MOS tube Q1 can be an NMOS tube.

[0025] Specifically, in the embodiment, the overvoltage protection module 100 can include one or more overvoltage protection circuits 110, the first switching device K1 of each overvoltage protection circuit 110 is connected between the battery unit 300 and the charging power supply, the power supply end of the first comparison circuit VCM1 is connected to the charging power supply, if there is no external charging voltage input, the circuit of the module will not work, and the first switching device K1 connected by default is disconnected. When there is an external charging voltage input, the external charging input voltage is input into the comparator after being divided by a resistor with a proper ratio, and compared with the reference voltage (for example, 400 mV) of the comparator circuit itself, and a level signal for controlling the switch is output according to the comparison result, wherein if the voltage after the external charging voltage is divided is higher than the reference voltage, a control signal for disconnecting the external switch is output, and the type of the control signal can be determined by the on-off of the MOS tube; if the external charging voltage is equal to or lower than the reference voltage, a control signal for connecting the external switch is output, and only when the charging voltage detected by the comparator is lower than or equal to the reference voltage, the corresponding switch will be connected, which can ensure that the overvoltage cannot enter the battery, and the battery itself will not be charged by the overvoltage.

[0026] As Figure 4 shows a circuit principle diagram of an overvoltage protection module provided by the embodiment, please refer to Figure 4, the overvoltage protection module 100 comprises a first overvoltage protection circuit 110, a second overvoltage protection circuit 120 and a third overvoltage protection circuit 130; the first switch device K1 of the first overvoltage protection circuit 110 is electrically connected with the power supply and the first switch device K1 of the first overvoltage protection circuit 110 respectively, the first switch device K1 of the third overvoltage protection circuit 130 is electrically connected with the first switch device K1 of the second overvoltage protection circuit 120 and the second switch device K2 of the low-temperature protection circuit 212 respectively, and the first comparison circuit VCM1 of the first overvoltage protection circuit 110, the second overvoltage protection circuit 120 and the third overvoltage protection circuit 130 is electrically connected with the corresponding first switch device K1 respectively. Wherein, the structure of the first overvoltage protection circuit 110, the second overvoltage protection circuit 120 and the third overvoltage protection circuit 130 is same.

[0027] In the embodiment, in order to prevent the overvoltage protection circuit from failure, the overvoltage protection circuit can also be provided as multiple, for example, three, the three overvoltage protection circuits are connected in cascade, three layers of charging overvoltage protection are provided, each first comparison circuit VCM1 is connected with a first switch device K1, the first switch devices K1 are connected in series, and the power supply of each first comparison circuit VCM1 and the first switch device K1 is an external charging power supply. If there is no charging voltage input externally, each first comparison circuit VCM1 does not work, and the switch device is in an open state. By connecting the three overvoltage protection circuits in cascade, the charging voltage enters the battery only when and if the three overvoltage protection circuits detect that the charging voltage is lower than or equal to the reference voltage, thereby effectively improving the stability and reliability of the overvoltage protection.

[0028] Further, referring to Figure 3 , the low-temperature protection circuit 212 and the high-temperature protection circuit 211 further comprise a fourth resistor R5, a fifth resistor R6 and a sixth resistor R7, one end of the fourth resistor R5 and the fifth resistor R6 is electrically connected with the power supply, the other end of the fourth resistor R5 is electrically connected with the first end of the second comparison circuit VCM2 and one end of the sixth resistor R7 respectively, the other end of the fifth resistor R6 is electrically connected with one end of the thermistor R1 and the second end of the second comparison circuit VCM2 respectively, the other end of the sixth resistor R7 and the thermistor R1 is grounded, the third end of the second comparison circuit VCM2 is electrically connected with the power supply, the fourth end of the second comparison circuit VCM2 is electrically connected with the second switch device K2, and the fifth end of the second comparison circuit VCM2 is grounded. Wherein, the resistance voltage dividing circuit composed of the fourth resistor R5 and the sixth resistor R7 provides a reference voltage for the second comparison circuit VCM2, and the resistance voltage dividing circuit composed of the thermistor R1 and the fifth resistor R6 changes with the resistance value of the thermistor, and the changed voltage dividing is compared with the reference voltage, which can be used to judge whether the charging temperature exceeds the safe temperature range.

[0029] Further, referring toFigure 3 The second comparison circuit VCM2 comprises a second comparator U3 and a second MOS tube Q2, one end of the second comparator U3 is electrically connected with the other end of the fourth resistor R5, the second end of the second comparator U3 is electrically connected with the other end of the fifth resistor R6, the third end of the second comparator U3 is electrically connected with the first end of the second MOS tube Q2, the fourth end of the second comparator U3 is electrically connected with a power supply, the fifth end of the second comparator U3 is grounded, and the second end of the second MOS tube Q2 is electrically connected with the second switch device K2, and the third end of the second MOS tube Q2 is grounded.

[0030] Specifically, in the embodiment, the high-temperature protection circuit 211 and the low-temperature protection circuit 212 are powered by an external charging voltage, and the circuit will not work without the input of the charging voltage, and the switches connected to the circuit are turned off by default. The high-temperature protection circuit 211 and the low-temperature protection circuit 212 are connected to the NTC thermistor R1 for battery temperature detection. If the battery temperature is higher than the high-temperature threshold set by the comparator or lower than the low-temperature threshold set by the comparator, the comparator will output a cutoff signal to control the corresponding switch, thereby disconnecting the charging voltage input, and avoiding charging the battery in an environment with an over-temperature range. Only when the temperature of the battery is between the set low-temperature threshold and the high-temperature threshold, the two switch devices are turned on at the same time. The temperature protection circuit can also be designed as multiple, for example, two or three, to provide two or three layers of temperature protection functions, and prevent the protection circuit from failing.

[0031] The battery charging protection circuit provided by the embodiment of the utility model avoids potential dangerous factors caused by voltage overvoltage fluctuation in the charging process through the overvoltage protection circuit, the overvoltage protection circuit can be one or more, each overvoltage protection circuit can detect the charging voltage through the first comparison circuit, and when the charging voltage is greater than the preset threshold voltage threshold, the first switch device is controlled to be closed, thereby disconnecting the charging, the charging temperature is detected through the thermistor in the temperature protection circuit, and the temperature is judged through the second comparator circuit, when the charging temperature is greater than the preset temperature threshold, the second switch device is closed, thereby avoiding the safety risks such as battery floating charging and swelling caused by charging the battery in a high-temperature environment, and avoiding the battery positive and negative electrode short circuit caused by charging the battery in a low-temperature environment, and triggering the risk such as fire, therefore, the safety of the explosion-proof battery charging can be effectively improved by combining overvoltage protection and temperature protection.

[0032] The embodiment of the utility model further provides an explosion-proof battery, the explosion-proof battery comprises the battery charging protection circuit.

[0033] The embodiment of the utility model further provides an electronic equipment, the electronic equipment comprises the battery charging protection circuit or the explosion-proof battery.

[0034] It should be noted that each of the embodiments in the present application is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between embodiments can be referred to each other.

[0035] It should also be noted that in the present application, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0036] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown in the present application, but will conform to the widest scope consistent with the principles and novel features disclosed in the present application.

Claims

1. A battery charge protection circuit, characterized by, The application relates to a battery protection module. The overvoltage protection module comprises at least one overvoltage protection circuit, the overvoltage protection circuit comprises a first comparison circuit and a first switch device, the first switch device is electrically connected with a power supply and used for being electrically connected with an external battery unit, and the first comparison circuit is electrically connected with the first switch device and the power supply respectively. The temperature protection module comprises at least one temperature protection circuit, the temperature protection circuit comprises a high-temperature protection circuit and a low-temperature protection circuit, the high-temperature protection circuit and the low-temperature protection circuit both comprise a second comparison circuit, a thermistor and a second switch device, the second comparison circuit is electrically connected with the second switch device, the thermistor and the power supply respectively, the second switch device of the high-temperature protection circuit is electrically connected with the second switch device of the low-temperature protection circuit and used for being electrically connected with the battery unit, and the second switch device of the low-temperature protection circuit is also electrically connected with the first switch device. The application further comprises a charge-discharge cycle number detection and control circuit, the charge-discharge cycle number detection and control circuit comprises a power meter and a third switch device, the third switch device is electrically connected with the second switch device of the high-temperature protection circuit and used for being electrically connected with the battery unit, the power meter is electrically connected with the third switch device, and the power meter is also used for being electrically connected with the battery unit and an external terminal device.

2. The battery charge protection circuit of claim 1, wherein, The application further comprises a first resistor, one end of the first resistor is used for being electrically connected with the battery unit, the other end of the first resistor is electrically connected with a first end, a second end of the power meter and the third switch device respectively, and the other end of the first resistor is also used for being electrically connected with an external load, a third end of the power meter is electrically connected with one end of the first resistor, a fourth end of the power meter is electrically connected with the third switch device, a fifth end, a sixth end and a seventh end of the power meter are all used for being electrically connected with the terminal device, and an eighth end of the power meter is grounded.

3. The battery charge protection circuit of claim 2, wherein, The overvoltage protection circuit further comprises a second resistor and a third resistor, the second resistor is electrically connected with the power supply and one end of the third resistor respectively, the other end of the third resistor is grounded, a first end of the first comparison circuit is electrically connected with the power supply, a second end of the first comparison circuit is electrically connected with one end of the third resistor, and a third end of the first comparison circuit is electrically connected with the first switch device.

4. The battery charge protection circuit of claim 1, wherein, The first comparison circuit comprises a first comparator, a reference voltage source and a first MOS tube, a first end of the first comparator is electrically connected with one end of the third resistor, a second end of the first comparator is electrically connected with the reference voltage source, a third end of the first comparator is electrically connected with a first end of the first MOS tube, a fourth end of the first comparator is electrically connected with the power supply, a second end of the first MOS tube is electrically connected with the first switch device, and a third end of the first MOS tube is grounded.

5. The battery charge protection circuit of claim 4, wherein, ​ 6. The battery charge protection circuit of claim 1, wherein, Both the low-temperature protection circuit and the high-temperature protection circuit further include a fourth resistor, a fifth resistor, and a sixth resistor. One end of the fourth resistor and the fifth resistor are electrically connected to the power supply. The other end of the fourth resistor is electrically connected to the first terminal of the second comparison circuit and one end of the sixth resistor, respectively. The other end of the fifth resistor is electrically connected to one end of the thermistor and the second terminal of the second comparison circuit, respectively. The other end of the sixth resistor and the thermistor are both grounded. The third terminal of the second comparison circuit is electrically connected to the power supply. The fourth terminal of the second comparison circuit is electrically connected to the second switching device. The fifth terminal of the second comparison circuit is grounded.

7. The battery charge protection circuit of claim 6, wherein, The second comparator circuit includes a second comparator and a second MOSFET. The first terminal of the second comparator is electrically connected to the other terminal of the fourth resistor, the second terminal of the second comparator is electrically connected to the other terminal of the fifth resistor, the third terminal of the second comparator is electrically connected to the first terminal of the second MOSFET, the fourth terminal of the second comparator is electrically connected to the power supply, the fifth terminal of the second comparator is grounded, the second terminal of the second MOSFET is electrically connected to the second switching device, and the third terminal of the second MOSFET is grounded.

8. The battery charge protection circuit of claim 1, wherein, The overvoltage protection module includes a first overvoltage protection circuit, a second overvoltage protection circuit, and a third overvoltage protection circuit. The first switching device of the first overvoltage protection circuit is electrically connected to the power supply and the first switching device of the first overvoltage protection circuit, respectively. The first switching device of the third overvoltage protection circuit is electrically connected to the first switching device of the second overvoltage protection circuit and the second switching device of the low temperature protection circuit, respectively. The first comparison circuits of the first overvoltage protection circuit, the second overvoltage protection circuit and the third overvoltage protection circuit are respectively electrically connected to the corresponding first switching device.

9. An explosion-proof battery, characterized by Includes the battery charging protection circuit as described in any one of claims 1 to 8.

10. An electronic device, comprising: Includes the battery charging protection circuit as described in any one of claims 1 to 8 or the explosion-proof battery as described in claim 9.

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