Positive end protection detection circuit and battery

Abstract

The utility model provides a positive end protection detection circuit and a battery, the positive end protection detection circuit comprises a switching circuit and a first protection circuit, the first end of the switching circuit is electrically connected with the positive electrode of a battery cell, the second end of the switching circuit is electrically connected with the negative electrode of the battery cell, and the switching circuit is used for controlling the connection state of the whole loop of the first protection circuit; the first protection circuit is connected with the battery cell and the switching circuit, the first protection circuit comprises a fuse and a protection chip, the fuse is located on a main loop of the positive end protection monitoring circuit and electrically connected with the battery cell and the switching circuit, and the first end of the fuse is electrically connected with a voltage detection terminal between terminals of the protection chip; the second end of the fuse is electrically connected with the fuse detection terminal of the protection chip, the third end of the switching circuit is electrically connected with the charging control terminal of the protection chip, and the fourth end of the switching circuit is electrically connected with the discharging control terminal of the protection chip. According to the circuit, the fuse is used for replacing precision resistance sampling, the device cost is greatly reduced, and the PCB layout space is improved.

Description

Technical Field

[0001] The present application relates to the field of polymer batteries, and more specifically, to a positive terminal protection detection circuit and a battery. Background Art

[0002] For voltage sampling in the main circuit of a circuit, the commonly used method is to connect a precision resistor in series to the circuit, detect the voltage difference across the precision resistor, and calculate the current in the circuit based on the resistance value of the precision resistor, so as to take corresponding protective actions.

[0003] However, due to the large size of precision resistors and the fact that they are heat-generating devices, they will occupy a large space on the PCB circuit board, resulting in the size of the PCB protection board being unable to be further reduced. Utility Model Content

[0004] The main purpose of this application is to provide a positive terminal protection detection circuit and a battery to solve the problem that the precision resistors in conventional battery cell protection circuits are large in size, occupy a large PCB circuit board space and cause circuit heating.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a positive terminal protection detection circuit is provided, including a switch circuit, a first protection circuit and a connector; the first end of the switch circuit is electrically connected to the positive pole of the battery cell, and the second end of the switch circuit is electrically connected to the negative pole of the battery cell through the connector, and the switch circuit is used to control the connectivity state of the positive terminal protection detection circuit loop; the first protection circuit is respectively connected to the battery cell, the switch circuit and the connector, and the first protection circuit includes a fuse and a protection chip, the fuse is located on the main circuit of the positive terminal protection monitoring circuit and is respectively electrically connected to the battery cell and the switch circuit, the first end of the fuse is electrically connected to the terminal voltage detection terminal of the protection chip, the second end of the fuse is electrically connected to the fuse detection terminal of the protection chip, the third end of the switch circuit is electrically connected to the charging control terminal of the protection chip, and the fourth end of the switch circuit is electrically connected to the discharge control terminal of the protection chip, and the fuse and the protection chip are both used to perform overcurrent protection on the battery cell.

[0006] Furthermore, the first protection circuit also includes: a first detection module, the first end of the first detection module is electrically connected to the first end of the fuse, and the second end of the first detection module is electrically connected to the inter-terminal voltage detection terminal of the protection chip; a second detection module, the first end of the second detection module is electrically connected to the second end of the fuse, and the second end of the second detection module is electrically connected to the fuse detection terminal of the protection chip.

[0007] Further, the switch circuit further comprises a switch module, a first end of the switch module is electrically connected with the positive electrode of the battery cell, a second end of the switch module is electrically connected with the negative electrode of the battery cell through the connector, a third end of the switch module is electrically connected with the charging control terminal of the protection chip, and a fourth end of the switch module is electrically connected with the discharging control terminal of the protection chip.

[0008] Further, the switch module further comprises a first MOS tube, a source of the first MOS tube is electrically connected with the positive electrode of the battery cell, and a gate of the first MOS tube is electrically connected with the charging control terminal of the protection chip; and a second MOS tube, a source of the second MOS tube is electrically connected with the negative electrode of the battery cell, a gate of the second MOS tube is electrically connected with the discharging control terminal of the protection chip, and a drain of the second MOS tube is electrically connected with a drain of the first MOS tube.

[0009] Further, the first protection circuit further comprises a filter module, a first end of the filter module is electrically connected with the positive electrode of the battery cell and a positive power input terminal of the protection chip respectively, and a second end of the filter module is electrically connected with the negative electrode of the battery cell and a negative power input terminal of the protection chip respectively, and the filter module comprises at least one capacitor connected in series.

[0010] Further, the first protection circuit further comprises a first current limiting module, a first end of the first current limiting module is electrically connected with the positive electrode of the battery cell and a first end of the switch circuit respectively, and a second end of the first current limiting module is electrically connected with the positive power input terminal of the protection chip; and a second current limiting module, a first end of the second current limiting module is electrically connected with the fourth end of the switch circuit, and a second end of the second current limiting module is electrically connected with the discharging control terminal of the protection chip.

[0011] Further, the positive terminal protection detection circuit further comprises a second protection circuit, a first end of the second protection circuit is electrically connected with the second end of the switch circuit, a second end of the second protection circuit is grounded, and the second protection circuit is further electrically connected with the connector.

[0012] Further, the first protection circuit further comprises a third current limiting module, a first end of the third current limiting module is electrically connected with a temperature detection terminal of the protection chip, and a second end of the third current limiting module is electrically connected with a temperature detection terminal of the connector.

[0013] Furthermore, the second protection circuit also includes: a third MOS tube, the source of the third MOS tube is electrically connected to the second end of the switching circuit, and the drain of the third MOS tube is used to input a control signal; a fourth current limiting module, the first end of the fourth current limiting module is electrically connected to the gate of the third MOS tube, and the second end of the fourth current limiting module is grounded; a second capacitor module, the first end of the second capacitor module is electrically connected to the source of the third MOS tube and the positive electrode of the connector respectively, and the second end of the second capacitor module is electrically connected to the second end of the fourth current limiting module.

[0014] Furthermore, the positive end protection detection circuit also includes: a thermistor module, the first end of the thermistor module is electrically connected to the connector, and the second end of the thermistor module is electrically connected to the negative pole of the battery cell; an anti-static module, the first end of the anti-static module is electrically connected to the temperature monitoring terminal of the connector, and the second end of the anti-static module is electrically connected to the negative pole of the battery cell.

[0015] According to one aspect of the present application, a battery is provided, comprising a battery cell and any one of the positive terminal protection detection circuits described above.

[0016] Applying the technical solution of the present application, the positive-end protection detection circuit includes a switch circuit and a first protection circuit. The first end of the switch circuit is electrically connected to the positive electrode of the battery cell, the second end of the switch circuit is electrically connected to the negative electrode of the battery cell, and the switch circuit is used to control the connectivity of the first protection circuit's overall loop. The first protection circuit is connected to the battery cell and the switch circuit, respectively. The first protection circuit includes a fuse and a protection chip. The fuse is located on the main loop of the positive-end protection monitoring circuit and is electrically connected to the battery cell and the switch circuit, respectively. The first end of the fuse is electrically connected to the inter-terminal voltage detection terminal of the protection chip, the second end of the fuse is electrically connected to the fuse detection terminal of the protection chip, the third end of the switch circuit is electrically connected to the charge control terminal of the protection chip, and the fourth end of the switch circuit is electrically connected to the discharge control terminal of the protection chip. Both the fuse and the protection chip are used to provide overcurrent protection for the battery cell. This circuit simplifies the protection circuit by removing the precision resistor in the protection circuit and directly connecting the IC overcurrent sampling line to both ends of the fuse. Its characteristics are direct detection of the voltage across the fuse, removing the precision resistor, and saving PCB layout space. Using fuses instead of precision resistors for sampling greatly reduces device costs and increases PCB layout space, playing a key role in narrowing and shortening the size of PCB protection boards. This solves the problem that the precision resistors in conventional battery protection circuits are large in size, occupying a large PCB circuit board space and causing circuit heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0018] Figure 1 A schematic structural diagram of a positive terminal protection detection circuit provided according to an embodiment of the present application is shown;

[0019] Figure 2 FIG2 shows a structural diagram of another positive terminal protection detection circuit provided according to an embodiment of the present application;

[0020] Figure 3 FIG2 shows a structural diagram of another positive terminal protection detection circuit provided according to an embodiment of the present application;

[0021] Figure 4 FIG2 shows a structural diagram of another positive terminal protection detection circuit provided according to an embodiment of the present application;

[0022] Figure 5 FIG2 shows a structural diagram of another positive terminal protection detection circuit provided according to an embodiment of the present application;

[0023] Figure 6 FIG2 shows a structural diagram of another positive terminal protection detection circuit provided according to an embodiment of the present application;

[0024] Figure 7 A schematic structural diagram of a battery provided according to an embodiment of the present application is shown.

[0025] The above drawings include the following reference numerals:

[0026] 10. Battery cell; 20. Switch circuit; 21. Switch module; 22. First capacitor module; 30. First protection circuit; 31. Fuse; 32. Protection chip; 33. First detection module; 34. Second detection module; 35. Filter module; 36. First current limiting module; 37. Second current limiting module; 38. Third current limiting module; 40. Second protection circuit; 41. Fourth current limiting module; 42. Second capacitor module; 50. Connector; 60. Thermistor module; 70. Anti-static module; Q1. First MOS tube; Q2. Second MOS tube; Q3. Third MOS tube; 100. Positive terminal protection detection circuit. DETAILED DESCRIPTION

[0027] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element or intervening elements may be present. Moreover, in the specification and claims, when it is described that an element is "connected to" another element, the element may be "directly connected to" the other element or "connected to" the other element through a third element.

[0030] For ease of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0031] Integrated Circuit: Integrated Circuit, referred to as IC;

[0032] Printed Circuit Board: Printed Circuit Board, referred to as PCB.

[0033] As introduced in the background technology, the existing voltage sampling method for the main circuit of the circuit is to connect a precision resistor in series to the current loop, detect the voltage difference across the precision resistor, and detect the current in the loop, so as to perform corresponding protection actions. However, due to the large size of the precision resistor and the fact that it is a heat-generating device, it will occupy a large space on the PCB circuit board, resulting in the size of the PCB protection board being unable to be further reduced. In order to solve the problem that the precision resistor in the conventional battery cell protection circuit is large in size, occupies a large space on the PCB circuit board, and causes the circuit to heat up, the present application proposes a positive terminal protection detection circuit and a battery.

[0034] Figure 1 It is a structural diagram of a positive terminal protection detection circuit, such as Figure 1As shown, the positive terminal protection detection circuit includes a switch circuit 20, a first protection circuit 30 and a connector 50; the first end of the switch circuit 20 is electrically connected to the positive electrode of the battery cell 10, and the second end of the switch circuit 20 is electrically connected to the negative electrode of the battery cell 10 through the connector 50. The switch circuit 20 is used to control the connectivity state of the positive terminal protection detection circuit loop; the first protection circuit 30 is respectively connected to the battery cell 10, the switch circuit 20 and the connector 50. The first protection circuit 30 includes a fuse 31 and a protection chip 32. The fuse 31 is located at the positive terminal protection detection circuit. The monitoring circuit is on the main loop and is electrically connected to the battery cell 10 and the switching circuit 20 respectively. The first end of the fuse 31 is electrically connected to the inter-terminal voltage detection terminal of the protection chip 32, the second end of the fuse 31 is electrically connected to the fuse detection terminal of the protection chip 32, the third end of the switching circuit 20 is electrically connected to the charging control terminal of the protection chip 32, and the fourth end of the switching circuit 20 is electrically connected to the discharge control terminal of the protection chip 32. The fuse 31 and the protection chip 32 are both used to perform overcurrent protection on the battery cell 10.

[0035] Among them, Figure 1 As shown, the inter-terminal voltage detection terminal of the protection chip is the VM terminal, the fuse detection terminal of the protection chip is the VINI terminal, the charging control terminal of the protection chip is the CO terminal, and the discharge control terminal of the protection chip is the DO terminal.

[0036] The positive terminal protection detection circuit of the present application includes a switch circuit and a first protection circuit. The first end of the switch circuit is electrically connected to the positive electrode of the battery cell, the second end of the switch circuit is electrically connected to the negative electrode of the battery cell, and the switch circuit is used to control the connectivity state of the entire loop of the first protection circuit; the first protection circuit is respectively connected to the battery cell and the switch circuit. The first protection circuit includes a fuse and a protection chip. The fuse is located on the main circuit of the positive terminal protection monitoring circuit and is respectively electrically connected to the battery cell and the switch circuit. The first end of the fuse is electrically connected to the terminal voltage detection terminal of the protection chip, the second end of the fuse is electrically connected to the fuse detection terminal of the protection chip, the third end of the switch circuit is electrically connected to the charging control terminal of the protection chip, and the fourth end of the switch circuit is electrically connected to the discharge control terminal of the protection chip. The fuse and the protection chip are both used to protect the battery cell from overcurrent. This circuit simplifies the protection circuit, removes the precision resistor in the protection circuit, and directly connects the IC overcurrent sampling line to both ends of the fuse. Its characteristics are direct detection of the voltage across the fuse, removal of the precision resistor, and saving PCB layout space. Using fuses instead of precision resistors for sampling greatly reduces device costs and increases PCB layout space, playing a key role in narrowing and shortening the size of PCB protection boards. This solves the problem that the precision resistors in conventional battery protection circuits are large in size, occupying a large PCB circuit board space and causing circuit heating.

[0037] In some instances, such as Figure 1 and Figure 3 As shown, the first protection circuit 30 further includes: a first detection module 33, a first end of the first detection module 33 is electrically connected to the first end of the fuse 31, and a second end of the first detection module 33 is electrically connected to the inter-terminal voltage detection terminal VM of the protection chip 32; a second detection module 34, a first end of the second detection module 34 is electrically connected to the second end of the fuse 31, and a second end of the second detection module 34 is electrically connected to the fuse detection terminal of the protection chip 32.

[0038] The first and second detection modules are directly connected to the ends of the fuse to detect the voltage difference across the fuse, thereby protecting the battery cells. Compared to traditional precision resistor sampling methods, this reduces PCB size, saves component costs, and improves product reliability. The first and second detection modules detect the voltage difference across the fuse and transmit this voltage difference to the protection chip, which determines whether to protect the battery cells based on the magnitude of the voltage difference. The protection chip is primarily used to protect the circuit. If the protection chip fails and the current in the circuit is excessive, causing the fuse to blow, the fuse will blow to protect the circuit. Furthermore, using the protection chip first to protect the circuit provides instantaneous protection. The protection chip's protection is instantaneous, typically within a few milliseconds or more than ten milliseconds, while a fuse takes longer to blow, typically 1-60 seconds. Therefore, the protection chip provides better protection than a fuse, making it the preferred choice.

[0039] In addition, the installation position of the fuse only needs to be on the main circuit, and the first detection module and the second detection module can be directly connected to the two ends of the fuse.

[0040] The first detection module and the second detection module can be respectively composed of one or more resistors connected in series or in parallel. Figure 4 As shown, the first detection module is composed of a resistor R1, and the second detection module is composed of a resistor R2.

[0041] In some instances, such as Figure 1 and Figure 3As shown, the above-mentioned switching circuit 20 also includes: a switching module 21, a first end of the above-mentioned switching module 21 is electrically connected to the positive electrode of the above-mentioned battery cell 10, a second end of the above-mentioned switching module 21 is electrically connected to the negative electrode of the above-mentioned battery cell 10 through the above-mentioned connector 50, a third end of the above-mentioned switching module 21 is electrically connected to the charging control terminal CO of the above-mentioned protection chip 32, and a fourth end of the above-mentioned switching module 21 is electrically connected to the discharge control terminal DO of the above-mentioned protection chip 32; a first capacitor module 22, a first end of the above-mentioned first capacitor module 22 is electrically connected to the first end of the above-mentioned switch module 21, and a second end of the above-mentioned first capacitor module 22 is electrically connected to the second end of the above-mentioned switch module 21.

[0042] The protection chip of the first protection circuit pre-stores a mapping table between battery cell temperature and charging overcurrent detection voltage, which shows the corresponding relationship between battery cell temperature and charging overcurrent detection voltage. While monitoring the battery cell temperature, the first protection circuit sets a corresponding charging overcurrent detection voltage based on the battery cell temperature in real time, assuming it is a first charging overcurrent detection voltage. Simultaneously, it monitors the current charging overcurrent detection voltage of the charging circuit, assuming it is a second charging overcurrent detection voltage. The protection chip of the first protection circuit compares the first and second charging overcurrent detection voltages in real time. If the first charging overcurrent detection voltage is greater than the second charging overcurrent detection voltage, it indicates that the positive terminal protection detection circuit is currently functioning properly. If the first charging overcurrent detection voltage is less than the second charging overcurrent detection voltage, it indicates that the current maximum current in the charging circuit has reached or exceeded the charging overcurrent value range set by the protection chip. The first protection circuit then controls the switch circuit to disconnect, disconnecting the battery cell from the connector and stopping charging.

[0043] The first capacitor module is used for filtering, such as Figure 4 As shown, the first capacitor module is composed of capacitor C1.

[0044] In some instances, such as Figure 4 As shown, the switch module 21 further includes: a first MOS transistor Q1, wherein the source of the first MOS transistor Q1 is electrically connected to the positive electrode of the battery cell 10, and the gate of the first MOS transistor Q1 is electrically connected to the charge control terminal CO of the protection chip 32; a second MOS transistor Q2, wherein the source of the second MOS transistor Q2 is electrically connected to the negative electrode of the battery cell 10, the gate of the second MOS transistor Q2 is electrically connected to the discharge control terminal DO of the protection chip 32, and the drain of the second MOS transistor Q2 is electrically connected to the drain of the first MOS transistor Q1.

[0045] in, Figure 4The first MOS transistor Q1 and the second MOS transistor Q2 are both NMOS transistors. In some embodiments, the first MOS transistor Q1 and the second MOS transistor Q2 can also be PMOS transistors. The first MOS transistor Q1 and the second MOS transistor Q2 are used to turn on or off in response to a signal provided by the protection chip to protect the battery cell.

[0046] In some instances, such as Figure 3 As shown, the first protection circuit 30 further includes: a filter module 35, the first end of the filter module 35 being electrically connected to the positive electrode of the battery cell 10 and the positive power input terminal of the protection chip 32, respectively; the second end of the filter module 35 being electrically connected to the negative electrode of the battery cell 10 and the negative power input terminal of the protection chip 32, respectively; and the filter module 35 including at least one capacitor connected in series.

[0047] During the charging process, the filter module can prevent voltage fluctuations in the positive terminal protection detection circuit, keeping the circuit voltage stable. If the filter module is composed of multiple capacitors connected in series, it can prevent one of the capacitors from failing. That is, if one of the capacitors in the filter module fails, the other capacitors are used to stabilize the voltage fluctuations in the circuit to protect the circuit.

[0048] like Figure 4 As shown in FIG, the filtering module is composed of two capacitors C.

[0049] In some instances, such as Figure 3 As shown, the above-mentioned first protection circuit 30 also includes: a first current limiting module 36, the first end of the above-mentioned first current limiting module 36 is electrically connected to the positive electrode of the above-mentioned battery cell 10 and the first end of the above-mentioned switching circuit 20, respectively, and the second end of the above-mentioned first current limiting module 36 is electrically connected to the positive power input end of the above-mentioned protection chip 32; a second current limiting module 37, the first end of the above-mentioned second current limiting module 37 is electrically connected to the fourth end of the above-mentioned switching circuit 20, and the second end of the above-mentioned second current limiting module 37 is electrically connected to the discharge control terminal DO of the above-mentioned protection chip 32.

[0050] Wherein, the first current limiting module and the second current limiting module are both used to limit the current in the circuit, and the first current limiting module and the second current limiting module are both composed of one or more resistors connected in series or in parallel. Figure 4 As shown, the first current limiting module is composed of a resistor R3, and the second current limiting module is composed of a resistor R4.

[0051] In some instances, such as Figure 2 As shown, the positive end protection detection circuit further includes: a second protection circuit 40, a first end of the second protection circuit 40 is electrically connected to the second end of the switch circuit 20, a second end of the second protection circuit 40 is grounded, and the second protection circuit 40 is also electrically connected to the connector 50.

[0052] The switch circuit is connected to a connector and, through the connector, to a circuit board in an external device, such as a mobile phone or tablet, thereby controlling the connectivity between the battery cell and the circuit board. The second protection circuit is used to protect against backlash in the circuit. In the event of backlash, the second protection circuit can control the switch circuit to disconnect, thereby protecting the circuit.

[0053] In some instances, such as Figure 3 As shown, the first protection circuit 30 further includes: a third current limiting module 38, a first end of the third current limiting module 38 is electrically connected to the temperature detection terminal CIL of the protection chip 32, and a second end of the third current limiting module 38 is electrically connected to the temperature detection terminal CIL of the connector 50.

[0054] The third current limiting module is used to limit the current of the circuit. The third current limiting module is composed of one or more resistors connected in series or in parallel. Figure 4 As shown, the third current limiting module is composed of a resistor R5.

[0055] In some instances, such as Figure 3 As shown, the second protection circuit 40 further includes: a third MOS transistor Q3, wherein the source of the third MOS transistor Q3 is electrically connected to the second end of the switch circuit 20, and the drain of the third MOS transistor Q3 is used to input a control signal; a fourth current limiting module 41, wherein a first end of the fourth current limiting module 41 is electrically connected to the gate of the third MOS transistor Q3, and a second end of the fourth current limiting module 41 is grounded; and a second capacitor module 42, wherein a first end of the second capacitor module 42 is electrically connected to the source of the third MOS transistor Q3 and the positive electrode of the connector 50, respectively, and a second end of the second capacitor module 42 is electrically connected to the second end of the fourth current limiting module 41.

[0056] The third MOS transistor Q3 can be an NMOS or a PMOS. Figure 4 The third MOS tube Q3 is an NMOS. The fourth current limiting module can be composed of one or more resistors connected in series or in parallel, such as Figure 4 As shown, Figure 4 The fourth current limiting module is composed of a resistor R6, and the second capacitor module can be composed of one or more capacitors, such as Figure 4 As shown, the second capacitor module is composed of capacitor C4.

[0057] Among them, such as Figure 4As shown, in the case of a backlash in the circuit, that is, the positive terminal B+ of the battery cell is connected to a negative voltage, and the negative terminal B- of the battery cell is connected to a positive voltage. At this time, the positive terminal P+ of the connector is a negative voltage, which is less than the ground voltage. The third MOS transistor Q3 is an NMOS, and the gate voltage of the third MOS transistor Q3 is greater than the source voltage of the third MOS transistor Q3. The third MOS transistor Q3 is turned on, and the DO signal of the drain of the third MOS transistor Q3 is transmitted to the second end of the first protection circuit (that is, the source of the second MOS transistor Q2). At this time, the source signal of the second MOS transistor Q2 is the DO signal, and the gate signal of the second MOS transistor Q2 is the DO signal. Therefore, the second MOS transistor Q2 is turned off, thereby achieving backlash protection for the circuit.

[0058] In some instances, such as Figure 3 As shown, the positive end protection detection circuit further includes: a thermistor module 60, a first end of the thermistor module 60 is electrically connected to the connector 50, and a second end of the thermistor module 60 is electrically connected to the negative electrode of the battery cell 10; an anti-static module 70, a first end of the anti-static module 70 is electrically connected to the temperature monitoring terminal of the connector 50, and a second end of the anti-static module 70 is electrically connected to the negative electrode of the battery cell 10.

[0059] Among them, such as Figure 5 and Figure 6 As shown, the fuse 31 can be set at any position in the main circuit, and it is only necessary to control the first detection module and the second detection module to be connected to the two ends of the fuse.

[0060] Among them, the thermistor module is used to detect the core temperature of the battery cell and feed the core temperature back to the protection chip, thereby realizing the monitoring of the core temperature of the battery cell, and the anti-static module is used to provide anti-static protection for the circuit. Figure 4 As shown, the thermistor module is composed of thermistor R7, and the anti-static module is composed of a bidirectional transient suppression diode D.

[0061] The above embodiment simplifies the protection circuit by removing the precision resistors and connecting the IC overcurrent sensing line directly to the fuse terminals. This feature directly detects the voltage across the fuse, eliminating the precision resistors and saving PCB layout space. Using fuses instead of precision resistors for sampling significantly reduces component costs and increases PCB layout space, playing a key role in narrowing and shortening the size of the PCB protection board.

[0062] The embodiment of the present application also provides a battery, such as Figure 7 As shown, the battery includes a battery cell 10 and any one of the above-mentioned positive terminal protection detection circuits 100 .

[0063] The above-mentioned battery of the present application uses a fuse instead of a precision resistor for sampling, which greatly reduces the device cost and increases the PCB layout space, and plays a key role in narrowing and shortening the size of the PCB protection board.

[0064] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0065] The positive terminal protection detection circuit of the present application includes a switch circuit and a first protection circuit. The first end of the switch circuit is electrically connected to the positive electrode of the battery cell, the second end of the switch circuit is electrically connected to the negative electrode of the battery cell, and the switch circuit is used to control the connectivity state of the entire loop of the first protection circuit; the first protection circuit is respectively connected to the battery cell and the switch circuit. The first protection circuit includes a fuse and a protection chip. The fuse is located on the main circuit of the positive terminal protection monitoring circuit and is respectively electrically connected to the battery cell and the switch circuit. The first end of the fuse is electrically connected to the terminal voltage detection terminal of the protection chip, the second end of the fuse is electrically connected to the fuse detection terminal of the protection chip, the third end of the switch circuit is electrically connected to the charging control terminal of the protection chip, and the fourth end of the switch circuit is electrically connected to the discharge control terminal of the protection chip. The fuse and the protection chip are both used to protect the battery cell from overcurrent. This circuit simplifies the protection circuit, removes the precision resistor in the protection circuit, and directly connects the IC overcurrent sampling line to both ends of the fuse. Its characteristics are direct detection of the voltage across the fuse, removal of the precision resistor, and saving PCB layout space. Using fuses instead of precision resistors for sampling greatly reduces device costs and increases PCB layout space, playing a key role in narrowing and shortening the size of PCB protection boards. This solves the problem that the precision resistors in conventional battery protection circuits are large in size, occupying a large PCB circuit board space and causing circuit heating.

[0066] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A positive terminal protection detection circuit, characterized in that: including a switch circuit, a first protection circuit and a connector; The first end of the switch circuit is electrically connected to the positive electrode of the battery cell, and the second end of the switch circuit is electrically connected to the negative electrode of the battery cell through a connector, and the switch circuit is used to control the connectivity state of the positive terminal protection detection circuit loop; The first protection circuit is respectively connected to the battery cell, the switching circuit and the connector. The first protection circuit includes a fuse and a protection chip. The fuse is located on the main loop of the positive end protection monitoring circuit and is respectively electrically connected to the battery cell and the switching circuit. The first end of the fuse is electrically connected to the inter-terminal voltage detection terminal of the protection chip, the second end of the fuse is electrically connected to the fuse detection terminal of the protection chip, the third end of the switching circuit is electrically connected to the charging control terminal of the protection chip, and the fourth end of the switching circuit is electrically connected to the discharge control terminal of the protection chip. The fuse and the protection chip are both used to perform overcurrent protection on the battery cell.

2. The positive terminal protection detection circuit according to claim 1, characterized in that: The first protection circuit further includes: a first detection module, wherein a first end of the first detection module is electrically connected to the first end of the fuse, and a second end of the first detection module is electrically connected to the inter-terminal voltage detection terminal of the protection chip; A second detection module, wherein a first end of the second detection module is electrically connected to the second end of the fuse, and a second end of the second detection module is electrically connected to the fuse detection terminal of the protection chip.

3. The positive terminal protection detection circuit according to claim 1, characterized in that: The switching circuit further includes: a switch module, wherein a first end of the switch module is electrically connected to the positive electrode of the battery cell, a second end of the switch module is electrically connected to the negative electrode of the battery cell through the connector, a third end of the switch module is electrically connected to the charge control terminal of the protection chip, and a fourth end of the switch module is electrically connected to the discharge control terminal of the protection chip; A first capacitor module, wherein a first end of the first capacitor module is electrically connected to the first end of the switch module, and a second end of the first capacitor module is electrically connected to the second end of the switch module.

4. The positive terminal protection detection circuit according to claim 3, characterized in that: The switch module further includes: a first MOS transistor, wherein a source electrode of the first MOS transistor is electrically connected to the positive electrode of the battery cell, and a gate electrode of the first MOS transistor is electrically connected to the charging control terminal of the protection chip; a second MOS transistor, wherein the source of the second MOS transistor is electrically connected to the negative electrode of the battery cell, the gate of the second MOS transistor is electrically connected to the discharge control terminal of the protection chip, and the drain of the second MOS transistor is electrically connected to the drain of the first MOS transistor.

5. The positive terminal protection detection circuit according to claim 1, characterized in that: The first protection circuit further includes: A filter module, wherein the first end of the filter module is electrically connected to the positive electrode of the battery cell and the positive power input terminal of the protection chip, respectively, and the second end of the filter module is electrically connected to the negative electrode of the battery cell and the negative power input terminal of the protection chip, respectively, and the filter module includes at least one capacitor connected in series.

6. The positive terminal protection detection circuit according to claim 1, characterized in that: The first protection circuit further includes: a first current limiting module, wherein a first end of the first current limiting module is electrically connected to the positive electrode of the battery cell and the first end of the switch circuit, respectively, and a second end of the first current limiting module is electrically connected to the positive power input terminal of the protection chip; A second current limiting module, wherein a first end of the second current limiting module is electrically connected to the fourth end of the switch circuit, and a second end of the second current limiting module is electrically connected to the discharge control terminal of the protection chip.

7. The positive terminal protection detection circuit according to claim 1, characterized in that: The positive terminal protection detection circuit further includes: A second protection circuit, wherein a first end of the second protection circuit is electrically connected to the second end of the switch circuit, a second end of the second protection circuit is grounded, and the second protection circuit is also electrically connected to the connector.

8. The positive terminal protection detection circuit according to claim 1, characterized in that: The first protection circuit further includes: A third current limiting module, wherein a first end of the third current limiting module is electrically connected to the temperature detection terminal of the protection chip, and a second end of the third current limiting module is electrically connected to the temperature detection terminal of the connector.

9. The positive terminal protection detection circuit according to claim 7, characterized in that: The second protection circuit further includes: a third MOS transistor, wherein a source of the third MOS transistor is electrically connected to the second end of the switch circuit, and a drain of the third MOS transistor is used to input a control signal; a fourth current limiting module, wherein a first end of the fourth current limiting module is electrically connected to the gate of the third MOS transistor, and a second end of the fourth current limiting module is grounded; A second capacitor module, wherein a first end of the second capacitor module is electrically connected to the source of the third MOS tube and the positive electrode of the connector respectively, and a second end of the second capacitor module is electrically connected to the second end of the fourth current limiting module.

10. The positive terminal protection detection circuit according to claim 7, characterized in that: The positive terminal protection detection circuit further includes: a thermistor module, wherein a first end of the thermistor module is electrically connected to the connector, and a second end of the thermistor module is electrically connected to the negative electrode of the battery cell; An anti-static module, wherein a first end of the anti-static module is electrically connected to the temperature monitoring terminal of the connector, and a second end of the anti-static module is electrically connected to the negative electrode of the battery cell.

11. A battery, characterized in that: The invention comprises a battery cell and the positive terminal protection detection circuit according to any one of claims 1 to 10.

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