A battery protection circuit and battery protection board

Abstract

The application relates to a battery protection circuit and a battery protection board, relating to the technical field of batteries. The circuit comprises a device connection end, a telecommunication connection end, a battery charging and discharging protection module and a switch module. The device connection end comprises a positive device connection end and a negative device connection end; the battery core connection end comprises a positive battery core connection end and a negative battery core connection end. The first end of the battery charging and discharging protection module is connected to the negative device connection end, and the second end of the battery charging and discharging protection module is used for connecting the negative battery core connection end. The first end of the switch module is used for connecting the positive device connection end and the positive battery core connection end, the second end of the switch module is connected to the third end of the battery charging and discharging protection module; a removable electric insulator is arranged between the first end of the switch module and the second end of the switch module, the removable electric insulator can be removed when the battery is correctly connected, so that the switch module is closed, and the battery charging and discharging protection module is turned on.

Description

Technical Field

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

[0002] With the widespread use of portable electronic devices, rechargeable batteries are typically installed inside these devices and electrically connected to the motherboard via connectors. Most existing devices use board-to-board (BTB) connectors for electrical connection to the motherboard. The structure consists of a male BTB connector on the battery side and a female BTB connector on the motherboard side. The connection between the battery and the motherboard is achieved through manual snap-fit ​​or tooling insertion.

[0003] However, BTB connectors typically have exposed metal contacts, and the battery's positive, negative, and other signal terminals are compactly arranged within the connector. During actual production and assembly, especially at the moment of manual snap-fitting of the BTB male and female connectors, a positional misalignment may occur between the male and female contacts, causing the battery's positive terminal to briefly contact the negative terminal or other signal terminals. Since rechargeable batteries are high-current power supply devices—for example, lithium batteries commonly used in smartphones can output tens of amperes of current instantaneously—if such a short circuit occurs at the moment of snap-fitting, it can easily damage motherboard components, activate battery protection circuits, or even burn out the circuitry.

[0004] Existing technologies generally lack structural protection against the risk of short circuits during the BTB connection process of built-in batteries, which means that there is still a risk of damage to the motherboard or battery due to momentary short circuits in the battery during actual production. Utility Model Content

[0005] This application provides a protection circuit for protecting the circuit during the battery connection process of a board-to-board connector and a battery protection board equipped with the circuit.

[0006] According to one aspect of this application, one embodiment provides a battery protection circuit, comprising:

[0007] The device connection terminal includes a positive device connection terminal and a negative device connection terminal;

[0008] The cell connection terminal includes a positive cell connection terminal and a negative cell connection terminal;

[0009] A battery charge / discharge protection module, wherein the first end of the battery charge / discharge protection module is connected to the negative electrode device connection terminal, and the second end of the battery charge / discharge protection module is used to connect to the negative electrode cell connection terminal;

[0010] A switch module, wherein a first end of the switch module is used to connect the positive electrode connection terminal and the positive electrode cell connection terminal, and a second end of the switch module is connected to the third end of the battery charge / discharge protection module; a removable electrical insulator is provided between the first end and the second end of the switch module, and the removable electrical insulator can be removed when the battery is correctly snapped on, so that the switch module is closed and the battery charge / discharge protection module is turned on.

[0011] In one embodiment, the battery charge / discharge protection module includes:

[0012] A current detection module, wherein the first end of the current detection module is connected to the third end of the battery charge and discharge protection module, and the second end of the current detection module is connected to the first end of the battery charge and discharge protection module.

[0013] A charge / discharge switching module, wherein a first end of the charge / discharge switching module is connected to a first end of the battery charge / discharge protection module, and a second end of the charge / discharge switching module is connected to a second end of the battery charge / discharge protection module;

[0014] The current detection module is used to close the charge / discharge switching module when the removable electrical insulator is removed, so as to activate the battery charge / discharge protection module.

[0015] In one embodiment, the current detection module includes a current detection chip and a resistor R4;

[0016] The current detection chip includes a power input terminal, a power ground terminal, and a charge / discharge detection terminal;

[0017] The power input terminal of the current detection chip is connected to the first terminal of the current detection module, the power ground terminal of the current detection chip is connected to the second terminal of the battery charge and discharge protection module, the charge and discharge detection terminal of the current detection chip is connected to the first terminal of resistor R4, and the second terminal of resistor R4 is connected to the second terminal of the current detection module.

[0018] In one embodiment, the charge / discharge switching module includes a bidirectional series switch transistor, resistors R1 and R3, capacitors C2 and C3; the current detection chip further includes a discharge control terminal and a charge control terminal.

[0019] The first end of the bidirectional series switch is connected to the first end of the charge / discharge switching module, the second end of the bidirectional series switch is connected to the second end of the charge / discharge switching module, the first control end of the bidirectional series switch is connected to the first end of the resistor R1, the second end of the resistor R1 is connected to the discharge control end, the second control end of the bidirectional series switch is connected to the first end of the resistor R3, the second end of the resistor R3 is connected to the charging control end, the first end of the bidirectional series switch is also connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the first end of the capacitor C3, and the second end of the capacitor C3 is connected to the second end of the bidirectional series switch.

[0020] In one embodiment, the battery protection circuit further includes a filter capacitor C1, the first end of which is connected to the positive electrode cell connection terminal, and the second end of which is connected to the negative electrode cell connection terminal.

[0021] In one embodiment, the battery protection circuit further includes a sampling resistor R11 and a battery parameter acquisition module;

[0022] The first end of the sampling resistor R11 is connected to the negative electrode cell connection terminal, and the second end of the sampling resistor R11 is connected to the second terminal of the battery charge and discharge protection module.

[0023] The first sampling terminal of the battery parameter acquisition module is connected to the first terminal of the resistor R11, and the second sampling terminal of the battery parameter acquisition module is connected to the second terminal of the resistor R11; the battery parameter acquisition module is used to acquire the operating current of the battery through the sampling resistor R11.

[0024] In one embodiment, the battery parameter acquisition module includes a battery parameter acquisition chip, a current-limiting resistor R10, and a filtering module;

[0025] The battery parameter acquisition chip includes a first voltage input terminal and a ground terminal;

[0026] The first end of the current-limiting resistor R10 is connected to the positive electrode cell connection terminal, and the second end of the current-limiting resistor R10 is connected to the first voltage input terminal.

[0027] The first end of the filter module is connected to the second end of the current-limiting resistor R10, and the second end of the filter module is connected to the ground terminal.

[0028] In one embodiment, the battery parameter acquisition module further includes a thermistor RT10 and a capacitor C42, and the battery parameter acquisition chip further includes a second voltage input terminal and a thermistor voltage detection terminal; the first terminal of the thermistor RT10 is connected to the second voltage input terminal, and the second terminal of the thermistor RT10 is connected to the thermistor voltage detection terminal; the first terminal of the capacitor C42 is connected to the first terminal of the thermistor RT10, and the second terminal of the capacitor C42 is connected to the second terminal of the thermistor RT10.

[0029] In one embodiment, one of the first end and the second end of the switch module is an elastic conductor, and the other is a metallic conductor; when the removable electrical insulator is located between the first end and the second end of the switch module, the elastic conductor has an elastic restoring force; when the removable electrical insulator is removed, the elastic conductor, under the action of the elastic restoring force, connects the first end and the second end of the switch module.

[0030] According to one aspect of this application, one embodiment provides a battery protection board, including the battery protection circuit described in any of the above embodiments.

[0031] According to the battery protection circuit and battery protection board of the above embodiments, the battery protection circuit includes a device connection terminal, a cell connection terminal, a battery charge / discharge protection module, and a switch module. By providing a switch module with a removable insulator between the device connection terminal and the cell connection terminal, and cooperating with the battery charge / discharge protection module, the battery can only perform normal charging and discharging when the connection is correctly completed. This avoids problems such as accidental power-on, breakdown, electrostatic damage, or malfunction of the protection chip caused by unstable momentary contact during board-to-board connector engagement, thus improving the safety of the board-to-board connector and the safety during battery use. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the battery protection circuit in one embodiment. Figure 1 ;

[0033] Figure 2 This is a schematic diagram of the battery protection circuit in one embodiment. Figure 2 ;

[0034] Figure 3 This is a circuit diagram of a battery protection circuit in one embodiment;

[0035] Figure 4 This is a schematic diagram of the switch module in one embodiment;

[0036] Figure 5This is a schematic diagram of the battery protection board in another embodiment. Detailed Implementation

[0037] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0038] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments, and the operational steps involved in each embodiment can also be rearranged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the specification and drawings are only for clearly describing a particular embodiment and do not imply that they represent the necessary components and / or order.

[0039] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0040] Please refer to Figure 1 One embodiment provides a battery protection circuit 100, including a device connection terminal 110, a cell connection terminal 120, a battery charge and discharge protection module 130, and a switch module 140.

[0041] In one embodiment, the device connection terminal 110 includes a positive device connection terminal 111 and a negative device connection terminal 112, for connecting to the power input terminal of the electronic device motherboard.

[0042] In one embodiment, the cell connection terminal 120 includes a positive cell connection terminal 121 and a negative cell connection terminal 122 for connecting to the positive and negative terminals of the battery cell.

[0043] In one embodiment, to prevent momentary short circuits during the battery connection process (i.e., the insertion process between the battery BTB connector and the motherboard BTB connector), this application includes a battery charge / discharge protection module 130 in the battery protection circuit 100. The first end of the battery charge / discharge protection module 130 is connected to the negative terminal device connection terminal 112, and the second end of the battery charge / discharge protection module 130 is connected to the negative terminal cell connection terminal 122. This module performs battery charging protection, discharging protection, and short-circuit protection in the negative terminal circuit, ensuring the safe switching of the battery negative terminal branch.

[0044] In one embodiment, to further ensure that no instantaneous current is generated during battery connection, this application also includes a switch module 140 in the battery protection circuit 100. The first terminal of the switch module 140 is connected to both the positive device connection terminal 111 and the positive cell connection terminal 121, and the second terminal of the switch module 140 is connected to the third terminal of the battery charge / discharge protection module 130. The switch module 140 can be an NMOS, PMOS, dual-transistor integrated MOS, or a mechanical switch structure. In this application, the switch module 140 is a mechanical switch structure, and a removable electrical insulator is provided between the first terminal and the second terminal of the switch module 140.

[0045] In one embodiment, the electrical insulator can be a plastic sheet, an insulating sheet, or a separating pull tab, etc. It is in the inserted state before the battery is fully snapped together, blocking the electrical connection between the first and second ends of the switch module 140, so that the battery charge and discharge protection module 130 cannot be turned on. Then the device connection end 110 and the cell connection end 120 cannot form a circuit, thus preventing the battery from outputting voltage to the device end during the snapping process.

[0046] In one embodiment, after the battery is snapped in, the removable electrical insulator is pulled out or automatically removed by the structure, causing the switch module 140 to close, connecting the first and second ends of the switch module 140, thereby enabling the circuit connection between the device connection end 110 and the cell connection end 120, so that the battery can normally supply power to the electronic device and can perform normal charging and discharging control.

[0047] In summary, when operators connect the battery BTB connector during the production process, the presence of the electrical insulator prevents any form of instantaneous short circuit or accidental contact between the positive and negative terminals of the battery. This effectively prevents problems such as motherboard damage, battery protection device burnout, or abnormal cell overcurrent caused by instantaneous overcurrent.

[0048] Please refer to Figure 2 In one embodiment, the battery charge / discharge protection module 130 includes a current detection module 131 and a charge / discharge switching module 132.

[0049] In one embodiment, the first terminal of the current detection module 131 is connected to the third terminal of the battery charge / discharge protection module 130, and the second terminal of the current detection module 131 is connected to the first terminal of the battery charge / discharge protection module 130. The current detection module 131 determines whether the current charging current and discharging current of the battery are within a set range by detecting the voltage difference between the first terminal and the second terminal. When the current circuit is detected to be in a safe state, the current detection module 131 outputs a control signal to the charge / discharge switching module 132 to make the charge / discharge switching module 132 in a conducting state; when an abnormal current is detected, the current detection module 131 pulls the control signal low to turn off the charge / discharge switching module 132, thereby disconnecting the battery circuit.

[0050] In one embodiment, the first end of the charge / discharge switching module 132 is connected to the first end of the battery charge / discharge protection module 130, and the second end of the charge / discharge switching module is connected to the second end of the battery charge / discharge protection module 130. When the battery is not yet connected, a removable electrical insulator is inserted between the first and second ends of the switching module 140, preventing the current detection module 131 from obtaining the battery terminal voltage, thus placing it in an unpowered or inactive state, and keeping the charge / discharge switching module 132 off. When the battery is connected, the removable electrical insulator is removed, putting the switching module 140 in a conductive state, allowing the current detection module 131 to receive power from the battery. After power-on, the current detection module 131 detects the negative or positive current and outputs a control signal to turn on the charge / discharge switching module 132, thereby activating the entire battery charge / discharge protection module 130 and enabling normal output from the battery cell.

[0051] Please refer to Figure 3 In one embodiment, the current detection module 131 includes a CM1006 current detection chip (i.e., Figure 3 The CM1006 current detection chip includes a power input terminal, a power ground terminal, and a charge / discharge detection terminal. The chip is configured to detect the current changes of the battery in real time during charging and discharging, and use the detection results to control the working state of the charge / discharge switching module 132.

[0052] In one embodiment, the power input terminal of the CM1006 current sensing chip (i.e. Figure 3 The VDD pin of chip U1 in the CM1006 current sensing chip is electrically connected to the first terminal of current sensing module 131 to obtain operating power from the battery circuit. The power ground terminal of the CM1006 current sensing chip is connected to the second terminal of battery charge / discharge protection module 130, enabling the CM1006 current sensing chip to obtain a stable reference ground potential. The charge / discharge detection terminal of the CM1006 current sensing chip (i.e., Figure 3The VM pin of chip U1 is electrically connected to the first end of resistor R4, and the second end of resistor R4 is connected to the second end of current detection module 131. Resistor R4 serves as a current sampling resistor, used to convert the current passing through the battery circuit into a differential voltage signal, enabling the CM1006 current detection chip to accurately determine whether the battery is currently charging or discharging based on this differential voltage, and to determine the magnitude changes of the charging and discharging currents.

[0053] It should be noted that the CM1006 current detection chip continuously monitors the voltage changes at its charge / discharge detection terminal. When the user correctly connects the battery to the device and the removable electrical insulator is removed, the battery charge / discharge protection module 130 is turned on, and the current detection module 131 immediately enters the working state. At this time, the CM1006 current detection chip can quickly confirm whether the circuit is under normal operating conditions by detecting the voltage difference across the resistor R4, and outputs a control signal after confirming that the current signal is stable, causing the charge / discharge switching switch module 132 in the battery charge / discharge protection module 130 to close, thereby completing the conduction operation between the battery cell and the device.

[0054] In one embodiment, to ensure normal power supply to the power input terminal of the CM1006 current detection chip, a connection is made between the first terminal of the switching module 140 and the positive device connection terminal 111 (i.e., ...). Figure 3 The + terminal and the positive cell connection terminal 121 (i.e. Figure 3 A resistor R2 is provided between the BAT+ terminals to provide power protection for the CM1006 current sensing chip.

[0055] Please refer to Figure 3 In one embodiment, the charge / discharge switching module 132 includes a bidirectional series switch D1, a resistor R1, a resistor R3, a capacitor C2, and a capacitor C3.

[0056] In one embodiment, the bidirectional series switch D1 can be composed of two N-MOS transistors connected in reverse series to achieve bidirectional on / off control of the battery charging and discharging paths. The first terminal of the bidirectional series switch D1 is connected to the first terminal of the charge / discharge switching module 132, and the second terminal of the bidirectional series switch D1 is connected to the second terminal of the charge / discharge switching module 132. To make the gate drive of the bidirectional series switch D1 more stable, the first control terminal of the bidirectional series switch D1 is connected to the first terminal of resistor R1, and the second terminal of resistor R1 is connected to the discharge control terminal of the current detection chip (i.e.,...). Figure 3 The DO pin of chip U1 allows the current sensing chip to apply a discharge direction drive signal to the corresponding switch control terminal through resistor R1. Similarly, the second control terminal of the bidirectional series switch D1 is connected to the first terminal of resistor R3, and the second terminal of resistor R3 is connected to the charging control terminal of the current sensing chip (i.e., the charging control terminal of the current sensing chip). Figure 3 The CO pin of chip U1 enables the current detection chip to control the charging direction switch.

[0057] In one embodiment, to further improve the stability of the bidirectional series switch D1 during the turn-on and turn-off processes, the first terminal of the bidirectional series switch D1 is also connected to the first terminal of capacitor C2, the second terminal of capacitor C2 is connected to the first terminal of capacitor C3, and the second terminal of capacitor C3 is connected to the second terminal of the bidirectional series switch D1. Capacitors C2 and C3 together form a filter network across the two ends of the switch, which can absorb transient voltage spikes generated by switching operations and filter out high-frequency interference in the control signal link, preventing the MOSFET from falsely turning on or off.

[0058] Please refer to Figure 3 In one embodiment, the battery protection circuit 100 provided in this application further includes a filter capacitor C1, used to regulate and filter the voltage generated between the positive electrode cell connection terminal 121 and the negative electrode cell connection terminal 122, so as to suppress voltage fluctuations generated by the battery during charging, discharging or switching. Specifically, the first end of the filter capacitor C1 is connected to the positive electrode cell connection terminal 121, and the second end of the filter capacitor C1 is connected to the negative electrode cell connection terminal 122.

[0059] Please refer to Figure 3 In one embodiment, the battery protection circuit 100 of this application further includes a sampling resistor R11 and a battery parameter acquisition module 150.

[0060] In one embodiment, the first end of the sampling resistor R11 is connected to the negative electrode cell connection terminal 122, and the second end of the sampling resistor R11 is connected to the second terminal of the battery charge / discharge protection module 130. Connecting the sampling resistor R11 in series between the negative electrode cell connection terminal 122 and the battery charge / discharge protection module 130 ensures that when the battery is charging or discharging, the operating current flowing through the battery will synchronously flow through the sampling resistor R11, generating a sampling voltage proportional to the current magnitude across the sampling resistor R11.

[0061] In one embodiment, the battery parameter acquisition module 150 is provided with a first sampling terminal and a second sampling terminal. The first sampling terminal of the battery parameter acquisition module 150 is connected to the first terminal of the resistor R11, and the second sampling terminal of the battery parameter acquisition module 150 is connected to the second terminal of the resistor R11. The battery parameter acquisition module 150 calculates the operating current flowing through the battery by detecting the voltage difference across the sampling resistor R11, and outputs the operating current to the electronic device.

[0062] In one embodiment, in order to achieve accurate monitoring of battery status, the battery parameter acquisition module 150 includes a battery parameter acquisition chip, a current limiting resistor R10, and a filtering module.

[0063] In one embodiment, the battery parameter acquisition chip uses the bq27542DRZ-G1 chip (i.e. Figure 3 The chip U14 integrates battery information acquisition functions such as voltage detection, coulomb measurement, battery health assessment, and temperature detection. This battery parameter acquisition chip has a first voltage input terminal... Figure 3 The REGIN pin of chip U14 and the ground terminal (i.e. Figure 3 (VSS pin of chip U14 in the chip).

[0064] In one embodiment, the first end of the current-limiting resistor R10 is connected to the positive electrode cell connection terminal 121, and the second end of the current-limiting resistor R10 is connected to the first voltage input terminal. The current-limiting resistor R10 can limit the input voltage flowing to the battery parameter acquisition chip, preventing transient fluctuations or external interference from impacting the first voltage input terminal of the chip.

[0065] In one embodiment, the first terminal of the filtering module is connected to the second terminal of the current-limiting resistor R10, and the second terminal of the filtering module is connected to the ground terminal. Specifically, the filtering module includes capacitors C10 and C11. The first terminal of capacitor C10 is connected to the first terminal of the filtering module, and the second terminal of capacitor C10 is connected to the second terminal of the filtering module. The first terminal of capacitor C11 is connected to the first terminal of the filtering module, and the second terminal of capacitor C11 is connected to the second terminal of the filtering module. This filtering module can smooth the voltage signal input to the battery parameter acquisition chip, ensuring that the chip's first voltage sampling terminal obtains a stable battery voltage signal.

[0066] In one embodiment, the battery parameter acquisition module 150 further includes a thermistor RT10 and a capacitor C42 for detecting the battery temperature. In addition to the first voltage input terminal, the battery parameter acquisition chip also includes a second voltage input terminal (i.e., Figure 3 The REG25 pin of chip U14 and the thermistor voltage detection terminal (i.e. Figure 3 (TS pin of chip U14 in the chip).

[0067] In one embodiment, the first terminal of the thermistor RT10 is connected to the second voltage input terminal, and the second terminal of the thermistor RT10 is connected to the thermistor voltage detection terminal. The thermistor RT10 can be a negative temperature coefficient thermistor, which can change its resistance with temperature, thereby enabling the battery parameter acquisition chip to calculate the real-time temperature of the battery based on the voltage change across the thermistor RT10.

[0068] In one embodiment, to improve the stability of the temperature detection signal, the first end of capacitor C42 is connected to the first end of the thermistor RT10, and the second end of capacitor C42 is connected to the second end of the thermistor RT10.

[0069] In one embodiment, the battery parameter acquisition module 150 further includes a filter capacitor C12, the first end of which is connected to the positive voltage terminal of the battery parameter acquisition chip, and the second end of which is connected to the ground terminal of the battery parameter acquisition chip.

[0070] Please refer to Figure 4 In one embodiment, the switch module 140 provided in this application includes a first terminal and a second terminal (i.e., Figure 4 The A and B terminals of the switch module 140 constitute the relative contact points of the circuit. To achieve simple and reliable on / off control, one of the first and second terminals of the switch module 140 in this application uses an elastic conductor with a certain elastic deformation capability, while the other terminal uses a metal conductor with higher rigidity. In the initial state, a removable electrical insulator is provided between the elastic conductor and the metal conductor to isolate the electrical connection between the two conductive terminals. This electrical insulator can be made of engineering plastic sheet, and its thickness and hardness are designed to resist the compressive force of the elastic conductor, thereby keeping the switch module 140 in the off state. At this time, because the elastic conductor is deformed under structural compression, it has an outward elastic restoring force.

[0071] When it is necessary to turn on the switch module 140, the removable electrical insulator is pulled out or removed. As the electrical insulator is removed, the originally restricted elastic conductor automatically bounces back towards the metal conductor under the action of its elastic restoring force, and forms a reliable contact with the metal conductor at the second end, thereby electrically connecting the first end and the second end of the switch module 140.

[0072] In one embodiment, to improve the anti-static capability of the battery interface during use and prevent external electrostatic discharge from coupling into the circuit through the device connection terminal 110, causing chip damage or malfunction, an electrostatic protection component is provided at the positive device connection terminal 111. This application uses a bidirectional diode T2 as the electrostatic discharge device, with its first terminal electrically connected to the positive device connection terminal 111 and its second terminal grounded.

[0073] Please refer to Figure 5In another embodiment, a battery protection board 10 is provided, which includes the battery protection circuit 100 in any of the above embodiments. The battery protection board 10 typically consists of a circuit board and various functional circuit units arranged on the board, including the battery charge / discharge protection module 130, the bidirectional series switch D1, the battery parameter acquisition module 150, sampling resistors, filter capacitors, electrostatic discharge protection devices, and device connection terminals, etc., in the battery protection circuit 100. By integrating the battery protection circuit 100 onto the same circuit board, all electrical connections can be implemented in a fixed wiring manner, ensuring the signal transmission quality and electrical reliability between modules. Since the battery protection circuit 100 has been clearly described in the above embodiments, it will not be repeated here.

[0074] The above-described specific examples are for illustrative purposes only and are not intended to limit the scope of this invention. Those skilled in the art to which this invention pertains can make various simple deductions, modifications, or substitutions based on the concept of this invention.

Claims

1. A battery protection circuit, characterized in that, include: The device connection terminal includes a positive device connection terminal and a negative device connection terminal; The cell connection terminal includes a positive cell connection terminal and a negative cell connection terminal; A battery charge / discharge protection module, wherein the first end of the battery charge / discharge protection module is connected to the negative electrode device connection terminal, and the second end of the battery charge / discharge protection module is used to connect to the negative electrode cell connection terminal; A switch module, wherein a first end of the switch module is used to connect the positive electrode connection terminal and the positive electrode cell connection terminal, and a second end of the switch module is connected to the third end of the battery charge / discharge protection module; a removable electrical insulator is provided between the first end and the second end of the switch module, and the removable electrical insulator can be removed when the battery is correctly snapped on, so that the switch module is closed and the battery charge / discharge protection module is turned on.

2. The battery protection circuit as described in claim 1, characterized in that, The battery charge / discharge protection module includes: A current detection module, wherein the first end of the current detection module is connected to the third end of the battery charge and discharge protection module, and the second end of the current detection module is connected to the first end of the battery charge and discharge protection module. A charge / discharge switching module, wherein a first end of the charge / discharge switching module is connected to a first end of the battery charge / discharge protection module, and a second end of the charge / discharge switching module is connected to a second end of the battery charge / discharge protection module; The current detection module is used to close the charge / discharge switching module when the removable electrical insulator is removed, so as to activate the battery charge / discharge protection module.

3. The battery protection circuit as described in claim 2, characterized in that, The current detection module includes a current detection chip and a resistor R4; The current detection chip includes a power input terminal, a power ground terminal, and a charge / discharge detection terminal; The power input terminal of the current detection chip is connected to the first terminal of the current detection module, the power ground terminal of the current detection chip is connected to the second terminal of the battery charge and discharge protection module, the charge and discharge detection terminal of the current detection chip is connected to the first terminal of resistor R4, and the second terminal of resistor R4 is connected to the second terminal of the current detection module.

4. The battery protection circuit as described in claim 3, characterized in that, The charge / discharge switching module includes a bidirectional series switch transistor, resistors R1 and R3, and capacitors C2 and C3; the current detection chip also includes a discharge control terminal and a charge control terminal. The first end of the bidirectional series switch is connected to the first end of the charge / discharge switching module, the second end of the bidirectional series switch is connected to the second end of the charge / discharge switching module, the first control end of the bidirectional series switch is connected to the first end of the resistor R1, the second end of the resistor R1 is connected to the discharge control end, the second control end of the bidirectional series switch is connected to the first end of the resistor R3, and the second end of the resistor R3 is connected to the charging control end; the first end of the bidirectional series switch is also connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the first end of the capacitor C3, and the second end of the capacitor C3 is connected to the second end of the bidirectional series switch.

5. The battery protection circuit as described in claim 1, characterized in that, The battery protection circuit also includes a filter capacitor C1, the first end of which is connected to the positive cell connection terminal, and the second end of which is connected to the negative cell connection terminal.

6. The battery protection circuit as described in claim 1, characterized in that, The battery protection circuit also includes a sampling resistor R11 and a battery parameter acquisition module; The first end of the sampling resistor R11 is connected to the negative electrode cell connection terminal, and the second end of the sampling resistor R11 is connected to the second terminal of the battery charge and discharge protection module. The first sampling terminal of the battery parameter acquisition module is connected to the first terminal of the resistor R11, and the second sampling terminal of the battery parameter acquisition module is connected to the second terminal of the resistor R11; the battery parameter acquisition module is used to acquire the operating current of the battery through the sampling resistor R11.

7. The battery protection circuit as described in claim 6, characterized in that, The battery parameter acquisition module includes a battery parameter acquisition chip, a current-limiting resistor R10, and a filtering module. The battery parameter acquisition chip includes a first voltage input terminal and a ground terminal; The first end of the current-limiting resistor R10 is connected to the positive electrode cell connection terminal, and the second end of the current-limiting resistor R10 is connected to the first voltage input terminal. The first end of the filter module is connected to the second end of the current-limiting resistor R10, and the second end of the filter module is connected to the ground terminal.

8. The battery protection circuit as described in claim 7, characterized in that, The battery parameter acquisition module further includes a thermistor RT10 and a capacitor C42. The battery parameter acquisition chip further includes a second voltage input terminal and a thermistor voltage detection terminal. The first terminal of the thermistor RT10 is connected to the second voltage input terminal, and the second terminal of the thermistor RT10 is connected to the thermistor voltage detection terminal. The first terminal of the capacitor C42 is connected to the first terminal of the thermistor RT10, and the second terminal of the capacitor C42 is connected to the second terminal of the thermistor RT10.

9. The battery protection circuit as described in claim 1, characterized in that, One of the first end and the second end of the switch module is an elastic conductor, and the other is a metallic conductor; when the removable electrical insulator is located between the first end and the second end of the switch module, the elastic conductor has an elastic restoring force; when the removable electrical insulator is removed, the elastic conductor, under the action of the elastic restoring force, connects the first end and the second end of the switch module.

10. A battery protection board, characterized in that, Includes the battery protection circuit as described in any one of claims 1-9.

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