Overelectric stress protection circuit and battery

Abstract

The embodiment of the utility model provides an over-electric stress protection circuit and a battery, which are used for connecting a battery system and comprise a voltage detection module and a switch control module, the voltage detection module comprises a single chip microcomputer and a pulse voltage acquisition unit; a switch control module, a diode clamping unit, a transistor action unit and a first transistor; the single-chip microcomputer is connected between the grid electrode of the first transistor and the pulse voltage acquisition unit. The pulse voltage acquisition unit is connected with the battery system; the transistor action unit is connected in parallel between the source electrode and the drain electrode of the first transistor; the diode clamping unit is connected between the drain electrode of the first transistor and the protection chip; the transistor action unit is connected with the voltameter chip, and the diode clamping unit and the transistor action unit are turned off along with the conduction of the first transistor. Electric stress monitoring of the battery can be realized, and the chip of the battery protection board can be protected under the condition that over-electric stress occurs in the process from delivery to transportation of the battery.

Description

Technical Field

[0001] This application relates to the technical field of battery electrical stress monitoring, and in particular to an over-electrical stress protection circuit and a battery. Background Art

[0002] Lithium-ion batteries are ideal power sources for current electric vehicles due to their excellent characteristics such as high power density and energy density, no memory effect, low self-discharge, long cycle life, and no pollution.

[0003] Lithium-ion batteries will generate chemical reactions, heat generation and heat transfer, and electrical stress, and they affect each other. Among them, the generation of electrical stress has an important impact on the performance of lithium-ion batteries. External loads, diffusion-induced stress, and thermal stress will all cause electrical stress in lithium-ion batteries. When the electrical stress increases to a certain extent, it may cause electrode rupture and diaphragm failure, thereby reducing the performance of lithium-ion batteries, shortening the service life of lithium-ion batteries, and leading to safety problems such as short circuits. Utility Model Content

[0004] In view of this, the purpose of this application is to provide an over-electrical stress protection circuit and a battery, which can realize battery electrical stress monitoring and protect the chip of the battery protection board when over-electrical stress occurs during the process from battery factory to transportation.

[0005] In a first aspect, an embodiment of this application provides an over-electrical stress protection circuit for connecting to a battery system. The over-electrical stress protection circuit includes a voltage detection module and a switch control module;

[0006] The voltage detection module includes a single-chip microcomputer and a pulse voltage acquisition unit;

[0007] The switch control module includes a diode clamping unit for controlling the power supply of the protection chip in the battery system, a transistor action unit for controlling the power supply of the fuel gauge chip in the battery system, and a first transistor;

[0008] The single-chip microcomputer is connected between the gate of the first transistor and the pulse voltage acquisition unit; the pulse voltage acquisition unit is connected to the battery system;

[0009] The transistor action unit is connected in parallel between the source and the drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip;

[0010] The transistor action unit is connected to the fuel gauge chip, and among them, the diode clamping unit and the transistor action unit are turned off when the first transistor is turned on.

[0011] In combination with the first aspect, the embodiment of the present application provides a first possible implementation manner of the first aspect. The transistor operation unit includes a first transistor sub-circuit and a second transistor sub-circuit;

[0012] The first transistor sub-circuit is connected between the second transistor sub-circuit and the ground;

[0013] The second transistor sub-circuit is connected between the fuel gauge chip and the power supply terminal corresponding to the fuel gauge chip;

[0014] The first transistor sub-circuit is connected in parallel between the source and the drain of the first transistor.

[0015] In combination with the first aspect, the embodiment of the present application provides a second possible implementation manner of the first aspect. The first transistor sub-circuit includes a second transistor, a first resistor, and a second resistor;

[0016] The first resistor is connected between the drain of the first transistor and the gate of the second transistor;

[0017] The second resistor is connected between the source of the first transistor and the gate of the second transistor;

[0018] The source of the second transistor is connected to the source of the first transistor and grounded, and the drain of the second transistor is connected to the second transistor sub-circuit.

[0019] In combination with the first aspect, the embodiment of the present application provides a third possible implementation manner of the first aspect. The second transistor sub-circuit includes a third transistor, a third resistor, and a first capacitor;

[0020] The gate of the third transistor is connected to the first transistor sub-circuit, the source is connected to the power supply terminal, and the drain is connected to the fuel gauge chip;

[0021] The third resistor is connected between the gate and the source of the third transistor;

[0022] The first capacitor is connected between the gate and the source of the third transistor.

[0023] In combination with the first aspect, the embodiment of the present application provides a fourth possible implementation manner of the first aspect. A fourth resistor is provided between the drain of the second transistor and the gate of the third transistor.

[0024] In combination with the first aspect, the embodiment of the present application provides a fifth possible implementation manner of the first aspect. The diode clamping unit includes a first diode, a second diode, and a fifth resistor;

[0025] One end of the fifth resistor is connected to the drain of the first transistor, and the other end is respectively connected to the cathode of the first diode and the second diode;

[0026] The anode of the first diode is connected between the protection chip and the corresponding charge enable transistor;

[0027] The anode of the second diode is connected between the protection chip and the corresponding discharge enable transistor.

[0028] Combined with the first aspect, the embodiment of the present application provides a sixth possible implementation manner of the first aspect. The pulse voltage acquisition unit includes a connector voltage acquisition terminal and a battery cell voltage acquisition terminal;

[0029] The connector voltage acquisition terminal is connected between the connector in the battery system and the single-chip microcomputer, and is used to acquire the connector voltage and input it to the single-chip microcomputer;

[0030] The battery cell voltage acquisition terminal is connected between the battery cell voltage output port of the connector in the battery system and the single-chip microcomputer, and is used to acquire the battery cell voltage and input it to the single-chip microcomputer.

[0031] Combined with the first aspect, the embodiment of the present application provides a seventh possible implementation manner of the first aspect. The voltage detection module further includes a single-chip microcomputer mode switching terminal;

[0032] The single-chip microcomputer mode switching terminal is connected between the mode control port of the connector in the battery system and the single-chip microcomputer.

[0033] Combined with the first aspect, the embodiment of the present application provides an eighth possible implementation manner of the first aspect. The voltage detection module further includes a single-chip microcomputer power supply path. The single-chip microcomputer power supply path includes a single-chip microcomputer power supply terminal, an inductor, a second capacitor, a third capacitor, and a transient voltage suppression diode;

[0034] The inductor is connected between the single-chip microcomputer power supply terminal and the single-chip microcomputer;

[0035] One end of the second capacitor is connected to the single-chip microcomputer, and the other end is grounded;

[0036] One end of the third capacitor is connected to the single-chip microcomputer, and the other end is grounded;

[0037] One end of the transient voltage suppression diode is connected to the single-chip microcomputer, and the other end is grounded.

[0038] In the second aspect, the embodiment of the present application provides a battery, including the overstress protection circuit as described in any one of the first aspects of the embodiments of the present application.

[0039] An over - electrical - stress protection circuit and a battery provided by an embodiment of the present application are used to connect to a battery system. The over - electrical - stress protection circuit includes a voltage detection module and a switch control module. The voltage detection module includes a single - chip microcomputer and a pulse voltage acquisition unit. The switch control module includes a diode clamping unit for controlling the power supply of a protection chip in the battery system, a transistor action unit for controlling the power supply of a fuel gauge chip in the battery system, and a first transistor. The single - chip microcomputer is connected between the gate of the first transistor and the pulse voltage acquisition unit. The pulse voltage acquisition unit is connected to the battery system. The transistor action unit is connected in parallel between the source and the drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip. The transistor action unit is connected to the fuel gauge chip. Wherein, the diode clamping unit and the transistor action unit are turned off when the first transistor is turned on. It can realize the monitoring of the battery electrical stress, and protect the chips on the battery protection board when over - electrical stress occurs during the process from the battery leaving the factory to transportation. Brief Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, so they should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0041] Figure 1 It is a schematic structural diagram of an over - electrical - stress protection circuit provided by an embodiment of the present invention;

[0042] Figure 2 It is a schematic structural diagram of a switch control module provided by an embodiment of the present invention;

[0043] Figure 3 It is a schematic structural diagram of another switch control module provided by an embodiment of the present invention;

[0044] Figure 4 It is a schematic structural diagram of a voltage detection module provided by an embodiment of the present invention.

[0045] Icons: 100 - Overvoltage Stress Protection Circuit; 110 - Voltage Detection Module; 120 - Switch Control Module; 111 - Single Chip Microcomputer; 112 - Pulse Voltage Acquisition Unit; 121 - Diode Clamping Unit; 122 - Transistor Action Unit; 123 - First Transistor; 200 - First Transistor Sub - circuit; 300 - Second Transistor Sub - circuit; 201 - Second Transistor; 202 - First Resistor; 203 - Second Resistor; 301 - Third Transistor; 302 - Third Resistor; 303 - First Capacitor; 124 - Fourth Resistor; 1211 - First Diode; 1212 - Second Diode; 1213 - Fifth Resistor; 1121 - Connector Voltage Acquisition Terminal; 1122 - Cell Voltage Acquisition Terminal; 1123 - Single Chip Microcomputer Mode Switching Terminal; 113 - Single Chip Microcomputer Power Supply Path; 1131 - Single Chip Microcomputer Power Supply Terminal; 1132 - Inductor; 1133 - Second Capacitor; 1134 - Third Capacitor; 1135 - Transient Voltage Suppression Diode. Detailed Implementation Modes

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. The components of the embodiments of the present utility model described and illustrated herein can be arranged and designed in various different configurations.

[0047] Therefore, the following detailed description of the embodiments of the present utility model provided in the drawings is not intended to limit the scope of the present utility model claimed, but merely represents selected embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0049] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, or the orientation or positional relationships in which the utility model product is usually placed during use, or the orientation or positional relationships commonly understood by those skilled in the art. These are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

[0050] In addition, terms such as "first", "second", "third", etc. are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0051] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0052] Considering that existing lithium-ion batteries will generate chemical reactions, heat generation, heat transfer, and electrical stress, etc., and they affect each other. Among them, the generation of electrical stress has an important impact on the performance of lithium-ion batteries. External loads, diffusion-induced stress, and thermal stress, etc. will all cause electrical stress in lithium-ion batteries. When the electrical stress increases to a certain extent, it may cause electrode rupture and diaphragm failure, thereby reducing the performance of lithium-ion batteries and shortening the service life of lithium-ion batteries, resulting in safety problems such as short circuits.

[0053] The embodiment of the present application provides an over-electrical stress protection circuit and a battery for connecting to a battery system. The over-electrical stress protection circuit includes a voltage detection module and a switch control module; the voltage detection module includes a single-chip microcomputer and a pulse voltage acquisition unit; the switch control module includes a diode clamping unit for controlling the power supply of the protection chip in the battery system, a transistor action unit for controlling the power supply of the fuel gauge chip in the battery system, and a first transistor; the single-chip microcomputer is connected between the gate of the first transistor and the pulse voltage acquisition unit; the pulse voltage acquisition unit is connected to the battery system; the transistor action unit is connected in parallel between the source and drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip; the transistor action unit is connected to the fuel gauge chip, wherein the diode clamping unit and the transistor action unit are turned off when the first transistor is turned on. It can realize the monitoring of the electrical stress of the battery and protect the chips of the battery protection board when over-electrical stress occurs during the process from the battery leaving the factory to transportation.

[0054] Please refer to Figure 1 , Figure 1 which is one of the schematic structural diagrams of an over-electrical stress protection circuit 100 provided in this embodiment:

[0055] As Figure 1As shown in the figure, an overvoltage stress protection circuit 100 provided in this embodiment includes a voltage detection module 110 and a switch control module 120. Among them, the voltage detection module 110 includes a single-chip microcomputer 111 and a pulse voltage acquisition unit 112; the switch control module 120 includes a diode clamping unit 121 for controlling the power supply of the protection chip in the battery system, a transistor action unit 122 for controlling the power supply of the fuel gauge chip in the battery system, and a first transistor 123.

[0056] Specifically, the single-chip microcomputer 111 is connected between the gate of the first transistor 123 and the pulse voltage acquisition unit 112; the pulse voltage acquisition unit 112 is connected to the battery system; the transistor action unit 122 is connected in parallel between the source and drain of the first transistor 123, and the diode clamping unit 121 is connected between the drain of the first transistor 123 and the protection chip; the transistor action unit 122 is connected to the fuel gauge chip. Among them, the diode clamping unit 121 and the transistor action unit 122 are turned off when the first transistor 123 is turned on.

[0057] Here, the overvoltage stress protection circuit 100 can be used to connect to a battery system. The battery system includes battery cells, a battery protection chip, a fuel gauge, and a connector. The battery cells, the battery protection chip, and the fuel gauge are all connected to the connector. The voltage detection module 110 is used to monitor the pulse voltage generated by the battery cells in real time through the pulse voltage acquisition unit 112, and send the real-time monitoring result of the pulse voltage to the single-chip microcomputer 111.

[0058] In a specific implementation, during battery transportation or storage: the voltage detection module 110 monitors the voltage of the battery cells and the voltage of the battery connector in real time through the pulse voltage acquisition unit 112. If the pulse voltage acquisition unit 112 detects a pulse voltage, the overvoltage stress protection circuit 100 controls the first transistor 123 to disconnect vulnerable chips such as the fuel gauge and the battery protection chip from the connector. When no abnormality is detected, the overvoltage stress protection circuit 100 controls the first transistor 123 to enable chips such as the fuel gauge and the battery protection chip to work normally.

[0059] It should be noted that the transistor action unit 122 is turned off when the drain-source of the first transistor 123 is turned on.

[0060] Here, whenever the voltage detection module 110 detects an abnormal voltage or a pulse voltage, the single-chip microcomputer 111 automatically accumulates the number of times and records the occurrence time, so as to read the recorded data later and confirm the station where the abnormality occurred.

[0061] Furthermore, when the battery transportation reaches the destination, the data of the single-chip microcomputer 111 can be read through the upper computer software of the single-chip microcomputer 111 to confirm the number of abnormal data and the occurrence time, so as to identify which link in the transportation process has an overvoltage stress situation.

[0062] Further, during the process of assembling the battery into a finished product, the single-chip microcomputer 111 can also monitor the voltage of the battery cell and the voltage of the battery connector in real time. If a pulsed voltage is detected, the first transistor 123 is controlled to disconnect the vulnerable chips such as the fuel gauge and the battery protection chip from the connector. When no abnormality is detected, the first transistor 123 is controlled to make the chips such as the fuel gauge and the battery protection chip work in a normal state.

[0063] As a possible implementation manner, whenever an abnormal voltage or a pulsed voltage is detected, the single-chip microcomputer 111 automatically accumulates and records the occurrence time of the number of times. When the assembly of the battery finished product is completed, the finished circuit will read the recorded data of the single-chip microcomputer 111 in the over-electrical-stress protection circuit 100 and check the over-electrical-stress workstations during the assembly process.

[0064] Here, when the battery finished product is sold after-sales, the data of the single-chip microcomputer 111 in the over-electrical-stress protection circuit 100 can be read to confirm the time record of the occurrence of the abnormality, which can be used as reference data to evaluate what over-electrical stresses the battery has suffered, and through simulation verification, determine whether it will cause abnormalities during use.

[0065] An over-electrical-stress protection circuit provided by an embodiment of the present application is used to connect to a battery system. The over-electrical-stress protection circuit includes a voltage detection module and a switch control module; the voltage detection module includes a single-chip microcomputer and a pulsed voltage acquisition unit; the switch control module includes a diode clamping unit for controlling the power supply of the protection chip in the battery system, a transistor action unit for controlling the power supply of the fuel gauge chip in the battery system, and a first transistor; the single-chip microcomputer is connected between the gate of the first transistor and the pulsed voltage acquisition unit; the pulsed voltage acquisition unit is connected to the battery system; the transistor action unit is connected in parallel between the source and the drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip; the transistor action unit is connected to the fuel gauge chip, wherein the diode clamping unit and the transistor action unit are turned off when the first transistor is turned on. It can realize the monitoring of the battery electrical stress and protect the chips on the battery protection board when over-electrical stress occurs during the process from the battery leaving the factory to transportation.

[0066] Please refer to Figure 2 , Figure 2 which is a schematic structural diagram of a switch control module 120 provided by this embodiment.

[0067] As shown in Figure 2As shown in the figure, the switch control module 120 provided in this embodiment includes: a diode clamping unit 121, a transistor action unit 122, and a first transistor 123. The transistor action unit 122 includes: a first transistor sub-circuit 200 and a second transistor sub-circuit 300; the first transistor sub-circuit 200 includes a second transistor 201, a first resistor 202, and a second resistor 203; the second transistor sub-circuit 300 includes a third transistor 301, a third resistor 302, and a first capacitor 303; a fourth resistor 124 is provided between the drain of the second transistor 201 and the gate of the third transistor 301.

[0068] Specifically, the first transistor sub-circuit 200 is connected between the second transistor sub-circuit 300 and the ground; the second transistor sub-circuit 300 is connected between the fuel gauge chip and the power supply terminal corresponding to the fuel gauge chip; the first transistor sub-circuit 200 is connected in parallel between the source and the drain of the first transistor 123. The first resistor 202 is connected between the drain of the first transistor 123 and the gate of the second transistor 201; the second resistor 203 is connected between the source of the first transistor 123 and the gate of the second transistor 201; the source of the second transistor 201 is connected to the source of the first transistor 123 and grounded, and the drain of the second transistor 201 is connected to the second transistor sub-circuit 300. The gate of the third transistor 301 is connected to the first transistor sub-circuit 200, the source is connected to the power supply terminal, and the drain is connected to the fuel gauge chip; the third resistor 302 is connected between the gate and the source of the third transistor 301; the first capacitor 303 is connected between the gate and the source of the third transistor 301.

[0069] In a specific implementation, the gate of the first transistor 123 serves as the input end of the switch control module 120 and is also the output end of the voltage detection module 110. The drain of the third transistor 301 serves as the output end of the switch control module 120 for outputting a control signal for controlling the power supply of the fuel gauge chip in the battery system. The output end of the voltage detection module 110 is in a low level state when the voltage detection module 110 does not detect any abnormal voltage in the cell voltage, the connector voltage, and the signal corresponding to the communication port of the connector.

[0070] Here, when the voltage detection module 110 detects any abnormal voltage in the cell voltage, the connector voltage, and the signal corresponding to the communication port of the connector, the gate of the first transistor 123 becomes high level, thereby causing the drain-source of the first transistor 123 to change from off to on, and then the drain-source of the second transistor 201 follows the drain-source of the first transistor 123 to conduct and changes from on to off.

[0071] Further, as the drain-source of the second transistor 201 changes from conducting to non-conducting, the third transistor 301 changes from conducting to non-conducting. As a result, the power supply to the fuel gauge chip in the battery system becomes non-conducting with the disconnection of the third transistor 301, thereby cutting off the power supply to the fuel gauge chip and protecting the fuel gauge chip in the battery system from the abnormal voltage of the battery cell.

[0072] Please refer to Figure 3 , Figure 3 which is a schematic structural diagram of another transistor action unit 122 provided in this embodiment.

[0073] As Figure 3 shown in

[0074] Specifically, one end of the fifth resistor 1213 is connected to the drain of the first transistor 123, and the other end is respectively connected to the cathodes of the first diode 1211 and the second diode 1212; the anode of the first diode 1211 is connected between the protection chip and the corresponding charge enable transistor; the anode of the second diode 1212 is connected between the protection chip and the corresponding discharge enable transistor.

[0075] Here, in the battery system, a charge enable transistor and a discharge enable transistor are provided between the protection chip and the connector. A charge enable terminal is provided between the charge enable transistor and the protection chip, and the anode of the first diode 1211 is connected to this charge enable terminal. The charge enable terminal is at a high level in the normal state to control the conduction of the charge enable transistor. When the pulse voltage acquisition unit 112 detects a pulse voltage, due to the clamping of the first diode 1211, as the first transistor 123 changes from a high level to a low level, the charge enable transistor then changes from conducting to non-conducting.

[0076] Further, a discharge enabling terminal is provided between the discharge enabling transistor and the protection chip, and the anode of the second diode 1212 is connected to this discharge enabling terminal. The discharge enabling terminal is at a high level in the normal state, controlling the conduction of the discharge enabling transistor. When the pulse voltage acquisition unit 112 detects a pulse voltage, due to the clamping of the second diode 1212, it changes from a high level to a low level along with the first transistor 123, and then the discharge enabling transistor changes from conduction to cutoff.

[0077] Please refer to Figure 4 , Figure 4 which is a schematic structural diagram of a voltage detection module 110 provided in this embodiment.

[0078] As Figure 4 shown in

[0079] the voltage detection module 110 provided in this embodiment includes: a single-chip microcomputer 111 and a pulse voltage acquisition unit 112. The pulse voltage acquisition unit 112 includes a connector voltage acquisition terminal 1121, a cell voltage acquisition terminal 1122, and a single-chip microcomputer mode switching terminal 1123; the voltage detection module 110 further includes a single-chip microcomputer power supply path 113, and the single-chip microcomputer power supply path 113 includes a single-chip microcomputer power supply terminal 1131, an inductor 1132, a second capacitor 1133, a third capacitor 1134, and a transient voltage suppression diode 1135.

[0080] Specifically, the connector voltage acquisition terminal 1121 is connected between the connector in the battery system and the single-chip microcomputer 111, and is used to collect the connector voltage and input it to the single-chip microcomputer 111; the cell voltage acquisition terminal 1122 is connected between the cell voltage output port of the connector in the battery system and the single-chip microcomputer 111, and is used to collect the cell voltage and input it to the single-chip microcomputer 111. The single-chip microcomputer mode switching terminal 1123 is connected between the mode control port of the connector in the battery system and the single-chip microcomputer 111. The inductor 1132 is connected between the single-chip microcomputer power supply terminal 1131 and the single-chip microcomputer 111; one end of the second capacitor 1133 is connected to the single-chip microcomputer 111, and the other end is grounded; one end of the third capacitor 1134 is connected to the single-chip microcomputer 111, and the other end is grounded; one end of the transient voltage suppression diode 1135 is connected to the single-chip microcomputer 111, and the other end is grounded.

[0080] Here, the single-chip microcomputer mode switching terminal 1123 is used to control the working mode switching of the single-chip microcomputer 111 according to the output of the mode control port of the connector in the battery system. When the single-chip microcomputer mode switching terminal 1123 is at a high level, the single-chip microcomputer mode switching terminal 1123 is in a general input / output data transmission mode, and the single-chip microcomputer 111 can detect whether there is an abnormal voltage situation in the battery system.

[0081] Further, when the single-chip microcomputer mode switching terminal 1123 is at a low level, the single-chip microcomputer mode switching terminal 1123 is in the communication mode, and in this mode, the single-chip microcomputer 111 can be read for data.

[0082] As a possible implementation manner, an embodiment of the present application further provides a battery, including an overvoltage stress protection circuit as Figures 1-4 shown in any one of the above.

[0083] An overvoltage stress protection circuit and a battery provided by an embodiment of the present application are used to connect to a battery system. The overvoltage stress protection circuit includes a voltage detection module and a switch control module; the voltage detection module includes a single-chip microcomputer and a pulse voltage acquisition unit; the switch control module includes a diode clamping unit for controlling the power supply of a protection chip in the battery system, a transistor action unit for controlling the power supply of a fuel gauge chip in the battery system, and a first transistor; the single-chip microcomputer is connected between the gate of the first transistor and the pulse voltage acquisition unit; the pulse voltage acquisition unit is connected to the battery system; the transistor action unit is connected in parallel between the source and the drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip; the transistor action unit is connected to the fuel gauge chip, wherein the diode clamping unit and the transistor action unit are turned off when the first transistor is turned on. It can realize the monitoring of the battery electrical stress, and protect the chips on the battery protection board when overvoltage stress occurs during the process from the battery leaving the factory to transportation.

[0084] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An over-stress protection circuit for connecting a battery system, characterized in that: The over-voltage stress protection circuit includes a voltage detection module and a switch control module; The voltage detection module includes a single chip microcomputer and a pulse voltage acquisition unit; The switch control module includes a diode clamping unit for controlling the power supply of the protection chip in the battery system, a transistor action unit for controlling the power supply of the fuel gauge chip in the battery system, and a first transistor; The single chip microcomputer is connected between the gate of the first transistor and the pulse voltage acquisition unit; the pulse voltage acquisition unit is used to connect to the battery system; The transistor action unit is connected in parallel between the source and drain of the first transistor, and the diode clamping unit is connected between the drain of the first transistor and the protection chip; The transistor action unit is connected to the electricity meter chip, wherein the diode clamp unit and the transistor action unit are turned off as the first transistor is turned on.

2. The over-stress protection circuit according to claim 1, characterized in that: The transistor action unit includes a first transistor sub-circuit and a second transistor sub-circuit; The first transistor subcircuit is connected between the second transistor subcircuit and ground; The second transistor sub-circuit is connected between the fuel gauge chip and a power supply terminal corresponding to the fuel gauge chip; The first transistor sub-circuit is connected in parallel between the source and the drain of the first transistor.

3. The over-voltage stress protection circuit according to claim 2, characterized in that: The first transistor subcircuit includes a second transistor, a first resistor and a second resistor; The first resistor is connected between the drain of the first transistor and the gate of the second transistor; The second resistor is connected between the source of the first transistor and the gate of the second transistor; A source of the second transistor is connected to a source of the first transistor and is grounded, and a drain of the second transistor is connected to the second transistor sub-circuit.

4. The over-stress protection circuit according to claim 3, characterized in that: The second transistor sub-circuit includes a third transistor, a third resistor and a first capacitor; The gate of the third transistor is connected to the first transistor sub-circuit, the source is connected to the power supply terminal, and the drain is connected to the fuel gauge chip; The third resistor is connected between the gate and the source of the third transistor; The first capacitor is connected between the gate and the source of the third transistor.

5. The over-voltage stress protection circuit according to claim 4, characterized in that: A fourth resistor is arranged between the drain of the second transistor and the gate of the third transistor.

6. The over-stress protection circuit according to claim 1, characterized in that: The diode clamping unit includes a first diode, a second diode and a fifth resistor; One end of the fifth resistor is connected to the drain of the first transistor, and the other end is connected to the cathodes of the first diode and the second diode respectively; The anode of the first diode is connected between the protection chip and the corresponding charge enable transistor; An anode of the second diode is connected between the protection chip and a corresponding discharge enabling transistor.

7. The over-stress protection circuit according to claim 1, characterized in that: The pulse voltage collection unit includes a connector voltage collection terminal and a cell voltage collection terminal; The connector voltage collection terminal is used to be connected between the connector in the battery system and the single-chip microcomputer, and is used to collect the connector voltage and input it into the single-chip microcomputer; The cell voltage collection terminal is used to be connected between the connector in the battery system and the single-chip microcomputer, and is used to collect the cell voltage and input it into the single-chip microcomputer.

8. The over-voltage stress protection circuit according to claim 1, characterized in that: The voltage detection module also includes a single chip computer mode switching terminal; The single-chip microcomputer mode switching terminal is used to connect between a connector in the battery system and the single-chip microcomputer.

9. The over-stress protection circuit according to claim 1, characterized in that: The voltage detection module further includes a single-chip microcomputer power supply path, and the single-chip microcomputer power supply path includes a single-chip microcomputer power supply terminal, an inductor, a second capacitor, a third capacitor, and a transient voltage suppression diode; The inductor is connected between the single chip microcomputer power supply terminal and the single chip microcomputer; One end of the second capacitor is connected to the single chip microcomputer, and the other end is grounded; One end of the third capacitor is connected to the single chip microcomputer, and the other end is grounded; One end of the transient voltage suppression diode is connected to the single chip microcomputer, and the other end is grounded.

10. A battery, characterized in that: The invention comprises an over-stress protection circuit as claimed in any one of claims 1 to 9.

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