Fuse fusing protection circuit and battery module

Abstract

The embodiment of the utility model relates to the technical field of battery protection, in particular to a fuse fusing protection circuit and a battery module. According to the embodiment of the utility model, the first trigger circuit is used for receiving signals of various abnormal conditions, such as battery pack undervoltage, charging and discharging MOS overtemperature protection, primary and secondary loop charging and discharging MOS short circuit, and the like, which are detected by software, and the fuse is fused by controlling the on-off of the power supply conduction circuit. Besides, the voltage of each battery cell of the battery module is subjected to anomaly detection through a second trigger circuit and a third trigger circuit, and when any battery cell is abnormal, the switch can be switched on to fuse the fuse, so that the battery module and related equipment of the battery are protected. And the use safety of the battery module is improved.

Description

Technical Field

[0001] The embodiments of the present utility model relate to the technical field of battery protection, and particularly to a fuse melting protection circuit and a battery module. Background Art

[0002] In the field of lithium batteries, in order to meet the requirements of safety regulations for single-failure faults of PCBA protection devices, abnormal charge and discharge current detection, or dual safety protection of cell voltage, temperature, current, etc., it is necessary to design a fuse circuit controlled by software to drive the NMOS transistor between the three-terminal fuse and the product GND terminal to conduct, so as to achieve the effect of melting the three-terminal fuse.

[0003] Currently, the commonly used circuit for melting the three-terminal fuse relies on a hardware overcharge secondary protection IC to monitor the voltage and trigger melting. The application of this circuit is limited. Only when the overcharge voltage point of a single cell is triggered, the CO terminal of the overcharge secondary protection IC outputs a high level to make the NMOS transistor conduct and trigger the fuse to melt. In many abnormal situations such as battery pack under-voltage detected by software, over-temperature protection of charge and discharge MOS, short circuit of primary and secondary circuit charge and discharge MOS, etc., the three-terminal fuse cannot be actively melted, resulting in easy damage to the battery in other abnormal situations and even potential safety hazards. Summary of the Utility Model

[0004] In view of the above problems, the embodiments of the present utility model provide a fuse melting protection circuit and a battery module, which solve the problem that in many abnormal situations such as battery pack under-voltage detected by software, over-temperature protection of charge and discharge MOS, short circuit of primary and secondary circuit charge and discharge MOS, etc., the three-terminal fuse cannot be actively melted, resulting in easy damage to the battery in other abnormal situations and even potential safety hazards.

[0005] In the first aspect,

[0006] The present utility model provides a fuse melting protection circuit, which is applied to a battery module. The circuit includes:

[0007] A fuse circuit, including a fuse and a switch. The fuse is connected in the loop between the battery positive electrode and the battery output terminal of the battery module, and the switch is connected to the fuse in an enabling manner;

[0008] A power supply conduction circuit, including a power input terminal, a power output terminal, and a trigger control terminal. The power output terminal takes power by connecting to the battery positive electrode or the middle section of the battery, and the power output terminal is connected to the switch in an enabling manner;

[0009] And a first trigger circuit, connected to the trigger control terminal, and melting the three-terminal fuse by controlling the power supply conduction circuit to supply power to the fuse circuit.

[0010] In some alternative embodiments, the fuse is provided with a first connection end, a second connection end, and a first enable end. The first connection end is connected to the positive electrode of the battery, and the second connection end is connected to the output end of the battery. The switch is a first MOS transistor. The gate of the first MOS transistor is connected to the power output end, the drain is connected to the first enable end, and the source is grounded.

[0011] In some alternative embodiments, the power supply conduction circuit includes a first resistor, a second resistor, a first triode, a third resistor, and a fourth resistor.

[0012] The base of the first triode is respectively connected to the second resistor and the first trigger circuit, the emitter is respectively connected to the second resistor and the first resistor, and the collector is connected to the gate of the first MOS transistor and the fourth resistor through the third resistor. The other end of the first resistor is connected to the positive electrode of the battery, and the other end of the fourth resistor is grounded.

[0013] In some alternative embodiments, a second trigger circuit is further included. The second trigger circuit includes a first detection chip, a second MOS transistor, and a fifth resistor. The first detection chip is provided with a first power supply end and a first control end. The first power supply end is connected to the positive electrode of the battery, and the first control end is connected to the gate of the second MOS transistor. The source of the second MOS transistor is connected to the middle section of the battery, and the drain is connected to the base of the first triode through the fifth resistor.

[0014] In some alternative embodiments, the power supply conduction circuit includes a second resistor, a first triode, a third resistor, a fifth resistor, a fourth resistor, and a first detection chip.

[0015] The first detection chip is provided with a first power supply end and a first control end. The first power supply end is connected to the middle section of the battery and the fifth resistor. The first control end is respectively connected to the emitter of the first triode and the second resistor. The other ends of the second resistor and the fifth resistor are connected to the base of the first triode. The other end of the collector of the first triode is connected to the gate of the first MOS transistor and the fourth resistor through the third resistor. The other end of the fourth resistor is grounded.

[0016] In some alternative embodiments, the first trigger circuit includes a second triode and a sixth resistor. The base of the second triode is connected to the signal output end of the main control chip, the collector is connected to the base of the first triode through the sixth resistor, and the emitter is grounded.

[0017] In some alternative embodiments, a third trigger circuit is further included. The third trigger circuit includes a second detection chip and a first voltage-dividing protection circuit. The second detection chip is provided with a second power terminal and a second control terminal. The second power terminal is connected to the middle section of the battery, and the second control terminal is connected to the switcher enabling terminal through the first voltage-dividing protection circuit.

[0018] In some alternative embodiments, the first voltage-dividing protection circuit includes a seventh resistor and a first diode. One end of the seventh resistor is connected to the second control terminal, and the other end of the seventh resistor is connected to the gate of the first MOS transistor through the first diode.

[0019] In some alternative embodiments, the first detection chip and the second detection chip are both provided with at least one first detection terminal for detecting the power of each battery cell in the battery module.

[0020] Second aspect

[0021] The present utility model provides a battery module including the above-mentioned fuse melting protection circuit.

[0022] The present utility model provides a fuse melting protection circuit and a battery module, and the beneficial effects are as follows: In the embodiments of the present utility model, the first trigger circuit receives signals of various abnormal conditions such as under-voltage of the battery pack detected by software, over-temperature protection of the charge and discharge MOS, and short circuit of the main and secondary circuit charge and discharge MOS, and controls the on-off of the power supply conduction circuit, so that the fuse is melted. In addition, the present application also performs abnormal detection on the voltage of each battery cell in the battery module through the second trigger circuit and the third trigger circuit. When any battery cell has an abnormality, the switcher can be turned on to melt the fuse, thereby protecting the battery module and battery-related devices. The safety of using the battery module is improved.

[0023] The above description is only an overview of the technical solutions of the embodiments of the present utility model. In order to be able to understand the technical means of the embodiments of the present utility model more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the embodiments of the present utility model more obvious and understandable, the following specifically describes the embodiments of the present utility model. Description of the drawings

[0024] The drawings are only used to illustrate the embodiments and are not considered as a limitation to the present utility model. And throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0025] Figure 1 Fig. 1 shows a schematic structural diagram of Embodiment 1 of the fuse melting protection circuit provided by the present utility model;

[0026] Figure 2Shows the circuit schematic diagram of Embodiment 2 of the fuse melting protection circuit provided by the present utility model;

[0027] Figure 3 Shows the circuit schematic diagram of Embodiment 3 of the fuse melting protection circuit provided by the present utility model.

[0028] Among them,

[0029] 110. Fuse circuit; 120. Power supply conduction circuit; 130. First trigger circuit; 140. Second trigger circuit; 150. Third trigger circuit; B+. Battery positive electrode; P+. Battery output terminal; U1. First detection chip; U2. Second detection chip; R1. First resistor; R2. Second resistor; R3. Third resistor; R4. Fourth resistor; R5. Fifth resistor; R6. Sixth resistor; R7. Seventh resistor; F1. Fuse; D1. First diode; Q1. First MOS transistor; Q2. Second MOS transistor; Q3. First triode; Q4. Second triode. Detailed implementation manners

[0030] The exemplary embodiments of the present utility model will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model can be implemented in various forms and should not be limited by the embodiments set forth herein.

[0031] Embodiment 1:

[0032] Figure 1 Shows a fuse F1 melting protection circuit provided by the present utility model, which is applied to a battery module. The circuit includes a fuse circuit 110, a power supply conduction circuit 120, and a first trigger circuit. Among them, the fuse circuit 110 specifically includes a fuse F1 and a switch. The fuse F1 is connected in the loop between the battery positive electrode B+ and the battery output terminal P+ of the battery module, and the switch is enabled to connect with the fuse F1. The power supply conduction circuit 120 specifically includes a power input terminal, a power output terminal, and a trigger control terminal. The power output terminal takes power by connecting to the battery positive electrode B+ or the middle section of the battery. The power output terminal is enabled to connect with the switch. The first trigger circuit is connected to the trigger control terminal, and controls the power supply conduction circuit 120 to make the three-terminal fuse F1 melt for the fuse F1 circuit.

[0033] In this embodiment, the power supply conduction circuit 120 can draw power from the positive electrode B+ of the battery in the battery module, or the power supply circuit can also draw power from the middle section of the battery module. Herein, the middle section of the battery module is a connection node located in the middle of the battery module or the positive electrode of the battery cell located in the middle of the battery module. The power supply conduction circuit 120 is used to conduct the input power supply through a switch and voltage division to the switcher, causing the fuse F1 to blow. The fuse F1 can be a three-terminal fuse F1, and the first connection terminal F1_3 and the second connection terminal F1_1 are respectively connected to the battery positive electrode B+ and the battery output terminal P+, forming a path between the battery positive electrode B+ and the battery output terminal P+. The switcher is used to control whether the fuse F1 blows.

[0034] In the embodiment of the present utility model, the first trigger circuit 130 receives signals of many abnormal situations such as battery pack undervoltage, over-temperature protection of charge and discharge MOS, short circuit of main and secondary loop charge and discharge MOS detected by software. By controlling the on-off of the power supply conduction circuit 120, the fuse F1 is caused to blow. In addition, this application also performs abnormal detection on the voltage of each battery cell of the battery module through the second trigger circuit 140 and the third trigger circuit 150. When any battery cell has an abnormality, the switcher can be turned on to blow the fuse F1, thereby realizing the protection of the battery module and battery-related equipment. The safety of using the battery module is improved.

[0035] In some alternative embodiments, the fuse F1 is provided with a first connection terminal F1_3, a second connection terminal F1_1, and a first enable terminal F1_2. The first connection terminal is connected to the battery positive electrode B+, and the second connection terminal is connected to the battery output terminal P+; the switcher is a first MOS transistor Q1. The gate of the first MOS transistor Q1 is connected to the power output terminal, the drain is connected to the first enable terminal, and the source is grounded. In this embodiment, when the first MOS transistor Q1 is turned on, the level of the first enable terminal of the fuse F1 is pulled low, causing the fuse F1 to blow. If the gate electrical signal of the first MOS transistor Q1 is not sufficient to turn it on, the first enable terminal of the fuse F1 is in a floating state, enabling the battery module to work normally.

[0036] In some alternative embodiments, the first trigger circuit 130 includes a second triode Q4 and a sixth resistor R6; the base of the second triode Q4 is connected to the signal output terminal MCU_I / O of the main control chip, the collector is connected to the base of the first triode Q3 through the sixth resistor R6, and the emitter is grounded. In this embodiment, the first trigger circuit 130 is connected to the main control chip of the battery module. The main control chip can be the battery management chip of the battery module. The main control chip can output a level signal through the control signal output terminal by identifying many abnormal situations such as battery pack undervoltage, over-temperature protection of charge and discharge MOS, short circuit of main and secondary loop charge and discharge MOS, so as to turn on the power supply conduction circuit 120.

[0037] Embodiment 2:

[0038] In some alternative embodiments, based on Embodiment 1, the power supply conduction circuit 120 includes a first resistor R1, a second resistor R2, a first triode Q3, a third resistor R3, and a fourth resistor R4. The base of the first triode Q3 is respectively connected to the second resistor R2 and the first trigger circuit, the emitter is respectively connected to the second resistor R2 and the first resistor R1, and the collector is connected to the gate of the first MOS transistor Q1 and the fourth resistor R4 through the third resistor R3; the other end of the first resistor R1 is connected to the battery positive electrode B+, and the other end of the fourth resistor R4 is grounded. It further includes a second trigger circuit 140, and the second trigger circuit 140 includes a first detection chip U1, a second MOS transistor Q2, and a fifth resistor R5. The first detection chip U1 is provided with a first power supply terminal U1_VDD and a first control terminal U1_CO. The first power supply terminal is connected to the battery positive electrode B+, and the first control terminal is connected to the gate of the second MOS transistor Q2; the source of the second MOS transistor Q2 is connected to the middle section of the battery, and the drain is connected to the base of the first triode Q3 through the fifth resistor R5.

[0039] In this embodiment, when the main control chip detects a system fault and needs to start the fuse Fuse, the MCU_I / O outputs a high level to turn on the second triode Q4. Through the voltage division of the battery positive electrode B+B+ by the first resistor R1, the second resistor R2, and the sixth resistor R6, the first triode Q3 is turned on. Then, through the voltage division of the battery positive electrode B+B+ by the first resistor R1, the third resistor R3, and the fourth resistor R4, the first MOS transistor Q1 is turned on to trigger the melting of the fuse F1. The utility model is not limited by the overcharge voltage of the hardware IC and can actively start the fuse Fuse according to various fault trigger conditions set by software. This solution provides a solution for the MCU with a low voltage supply such as 3.3V to actively melt the fuse F1. When the power supply of the main control chip is 3.3V and the first MOS transistor Q1 is a conventional driving MOS, the direct drive level of the I / O port of the main control chip is not sufficient to fully turn on the first MOS transistor Q1. A triode is used for level conversion, and through the voltage division of the B+ level by the resistor, the first MOS transistor Q1 is normally turned on to melt the three-terminal fuse.

[0040] Embodiment 3:

[0041] In some alternative embodiments, based on Embodiment 1, the power supply conduction circuit 120 includes a second resistor R2, a first triode Q3, a third resistor R3, a fifth resistor R5, a fourth resistor R4, and a first detection chip U1; the first detection chip U1 is provided with a first power supply terminal U1_VSS and a first control terminal U1_CO, the first power supply terminal is connected to the middle section of the battery and the fifth resistor R5, and the first control terminal is respectively connected to the emitter of the first triode Q3 and the second resistor R2; the other ends of the second resistor R2 and the fifth resistor R5 are connected to the base of the first triode Q3, and the other end of the collector of the first triode Q3 is connected to the gate of the first MOS transistor Q1 and the fourth resistor R4 through the third resistor R3; the other end of the fourth resistor R4 is grounded. In this embodiment, the first detection chip U1 can be the second trigger circuit 140, which can detect the voltages of the individual battery cells of the battery module, so as to detect and identify the overvoltage chips. The first power supply terminal of the first detection chip U1 can obtain voltage from the middle section of the battery, and then output it to the emitter of the first triode Q3 through the first control terminal, and supply power to the first MOS transistor Q1 through the conduction of the first triode Q3.

[0042] In this embodiment, the present utility model uses a second triode Q4, and through the control circuit of the high-end IC cascaded by sharing the first detection chip U1 and the second detection chip U2, drives the first MOS transistor Q1 to conduct and fuse the fuse F1. Circuit operation logic: Since the first detection chip U1 does not trigger the secondary overcharge protection, the level of the first control terminal is equal to the level of the first power supply terminal of the first detection chip U1, that is, equal to the voltage of the middle-section battery cell. When the main control chip detects a system fault and needs to start fusing the fuse F1, the MCU_I / O outputs a high level to make the second triode Q4 conduct, and through the voltage division of the second resistor R2 and the sixth resistor R6 on the first control terminal, that is, the voltage of the B5 section, makes the first triode Q3 conduct, and then through the voltage division of the third resistor R3 and the fourth resistor R4 on the first control terminal, that is, the voltage of the B5 section, conducts the first MOS transistor Q1 to trigger the fusing of the three-terminal fuse F1.

[0043] This solution is not limited by the overcharge voltage of the hardware IC, and can actively start fusing the Fuse according to various fault trigger conditions set by the software. The present utility model provides a solution for the main control chip powered by a low voltage such as 3.3V to actively fuse the three-terminal fuse F1. When the power supply of the main control chip is 3.3V and the first MOS transistor Q1 is a conventional driving MOS, the direct drive level of the I / O port of the main control chip is not sufficient to make the first MOS transistor Q1 fully conduct. A triode is used for level conversion, and through the voltage division of the resistor on the middle section of the battery pack, the first MOS transistor Q1 is made to conduct normally to fuse the three-terminal fuse F1.

[0044] Embodiment 4:

[0045] In some alternative embodiments, based on Embodiment 1, 2 or 3, this embodiment further includes a third trigger circuit 150. The third trigger circuit 150 includes a second detection chip U2 and a first voltage-dividing protection circuit. The second detection chip U2 is provided with a second power supply terminal U2_VDD and a second control terminal U2_CO. The second power supply terminal is connected to the middle section of the battery, and the second control terminal is connected to the switcher enabling terminal through the first voltage-dividing protection circuit. The first voltage-dividing protection circuit includes a seventh resistor R7 and a first diode D1. One end of the seventh resistor R7 is connected to the second control terminal, and the other end of the seventh resistor R7 is connected to the gate of the first MOS transistor Q1 through the first diode D1. In this embodiment, the third trigger circuit 150 can be used to detect the voltage of the remaining battery cells that cannot be detected by the first detection chip U1. When any battery cell has overvoltage, a level signal can be directly output to the first MOS transistor Q1 through the third trigger circuit 150, and by turning on the first MOS transistor Q1, the fuse F1 is melted. The first voltage-dividing protection circuit uses the seventh resistor R7 for voltage division and the first diode D1 to prevent reverse flow to protect the circuit.

[0046] In some alternative embodiments, both the first detection chip U1 and the second detection chip U2 are provided with at least one first detection terminal to detect the power of each battery cell in the battery module. In this embodiment, the first detection chip U1 and the second detection chip U2 can be provided with multiple first detection terminals for signal detection of each battery cell. Among them, the first detection chip U1 and the second detection chip U2 can be: the CW1051 model chip of the Cellwise brand, or the BQ7718 model chip of the TI brand.

[0047] Embodiment 5:

[0048] The present invention provides a battery module, including the fuse F1 fusing protection circuit described above. In the embodiment of the present invention, the first trigger circuit 130 receives signals of various abnormal conditions such as the battery pack undervoltage, the charging and discharging MOS over-temperature protection, and the primary and secondary circuit charging and discharging MOS short circuits detected by the software, and controls the on / off of the power supply conduction circuit 120, so that the fuse F1 is melted. In addition, this application also performs abnormal detection on the voltage of each battery cell in the battery module through the second trigger circuit 140 and the third trigger circuit 150. When any battery cell has an abnormality, the switcher can be turned on to melt the fuse F1, thereby realizing the protection of the battery module and battery-related devices. The use safety of the battery module is improved.

[0049] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system, or other device. In addition, the embodiments of the present invention are not directed to any particular programming language.

[0050] In the description provided herein, numerous specific details are set forth. However, it will be understood that embodiments of the present invention may be practiced without these specific details. Similarly, in order to streamline the present invention and assist in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. Among them, the claims following the specific implementation manner are hereby expressly incorporated into the specific implementation manner, where each claim itself serves as a separate embodiment of the present invention.

[0051] Those skilled in the art can understand that the modules in the devices in the embodiments can be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments can be combined into a module or unit or component, and in addition, they can be divided into multiple sub-modules or sub-units or sub-components. Except that at least some of such features and / or processes or units are mutually exclusive.

[0052] It should be noted that the above embodiments illustrate the present invention rather than limit the present invention, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim listing several devices, several of these devices may be embodied by the same item of hardware. The use of the words first, second, and third, etc. does not denote any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A fuse protection circuit, characterized in that: Applied in a battery module, the circuit includes: A fuse circuit, comprising a fuse and a switch, wherein the fuse is connected in a loop between a positive electrode of a battery of the battery module and a battery output terminal, and the switch is enabled to be connected to the fuse; A power supply conduction circuit, comprising a power input terminal, a power output terminal, and a trigger control terminal, wherein the power output terminal is connected to the positive electrode of a battery or a middle section of a battery to obtain power, and the power output terminal is connected to the switch enable terminal; And a first trigger circuit is connected to the trigger control terminal, and controls the power supply conduction circuit to supply the fuse circuit so that the three-terminal fuse is blown.

2. A fuse protection circuit according to claim 1, characterized in that: The fuse is provided with a first connection end, a second connection end, and a first enabling end, wherein the first connection end is connected to the positive electrode of the battery, and the second connection end is connected to the output end of the battery; The switch is a first MOS tube, a gate of the first MOS tube is connected to the power output terminal, a drain is connected to the first enable terminal, and a source is grounded.

3. A fuse protection circuit according to claim 2, characterized in that: The power supply conduction circuit includes a first resistor, a second resistor, a first transistor, a third resistor, and a fourth resistor. The base of the first transistor is connected to the second resistor and the first trigger circuit respectively, the emitter is connected to the second resistor and the first resistor respectively, and the collector is connected to the gate of the first MOS tube and the fourth resistor through the third resistor; the other end of the first resistor is connected to the positive electrode of the battery, and the other end of the fourth resistor is grounded.

4. A fuse protection circuit according to claim 3, characterized in that: It also includes a second trigger circuit, which includes a first detection chip, a second MOS tube, and a fifth resistor. The first detection chip is provided with a first power supply end and a first control end. The first power supply end is connected to the positive electrode of the battery, and the first control end is connected to the gate of the second MOS tube; the source of the second MOS tube is connected to the middle node of the battery, and the drain is connected to the base of the first transistor through the fifth resistor.

5. A fuse protection circuit according to claim 2, characterized in that: The power supply conduction circuit includes a second resistor, a first transistor, a third resistor, a fifth resistor, a fourth resistor, and a first detection chip; The first detection chip is provided with a first power supply end and a first control end. The first power supply end is connected to the middle section of the battery and the fifth resistor. The first control end is respectively connected to the emitter of the first transistor and the second resistor. The other ends of the second resistor and the fifth resistor are connected to the base of the first transistor. The other end of the collector of the first transistor is connected to the gate of the first MOS tube and the fourth resistor through the third resistor. The other end of the fourth resistor is grounded.

6. The fuse protection circuit according to claim 4 or 5, characterized in that: The first trigger circuit includes a second transistor and a sixth resistor; the base of the second transistor is connected to the signal output end of the main control chip, the collector is connected to the base of the first transistor through the sixth resistor, and the emitter is grounded.

7. The fuse protection circuit according to claim 6, characterized in that: It also includes a third trigger circuit, which includes a second detection chip and a first voltage-dividing protection circuit. The second detection chip is provided with a second power supply terminal and a second control terminal. The second power supply terminal is connected to the middle section of the battery, and the second control terminal is connected to the switch enable through the first voltage-dividing protection circuit.

8. The fuse protection circuit according to claim 7, characterized in that: The first voltage-dividing protection circuit includes a seventh resistor and a first diode. One end of the seventh resistor is connected to the second control end, and the other end of the seventh resistor is connected to the gate of the first MOS tube through the first diode.

9. The fuse protection circuit according to claim 7, characterized in that: The first detection chip and the second detection chip are both provided with at least one first detection terminal for detecting the power of each battery cell of the battery module.

10. A battery module, characterized in that: The invention comprises a fuse protection circuit as described in any one of claims 1 to 9.

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