Short circuit prevention control circuit of battery module and battery module

Abstract

The utility model discloses a short circuit prevention control circuit of a battery module and the battery module, any two adjacent battery units in the battery module are connected through the short circuit prevention control circuit, and the short circuit prevention control circuit comprises an acquisition unit for acquiring voltage signal pairs at two ends; a subtraction unit which is connected with the acquisition unit and is used for carrying out subtraction operation on the voltage signal pair so as to obtain an output voltage; the first input end of the comparison unit is connected with the output end of the subtraction unit, the second input end of the comparison unit is connected to a preset voltage, and the comparison unit is used for comparing the output voltage with the preset voltage to obtain an output comparison voltage; the input end of the switch control unit is connected with the output end of the comparison unit, and the switch control unit is used for controlling the conduction relation between any two adjacent battery units according to the comparison voltage; therefore, when abnormal large-current discharge of the battery is detected, a protection measure is started immediately, the circuit is high in response speed, and the size of the abnormal current can be adjusted and set.

Description

Technical Field

[0001] The utility model relates to the technical field of battery power supply, in particular to an anti-short circuit control circuit of a battery module and a battery module with the anti-short circuit control circuit. Background Art

[0002] In the related art, a battery module is composed of multiple battery cells connected in series or in parallel to provide the required voltage and current for the device. Figure 1 As shown in the figure, if the negative electrode of B2 is short-circuited with the negative electrode of B1, due to the existence of circuit 1 in the figure, the positive and negative electrodes of battery B1 will be short-circuited directly; similarly, if the negative electrode of B3 is short-circuited with the negative electrode of B1, the positive and negative electrodes of battery B1 and B2 will be short-circuited through circuits 1 and 2 in the circuit; if the negative electrode of B4 is short-circuited with the negative electrode of B1, the positive and negative electrodes of battery B1, B2, and B3 will be short-circuited through circuits 1, 2, and 3 in the circuit; if the negative electrode of B3 is short-circuited with the negative electrode of B2, the positive and negative electrodes of battery B2 will be short-circuited through circuit 2 in the circuit. Negative pole short circuit; if the negative pole of B4 is short-circuited with the negative pole of B3, the positive and negative poles of battery B3 will be short-circuited through the 3 loops in the circuit. Although the battery protection board is currently used to monitor the voltage of each battery and control the current output of the entire battery module, if a short circuit occurs inside the battery module, the battery protection board cannot control it; for example, the short-circuit current of a single 18650 lithium battery can be as high as 60 to 80A. The current is very large during a short circuit. Once a short circuit occurs in the battery inside the module, it will be very dangerous if the equipment cannot be controlled. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems in the above-mentioned technology to a certain extent. To this end, one purpose of the utility model is to propose an anti-short circuit control circuit for a battery module, by adding an anti-short circuit control circuit between any two adjacent battery cells, when an abnormally large current discharge of the battery is detected, the protection measures are immediately activated to limit the battery discharge, and the anti-short circuit control circuit not only has a fast response speed, but also can adjust the abnormal current size.

[0004] To achieve the above-mentioned purpose, the utility model proposes, on the one hand, an anti-short-circuit control circuit of a battery module, wherein any two adjacent battery cells in the battery module are connected through the anti-short-circuit control circuit, wherein the anti-short-circuit control circuit comprises: a collection unit, wherein the collection unit is used to collect voltage signal pairs at both ends; a subtraction unit, wherein a first input end of the subtraction unit is connected to one end of the collection unit, and a second input end of the subtraction unit is connected to the other end of the collection unit, and the subtraction unit performs a subtraction operation on the voltage signal pair to obtain an output voltage; a comparison unit, wherein a first input end of the comparison unit is connected to an output end of the subtraction unit, and a second input end of the comparison unit is connected to a preset voltage, and the comparison unit compares the output voltage with the preset voltage to obtain an output comparison voltage; and a switch control unit, wherein an input end of the switch control unit is connected to an output end of the comparison unit, and the switch control unit controls the conduction relationship between any two adjacent battery cells according to the comparison voltage.

[0005] According to the short-circuit prevention control circuit of the battery module proposed by the utility model, any two adjacent battery cells in the battery module are connected through the short-circuit prevention control circuit, wherein the short-circuit prevention control circuit comprises: a collection unit, the collection unit is used to collect the voltage signal pair at both ends; a subtraction unit, the first input end of the subtraction unit is connected to one end of the collection unit, the second input end of the subtraction unit is connected to the other end of the collection unit, the subtraction unit performs a subtraction operation on the voltage signal pair to obtain an output voltage; a comparison unit, the first input end of the comparison unit is connected to the output end of the subtraction unit, the second input end of the comparison unit is connected to a preset voltage, the comparison unit compares the output voltage with the preset voltage to obtain an output comparison voltage; a switch control unit, the input end of the switch control unit is connected to the output end of the comparison unit, the switch control unit controls the conduction relationship between any two adjacent battery cells according to the comparison voltage; thereby, when it is detected that the battery has an abnormally large current discharge, the protection measures are immediately started to limit the battery discharge, and the short-circuit prevention control circuit not only has a fast response speed, but also can adjust and set the abnormal current size.

[0006] In addition, the short-circuit protection control circuit of the battery module proposed in the utility model may also have the following additional technical features:

[0007] Optionally, the battery module includes a first battery cell, a second battery cell, a third battery cell, a fourth battery cell, a first anti-short circuit control circuit, a second anti-short circuit control circuit and a third anti-short circuit control circuit, the positive electrode of the first battery cell is connected to the input end of the first anti-short circuit control circuit, the output end of the first anti-short circuit control circuit is connected to the negative electrode of the second battery cell, the positive electrode of the second battery cell is connected to the input end of the second anti-short circuit control circuit, the output end of the second anti-short circuit control circuit is connected to the negative electrode of the third battery cell, the positive electrode of the third battery cell is connected to the input end of the third anti-short circuit control circuit, and the output end of the third anti-short circuit control circuit is connected to the negative electrode of the fourth battery cell.

[0008] Optionally, the acquisition unit includes a first resistor, and the first resistor is a sampling resistor.

[0009] Optionally, the subtraction unit includes: a second resistor, one end of the second resistor is connected to one end of the first resistor, and one end of the first resistor serves as the output end of the short-circuit prevention control circuit; a third resistor, one end of the third resistor is connected to the other end of the second resistor, and the other end of the third resistor is grounded; a fourth resistor, one end of the fourth resistor is connected to the other end of the first resistor; a fifth resistor, one end of the fifth resistor is connected to the other end of the fourth resistor; a subtractor, a first input end of the subtractor is connected between the second resistor and the third resistor, a second input end of the subtractor is connected between the fourth resistor and the fifth resistor, and an output end of the subtractor is connected to the other end of the fifth resistor.

[0010] Optionally, the comparison unit includes: a comparator, a non-inverting input terminal of the comparator is connected to the output terminal of the subtractor, and an inverting input terminal of the comparator is connected to a preset voltage through a sixth resistor and a seventh resistor.

[0011] Optionally, the switch control unit includes: a transistor, the base of the transistor is connected to the output end of the comparator, the collector of the transistor serves as the input end of the anti-short circuit control circuit, and has a first node; an eighth resistor, one end of the eighth resistor is connected to the first node, the other end of the eighth resistor is connected to the emitter of the transistor, and has a second node; a ninth resistor, one end of the ninth resistor is connected to the second node, and the other end of the ninth resistor is grounded; a MOS tube, the source of the MOS tube is connected to the first node, the gate of the MOS tube is connected to the second node, and is connected to the ground through a second capacitor, and the drain of the MOS tube is connected to the other end of the first resistor.

[0012] In order to achieve the above object, the utility model further proposes a battery module on the other hand, which includes the above-mentioned short-circuit protection control circuit of the battery module.

[0013] According to the battery module proposed by the utility model, by adding an anti-short circuit control circuit between any two adjacent battery cells, when an abnormally large current discharge of the battery is detected, protection measures are immediately activated to limit the battery discharge. The anti-short circuit control circuit not only has a fast response speed, but also can adjust and set the abnormal current size. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the connection of multiple battery cells of an existing battery module;

[0015] Figure 2 A schematic diagram of connecting multiple battery cells of a battery module according to an embodiment of the utility model;

[0016] Figure 3 The figure is a circuit schematic diagram of a short-circuit protection control circuit of a battery module according to an embodiment of the utility model. DETAILED DESCRIPTION

[0017] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0018] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0019] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] refer to Figure 2-3 As shown, any two adjacent battery cells in the battery module are connected via an anti-short circuit control circuit, wherein the anti-short circuit control circuit includes a collection unit 10, a subtraction unit 20, a comparison unit 30 and a switch control unit 40.

[0021] Among them, the acquisition unit 10 is used to collect the voltage signal pair at both ends; the first input end of the subtraction unit 20 is connected to one end of the acquisition unit 10, and the second input end of the subtraction unit 20 is connected to the other end of the acquisition unit 10, and the subtraction unit 20 performs a subtraction operation on the voltage signal pair to obtain an output voltage; the first input end of the comparison unit 30 is connected to the output end of the subtraction unit 20, and the second input end of the comparison unit 30 is connected to a preset voltage, and the comparison unit 30 compares the output voltage with the preset voltage to obtain an output comparison voltage; the input end of the switch control unit 40 is connected to the output end of the comparison unit 30, and the switch control unit 40 controls the conduction relationship between any two adjacent battery cells according to the comparison voltage.

[0022] As an example, Figure 2 As shown, the battery module includes a first battery cell, a second battery cell, a third battery cell, a fourth battery cell, a first anti-short circuit control circuit, a second anti-short circuit control circuit and a third anti-short circuit control circuit. The positive electrode of the first battery cell is connected to the input end of the first anti-short circuit control circuit, the output end of the first anti-short circuit control circuit is connected to the negative electrode of the second battery cell, the positive electrode of the second battery cell is connected to the input end of the second anti-short circuit control circuit, the output end of the second anti-short circuit control circuit is connected to the negative electrode of the third battery cell, the positive electrode of the third battery cell is connected to the input end of the third anti-short circuit control circuit, and the output end of the third anti-short circuit control circuit is connected to the negative electrode of the fourth battery cell.

[0023] That is to say, anti-short circuit control circuit 1, anti-short circuit control circuit 2 and anti-short circuit control circuit 3 are respectively added to the battery module series circuit 1, circuit 2 and circuit 3. When the negative electrode of B2 is short-circuited with the negative electrode of B1, the anti-short circuit control circuit 1 module detects an abnormally large current, and the anti-short circuit control circuit 1 will cut off the circuit 1 in the figure, and the positive and negative electrodes of the B1 battery cannot form a circuit, thereby avoiding the risk of positive and negative short circuit of B1; similarly, if the negative electrode of B3 is short-circuited with the negative electrode of B1, the anti-short circuit control circuit 1 or the anti-short circuit control circuit 2 detects an abnormally large current, and the anti-short circuit control circuit 1 will cut off the circuit 1 in the figure or the anti-short circuit control circuit 2 will cut off the circuit 2 in the figure, and the battery B1 It cannot form a short circuit loop with B2; when the negative electrode of B4 is short-circuited with the negative electrode of B1, the anti-short circuit control circuit 1, the anti-short circuit control circuit 2 or the anti-short circuit control circuit 3 detects an abnormally large current, the anti-short circuit control circuit 1 will cut off the loop 1 in the figure or the anti-short circuit control circuit 2 will cut off the loop 1 in the figure or the anti-short circuit control circuit 3 will cut off the loop 3 in the figure, and batteries B1 and B2 cannot form a short circuit loop; when the negative electrode of B3 is short-circuited with the negative electrode of B2, the anti-short circuit control circuit 2 will cut off the loop 2 in the figure, and B2 cannot form a short circuit loop; when the negative electrode of B4 is short-circuited with the negative electrode of B3, the anti-short circuit control circuit 3 will cut off the loop 3 in the figure, and B3 cannot form a short circuit loop.

[0024] As an embodiment, the acquisition unit 10 includes a first resistor R1 , and the first resistor R1 is a sampling resistor.

[0025] It should be noted that the voltage across the sampling resistor R1 is collected so as to determine whether there is abnormally large current discharge between the battery cells through the voltage difference across the two ends; if the voltage difference is large, it is determined that there is abnormally large current discharge between the battery cells, and if the voltage difference is small, it is determined that there is no abnormally large current discharge between the battery cells. As an embodiment, the subtraction unit 20 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a subtractor U1.

[0026] Among them, one end of the second resistor R2 is connected to one end of the first resistor R1, and one end of the first resistor R1 serves as the output end of the short-circuit prevention control circuit; one end of the third resistor R3 is connected to the other end of the second resistor R2, and the other end of the third resistor R3 is grounded; one end of the fourth resistor R4 is connected to the other end of the first resistor R1; one end of the fifth resistor R5 is connected to the other end of the fourth resistor R4; the first input end of the subtractor U1 is connected between the second resistor R2 and the third resistor R3, the second input end of the subtractor U1 is connected between the fourth resistor R4 and the fifth resistor R5, and the output end of the subtractor U1 is connected to the other end of the fifth resistor R5.

[0027] It should be noted that the voltage outputted from the output end of the subtractor U1 is used as the output voltage of the subtractor unit 20 , and the voltage outputted from the output end of the subtractor U1 is equal to the voltage difference across the sampling resistor R1 , that is, the output voltage is also positively correlated with the voltage difference across the sampling resistor R1 .

[0028] As an embodiment, the comparison unit 30 includes a comparator U2, a non-inverting input terminal of the comparator U2 is connected to the output terminal of the subtractor U1, and an inverting input terminal of the comparator U2 is connected to a preset voltage through a sixth resistor R6 and a seventh resistor R7.

[0029] It should be noted that the voltage outputted from the output terminal of the comparator U2 is used as a comparison voltage. If the non-inverting input terminal is greater than the inverting input terminal, the output comparison voltage is a high level. If the non-inverting input terminal is less than the inverting input terminal, the output comparison voltage is a low level.

[0030] As an embodiment, the switch control unit 40 includes a transistor Q2, an eighth resistor R8, a ninth resistor R9 and a MOS transistor Q1.

[0031] Among them, the base of the transistor Q2 is connected to the output end of the comparator U2, the collector of the transistor Q2 serves as the input end of the short-circuit prevention control circuit and has a first node A; one end of the eighth resistor R8 is connected to the first node A, the other end of the eighth resistor R8 is connected to the emitter of the transistor Q2, and has a second node B; one end of the ninth resistor R9 is connected to the second node B, and the other end of the ninth resistor R9 is grounded; the source of the MOS tube Q1 is connected to the first node A, the gate of the MOS tube Q1 is connected to the second node B, and is connected to the ground through the second capacitor C2, and the drain of the MOS tube Q1 is connected to the other end of the first resistor R1.

[0032] It should be noted that when the battery module is outputting normally, the voltage difference of the sampling resistor R1 is very small, the output voltage of the subtractor U1 is very small, the comparator U2 outputs a low level, the transistor Q2 is disconnected, the MOS tube Q1 is turned on, and the system works normally; when a short circuit occurs between the battery cells, due to the large current passing through the first resistor R1, the voltage difference across the first resistor R1 is very large, the output voltage of the subtractor U1 is very large, the comparator U2 outputs a high level, the transistor Q2 is turned on, the MOS tube Q1 is disconnected, and the system loses power.

[0033] In summary, according to the short-circuit prevention control circuit of the battery module proposed by the utility model, any two adjacent battery cells in the battery module are connected through the short-circuit prevention control circuit, wherein the short-circuit prevention control circuit includes: a collection unit, the collection unit is used to collect the voltage signal pair at both ends; a subtraction unit, the first input end of the subtraction unit is connected to one end of the collection unit, the second input end of the subtraction unit is connected to the other end of the collection unit, the subtraction unit performs a subtraction operation on the voltage signal pair to obtain an output voltage; a comparison unit, the first input end of the comparison unit is connected to the output end of the subtraction unit, the second input end of the comparison unit is connected to a preset voltage, the comparison unit compares the output voltage with the preset voltage to obtain an output comparison voltage; a switch control unit, the input end of the switch control unit is connected to the output end of the comparison unit, the switch control unit controls the conduction relationship between any two adjacent battery cells according to the comparison voltage; thereby, when it is detected that the battery has an abnormally large current discharge, the protection measures are immediately started to limit the battery discharge, and the short-circuit prevention control circuit not only has a fast response speed, but also can adjust and set the abnormal current size.

[0034] The embodiment of the utility model further provides a battery module, which includes the above-mentioned short-circuit protection control circuit of the battery module.

[0035] According to the battery module proposed by the utility model, by adding an anti-short circuit control circuit between any two adjacent battery cells, when an abnormally large current discharge of the battery is detected, protection measures are immediately activated to limit the battery discharge. The anti-short circuit control circuit not only has a fast response speed, but also can adjust and set the abnormal current size.

[0036] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like 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 a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0040] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0041] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A short circuit prevention control circuit for a battery module, characterized in that: Any two adjacent battery cells in the battery module are connected via the anti-short circuit control circuit, wherein the anti-short circuit control circuit includes: A collection unit, the collection unit is used to collect the voltage signal pair at both ends; A subtraction unit, wherein a first input end of the subtraction unit is connected to one end of the acquisition unit, a second input end of the subtraction unit is connected to the other end of the acquisition unit, and the subtraction unit performs a subtraction operation on the voltage signal pair to obtain an output voltage; A comparison unit, wherein a first input terminal of the comparison unit is connected to the output terminal of the subtraction unit, a second input terminal of the comparison unit is connected to a preset voltage, and the comparison unit compares the output voltage with the preset voltage to obtain an output comparison voltage; A switch control unit, wherein an input end of the switch control unit is connected to an output end of the comparison unit, and the switch control unit controls the conduction relationship between any two adjacent battery cells according to the comparison voltage.

2. The short-circuit prevention control circuit of the battery module according to claim 1, characterized in that: The battery module includes a first battery cell, a second battery cell, a third battery cell, a fourth battery cell, a first anti-short circuit control circuit, a second anti-short circuit control circuit and a third anti-short circuit control circuit. The positive electrode of the first battery cell is connected to the input end of the first anti-short circuit control circuit, the output end of the first anti-short circuit control circuit is connected to the negative electrode of the second battery cell, the positive electrode of the second battery cell is connected to the input end of the second anti-short circuit control circuit, the output end of the second anti-short circuit control circuit is connected to the negative electrode of the third battery cell, the positive electrode of the third battery cell is connected to the input end of the third anti-short circuit control circuit, and the output end of the third anti-short circuit control circuit is connected to the negative electrode of the fourth battery cell.

3. The short-circuit prevention control circuit of the battery module according to claim 1, characterized in that: The acquisition unit includes a first resistor, which is a sampling resistor.

4. The short-circuit prevention control circuit of the battery module according to claim 3, characterized in that: The subtraction unit comprises: a second resistor, one end of which is connected to one end of the first resistor, and one end of the first resistor serves as an output end of the short-circuit prevention control circuit; a third resistor, one end of the third resistor being connected to the other end of the second resistor, and the other end of the third resistor being grounded; a fourth resistor, one end of the fourth resistor being connected to the other end of the first resistor; a fifth resistor, one end of the fifth resistor being connected to the other end of the fourth resistor; A subtractor, wherein a first input terminal of the subtractor is connected between the second resistor and the third resistor, a second input terminal of the subtractor is connected between the fourth resistor and the fifth resistor, and an output terminal of the subtractor is connected to the other end of the fifth resistor.

5. The short-circuit prevention control circuit of the battery module as claimed in claim 4, characterized in that: The comparison unit comprises: A comparator, wherein the non-inverting input terminal of the comparator is connected to the output terminal of the subtractor, and the inverting input terminal of the comparator is connected to a preset voltage through a sixth resistor and a seventh resistor.

6. The short-circuit prevention control circuit of the battery module according to claim 5, characterized in that: The switch control unit comprises: A transistor, the base of which is connected to the output end of the comparator, the collector of which serves as the input end of the short-circuit prevention control circuit and has a first node; an eighth resistor, one end of the eighth resistor being connected to the first node, the other end of the eighth resistor being connected to the emitter of the transistor, and having a second node; a ninth resistor, one end of the ninth resistor being connected to the second node, and the other end of the ninth resistor being grounded; A MOS tube, wherein the source of the MOS tube is connected to the first node, the gate of the MOS tube is connected to the second node and connected to the ground through a second capacitor, and the drain of the MOS tube is connected to the other end of the first resistor.

7. A battery module, characterized in that: A short-circuit prevention control circuit comprising a battery module as described in any one of claims 1 to 6.

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