Battery protection circuit, power battery and vehicle

Abstract

The utility model relates to the technical field of circuit design, and particularly discloses a battery protection circuit, a power battery and a vehicle. The battery comprises a first battery pack and a second battery pack, the protection circuit of the battery comprises an outgoing line and a safety device, the second battery pack is electrically connected with the first battery pack, the outgoing line is connected between the second battery pack and the first battery pack, and the safety device is arranged on the outgoing line. Safety monitoring can be carried out on the battery pack in the battery through the safety device, and the service life of the battery is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of circuit design technology, and in particular to a battery protection circuit, a power battery, and a vehicle. Background Technology

[0002] With the development of battery technology, new energy vehicles are gradually being widely used. As the core power source in new energy vehicles, the safety of power batteries is of utmost importance.

[0003] In related technologies, the safety of the entire battery is generally monitored directly. If a battery pack in the battery is short-circuited, it cannot respond in time, thus failing to protect the battery in time and reducing the battery's lifespan. Utility Model Content

[0004] The present invention aims to at least partially solve one of the technical problems in the related art. Therefore, the first objective of this invention is to provide a battery protection circuit that can promptly protect the battery pack within the battery, thereby improving the battery's lifespan.

[0005] The second objective of this invention is to propose a power battery.

[0006] The third objective of this utility model is to provide a vehicle.

[0007] To achieve the above objectives, a first aspect of this utility model provides a battery protection circuit. The battery includes a first battery pack and a second battery pack, which are electrically connected to the first battery pack. The protection circuit includes: a lead wire connected between the second battery pack and the first battery pack; and a fuse device disposed on the lead wire.

[0008] The battery protection circuit in this embodiment includes lead wires and fuses. The lead wires are led out from the connection between the first and second battery packs, and the fuses are installed on the lead wires, thereby enabling timely protection of the battery packs and improving the battery's lifespan.

[0009] In some examples of this utility model, the end of the first battery pack that is not connected to the second battery pack is connected to a first battery pack fuse device, and the end of the second battery pack that is not connected to the first battery pack is connected to a second battery pack fuse device.

[0010] In some examples of this invention, the fuse is designed to be triggered when the first battery pack fuse and / or the second battery pack fuse fails.

[0011] In some examples of this utility model, the protection circuit further includes a voltage divider device, which is connected in series with the fuse device and is used to divide the voltage of the fuse device.

[0012] In some examples of this invention, the voltage divider device is a resistor or a voltage divider contactor.

[0013] In some examples of this invention, the fuse device and the voltage divider device are integrated into a single component.

[0014] In some examples of this utility model, at least one of the first battery pack fuse, the second battery pack fuse, and the fuse is a resettable fuse.

[0015] In some examples of this utility model, the resettable fuse includes a current-sensing fuse, a first excitation fuse, a second excitation fuse, a first excitation source, and a second excitation source. The current-sensing fuse, the first excitation fuse, and the second excitation fuse are connected in series. The first excitation source is connected in parallel with the current-sensing fuse and is used to control the first excitation fuse to be in a closed state when the current-sensing fuse blows. The second excitation source is connected to the output terminal of an external signal and is used to control the second excitation fuse to be in a closed state when the external signal is a closed signal.

[0016] In some examples of this utility model, the positive terminal of the battery is led out to a positive input terminal and a positive output terminal, and the negative terminal of the battery is led out to a negative input terminal and a negative output terminal.

[0017] In some examples of this utility model, the positive output terminal, the negative output terminal, and the lead wire are used to connect to an external load so that the battery supplies power to the external load; the positive input terminal and the negative input terminal are used to connect to an external charging device so that the battery receives charging from the external charging device.

[0018] To achieve the above objectives, a second aspect of this utility model provides a power battery, which includes the protection circuit of the battery described in the above embodiment, so as to protect the power battery through the protection circuit.

[0019] The power battery of this utility model embodiment can protect the battery pack in the power battery through the protection circuit of the battery in the above embodiment, thereby improving the service life of the power battery.

[0020] To achieve the above objectives, a third aspect of this utility model provides a vehicle, which includes the power battery described in the above embodiments.

[0021] The vehicle of this utility model embodiment, through the power battery of the above embodiment, can protect the battery pack in the power battery and improve the service life of the power battery.

[0022] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the application scenario of the battery in one embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the battery protection circuit structure in one embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of a resettable fuse device in one embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the connection of the fuse device in one embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of a fuse device in one embodiment of the present invention;

[0028] Figure 6 This is a structural block diagram of the power battery according to an embodiment of the present utility model;

[0029] Figure 7 This is a structural block diagram of a vehicle according to an embodiment of the present utility model. Detailed Implementation

[0030] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0031] The following description, with reference to the accompanying drawings, describes a battery protection circuit, a power battery, and a vehicle according to embodiments of the present invention.

[0032] In low-temperature environments (such as below -10 degrees Celsius), both the discharge and charging performance of a battery are significantly affected. This can range from minor impacts on battery life to serious issues like lithium dendrites piercing the battery separator, causing short circuits, and even battery fires. The battery in this embodiment utilizes self-heating via lead wires to prevent these problems. Specifically... Figure 1As shown, pulse signals control the first switch K1 and the second switch K2 respectively. When the first switch K1 is closed and the second switch K2 is open, the first battery pack 11 charges the inductor L. Then, by switching the switches, i.e., the first switch K1 is open and the second switch K2 is closed, the energy in the inductor L can charge the second battery pack 12. Conversely, the second battery pack 12 can also charge the inductor L, which in turn charges the first battery pack 11 with its stored energy. Through the charging and discharging process between the first battery pack 11 and the second battery pack 12, the internal resistance of the batteries generates heat, allowing the batteries to operate normally in low-temperature environments.

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

[0034] like Figure 2 As shown, this utility model divides the battery into two half-packs, namely a first battery pack 11 and a second battery pack 12, which are connected in series. The first battery pack 11 can be the positive half-pack, and the second battery pack 12 can be the negative half-pack. The battery protection circuit 1 includes a lead wire and a fuse 13. The lead wire can be the battery's neutral (N) wire, extending from the connection between the first battery pack 11 and the second battery pack 12. The fuse 13 is located on the lead wire. It should be noted that when outputting through the first battery pack 11, the lead wire can serve as the negative terminal of the first battery pack 11; when outputting through the second battery pack 12, the lead wire can serve as the positive terminal of the second battery pack 12. Therefore, during the battery's self-heating process, the fuse 13 can protect both the first battery pack 11 and the second battery pack 12. If one battery pack malfunctions, the fuse 13 can respond promptly to protect the entire battery.

[0035] To further improve battery safety performance, see [link / reference]. Figure 1 or Figure 2 The protection circuit 1 of the battery of this utility model is further provided with a first battery pack fuse 14 corresponding to the first battery pack 11 and a second battery pack fuse 15 corresponding to the second battery pack 12. The first battery pack fuse 14 is connected to the end of the first battery pack 11 that is not connected to the second battery pack 12, and the second battery pack fuse 15 is connected to the end of the second battery pack 12 that is not connected to the first battery pack 11.

[0036] Specifically, the first battery pack fuse 14 and the second battery pack fuse 15 can work in conjunction with fuse 13 to further protect the battery. For example, during the battery self-heating process, when the first battery pack 11 discharges to the inductor or the inductor charges the first battery pack 11, the charging and discharging circuit of the first battery pack 11 includes both the first battery pack fuse 14 and fuse 13. When a fault occurs in this charging and discharging circuit, either the first battery pack fuse 14 or fuse 13 will respond, thus protecting the battery. Similarly, the second battery pack fuse 15 and fuse 13 can also respond to faults occurring in the charging and discharging circuit of the second battery pack 12, thereby protecting the battery.

[0037] In addition, the first battery pack fuse 14 and the second battery pack fuse 15 in this embodiment can also protect the entire battery's charging and discharging circuit. Taking the example that both the first battery pack fuse 14 and the second battery pack fuse 15 are fuses, when a short circuit or other fault occurs in the entire battery's charging and discharging circuit, causing the circuit to generate a large amount of heat, the fuse can break the circuit by melting, thereby protecting the battery. It should be noted that if only the first battery pack fuse 14 and the second battery pack fuse 15 are provided, then during the battery's self-heating process, because the temperature range in which the fuse can work normally is small, the detection of the fuse will be affected in low-temperature environments, and it cannot complete the melting response very sensitively. Therefore, in this embodiment, a fuse 13 is provided on the battery's N line, which can fully protect the battery. Furthermore, the fuse 13 in this embodiment can be a resettable fuse, which increases the temperature range in which the fuse 13 can work normally, ensuring that the battery can be protected in low-temperature environments.

[0038] More specifically, the fuse 13 can cut off power in a faulty environment, and when the faulty environment is cleared, the fuse 13 can return to its original state, ensuring that the circuit can be used normally. It can automatically resume use without manual replacement, which is very convenient, reduces battery maintenance costs, and is suitable for vehicles that frequently generate large pulses.

[0039] In some embodiments, both the first battery pack fuse 14 and the second battery pack fuse 15 may use this type of resettable fuse. Optionally, the resettable fuse may be a ceramic PTC (Positive Temperature Coefficient), a polymer PTC, etc.

[0040] More specifically, such as Figure 3As shown, the resettable fuse includes a current-detecting fuse 31, a first excitation fuse 32, a second excitation fuse 33, a first excitation source 34, and a second excitation source 35. The current-detecting fuse 31, the first excitation fuse 32, and the second excitation fuse 33 are connected in series. The first excitation source 34 is connected in parallel with the current-detecting fuse 31 and is used to control the first excitation fuse 32 to be in the off state when the current-detecting fuse 31 blows. The second excitation source 35 is connected to the output terminal of an external signal and is used to control the second excitation fuse 33 to be in the off state when the external signal is an off signal.

[0041] Specifically, see Figure 3 The main circuit is the wiring for the resettable fuses. For example, for fuse 13, the main circuit is the lead wire; for the first battery pack fuse 14, the main circuit is the wiring from the positive terminal of the battery; and for the second battery pack fuse 15, the main circuit is the wiring from the negative terminal of the battery. A current-detecting fuse 31, a first excitation fuse 32, and a second excitation fuse 33 are connected in series in the main circuit. The current-detecting fuse 31 is also connected in parallel with a first excitation source 34. When a circuit fault occurs and the current-detecting fuse 31 blows, the voltage across the first excitation source 34 increases, triggering the first excitation source 34 to send a control signal to the first excitation fuse 32, controlling the first excitation fuse 32 to be in the off state, thus protecting the circuit. When the fault is cleared, the current-detecting fuse 31 can be restored to the connected state, the voltage across the first excitation source 34 will decrease, so the first excitation fuse 32 also returns to the connected state, the circuit can operate normally, and the battery can be used normally. As can be seen, the resettable fuse of this patent can automatically trigger to protect the circuit when a fault occurs, and can also automatically restore the circuit to normal use after the fault is eliminated, without the need for human intervention, and has a high degree of automation.

[0042] Furthermore, the second excitation source 35 in the resettable fuse can receive external signals. These external signals can be actively sent by maintenance personnel. For example, when repairing the circuit, to ensure operational safety, maintenance personnel can first send a shutdown signal to the second excitation source 35. After receiving the shutdown signal, the second excitation source 35 can control the second excitation fuse 33 to be in the off state, thus breaking the main circuit. The second excitation source 35 is directly connected to the output terminal of the external signal without any other intermediate components, ensuring that the external signal can directly perform detection and control. A component 36 is also provided between the current detection fuse 31 and the first excitation source 34. This component 36 can provide voltage division protection for the first excitation source 34, preventing the surge generated after the current detection fuse 31 blows or connects from damaging the first excitation source 34, thereby improving the service life of the first excitation source 34. In addition, in this embodiment, the trigger signals between self-triggered and externally triggered circuits are completely isolated to prevent interference, ensuring that both self-triggered and externally triggered circuits can accurately protect the circuit.

[0043] See Figure 4 The protection circuit 1 also includes a voltage divider device 16, which is connected in series with the fuse device 13 and is used to divide the voltage of the fuse device 13.

[0044] Specifically, to ensure the proper functioning of the fuse 13 and prevent misjudgments, this embodiment also includes a voltage divider 16 connected in series with the fuse 13 to perform voltage division on the fuse 13, such as... Figure 4 As shown, one end of the voltage divider 16 is connected to the positive terminal of the second battery pack 12 via a copper busbar, and the other end is connected to one end of the fuse 13. The other end of the fuse 13 can be connected to the middle of an external three-pin connector 20, allowing the external load to be powered through the three-pin connector 20. It should be noted that in this embodiment, the external connector of the fuse 13 is as follows... Figure 5 As shown, copper busbars are used for connection to ensure conductivity. Furthermore, to save space, the fuse 13 and voltage divider 16 can be integrated into a single component. Specifically, one end of the fuse 13 is connected to one end of the voltage divider 16, and the connected fuse 13 and voltage divider 16 are then encapsulated in a housing as a single component. The other ends of the fuse 13 and the voltage divider 16 serve as the two ends of this component, used to connect to the lead wires. Integrating the fuse 13 and voltage divider 16 increases circuit wiring space and enables integrated control, allowing the battery to adapt to more application environments.

[0045] In some examples, the voltage divider 16 can be a resistor or a voltage divider contactor to achieve the voltage division function. It should be noted that if the voltage in the circuit is sufficient for the fuse 13 to function normally, then the voltage divider 16 is unnecessary. Furthermore, if the voltage divider 16 in this embodiment is a contactor, it can also possess the basic functions of a contactor, specifically, the circuit can be shut off by controlling the contactor to be in a closed or open state. It is understood that in this embodiment, when the battery is not faulty, the contactor is in a normally closed state; when the battery is faulty, the contactor is in a normally open state. When the contactor is in the normally open state, maintenance personnel can inspect the circuit, ensuring their personal safety and preventing electric shock.

[0046] In some embodiments, when the first battery pack fuse 14 and / or the second battery pack fuse 15 fail, the fuse 13 is triggered to operate.

[0047] Specifically, when the first battery pack fuse 14 and the second battery pack fuse 15 are functioning normally, fuse 13 may not be in operation because the first and second battery pack fuses 14 and 15 can protect the battery. When at least one of the first and second battery pack fuses 14 or 15 fails, for example, when the ambient temperature of the battery is outside the normal operating temperature range of the fuse (such as a temperature of -40 degrees Celsius), the fuse may not respond sensitively to the heat generated by the short circuit and melt. In this case, fuse 13 can be triggered to operate, preventing the first and second battery pack fuses 14 and 15 from failing to melt due to special operating conditions. This embodiment, through redundant design of the fuses, can further improve battery safety and prevent battery accidents.

[0048] In some embodiments of this utility model, such as Figure 2 As shown, the positive terminal of the battery has a positive input terminal and a positive output terminal, and the negative terminal has a negative input terminal and a negative output terminal. The positive output terminal, negative output terminal, and leads are used to connect to an external load so that the battery can supply power to the external load; the positive input terminal and negative input terminal are used to connect to an external charging device so that the battery can receive charging from the external charging device.

[0049] Specifically, in this embodiment, the battery serves as the vehicle's power battery. Both the positive output and positive input terminals are led out from the positive terminal of the battery, and the negative output and negative input terminals are also led out from the negative terminal. Furthermore, a neutral (N) line is led out between the first battery pack 11 and the second battery pack 12. This N line can be connected to a fuse device 13, a voltage divider device 16, etc. The positive and negative input terminals can be connected to the vehicle's charging interface, allowing an external charging station to charge the battery when connected to the vehicle. The fuse device 13 on the N line can monitor the battery's self-heating circuit in real time during self-heating. If a fault occurs, it responds promptly to protect the battery, reduce battery wear rate, and lower battery maintenance costs.

[0050] In summary, the battery protection circuit in this embodiment of the present invention can protect the battery pack in the battery, improve the battery's service life, enhance the battery's environmental adaptability, and reduce the battery's maintenance costs.

[0051] Figure 6 This is a structural block diagram of the power battery according to an embodiment of the present utility model.

[0052] Furthermore, such as Figure 6 As shown, this utility model proposes a power battery 40, which includes the protection circuit 1 of the battery in the above embodiment, so as to protect the power battery 40 through the protection circuit 1.

[0053] The power battery of this utility model embodiment can protect the battery pack in the power battery through the protection circuit of the battery in the above embodiment, thereby improving the service life of the power battery.

[0054] Figure 7 This is a structural block diagram of a vehicle according to an embodiment of the present utility model.

[0055] Furthermore, such as Figure 7 As shown, the present invention proposes a vehicle 50, which includes the power battery 40 of the above embodiment.

[0056] The vehicle of this utility model embodiment, through the power battery of the above embodiment, can protect the battery pack in the power battery and improve the service life of the power battery.

[0057] Furthermore, the other components and functions of the vehicle in this embodiment are known to those skilled in the art, and will not be described in detail here to reduce redundancy.

[0058] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0059] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0060] Furthermore, the terms "first," "second," etc., used in the embodiments of this utility model are for descriptive purposes only and should not be construed as indicating or implying relative importance, or implicitly specifying the number of technical features indicated in this embodiment. Therefore, features defined with terms such as "first" and "second" in the embodiments of this utility model can explicitly or implicitly indicate that the embodiment includes at least one of those features. In the description of this utility model, the word "multiple" means at least two or more, such as two, three, four, etc., unless otherwise explicitly specified in the embodiments.

[0061] In this utility model, unless otherwise explicitly specified or limited in the embodiments, the terms "installation," "connection," "joining," and "fixing" appearing in the embodiments should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can also be a mechanical connection, an electrical connection, etc. Of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific implementation.

[0062] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0063] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A battery protection circuit (1), characterized in that, The battery includes a first battery pack (11) and a second battery pack (12), the second battery pack (12) being electrically connected to the first battery pack (11), and the protection circuit (1) including: Lead wires are connected between the second battery pack (12) and the first battery pack (11); A fuse (13) is disposed on the lead-out line.

2. The battery protection circuit (1) according to claim 1, characterized in that, The end of the first battery pack (11) that is not connected to the second battery pack (12) is connected to a first battery pack fuse device (14), and the end of the second battery pack (12) that is not connected to the first battery pack (11) is connected to a second battery pack fuse device (15).

3. The battery protection circuit (1) according to claim 2, characterized in that, The fuse is to be triggered when the first battery pack fuse (14) and / or the second battery pack fuse (15) fails.

4. The battery protection circuit (1) according to claim 2, characterized in that, The protection circuit (1) further includes: Voltage divider device (16), which is connected in series with fuse device (13) for voltage division of fuse device (13).

5. The battery protection circuit (1) according to claim 4, characterized in that, The voltage divider device (16) is a resistor or a voltage divider contactor.

6. The battery protection circuit (1) according to claim 4, characterized in that, The fuse device (13) and the voltage divider device (16) are integrated into one component.

7. The battery protection circuit (1) according to claim 6, characterized in that, At least one of the first battery pack fuse (14), the second battery pack fuse (15), and the fuse (13) is a resettable fuse.

8. The battery protection circuit (1) according to claim 7, characterized in that, The resettable fuse includes a current-detecting fuse (31), a first excitation fuse (32), a second excitation fuse (33), a first excitation source (34), and a second excitation source (35). The current-detecting fuse (31), the first excitation fuse (32), and the second excitation fuse (33) are connected in series. The first excitation source (34) is connected in parallel with the current-detecting fuse (31) and is used to control the first excitation fuse (32) to be in the off state when the current-detecting fuse (31) blows. The second excitation source (35) is connected to the output terminal of an external signal and is used to control the second excitation fuse (33) to be in the off state when the external signal is an off signal.

9. The battery protection circuit (1) according to claim 1, characterized in that, The positive terminal of the battery has a positive input terminal and a positive output terminal, and the negative terminal of the battery has a negative input terminal and a negative output terminal. The positive output terminal, the negative output terminal, and the lead wire are used to connect to an external load so that the battery can supply power to the external load; the positive input terminal and the negative input terminal are used to connect to an external charging device so that the battery can receive charging from the external charging device.

10. A power battery (40), characterized in that, The power battery (40) includes a protection circuit (1) of any one of claims 1-9 to protect the power battery (40) through the protection circuit (1).

11. A vehicle (50), characterized in that, The vehicle (50) includes the power battery (40) as described in claim 10.

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