Electrostatic protection circuit, battery management equipment, battery pack and electric equipment

Abstract

The embodiment of the invention provides an electrostatic protection circuit, battery management equipment, a battery pack and electric equipment, and the electrostatic protection circuit comprises a first electrostatic protection unit which is configured to be electrically connected between a positive electrode output terminal and a negative electrode of a battery module, and the first electrostatic protection unit comprises at least one capacitor; and / or the second electrostatic protection unit is configured to be electrically connected between the negative electrode output terminal and the negative electrode of the battery module, and the second electrostatic protection unit comprises at least one capacitor.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to an electrostatic protection circuit, a battery management device, a battery pack and an electrical device. Background Art

[0002] In current battery management equipment, static electricity may be generated due to friction, induction, conduction and other mechanisms when handling and moving batteries, cables and related components. Static electricity may cause battery damage or safety accidents, causing harm to the human body and equipment, so the generation and management of static electricity is crucial to battery safety. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide an electrostatic protection circuit, a battery management device, a battery pack and an electrical device to reduce the cost of electrostatic protection. The specific technical solution is as follows:

[0004] In a first aspect, an embodiment of the present application provides an electrostatic protection circuit, comprising: a first electrostatic protection unit, configured to be electrically connected between a positive output terminal and a negative pole of a battery module, the first electrostatic protection unit comprising at least one capacitor; and / or, a second electrostatic protection unit, configured to be electrically connected between a negative output terminal and the negative pole of the battery module, the second electrostatic protection unit comprising at least one capacitor.

[0005] In a possible embodiment, the first electrostatic protection unit includes a plurality of capacitors, each of which is connected in series; and / or the second electrostatic protection unit includes a plurality of capacitors, each of which is connected in series.

[0006] In a possible embodiment, it includes: a third electrostatic protection unit, a first end of the third electrostatic protection unit is electrically connected to the first end of the first electrostatic protection unit, the first end of the third electrostatic protection unit is also configured to be electrically connected to the positive output terminal, and the second end of the third electrostatic protection unit is configured to be electrically connected to the positive electrode of the battery module; a fourth electrostatic protection unit, a first end of the fourth electrostatic protection unit is electrically connected to the second end of the third electrostatic protection unit, the first end of the fourth electrostatic protection unit is also configured to be electrically connected to the positive electrode of the battery module, and the second end of the fourth electrostatic protection unit is configured to be electrically connected to the negative electrode of the battery module; the third electrostatic protection unit includes at least one capacitor, and the fourth electrostatic protection unit includes at least one capacitor.

[0007] In a possible embodiment, the third electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series; the fourth electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series.

[0008] In a possible embodiment, it includes: a fifth electrostatic protection unit, wherein the first end of the fifth electrostatic protection unit is electrically connected to the first end of the first electrostatic protection unit, the first end of the fifth electrostatic protection unit is also configured to be electrically connected to the positive output terminal, and the second end of the fifth electrostatic protection unit is configured to be electrically connected to the negative output terminal; the fifth electrostatic protection unit includes at least one capacitor.

[0009] In a possible embodiment, the electrostatic protection circuit includes the first electrostatic protection unit and the second electrostatic protection unit, the second end of the fifth electrostatic protection unit is electrically connected to the first end of the second electrostatic protection unit, and the second end of the second electrostatic protection unit is configured to be electrically connected to the negative pole of the battery module.

[0010] In a possible embodiment, the fifth electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series.

[0011] In a second aspect, an embodiment of the present application provides a battery management device, comprising the electrostatic protection circuit described in any one of the above-mentioned first aspects.

[0012] In a third aspect, an embodiment of the present application provides a battery pack, comprising a battery module, a connector, and a battery management device as described in the second aspect above, wherein the battery module comprises a plurality of battery cells; the connector comprises a positive output terminal and a negative output terminal; and the battery management device is electrically connected to the battery module and the connector, respectively.

[0013] In a possible embodiment, the negative electrode of the battery module, the positive output terminal, and the negative output terminal are respectively coupled to the ground.

[0014] In a fourth aspect, an embodiment of the present application provides an electrical device, comprising a load and a battery pack as described in any one of the third aspects above.

[0015] Beneficial effects of the embodiments of the present application:

[0016] The embodiments of the present application provide an electrostatic protection circuit, a battery management device, a battery pack, and an electrical device, wherein the electrostatic protection circuit includes: a first electrostatic protection unit, configured to be electrically connected between the positive output terminal and the negative electrode of the battery module, and the first electrostatic protection unit includes at least one capacitor; and / or, a second electrostatic protection unit, configured to be electrically connected between the negative output terminal and the negative electrode of the battery module, and the second electrostatic protection unit includes at least one capacitor. In the present application, the anti-static function is achieved by setting a capacitor to couple static electricity to the ground. Compared with the related art that uses multiple groups of ESD (Electro-Static discharge, which can also represent equipment used for electrostatic protection, called electrostatic resistors) or TVS (Transient Voltage Suppressor, transient voltage suppression diodes) to achieve electrostatic protection, the circuit is simple and the cost of electrostatic protection is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application and do not provide a restrictive understanding and interpretation of the present application.

[0018] Figure 1a A schematic diagram of the first structure of the electrostatic protection circuit provided in the embodiment of the present application;

[0019] Figure 1b A second structural schematic diagram of the electrostatic protection circuit provided in an embodiment of the present application;

[0020] Figure 1c A third structural schematic diagram of the electrostatic protection circuit provided in an embodiment of the present application;

[0021] Figure 2 A schematic diagram of electrostatic discharge of an electrostatic protection circuit provided in an embodiment of the present application;

[0022] Figure 3a A fourth structural schematic diagram of the electrostatic protection circuit provided in an embodiment of the present application;

[0023] Figure 3b A fifth structural schematic diagram of the electrostatic protection circuit provided in the embodiment of the present application;

[0024] Figure 3c A sixth structural schematic diagram of an electrostatic protection circuit provided in an embodiment of the present application;

[0025] Figure 4 A seventh structural schematic diagram of an electrostatic protection circuit provided in an embodiment of the present application;

[0026] Figure 5 An eighth structural schematic diagram of an electrostatic protection circuit provided in an embodiment of the present application;

[0027] Figure 6 A ninth structural schematic diagram of an electrostatic protection circuit provided in an embodiment of the present application;

[0028] Figure 7 A schematic diagram of the first structure of a battery management device provided in an embodiment of the present application;

[0029] Figure 8 A second structural schematic diagram of a battery management device provided in an embodiment of the present application;

[0030] Fig. 9 A schematic diagram of the structure of a battery pack provided in an embodiment of the present application;

[0031] Fig.10 A schematic diagram of the structure of an electrical device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and in detail describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following specific embodiments are exemplary rather than limiting, and are intended to provide a basic understanding of the present application, and are not intended to confirm the key or decisive elements of the present invention or to limit the scope of protection.

[0033] In the related technology, battery management equipment uses ESD (Electro-Static discharge, which can also refer to equipment used for electrostatic protection, called electrostatic resistor) or TVS (Transient Voltage Suppressor) solutions to achieve electrostatic protection. TVS and ESD work in the same way, by quickly responding to and absorbing surge energy, it limits excessive voltage to an acceptable range, thereby protecting electronic equipment from damage. ESD is mainly used to prevent static electricity, which requires a low capacitance value, while TVS has a relatively high capacitance value. Since TVS and ESD devices are relatively expensive and have the risk of failure, they may cause the battery management equipment to heat up, requiring additional insurance devices (such as fuses), further increasing the cost of the above-mentioned electrostatic protection solutions.

[0034] When designing the board layers of a printed circuit board (PCB), the anti-static ability is enhanced by increasing the number of PCB layers and the grounding area. For example, compared with a two-layer board (the layout of the circuit of the two-layer board is limited to its two surfaces), the design of a four-layer board (the top and bottom layers are signal layers, and the middle two layers are power layers and ground layers) effectively increases the grounding area, thereby enhancing the electrostatic protection ability, but increasing the number of PCB layers will increase the cost and size accordingly.

[0035] In the present application, as a specific example, the battery management device is a printed circuit board, and the battery management device is provided with a chip (also called a microcontroller unit), a capacitor, a resistor, a switch, a positive output terminal P+, a negative output terminal P- and other components. In the process of realizing the present application, the inventor found that there is a high-voltage electrical gap between the positive output terminal P+, the negative output terminal P- and the negative electrode B- of the battery module in the PCB, and in the PCB design, the positive output terminal P+ and the negative electrode B- of the battery module are in different networks, and the negative output terminal P- and the negative electrode B- of the battery module are in different networks. The above three terminals have no direct association design from the circuit connection and the PCB design layout. The positive output terminal P+ is coupled with the negative electrode B- of the battery module, and the negative output terminal P- is coupled with the negative electrode B- of the battery module, which is an unconventional design of the battery management device in the circuit design.

[0036] In order to improve the above problems, the inventors further discovered that the network where the negative electrode B- of the battery module on the PCB is located has a large area of ​​copper plating, and the network where the positive output terminal P+ and the negative output terminal P- are located is an external port electrically connected to an external device, and the copper plating area is small. During the electrostatic test or actual use of the battery management device, the external port is prone to generate static electricity, which is coupled to other circuits in the battery management device through the positive output terminal P+ and the negative output terminal P-, which may cause risks such as chip damage and capacitor overvoltage breakdown. Therefore, it is necessary to quickly discharge the static electricity on the positive output terminal P+ and the negative output terminal P- to reduce the failure risk of electronic components on the PCB.

[0037] Because the network where the negative electrode B- of the battery module is located has a large area of ​​copper plating, a low-impedance electrostatic discharge path is provided, and the above network serves as a floating ground for the battery management device (floating ground means that the ground of the circuit is not connected to the earth by a conductor). When solving the technical problem that electrostatic signals are coupled to other circuits in a battery management device through the positive output terminal P+ and the negative output terminal P-, causing interference or impact on other circuits or electronic components, the inventor utilized the technical principle that there is a potential difference between the network where the positive output terminal P+ is located and the network where the negative pole B- of the battery module is located, and there is a potential difference between the network where the negative output terminal P- is located and the network where the negative pole B- of the battery module is located, and the voltage across the capacitor cannot change suddenly. A capacitor is set between the positive output terminal P+ and the negative output terminal P-, a capacitor is set between the positive output terminal P+ and the negative pole B- of the battery module, and a capacitor is set between the negative output terminal P- and the negative pole B- of the battery module. The static electricity on the positive output terminal P+ and the negative output terminal P- is quickly transferred to the floating ground through the capacitor, thereby achieving electrostatic discharge and reducing the risk of electrostatic signals flowing into other circuits.

[0038] Based on the above design concept, the present application provides an electrostatic protection circuit 1, see Figure 1a , Figure 1b and Figure 1c , the electrostatic protection circuit 1 is arranged on the battery management device, including a first electrostatic protection unit 11 and / or a second electrostatic protection unit 12. The battery management device is electrically connected to the positive electrode B+ and the negative electrode B- of the battery module through an electrical connector (such as a bus), and is electrically connected to the first connector (such as an aviation plug, not shown) on the battery pack through a power harness. The first connector includes a positive output terminal P+ and a negative output terminal P-. The first connector is used for the second connector on an external electrical device, and the second connector is provided with a positive terminal and a negative terminal. The positive output terminal P+ is connected to the positive terminal on the second connector, and the negative output terminal P- is connected to the negative terminal on the second connector, so as to realize the electrical connection between the battery pack and the electrical device. As an example of the present application, the battery module is in a discharge mode, and the battery module supplies power to the load of the electrical device (such as a motor), and the electrical device is an electric vehicle (such as an electric bicycle, an electric motorcycle, etc.).

[0039] In other embodiments of the present application, electrical equipment includes: power tools (including garden power tools and household power tools, such as electric lawn mowers, electric drills, etc.), electric cleaning tools (such as sweepers, vacuum cleaners, etc.), aircraft (such as agricultural drones, consumer drones), energy storage systems (such as household energy storage systems, commercial energy storage systems, industrial energy storage systems, uninterruptible power supplies UPS, etc., the full name of uninterruptible power supply UPS is Uninterruptible Power Supply).

[0040] One end of the first electrostatic protection unit 11 is coupled to the negative electrode B- of the battery module, and the other end of the first electrostatic protection unit 11 is coupled to the positive output terminal P+. When designing the layout and wiring of the battery management device, one end of the first electrostatic protection unit 11 is connected to the floating ground network, that is, connected to the negative electrode B- of the battery module. The floating ground network covers the pad at one end of the first electrostatic protection unit 11 when copper is laid, and the other end of the first electrostatic protection unit 11 is connected to the positive output terminal P+ network. The positive output terminal P+ network covers the pad at the other end of the first electrostatic protection unit 11 when copper is laid. During the layout and wiring design of the battery management device, the positive output terminal P+ and the negative electrode B- of the battery module are coupled to the same network through the first electrostatic protection unit 11. When static electricity exists on the positive output terminal P+, the electrostatic discharge circuit is: P+→first electrostatic protection unit 11→negative electrode B- of the battery module→ground. Because a large area of ​​copper is laid on the network where the negative electrode B- of the battery module is located, a large equivalent capacitance is formed between the network and the ground, providing a low-impedance electrostatic discharge path, thereby quickly dissipating the static electricity on the positive output terminal P+.

[0041] In some embodiments of the present application, the first electrostatic protection unit 11 includes a capacitor C. When static electricity exists on the positive output terminal P+, the static electricity is quickly coupled to the floating ground through the capacitor, thereby quickly dissipating the static electricity on the positive output terminal P+.

[0042] In some other embodiments of the present application, the first electrostatic protection unit 11 includes multiple capacitors C, and the multiple capacitors are connected in series. If the first electrostatic protection unit 11 includes only one capacitor, the failure of the capacitor will cause the static electricity to be unable to couple to the floating ground, and if one or more of the multiple capacitors connected in series fail, the static electricity on the positive output terminal P+ is coupled to the floating ground through the remaining capacitors, thereby improving the reliability of the electrostatic protection unit.

[0043] In some embodiments of the present application, one end of the second electrostatic protection unit 12 is coupled to the negative electrode B- of the battery module, and the other end of the second electrostatic protection unit 12 is coupled to the negative output terminal P-. When designing the layout and wiring of the battery management device, one end of the second electrostatic protection unit 12 is connected to the floating ground network, that is, connected to the negative electrode B- of the battery module. The floating ground network covers the pad at one end of the second electrostatic protection unit 12 when copper is laid, and the other end of the second electrostatic protection unit 12 is connected to the negative output terminal P- network. The negative output terminal P- network covers the pad at the other end of the second electrostatic protection unit 12 when copper is laid. The negative output terminal P- and the negative electrode B- of the battery module are coupled to the same network through the second electrostatic protection unit 12. When static electricity exists on the negative output terminal P-, the electrostatic discharge circuit is: P-→second electrostatic protection unit 12→negative electrode B- of the battery module→ground, because a large area of ​​copper is laid on the network where the negative electrode B- of the battery module is located, providing a low-impedance electrostatic discharge path, thereby quickly discharging the static electricity on the negative output terminal P-.

[0044] In some embodiments of the present application, the second electrostatic protection unit 12 includes a capacitor C. When static electricity exists on the negative output terminal P-, the static electricity is quickly coupled to the floating ground through the capacitor, thereby quickly dissipating the static electricity on the negative output terminal P-.

[0045] In some other embodiments of the present application, the second electrostatic protection unit 12 includes multiple capacitors C, and the multiple capacitors are connected in series. If the second electrostatic protection unit 12 includes only one capacitor, the failure of the capacitor will cause the static electricity to be unable to couple to the floating ground, and if one or more of the multiple capacitors connected in series fail, the static electricity on the negative output terminal P- is coupled to the floating ground through the remaining capacitors, thereby improving the reliability of the electrostatic protection unit.

[0046] After the static electricity is coupled to the floating ground, it is then coupled to the ground through the floating ground to discharge the static electricity. Figure 2 When designing the layout and wiring of the battery management equipment, the large area of ​​copper covering of the floating ground network is used to make the floating ground network and the ground have a large equivalent capacitance, so as to achieve the purpose of rapid discharge of static electricity.

[0047] In some embodiments of the present application, the power harness corresponding to the positive output terminal P+ and the power harness corresponding to the negative output terminal P- also have equivalent capacitance to the earth, see Figure 2 , the power harness corresponding to the positive output terminal P+ is coupled with the earth to discharge static electricity, and the power wire corresponding to the negative output terminal P- is coupled with the earth to discharge static electricity.

[0048] In the above embodiment of the present application, by setting a capacitor between the positive output terminal P+ and the negative electrode B- of the battery module, and between the negative output terminal P- and the negative electrode B- of the battery module, when static electricity exists on the positive output terminal P+, the static electricity is quickly coupled to the floating ground by the capacitor, and when static electricity exists on the negative output terminal P-, the static electricity is quickly coupled to the floating ground by the capacitor. Compared with the solution of using ESD or TVS in the related art to achieve electrostatic protection, the cost of electrostatic protection is effectively reduced. And the electrostatic protection solution of electrostatic coupling through capacitors is adopted to reduce the board layer design, and further reduce the cost and volume of PCB. In addition, the electrostatic protection solution in this embodiment has the characteristics of low cost and small volume, cleverly associates two independent networks, achieves the purpose of rapid discharge of static electricity to the floating ground, and simply and effectively realizes electrostatic protection, and has the characteristics of strong practicality in the actual application of the circuit. In summary, the electrostatic protection circuit provided in this embodiment is simple in design, low in cost, small in actual product space occupied by the circuit structure, and has good electrostatic protection capability.

[0049] See also Figure 3a , Figure 3b and Figure 3c On the basis of the above embodiment, the electrostatic protection circuit 1 further includes: a third electrostatic protection unit 13 and a fourth electrostatic protection unit 14 .

[0050] One end of the third electrostatic protection unit 13 is coupled to the positive electrode B+ of the battery module, and the other end of the third electrostatic protection unit 13 is coupled to the positive output terminal P+. When designing the layout and wiring of the battery management device, one end of the third electrostatic protection unit 13 is connected to the B+ network, and the B+ network covers the pad at one end of the third electrostatic protection unit 13 when copper is laid, and the other end of the third electrostatic protection unit 13 is connected to the P+ network, and the P+ network covers the pad at the other end of the third electrostatic protection unit 13 when copper is laid.

[0051] In some embodiments of the present application, the third electrostatic protection unit 13 includes a capacitor C. When static electricity exists on the positive output terminal P+, the static electricity is quickly coupled to the positive electrode B+ of the battery module through the capacitor.

[0052] In some other embodiments of the present application, the third electrostatic protection unit 13 includes multiple capacitors C, and the multiple capacitors are connected in series. If the third electrostatic protection unit 13 includes only one capacitor, the failure of the capacitor will cause the static electricity to be unable to couple to the positive electrode B+ of the battery module, and if one or more of the multiple capacitors connected in series fail, the static electricity on the positive output terminal P+ is coupled to the positive electrode B+ of the battery module through the remaining capacitors, thereby improving the reliability of the electrostatic protection unit.

[0053] One end of the fourth electrostatic protection unit 14 is coupled to the negative electrode B- of the battery module, and the other end of the fourth electrostatic protection unit 14 is coupled to the positive electrode B+ of the battery module. When designing the layout and wiring of the battery management device, one end of the fourth electrostatic protection unit 14 is connected to the floating ground network, that is, connected to the negative electrode B- of the battery module. The floating ground network covers the pad at one end of the fourth electrostatic protection unit 14 when copper is laid, and the other end of the fourth electrostatic protection unit 14 is connected to the B+ network. The B+ network covers the pad at the other end of the fourth electrostatic protection unit 14 when copper is laid.

[0054] In some embodiments of the present application, the fourth electrostatic protection unit 14 includes a capacitor C. When the third electrostatic protection unit 13 couples static electricity from the positive output terminal P+ to the positive electrode B+ of the battery module, the fourth electrostatic protection unit 14 quickly couples static electricity to the floating ground through the capacitor, thereby quickly discharging the static electricity on the positive output terminal P+.

[0055] In some other embodiments of the present application, the fourth electrostatic protection unit 14 includes multiple capacitors C, which are connected in series. If the fourth electrostatic protection unit 14 includes only one capacitor, the failure of the capacitor will cause the static electricity to be unable to couple to the floating ground, and if one or more of the multiple capacitors connected in series fail, the static electricity on the positive electrode B+ of the battery module is coupled to the floating ground through the remaining capacitors, thereby improving the reliability of the electrostatic protection unit.

[0056] On the basis of the first electrostatic protection unit 11, the third electrostatic protection unit 13 and the fourth electrostatic protection unit 14 provide another electrostatic coupling path: when static electricity exists on the positive output terminal P+, the static electricity is coupled to the floating ground, that is, the negative pole B- of the battery module, through the third electrostatic protection unit 13 and the fourth electrostatic protection unit 14, and finally the static electricity is discharged through the coupling of the floating ground and the earth. The electrostatic discharge path on the positive output terminal P+: positive output terminal P+→third electrostatic protection unit 13→fourth electrostatic protection unit 14→negative pole B- of the battery module→earth. Multiple electrostatic coupling paths provide more paths for static electricity discharge, discharge static electricity more quickly, and ensure the anti-static function of the battery management equipment. In addition, when one or several of the electrostatic coupling paths fail, static electricity is discharged through the remaining electrostatic coupling paths, which improves the reliability of the anti-static function.

[0057] Understandably, Figure 3a The circuit structure shown in Figure 1a Based on the circuit structure shown in the figure, Figure 3b The circuit structure shown in Figure 1b Based on the circuit structure shown in the figure, Figure 3c The circuit structure shown in Figure 1c The schematic is based on the circuit structure shown in .

[0058] See also Figure 4 , Figure 4 This is a seventh structural schematic diagram of the electrostatic protection circuit 1 provided in the embodiment of the present application. Based on the previous embodiments of the present application, the electrostatic protection circuit 1 further includes: a fifth electrostatic protection unit 15.

[0059] One end of the fifth electrostatic protection unit 15 is coupled to the positive output terminal P+, and the other end of the fifth electrostatic protection unit 15 is coupled to the negative output terminal P-. During the layout and wiring design of the battery management device, one end of the fifth electrostatic protection unit 15 is connected to the P+ network, and the P+ network covers the pad at one end of the fifth electrostatic protection unit 15 when copper is laid, and the other end of the fifth electrostatic protection unit 15 is connected to the P- network, and the P- network covers the pad at the other end of the fifth electrostatic protection unit 15 when copper is laid.

[0060] In some embodiments of the present application, the fifth electrostatic protection unit 15 includes a capacitor C. When static electricity exists on the positive output terminal P+, the static electricity is quickly coupled to the negative output terminal P- through the capacitor.

[0061] In some other embodiments of the present application, the fifth electrostatic protection unit 15 includes multiple capacitors C, which are connected in series. If the fifth electrostatic protection unit 15 includes only one capacitor, the failure of the capacitor will cause the static electricity to be unable to couple to the negative output terminal P-, and if one or more of the multiple capacitors connected in series fail, the static electricity on the positive output terminal P+ is coupled to the negative output terminal P- through the remaining capacitors, thereby improving the reliability of the electrostatic protection unit.

[0062] After the static electricity on the positive output terminal P+ is coupled to the negative output terminal P-, it is then coupled to the floating ground, that is, the negative electrode B- of the battery module, through the second static electricity protection unit 12, and the static electricity is discharged through the floating ground coupling with the earth.

[0063] On the basis of the above circuit structure, the fifth electrostatic protection unit 15 provides another electrostatic coupling path: when static electricity exists on the positive output terminal P+, the static electricity is coupled to the floating ground, that is, the negative pole B- of the battery module, through the fifth electrostatic protection unit 15 and the second electrostatic protection unit 12, and then the static electricity is discharged through the floating ground and coupling with the earth. The static electricity discharge path on the positive output terminal P+: positive output terminal P+→fifth electrostatic protection unit 15→second electrostatic protection unit 12→negative pole B- of the battery module→earth. Multiple electrostatic coupling paths provide more paths for static electricity discharge, discharge static electricity more quickly, and ensure the anti-static function of the battery management equipment. In addition, when one or several of the electrostatic coupling paths fail, the static electricity is discharged through the remaining electrostatic coupling paths, which improves the reliability of the anti-static function.

[0064] Understandably, Figure 4 The circuit structure shown in Figure 3cBased on the circuit structure shown in the figure, Figure 5 The circuit structure shown in Figure 1c The schematic is based on the circuit structure shown in .

[0065] It is understandable that the present application will not elaborate on the fifth electrostatic protection unit 15 based on other circuit structures.

[0066] As a specific embodiment of the present application, each electrostatic protection unit includes multiple capacitors, see Figure 6 , the first electrostatic protection unit 11 includes a first capacitor C1 and a second capacitor C2, the second electrostatic protection unit 12 includes a third capacitor C3 and a fourth capacitor C4, the third electrostatic protection unit 13 includes a fifth capacitor C5 and a sixth capacitor C6, the fourth electrostatic protection unit 14 includes a seventh capacitor C7 and an eighth capacitor C8, and the fifth electrostatic protection unit 15 includes a ninth capacitor C9 and a tenth capacitor C10. In this embodiment, the electrostatic protection circuit provides four electrostatic discharge paths, including: three electrostatic discharge paths of the positive output terminal P+ and one electrostatic discharge path of the negative output terminal P-, and the electrostatic discharge paths are respectively: positive output terminal P+→first electrostatic protection unit 11→battery module negative electrode B-, positive output terminal P+→third electrostatic protection unit 13→fourth electrostatic protection unit 14→battery module negative electrode B-, positive output terminal P+→fifth electrostatic protection unit 15→second electrostatic protection unit 12→battery module negative electrode B-, negative output terminal P-→second electrostatic protection unit 12→battery module negative electrode B-.

[0067] Generally speaking, the larger the capacitance of a capacitor, the stronger its ability to store charge. Therefore, when discharging static electricity, a capacitor with a large capacitance can better absorb and neutralize static charges, effectively reducing the impact of static electricity on circuits or equipment. Of course, the larger the capacitance, the better. By selecting a capacitor with a suitable capacitance, such as a capacitor with a capacitance of 47nf and 100nf, the electrostatic protection performance can be ensured to be optimal.

[0068] In some embodiments of the present application, the capacitance of each capacitor in the same electrostatic protection unit is the same. For example, the first capacitor C1 and the second capacitor C2 in the first electrostatic protection unit 11 have the same capacitance, both of which are 100 nF.

[0069] In some other embodiments of the present application, the capacitances of the capacitors in the same electrostatic protection unit are different. For example, the capacitance of the first capacitor C1 in the first electrostatic protection unit 11 is 100 nf, and the capacitance of the second capacitor C2 is 47 nf.

[0070] In some embodiments of the present application, the capacitance values ​​of capacitors in different electrostatic protection units are different. For example, the capacitance values ​​of the first capacitor C1 and the second capacitor C2 in the first electrostatic protection unit 11 are 100 nf, and the capacitance values ​​of the third capacitor C3 and the fourth capacitor in the second electrostatic protection unit are 47 nf.

[0071] In some other embodiments of the present application, the capacitance values ​​of capacitors in different electrostatic protection units are the same. For example, the capacitance values ​​of the first capacitor C1 and the second capacitor C2 in the first electrostatic protection unit 11 are 100 nf, and the capacitance values ​​of the third capacitor C3 and the fourth capacitor in the second electrostatic protection unit are 100 nf.

[0072] Specifically, when static electricity exists on the positive output terminal P+, the static electricity is coupled to the negative electrode B- of the battery module through the first capacitor C1 and the second capacitor C2 in the first electrostatic protection circuit 11, and the static electricity is coupled to the negative electrode B- of the battery module through the fifth capacitor C5 and the sixth capacitor C6 in the third electrostatic protection circuit 13, and then through the seventh capacitor 17 and the eighth capacitor 18 in the fourth electrostatic protection unit 14, and the static electricity is coupled to the negative electrode B- of the battery module through the ninth capacitor C9 and the tenth capacitor C10 in the fifth electrostatic protection circuit 15, and then through the third capacitor C3 and the fourth capacitor C4 in the second electrostatic protection unit 12. When static electricity exists on the negative output terminal P-, the static electricity is coupled to the negative electrode B- of the battery module through the third capacitor C3 and the fourth capacitor C4 in the second electrostatic protection unit 12. Finally, when static electricity exists on the positive output terminal P+, it is discharged through the positive output terminal P+, the negative output terminal P-, the negative pole B- of the battery module and the coupling with the earth; when static electricity exists on the negative output terminal P-, it is discharged through the negative output terminal P-, the negative pole B- of the battery module and the coupling with the earth.

[0073] Multiple electrostatic coupling paths provide more paths for static discharge, discharge static electricity more quickly, and ensure the anti-static function of the battery management device. In addition, when one or several electrostatic coupling paths fail, static electricity is discharged through the remaining electrostatic coupling paths, improving the reliability of the anti-static function.

[0074] In some embodiments of the present application, Figure 4 Based on the circuit structure shown, an empty pad or a tip discharge pad is used to replace the capacitor to achieve the electrostatic protection function. When designing the PCB, a tip discharge part is set on the pad. The tip discharge part is a pair of triangles with sharp angles pointing to each other. It is made of copper foil during the PCB wiring process. When encountering electrostatic discharge, the tip structures of the two pads will discharge each other, thereby reducing damage to devices and circuits.

[0075] The present application also provides a battery management device 2, see Figure 7The battery management device 2 includes the electrostatic protection circuit 1 described in any one of the above embodiments.

[0076] For an example, see Figure 8 , Figure 8 A schematic diagram of the structure of the battery management device 2 (based on Figure 6 The electrostatic protection circuit shown in the figure), the battery management device 2 also includes a fuse F1, a control module 21, a first switch Q1, a second switch Q2, and a first resistor R1.

[0077] The function of the fuse F1 is: when the current in the circuit abnormally rises to a certain limit, the fuse F1 will melt itself to cut off the current and protect the safe operation of the circuit. The first resistor R1 is a sampling resistor, which plays the role of collecting current.

[0078] The battery management device 2 is used to monitor the voltage of each battery cell in the battery module, the current of the charge and discharge circuit, and the battery cell temperature, etc. (the battery module includes multiple battery cells), and controls the on and off of the first switch Q1 and the second switch Q2 through its own control module 21 to control the charge and discharge process of the battery module. When the battery pack is in a normal working state (including normal charging and normal discharging), the control module 21 controls the first switch Q1 and the second switch Q2 to be turned on. When the battery pack is in an abnormal state, the control module 21 controls the first switch Q1 and the second switch Q2 to be turned off to protect the safety of the battery cell. It can be understood that the abnormal state of the battery pack includes: overcurrent, overvoltage, overtemperature, over-discharge, etc.

[0079] The present application also provides a battery pack 3, which is used to store and provide electrical energy. Fig. 9 , including a battery module 31, a connector 32 (first connector) and the battery management device 2 described in the above embodiment, the battery management device 2 is electrically connected to the battery module 31 and the connector 32 respectively. As mentioned above, the connector 32 includes a positive output terminal P+ and a negative output terminal P-.

[0080] The present application embodiment also provides an electric device 4, see Fig.10 , including a load 41 and the battery pack 3 described in the above embodiment.

[0081] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0082] To enable those skilled in the art to realize or use the disclosure of the present application, description herein and above embodiments are provided. For those skilled in the art, various modifications to the disclosure of the present application will be apparent, and without departing from the scope of the disclosure of the present application, the general principles defined herein are also applied to other variations. Therefore, the disclosure of the present application is not limited to the examples and designs described herein, but is given the widest scope consistent with the principles disclosed herein and novel features.

Claims

1. An electrostatic protection circuit, characterized in that: include: A first electrostatic protection unit is configured to be electrically connected between the positive output terminal and the negative electrode of the battery module, and the first electrostatic protection unit includes at least one capacitor; and / or, The second electrostatic protection unit is configured to be electrically connected between the negative electrode output terminal and the negative electrode of the battery module, and the second electrostatic protection unit includes at least one capacitor.

2. The electrostatic protection circuit according to claim 1, characterized in that: The first electrostatic protection unit includes a plurality of capacitors, each of which is connected in series; and / or, The second electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series.

3. The electrostatic protection circuit according to claim 1 or 2, characterized in that: include: a third electrostatic protection unit, wherein a first end of the third electrostatic protection unit is electrically connected to a first end of the first electrostatic protection unit, the first end of the third electrostatic protection unit is further configured to be electrically connected to the positive output terminal, and a second end of the third electrostatic protection unit is configured to be electrically connected to the positive electrode of the battery module; a fourth electrostatic protection unit, wherein a first end of the fourth electrostatic protection unit is electrically connected to a second end of the third electrostatic protection unit, the first end of the fourth electrostatic protection unit is further configured to be electrically connected to a positive electrode of the battery module, and the second end of the fourth electrostatic protection unit is configured to be electrically connected to a negative electrode of the battery module; The third electrostatic protection unit includes at least one capacitor, and the fourth electrostatic protection unit includes at least one capacitor.

4. The electrostatic protection circuit according to claim 3, characterized in that: The third electrostatic protection unit includes a plurality of capacitors, each of which is connected in series; The fourth electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series.

5. The electrostatic protection circuit according to any one of claims 1 to 4, characterized in that: include: a fifth electrostatic protection unit, wherein a first end of the fifth electrostatic protection unit is electrically connected to a first end of the first electrostatic protection unit, the first end of the fifth electrostatic protection unit is further configured to be electrically connected to the positive output terminal, and a second end of the fifth electrostatic protection unit is configured to be electrically connected to the negative output terminal; The fifth electrostatic protection unit includes at least one capacitor.

6. The electrostatic protection circuit according to claim 5, characterized in that: The electrostatic protection circuit includes the first electrostatic protection unit and the second electrostatic protection unit, the second end of the fifth electrostatic protection unit is electrically connected to the first end of the second electrostatic protection unit, and the second end of the second electrostatic protection unit is configured to be electrically connected to the negative pole of the battery module.

7. The electrostatic protection circuit according to claim 5 or 6, characterized in that: The fifth electrostatic protection unit includes a plurality of capacitors, and each of the plurality of capacitors is connected in series.

8. A battery management device, characterized in that: The invention comprises the electrostatic protection circuit as claimed in any one of claims 1 to 7.

9. A battery pack, characterized in that: It comprises a battery module, a connector and a battery management device as claimed in claim 8, wherein the battery module comprises a plurality of battery cells; The connector includes a positive output terminal and a negative output terminal; The battery management device is electrically connected to the battery module and the connector respectively.

10. The battery pack according to claim 9, characterized in that: The negative electrode of the battery module, the positive output terminal and the negative output terminal are respectively coupled to the ground.

11. An electrical device, characterized in that: Comprising a load and a battery pack as claimed in claim 9 or 10.

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