Battery module, power battery pack and electric equipment

Abstract

The embodiment of the utility model provides a battery module, a power battery pack and electric equipment. The battery module comprises a plurality of single batteries, and each single battery is provided with an output electrode; the busbars are configured to be distributed in the first direction, and the busbars are connected with the output electrodes of the two adjacent single batteries; and one end of the fuse link is connected with the shell of the battery monomer, and the other end is connected with the busbar or the other end is connected between the busbar and the output electrode. A plurality of battery monomers are connected through a busbar, and a fuse link is respectively connected with the busbar and a shell of the battery monomers, so that the shell and an output electrode are connected to a voltage sampling circuit, the voltage between the output electrode of the battery monomers and the shell in the whole pack is detected in real time, and when an abnormal short circuit phenomenon occurs inside or outside the battery monomers, the fuse link is fused, and the battery monomers are charged. When the power battery pack is used, the voltage between the output electrode and the shell changes, and the safety and reliability of the power battery pack in use can be judged in an auxiliary manner by monitoring the dynamic change condition of the voltage.

Description

Technical Field

[0001] The present application relates to the technical field of power battery packs, and more specifically, to a battery module, a power battery pack and electrical equipment. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automotive industry. Electric vehicles have become an important part of the sustainable development of the automotive industry due to their advantages in energy conservation and environmental protection. For electric vehicles, power battery pack technology is an important factor in their development.

[0003] In the development of power battery pack technology, in addition to improving the energy density of power battery packs, the safety of power battery packs is also an issue that cannot be ignored. Therefore, how to improve the safety performance of power battery packs is a technical problem that needs to be solved urgently in power battery pack technology. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a battery module, a power battery pack and an electrical device, which can assist in judging the safety and reliability of the power battery pack during use by monitoring the dynamic changes in voltage.

[0005] In a first aspect, an embodiment of the present application provides a battery module, comprising: a plurality of battery cells, wherein the plurality of battery cells are configured to be distributed along a first direction, and the battery cells are configured with output poles; a bus, which is configured to be distributed along the first direction, and the bus connects the output poles of two adjacent battery cells; a fuse, one end of which is connected to the housing of the battery cell, and the other end is connected to the bus, or the other end is connected between the bus and the output pole.

[0006] In the above implementation process, several battery cells are connected through a bus, and the fuse is respectively connected to the bus and the shell of the battery cell, so that the shell and the output pole are connected to the voltage sampling circuit, and the voltage between the output pole and the shell of the battery cell in the whole pack is detected in real time. When an abnormal short circuit occurs inside or outside the battery cell, the fuse blows, and the voltage between the output pole and the shell will change. The dynamic change of the voltage can be monitored to assist in judging the safety and reliability of the power battery pack during use.

[0007] In some embodiments, the output pole includes a positive pole.

[0008] In some embodiments, the rated current of the fuse is less than 10A.

[0009] In some embodiments, the resistance of the fuse is less than 1000Ω.

[0010] In some embodiments, the rated voltage of the fuse is greater than an upper limit voltage after a plurality of the battery cells are connected.

[0011] In some embodiments, the fuse includes a fuse, a first connector and a second connector, the first connector and the second connector are both connected to the fuse, the first connector is connected to the housing, and the second connector is connected to the bus.

[0012] In the above implementation process, the fuse is respectively connected to the first connector and the second connector to realize external electrical connection between the output pole and the shell, which is beneficial to increase the potential of the shell and reduce the risk of electrochemical corrosion of the shell. When the insulation of the entire package fails, the fuse blows, so that the insulation between the output pole of the battery cell and the shell is restored, thereby realizing the demand for safety protection of the insulation of the entire package.

[0013] In some embodiments, a plurality of the battery cells are connected in series via the bus bar.

[0014] In a second aspect, the present application also provides a power battery pack, comprising a battery module as described in any one of the above items.

[0015] Since the second embodiment of the present application provides a power battery pack, which includes the battery module described in the technical solution of the first aspect, it has all the technical effects of the above embodiments and will not be repeated here.

[0016] In a third aspect, the present application also provides an electrical device, comprising the power battery pack as described above.

[0017] Since the third embodiment of the present application provides an electrical device, and since it includes the power battery pack described in the second technical solution, it has all the technical effects of the above embodiments, which will not be repeated here.

[0018] Other features and advantages of the present disclosure will be set forth in the following description, or some features and advantages may be inferred or unambiguously determined from the description, or may be learned by implementing the above-mentioned technology of the present disclosure.

[0019] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1A schematic diagram of the structure of a battery module provided in an embodiment of the present application;

[0022] Figure 2 A front view of a battery module provided in an embodiment of the present application.

[0023] Reference numerals

[0024] 100, battery cell; 101, housing; 200, bus bar; 300, fuse. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0026] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0027] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0028] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or a point connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0030] Example

[0031] During the design process, the inventors found that the square aluminum shell is the most commonly used structural form for lithium-ion power battery packs, and has stable and reliable structural characteristics. However, since the spacing between the octahedrons of the aluminum metal lattice is similar to that of lithium metal, it will undergo an electrochemical reaction with lithium ions under the lithium embedding potential of aluminum metal to generate Al-Li alloy, causing the aluminum shell to perforate and leak. Electrochemical corrosion of the aluminum shell is one of the main reasons for the failure of lithium-ion power battery packs, and it is also a safety hazard that must be eliminated.

[0032] By setting an electronic path between the cathode pole of the lithium-ion power battery pack and the power battery pack shell (the shell is charged), the condition threshold for the aluminum shell corrosion reaction can be increased, and the shell corrosion caused by the micro-short circuit between the negative electrode and the shell caused by the process can be effectively avoided. Moreover, the smaller the resistance between the cathode pole and the aluminum shell, the higher the theoretical corrosion condition threshold, that is, the smaller the resistance between the negative electrode and the shell, the corrosion will occur. However, the disadvantage of this solution is that since the shell and the positive electrode are connected through resistance, once the battery cell shells connected in series in the power battery pack group are in non-insulated contact, it will cause an external short circuit of the power battery pack group. The higher the voltage of the power battery pack group, the higher the short circuit risk. In terms of the insulation risk of the entire package, maintaining electronic insulation between the cathode pole and the shell (the shell is not charged) will greatly reduce the risk of short circuit and high-voltage arcing, but it will lead to an increase in the risk of corrosion of the battery cell shell.

[0033] There are two main existing technical solutions: one is to reduce the risk of shell corrosion by adopting a live shell design, and the other is to reduce the risk of insulation failure of the entire package by adopting a non-live shell design. Both solutions fail to take into account the dual requirements of reducing shell corrosion and preventing insulation failure of the entire package.

[0034] In view of this, if Figure 1-Figure 2 As shown, in the first aspect, an embodiment of the present application provides a battery module, comprising: a plurality of battery cells 100, wherein the plurality of battery cells 100 are configured to be distributed along a first direction, and the battery cells 100 are configured with an output pole; a bus bar 200, which is configured to be distributed along the first direction, and the bus bar 200 connects the output poles of two adjacent battery cells 100; a fuse 300, one end of which is connected to the housing 101 of the battery cell 100, and the other end is connected to the bus bar 200, or the other end is connected between the bus bar 200 and the output pole.

[0035] Exemplarily, the battery module is configured with several, and the several battery modules can be connected in series, in parallel or mixed to form a power battery pack. The total voltage of the power battery pack is greater than 200V. The output pole (such as the cathode pole) of the battery cell 100 and its own shell 101 are designed with electronic insulation. When the battery cell 100 is not filled with liquid, the resistance value between the cathode pole and the shell 101 is greater than 200MΩ. Through the whole pack level circuit design, the fuse 300 is arranged between the output pole of the battery cell 100 and the shell 101 in the battery pack. The fuse 300 connects the output pole of the battery cell 100 and its own shell 101 to improve the safety of the battery cell 100 when in use.

[0036] In order to prevent the fuse 300 from arcing as a whole and causing damage to the housing 101 of the battery cell 100 when the insulation of the entire package fails, the fuse 300 includes but is not limited to a closed fuse 300.

[0037] In the present application, the battery cell 100 includes an electrode assembly and an electrolyte, and the electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell 100 mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer, and the positive electrode collector not coated with the positive electrode active material layer serves as a positive electrode ear. Taking a lithium-ion power battery pack as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon or silicon, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. The material of the isolation film may be PP (polypropylene) or PE (polyethylene), etc.

[0038] Among them, the battery cell 100 may include a lithium-ion secondary power battery pack, a lithium-ion primary power battery pack, a lithium-sulfur power battery pack, a sodium-lithium-ion power battery pack, a sodium-ion power battery pack or a magnesium-ion power battery pack, etc. This application takes a lithium-ion power battery pack as an example.

[0039] In the above implementation process, several battery cells 100 are connected through the bus 200, and the fuse 300 is respectively connected to the bus 200 and the shell 101 of the battery cell 100, so that the shell 101 and the output pole are connected to the voltage sampling circuit, and the voltage between the output pole and the shell 101 of the battery cell 100 in the whole pack is detected in real time. When an abnormal short circuit occurs inside or outside the battery cell 100, the fuse 300 melts, and the voltage between the output pole and the shell 101 will change. The dynamic change of the voltage can be monitored to assist in judging the safety and reliability of the power battery pack during use.

[0040] In some embodiments, the output pole includes a positive pole.

[0041] In some embodiments, the rated current of the fuse 300 is less than 10 A. Preferably, the rated current of the fuse 300 is less than 1A.

[0042] In some embodiments, the resistance value of the fuse 300 is less than 1000Ω. Preferably, the rated resistance value of the fuse 300 is less than 50Ω.

[0043] In some embodiments, the rated voltage of the fuse 300 is greater than the upper limit voltage of a plurality of the battery cells 100 connected together, that is, the rated voltage of the fuse 300 is greater than the upper limit voltage of the entire battery pack.

[0044] In some embodiments, the fuse 300 includes a fuse, a first connector and a second connector, the first connector and the second connector are both connected to the fuse, the first connector is connected to the housing 101 , and the second connector is connected to the bus 200 .

[0045] In the above implementation process, the fuse is respectively connected to the first connector and the second connector to realize external electrical connection between the output pole and the shell 101, which is beneficial to increase the potential of the shell 101 and reduce the risk of electrochemical corrosion of the shell 101. When the insulation of the entire package fails, the fuse blows, so that the insulation between the output pole of the battery cell 100 and the shell 101 is restored, thereby realizing the requirement of insulation safety protection of the entire package.

[0046] In some embodiments, a plurality of the battery cells 100 are connected in series via the bus bar 200 .

[0047] In a second aspect, the present application also provides a power battery pack, comprising a battery module as described in any one of the above items.

[0048] Since the second embodiment of the present application provides a power battery pack, which includes the battery module described in the technical solution of the first aspect, it has all the technical effects of the above embodiments and will not be repeated here.

[0049] In a third aspect, the present application also provides an electrical device, comprising the power battery pack as described above.

[0050] The battery cell 100 disclosed in the embodiment of the present application can be used in, but not limited to, electrical equipment such as vehicles, ships or aircraft. The battery cell 100 disclosed in the present application can be used to form a power supply system of the electrical equipment.

[0051] The embodiment of the present application provides an electric device using a power battery pack as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0052] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0053] The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle. A power battery pack is arranged inside the vehicle, and the power battery pack may be arranged at the bottom, head or tail of the vehicle. The power battery pack may be used to power the vehicle. For example, the power battery pack may be used as an operating power source for the vehicle and for the circuit system of the vehicle, such as for the starting, navigation and working power requirements of the vehicle during operation.

[0054] The vehicle may also include a controller and a motor, where the controller is used to control the power battery pack to supply power to the motor, for example, to meet the vehicle's operating power requirements during starting, navigation, and driving.

[0055] In some embodiments of the present application, the power battery pack can not only serve as the operating power source of the vehicle, but also serve as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0056] Since the third embodiment of the present application provides an electrical device, and since it includes the power battery pack described in the second technical solution, it has all the technical effects of the above embodiments, which will not be repeated here.

[0057] In all the embodiments of the present application, "big" and "small" are relative, "more" and "less" are relative, and "up" and "down" are relative. The expressions of such relative terms are not elaborated in the embodiments of the present application.

[0058] It should be understood that the "in this embodiment", "in the embodiment of the present application" or "as an optional implementation" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in this embodiment", "in the embodiment of the present application" or "as an optional implementation" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. Those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required for the present application.

[0059] In the various embodiments of the present application, it should be understood that the size of the serial numbers of the above-mentioned processes does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0060] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A battery module, characterized in that: include: A plurality of battery cells, wherein the plurality of battery cells are arranged to be distributed along a first direction, and the battery cells are provided with output poles; A bus bar, which is arranged to be distributed along the first direction, and the bus bar connects the output poles of two adjacent battery cells; A fuse has one end connected to the housing of the battery cell and the other end connected to the bus bar, or the other end connected between the bus bar and the output pole.

2. The battery module according to claim 1, characterized in that: The output pole includes a positive pole.

3. The battery module according to claim 1, characterized in that: The rated current of the fuse is less than 10A.

4. The battery module according to claim 1, characterized in that: The resistance value of the fuse is less than 1000Ω.

5. The battery module according to claim 1, characterized in that: The rated voltage of the fuse is greater than the upper limit voltage after a plurality of the battery cells are connected.

6. The battery module according to claim 1, characterized in that: The fuse includes a fuse, a first connecting body and a second connecting body. The first connecting body and the second connecting body are both connected to the fuse, and the first connecting body is connected to the housing, and the second connecting body is connected to the busbar.

7. The battery module according to claim 1, characterized in that: A plurality of the battery cells are connected in series via the bus bar.

8. A power battery pack, characterized in that: Comprising a battery module as described in any one of claims 1 to 7.

9. An electrical device, characterized in that: Comprising the power battery pack as claimed in claim 8.

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