Battery pack for vehicle and vehicle

Abstract

The invention relates to a battery pack and a vehicle including the same. The battery pack includes: a case; the plurality of battery modules are arranged in the box body; the battery management system is arranged in the box body and comprises a main control unit and a plurality of slave control units which are arranged in parallel, one end of each slave control unit is connected to the corresponding battery module in the plurality of battery modules, and the other end of each slave control unit is connected to the main control unit; wherein the circuit board of the master control unit is provided with a thick-film resistor, and / or the circuit board of at least one of the slave control units is provided with a thick-film resistor. The battery pack provided by the invention has a plurality of advantages, particularly, the thick-film resistor is arranged in the battery management system, so that the battery pack has relatively good corrosion resistance in a complex battery environment, and the stability and the reliability in a long-term operation process are improved.

Description

Technical Field

[0001] The present invention generally relates to the field of vehicle components, and more particularly, the present invention relates to a battery pack for a vehicle, and a vehicle including the battery pack. Background Art

[0002] Compared with traditional fuel vehicles, the voltage of electric vehicles is mainly used to drive the motor to work and store a large amount of energy, so high voltage is required to meet the requirements of high-efficiency drive.

[0003] The battery management system BMS (Battery Management System) is one of the core components of electric vehicles, and is used to manage and maintain the health status and safety performance of battery modules.

[0004] In the BMS system, thin film resistors are commonly used in voltage sampling and current detection of battery modules and other links. When the thin film resistor material is eroded by chemical substances in the battery electrolyte or is in a high humidity environment for a long time, a corrosion reaction will occur on its surface. Especially under the conditions of high voltage and large current in electric vehicles, the resistance value is likely to change or even gradually fail, and serious electrical corrosion may cause the circuit to break, making the BMS system unable to accurately obtain battery state information, and ultimately threatening the safety and service life of the vehicle. Summary of the Invention

[0005] The object of the present invention is to provide a battery pack for a vehicle to overcome the above-mentioned defects of the prior art. That is to say, the battery pack according to the present invention can reduce the problem of resistance electrical corrosion in the battery management system and improve the safety performance of the vehicle.

[0006] To this end, a first aspect of the present invention provides a battery pack for a vehicle, including: a box body; a plurality of battery modules, the plurality of battery modules being disposed in the box body; and a battery management system, the battery management system being disposed in the box body and including a main control unit and a plurality of slave control units connected in parallel, one end of each of the plurality of slave control units being connected to a corresponding battery module among the plurality of battery modules, and the other end being connected to the main control unit; wherein, a thick film resistor is disposed on the circuit board of the main control unit, and / or, a thick film resistor is disposed on the circuit board of at least one of the plurality of slave control units.

[0007] According to an optional embodiment of the present invention, each of the plurality of slave control units is connected to the corresponding battery module through a copper bar, and the thick film resistor is provided when the voltage of the copper bar is greater than 60V.

[0008] According to an optional embodiment of the present invention, the maximum overload voltage of the thick film resistor is set to 400V.

[0009] According to an alternative embodiment of the present invention, the tolerance of the thick film resistor is set to ±0.1%.

[0010] According to an alternative embodiment of the present invention, the circuit board is coated with an IPX7 - level nano - material waterproof coating that at least covers the thick film resistor.

[0011] According to an alternative embodiment of the present invention, the thickness of the nano - material waterproof coating is between 50 microns and 60 microns.

[0012] According to an alternative embodiment of the present invention, the housing covering the circuit board of the main control unit and / or the housing covering the circuit board of at least one of the plurality of slave control units is set to an IPX7 - level sealed structure.

[0013] A second aspect of the present invention provides a vehicle, which includes the battery pack according to the first aspect of the present invention.

[0014] Compared with the prior art, the battery pack according to the present invention has multiple advantages, especially: by setting thick film resistors in the battery management system, it has better corrosion resistance in a complex battery environment, improving stability and reliability during long - term operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features and advantages of the present invention will be better understood through the following preferred embodiments described in detail in conjunction with the drawings. In the drawings, the same reference numerals represent the same or similar components.

[0016] Figure 1 is a schematic diagram of a vehicle with a preferred embodiment of the battery pack according to the present invention;

[0017] Figure 2 is Figure 1 a partial perspective view of the battery pack of the vehicle in

[0018] Figure 3 is Figure 2 the architecture diagram of the battery management system of the battery pack in DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The implementation and use of specific embodiments are discussed in detail below. However, it should be understood that the specific embodiments discussed are only exemplary of specific ways of implementing and using the present invention, and do not limit the scope of the present invention.

[0020] In this specification, unless otherwise clearly specified or limited, terms such as "connection" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, or the communication between two components or the interaction relationship between two components. For those skilled in the art, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0021] As Figure 1 and Figure 2 shown, the vehicle V is, for example, an electric vehicle or a hybrid vehicle, and a power battery pack A is provided at the bottom thereof. The battery pack A includes a box body 41 (a part of the box body 41 is shown in the figure) and a plurality of battery modules 1 and a battery management system 3 provided in the box body 41. Among them, the battery management system 3 includes a main control unit 33 and a plurality of slave control units 31, 32 arranged in parallel.

[0022] One end of each of the plurality of slave control units 31, 32 is connected to the corresponding battery module 1 among the plurality of battery modules 1, and the other end is connected to the main control unit 33. More specifically, as Figure 3 shown, the plurality of slave control units 31, 32 include a first slave control unit 31 and a second slave control unit 32, and the plurality of battery modules 1 include a first battery module 11 and a second battery module 12. Among them, the first battery module 11 is provided with a plurality of flexible busbars 111, the first slave control unit 31 and the main control unit 33 are respectively provided with a plurality of first connectors 311 and a plurality of second connectors 331. The flexible busbar 111 is first connected to the copper busbar 62 through the sampling line 61, and the copper busbar 62 is then connected to the first connector 311 at one end of the first slave control unit 31 through the sampling line 61. The first connector 311 at the other end of the first slave control unit 31 is finally connected to the second connector 331 through the communication line 63. The connection method of the second slave control unit 32 is the same as that of the first slave control unit 31 and will not be described in detail.

[0023] The first slave control unit 31 and the second slave control unit 32 respectively accurately monitor data such as voltage, current, and temperature of the first battery module 11 and the second battery module 12, and transmit this data to the main control unit 33. The main control unit 33 is arranged on a bracket 411 connected to the box body 41, and is mainly used for integrating and analyzing battery data, performing equalization control and safety management, etc., and performing internal and external information exchange through a CAN (Controller Area Network) bus or other communication protocols. This split-type battery management system 3 has flexible configuration, is easy to maintain and upgrade, and is safe and reliable.

[0024] According to an implementation variant, the battery management system can also be set to a centralized architecture, that is, the master control unit and the slave control units are integrated on one module. Compared with the split type, data acquisition, data processing, issuing control instructions, etc. of the centralized battery management system are all completed by one module. Therefore, this architecture has a simple structure, convenient communication, and low cost. However, since all functions need to be integrated on one circuit board, the sampling wire harness is long, which easily leads to inconsistent voltage drops on the wires during balancing, affecting the balancing effect. At the same time, due to the limited number of centralized acquisition channels, the applicability is poor, and it is only suitable for small battery packs.

[0025] According to the present invention, a thick film resistor is provided on the circuit board of the master control unit 33, and / or a thick film resistor is provided on the circuit board of at least one of the multiple slave control units 31, 32. For example, the sampling resistor on the circuit board of the master control unit 33 is set as a thick film resistor. It can be understood that other resistors on the circuit board, such as balancing resistors, filtering resistors, etc. can also be set as thick film resistors, and the present invention does not limit this.

[0026] Among them, "and / or" means that the master control unit 33 and the slave control units 31, 32 do not necessarily both have thick film resistors at the same time. According to one implementation manner, the master control unit 33 is provided with a thick film resistor, and the slave control units 31, 32 are not provided with thick film resistors. According to another implementation manner, the master control unit 33 is provided with a thick film resistor, and any one of the first slave control unit 31 or the second slave control unit 32 is provided with a thick film resistor. According to another implementation manner, the master control unit 33 is provided with a thick film resistor, and each of the first slave control unit 31 and the second slave control unit 32 is provided with a thick film resistor. It can be understood that in different circuit designs, the selection and configuration of thick film resistors are set according to actual functional requirements, and the present invention does not limit this.

[0027] Preferably, each of the multiple slave control units 31, 32 is connected to the corresponding battery module 1 through a copper busbar 62 as described above, and the thick film resistor is provided when the voltage of the copper busbar 62 is greater than 60V. At this time, setting the thick film resistor in the slave control unit can make full use of the high voltage tolerance, high power processing ability, and excellent thermal stability of the thick film resistor.

[0028] Preferably, the maximum overload voltage of the thick film resistor is set to 400V, that is, when there is an instantaneous high voltage impact or the voltage temporarily rises due to the failure of other components in the circuit, the thick film resistor can safely handle a voltage of up to 400V without being immediately damaged. Also preferably, the tolerance of the thick film resistor is set to ±0.1%. Among them, "tolerance" represents the allowable deviation range between the actual resistance value and the nominal resistance value. The smaller the tolerance, the higher the accuracy of the thick film resistor. High-precision thick film resistors are suitable for occasions where precise control of current, voltage, or signal strength is required.

[0029] The thick film resistor in the vehicle battery pack of the present invention has high withstand voltage ability and high precision grade, can provide stable resistance value and low temperature coefficient, and maintain high precision at the same time. It can work stably in harsh environments such as high temperature and high humidity. In addition, the thick film resistor is suitable for surface mount technology and can be conveniently assembled in batches with other electronic components through an automated production line, thereby improving the assembly efficiency of the battery management system 3 and reducing the manufacturing cost.

[0030] Preferably, the circuit board provided with the thick film resistor is coated with an IPX7-level nano-material waterproof coating that at least covers the thick film resistor. Among them, IPX7 indicates a waterproof level of 7, that is, under the specified test conditions, the product can be continuously immersed in water at a depth of 1 meter for 30 minutes without water ingress. Preferably, the thickness of the nano-material waterproof coating is between 50 microns and 60 microns. More preferably, the thickness of the nano-material waterproof coating is between 52 microns and 58 microns, for example, about 55 microns. Alternatively, a three-proof protective paint such as moisture-proof, salt spray-proof and mildew-proof with a thickness between 90 microns and 120 microns can also be coated on the circuit board of the thick film resistor.

[0031] This waterproof coating is usually applied to the surface of the circuit board and components by spraying, dipping or vacuum coating to form a transparent and closely adhering protective film to prevent moisture and other harmful substances from invading, thereby improving the reliability and service life of the battery management system 3.

[0032] In addition, the housing (the housing of the main control unit 33 and / or the housing of at least one of the multiple slave control units 31, 32) covering the circuit board provided with the thick film resistor can be set as an IPX7-level sealed structure. For example, by setting a sealing ring and a sealing strip at the joint surface of the two half-shells to ensure the close fit and effective sealing between the two half-shells.

[0033] It can be understood that at least the high-voltage line part in other high-voltage components (such as on-board charger (OBC) and water heater, etc.) in the vehicle V can also use thick film resistors similarly to avoid the occurrence of electro-corrosion phenomena.

[0034] The technical content and technical features of the present invention have been disclosed above. However, it can be understood that under the creative concept of the present invention, those skilled in the art can make various changes and improvements to the above-disclosed concept, but all belong to the protection scope of the present invention.

[0035] The description of the above embodiments is exemplary rather than restrictive, and the protection scope of the present invention is determined by the claims.

Claims

1. A battery pack for a vehicle, characterized in that, Comprising: A box body (41); A plurality of battery modules (1), the plurality of battery modules (1) being arranged in the box body (41); And A battery management system (3), the battery management system (3) being arranged in the box body (41) and including a main control unit (33) and a plurality of slave control units (31, 32) arranged in parallel. One end of each of the plurality of slave control units (31, 32) is connected to the corresponding battery module (1) among the plurality of battery modules (1), and the other end is connected to the main control unit (33); Wherein, a thick film resistor is provided on the circuit board of the main control unit (33), and / or a thick film resistor is provided on the circuit board of at least one of the plurality of slave control units (31, 32).

2. The battery pack according to claim 1, characterized in that, Each of the plurality of slave control units (31, 32) is connected to the corresponding battery module (1) through a copper busbar (62), and the thick film resistor is provided when the voltage of the copper busbar (62) is greater than 60V.

3. The battery pack according to claim 1 or 2, characterized in that, The maximum overload voltage of the thick film resistor is set to 400V.

4. The battery pack according to claim 1 or 2, characterized in that, The tolerance of the thick film resistor is set to ±0.1%.

5. The battery pack according to claim 1 or 2, characterized in that, The circuit board is coated with an IPX7-level nano material waterproof coating that at least covers the thick film resistor.

6. The battery pack according to claim 5, wherein, The thickness of the nano material waterproof coating is between 50 microns and 60 microns.

7. The battery pack according to claim 1 or 2, characterized in that, The housing covering the circuit board of the main control unit (33) and / or the housing covering the circuit board of at least one of the plurality of slave control units (31, 32) is set to an IPX7-level sealed structure.

8. A vehicle (V), characterized in that, The vehicle (V) includes the battery pack (A) according to any one of claims 1 to 7.

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