CN212783690U

CN212783690U - Bus bar and battery module

Info

Publication number: CN212783690U
Application number: CN202021922425.5U
Authority: CN
Inventors: 史忠发; 周知义
Original assignee: Microvast Power Systems Huzhou Co Ltd; Microvast Inc
Current assignee: Microvast Power Systems Huzhou Co Ltd; Microvast Holdings Inc
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2021-03-23
Anticipated expiration: 2030-09-04

Abstract

The utility model provides a total utmost point busbar, include the main part and follow the one end of main part is buckled and is extended the kink that forms, the main part with the kink aluminium is made, the surface covering of kink has the copper layer. The utility model provides a total utmost point busbar, through the surface at the kink cover one deck copper layer, make total utmost point busbar combine to form the copper aluminium composite bed by copper layer and aluminium lamination at local position (kink promptly) for the kink has good toughness, prevents the kink rupture, makes the kink have electric conductive property in addition good, advantage that the ability of overflowing is strong, and the copper layer only covers on the surface of kink simultaneously, and the surface that is compared in whole total utmost point busbar all covers the structure on copper layer, the utility model has the advantages of light in weight, with low costs. The utility model also provides a battery module.

Description

Bus bar and battery module

Technical Field

The utility model belongs to the technical field of the battery technique and specifically relates to a total utmost point busbar and battery module are related to.

Background

With the application and large-area popularization of electric automobiles, batteries are used as core parts of the electric automobiles, and higher requirements are put forward on the safety performance of the batteries. In order to meet the requirements of high voltage and high energy of batteries for electric vehicles, a plurality of batteries are generally required to be connected in series or in parallel, and in order to realize series and parallel connection of a plurality of batteries, a material with excellent conductivity is required to be used as a battery bus bar, and the quality of electrical connection between all bus bars in a battery module has a very important influence on the service performance, service life and safety performance of the battery module.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a total utmost point busbar and battery module through covering the copper layer in kink department, makes the kink have good toughness, prevents that the kink from breaking in the use, makes the kink have good electric conductive property and ability of overflowing moreover.

The utility model provides a total utmost point busbar, include the main part and follow the one end of main part is buckled and is extended the kink that forms, the main part with the kink aluminium is made, the surface covering of kink has the copper layer.

Further, the outer surface of the copper layer is covered with a first nickel layer.

Further, the outer surface of the main body portion is also covered with the first nickel layer.

Further, the thickness of the bent part is 1.500-4.000 mm; or the thickness of the bent part is 2.000-3.000 mm.

Further, the thickness of the copper layer is 0.200-1.500 mm.

Further, the thickness of the first nickel layer is 0.005-0.010 mm.

Further, the coverage area of the copper layer accounts for 20% -40% of the total outer surface area of the main body part and the bent part.

Further, the coverage area of the copper layer accounts for 20% -30% of the total outer surface area of the main body part and the bending part.

The utility model also provides a battery module, including a plurality of groups of batteries, a plurality of groups of batteries include first group battery and second group battery at least, with first group battery is connected with first total utmost point busbar, with the second group battery is connected with second total utmost point busbar, first total utmost point busbar with second total utmost point busbar is above arbitrary one total utmost point busbar.

Further, the battery module still includes the outside busbar, the relative both ends of outside busbar are equipped with first portion of bending and the second portion of bending respectively, first portion of bending with the kink of first total utmost point busbar contacts, the second portion of bending with the kink of second total utmost point busbar contacts.

Further, the battery module still includes the outside busbar, the relative both ends of outside busbar are equipped with first portion of bending and the second portion of bending respectively, the lower surface of first portion of bending with the upper surface of the kink of first total utmost point busbar contacts, the lower surface of second portion of bending with the upper surface of the kink of second total utmost point busbar contacts.

Furthermore, a nickel sheet is attached and fixed on the surface of the first bending part and the surface of the second bending part or a second nickel layer is covered on the surface of the first bending part and the surface of the second bending part.

Furthermore, the upper surface and the lower surface of the first bending part and the upper surface and the lower surface of the second bending part are respectively fixedly attached with a nickel sheet or covered with a second nickel layer.

The utility model provides a total utmost point busbar, through the surface at the kink cover the copper layer, make total utmost point busbar combine to form the copper aluminium composite bed by copper layer and aluminium lamination at local position (kink promptly) for the kink has good toughness, prevents the kink rupture, makes the kink have electric conductive property in addition good, advantage that the ability of overflowing is strong, and the copper layer only covers on the surface of kink simultaneously, and the surface that is compared in whole total utmost point busbar all covers the structure on copper layer, the utility model has the advantages of light in weight, with low costs.

Drawings

Fig. 1 is a schematic structural diagram of a bus bar of the embodiment of the present invention.

Fig. 2 is a schematic structural diagram of an external bus bar according to an embodiment of the present invention.

Fig. 3 is a schematic view illustrating a connection between a bus bar and an external bus bar according to an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a battery module according to an embodiment of the present invention.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

As shown in fig. 1, the total pole busbar 1 provided by the embodiment of the present invention includes a main body portion 11 and a bending portion 12 formed by bending and extending from one end of the main body portion 11, the main body portion 11 and the bending portion 12 are made of aluminum, an outer surface of the bending portion 12 is covered with a copper layer 13, that is, the copper layer 13 is only covered on an outer surface of the bending portion 12.

Preferably, the outer surface of the copper layer 13 is covered with a first nickel layer 14.

Specifically, in the field of electricity, a busbar (also called as a bus, a bus bar, or the like) is generally used for connecting a plurality of electrical lines, the number of cable connections can be greatly reduced by adopting a busbar-type electrical connection structure, the problem of high-density layout of an electronic system is solved, and meanwhile, the busbar has the advantages of low inductance, strong anti-interference capability, good high-frequency filtering effect, high reliability, space saving, simplicity and quickness in assembly, and the like.

In the total pole bus bar 1 provided by the embodiment of the present invention, the main body portion 11 and the bent portion 12 are made of aluminum, that is, the aluminum layer is used as a base layer, and the copper layer 13 covers only the outer surface of the bent portion 12, so that the total pole bus bar 1 has the advantages of light weight and low cost; meanwhile, the cross-sectional area of the bent portion 12 of the bus bar 1 is smaller than the cross-sectional areas of other positions of the bus bar 1, so that the overcurrent capacity of the bent portion 12 is weak, the copper layer 13 covers the outer surface of the bent portion 12, and the good conductive performance of the copper layer 13 is utilized, so that the conductive performance and the overcurrent capacity of the bus bar 1 are enhanced, and meanwhile, the copper layer 13 has good toughness, so that the bent portion 12 has good toughness, and the bent portion 12 is prevented from being broken.

Meanwhile, as the joint of the total pole bus bar 1 and other bus bars is easy to generate galvanic corrosion (galvanic corrosion is also called contact corrosion, which is electrochemical corrosion generated by two different metals contacting with each other and simultaneously being in electrolyte, and since the galvanic corrosion spontaneously constitutes a galvanic cell, the corroded metals are more active metals, for example, a copper plate connected by an iron rivet generates galvanic corrosion in humid air, iron is more active than copper to be used as an anode, and iron is dissolved and corroded), the outer surface of the copper layer 13 is covered with the first nickel layer 14, and since nickel is more active than copper and the first nickel layer 14 wraps the copper layer 13, the copper layer 13 can be prevented from being exposed to the outside and contacting with water or other electrolytes in the environment, so that the copper layer 13 is protected from corrosion.

Preferably, the outer surface of the main body 11 is also covered with the first nickel layer 14, that is, the outer surface of the entire bus bar 1 is covered with the first nickel layer 14, and the first nickel layer 14 covers the outer surface of the entire bus bar 1, so as to prevent galvanic corrosion of the entire bus bar 1. The coverage area of the first nickel layer 14 can be determined according to the actual requirement and the cost budget, and is not limited herein.

Preferably, the first nickel layer 14 is formed by plating nickel on the surface of the bus bar 1 by means of electroless plating.

Preferably, the thickness of the bent portion 12 is 1.500-4.000 mm.

More preferably, the thickness of the bent portion 12 is 2.200-2.600 mm.

Preferably, the copper layer 13 has a thickness of 0.200-1.500 mm.

More preferably, the copper layer 13 has a thickness of 0.300-0.800 mm.

Preferably, the thickness of the first nickel layer 14 is 0.005-0.010 mm.

Preferably, the coverage area of the copper layer 13 occupies 20 to 40% of the total outer surface area of the main body portion 11 and the bent portion 12.

More preferably, the coverage area of the copper layer 13 occupies 20% to 30% of the total outer surface area of the main body portion 11 and the bent portion 12.

Preferably, the material of the main body 11 and the bent portion 12 is 1060 aluminum, and the material of the copper layer 13 is T2 red copper. The bending part 12 and the copper layer 13 are combined together in an oxygen-free metallurgical mode, so that the bending part 12 and the copper layer 13 have good combination rate, the bus bar 1 has good conductivity, and the problems of oxidation and crystallization of two nonferrous metals with different properties between transition layers are solved fundamentally.

Preferably, the mass ratio of copper to aluminum in the bus bar 1 (copper-aluminum composite bus bar) provided by the embodiment is 1: 8-1: 32, that is, the copper content is 3% -11%.

Further, the top end of the bending part 12 is provided with a first through hole 15 for screwing and fixing with other busbars; the main body 11 is provided with a through slot 16 along the length direction for connecting with a tab (not shown) of a battery, specifically, the tab of the battery is bent after passing through the through slot 16, so that the tab is attached to the main body 11, and then is welded and fixed with the main body 11.

Comparing the overall performance of the bus bar 1 (hereinafter, a copper-aluminum composite bus bar is described, wherein the mass ratio of copper to aluminum of the copper-aluminum composite bus bar is 1:8) and the copper bus bar (pure copper) and the aluminum bus bar (pure aluminum), the result is as follows:

1. resistivity comparisons of three busbars: the copper busbar (0.018) < the copper-aluminum composite busbar (0.026) < the aluminum busbar (0.030), wherein the unit of resistivity is omega.m;

2. conductivity comparisons of three busbars: the copper busbar (97.5%) is more than the copper-aluminum composite busbar (73%) is more than the aluminum busbar (59%);

3. the overcurrent capacities of the three busbars were compared: the copper bus bar is larger than the copper-aluminum composite bus bar and the aluminum bus bar;

4. IIIDensity comparison of seed busbars: copper busbar (8.89) > copper-aluminum composite busbar (3.945) > aluminum busbar (2.6), wherein the density unit is g/cm³；

5. Contact resistance comparison of three busbars: the copper bus bar is approximately equal to the copper-aluminum composite bus bar and is less than the aluminum bus bar;

6. the comprehensive cost performance of the three busbars is compared: the copper-aluminum composite bus bar is larger than the aluminum bus bar and the copper bus bar.

From the comparison results, the total pole bus bar 1 (copper-aluminum composite bus bar) provided by the embodiment has good conductivity and low cost, and meanwhile, the density of the copper-aluminum composite bus bar is close to that of the aluminum bus bar, so the weight is light, and the copper-aluminum composite bus bar has better overcurrent capacity compared with the aluminum bus bar, and meanwhile, because the copper-aluminum composite bus bar has good toughness, the bending part 12 is not easy to break, so the comprehensive cost performance of the copper-aluminum composite bus bar is higher than the cost performance of other two bus bars.

As shown in fig. 4, the embodiment of the present invention further provides a battery module 3, which includes a plurality of battery packs, the plurality of battery packs at least include a first battery pack 31 and a second battery pack 32, the first battery pack 31 is connected with a first bus bar (not shown), the first bus bar is connected with the tab of the first battery pack 31, the second battery pack 32 is connected with a second bus bar (not shown), the second bus bar is connected with the tab of the second battery pack 32, and the first bus bar and the second bus bar are the bus bar 1.

Further, as shown in fig. 2 to 4, the battery module 3 further includes an external bus bar 2, opposite ends of the external bus bar 2 are respectively provided with a first bending portion 21 and a second bending portion 22, the first bending portion 21 is in contact with the bending portion 12 of the first bus bar, and the second bending portion 22 is in contact with the bending portion 12 of the second bus bar.

Preferably, the external bus bars 2 are copper bus bars.

As shown in fig. 2 and 3, in the present embodiment, the lower surface of the first bending portion 21 contacts the upper surface of the bending portion 12 of the first bus bar, and the lower surface of the second bending portion 22 contacts the upper surface of the bending portion 12 of the second bus bar. The top of the first bending part 21 is provided with a second through hole 211, the top of the second bending part 22 is provided with a third through hole 221, the first bending part 21 is fixedly connected with the bending part 12 of the first bus bar in a threaded manner, and the second bending part 22 is fixedly connected with the bending part 12 of the second bus bar in a threaded manner; meanwhile, the first bus bar is connected with the tab of the first battery pack 31, and the second bus bar is connected with the tab of the second battery pack 32, that is, the first battery pack 31 and the second battery pack 32 are electrically connected through the first bus bar, the external bus bar 2 and the second bus bar, and through the connection mode, series connection or parallel connection among a plurality of battery packs can be realized.

Further, a nickel sheet 23 is attached to the surface of the first bending portion 21 and the surface of the second bending portion 22 or covered with a second nickel layer (not shown). In the present embodiment, the upper surface and the lower surface of the first bending portion 21 and the upper surface and the lower surface of the second bending portion 22 are respectively fixed with the nickel sheet 23, and the nickel sheet 23 can further prevent galvanic corrosion from occurring at the position where the external bus bar 2 is connected to the bus bar 1.

Preferably, the thickness of the nickel sheet 23 or second nickel layer is 0.1 mm. Of course, other thicknesses of nickel sheet 23 or second nickel layer may also be selected, and are not limited herein.

The embodiment of the utility model provides a bus bar 1 and battery module 3's advantage lies in:

1. the copper layer 13 is covered at the bent part 12, so that the bus bar 1 has good overcurrent capacity and conductivity;

2. the bending part 12 has good toughness by covering the copper layer 13 at the bending part 12, so that the bending part 12 is prevented from being broken;

3. in this embodiment, the copper layer 13 only covers the outer surface of the bending portion 12, and compared with a structure in which the outer surface of the entire bus bar is covered with the copper layer, this embodiment reduces the consumption of the copper material, reduces the weight of the bus bar 1, and reduces the cost;

4. by covering the first nickel layer 14 on the surface of the total pole bus bar 1, galvanic corrosion at the position where the total pole bus bar 1 is contacted with the external bus bar 2 can be prevented, and meanwhile, the nickel sheets 23 are attached and fixed to the surfaces of the bending parts 21/22 at the two opposite ends of the external bus bar 2 or covered with the second nickel layer, galvanic corrosion at the position where the external bus bar 2 is contacted with the total pole bus bar 1 can be further prevented;

5. the embodiment of the utility model provides a total utmost point busbar 1 compact structure compares in aluminium commentaries on classics copper tailor-welding connection structure's busbar, has the little advantage of occupation space.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The bus bar is characterized by comprising a main body part (11) and a bent part (12) formed by bending and extending one end of the main body part (11), wherein the main body part (11) and the bent part (12) are made of aluminum, and the outer surface of the bent part (12) is covered with a copper layer (13).

2. Bus bar according to claim 1, characterized in that the outer surface of the copper layer (13) is covered with a first nickel layer (14).

3. Bus bar as set forth in claim 2, characterized in that the outer surface of the main body (11) is also covered with the first nickel layer (14).

4. Bus bar according to claim 2, characterized in that the thickness of the first nickel layer (14) is 0.005-0.010 mm.

5. The bus bar of claim 1, wherein the bent portion (12) has a thickness of 1.500-4.000 mm.

6. The bus bar of claim 1, wherein the copper layer (13) has a thickness of 0.200 to 1.500 mm.

7. The bus bar of claim 1, wherein the copper layer (13) has a coverage area that is 20-40% of a total outer surface area of the main body portion (11) and the bent portion (12).

8. The bus bar of claim 7, wherein the copper layer (13) has a coverage area that is 20-30% of a total outer surface area of the main body portion (11) and the bent portion (12).

9. A battery module comprising a plurality of battery packs, which comprise at least a first battery pack (31) and a second battery pack (32), to which a first bus bar is connected to the first battery pack (31) and a second bus bar is connected to the second battery pack (32), characterized in that the first and the second bus bar are each a bus bar (1) according to any one of claims 1 to 8.

10. The battery module according to claim 9, further comprising an external bus bar (2), wherein opposite ends of the external bus bar (2) are respectively provided with a first bent portion (21) and a second bent portion (22), the first bent portion (21) being in contact with the bent portion (12) of the first bus bar, and the second bent portion (22) being in contact with the bent portion (12) of the second bus bar.

11. The battery module according to claim 10, wherein the surface of the first bent portion (21) and the surface of the second bent portion (22) are attached with a nickel sheet (23) or covered with a second nickel layer.