CN111477825A

CN111477825A - Battery module and have its battery module and car

Info

Publication number: CN111477825A
Application number: CN202010366522.9A
Authority: CN
Inventors: 杨重科; 冯帅; 赵亮; 李成亮; 翁志福
Original assignee: Kunshan Bao Innovative Energy Technology Co Ltd
Current assignee: Kunshan Bao Innovative Energy Technology Co Ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2020-07-31

Abstract

The invention discloses a battery module, a battery module with the same and an automobile, wherein the battery module comprises a plurality of stacked bodies, each stacked body comprises a plurality of stacked electric cores, positive pole lug end parts of the electric cores are stacked and welded to form a positive pole lug area, negative pole lug end parts of the electric cores are stacked and welded to form a negative pole lug area, and the positive pole lug area of one stacked body and the negative pole lug area of the other stacked body in two adjacent stacked bodies are stacked and welded to form a cascading welding area. Therefore, the battery module saves connecting accessory copper bars for connecting the battery cells in parallel and connecting the stacked bodies in series, so that the cost and the weight of the module are reduced, and the space utilization rate is improved.

Description

Battery module and have its battery module and car

Technical Field

The invention belongs to the field of batteries, and particularly relates to a battery module, a battery module with the same and an automobile.

Background

With the continuous popularization of new energy automobiles, the use requirement of power batteries in the new energy automobiles becomes higher and higher. Particularly, the requirement of the user on the continuous mileage of the new energy automobile is continuously improved. The common new energy automobile, as a power battery pack of the new energy automobile, is more than 1 meter in both the length direction and the width direction; in the current market, the length of the battery modules is generally about 0.3 m, so at least 3 or even more battery modules need to be arranged in the power battery pack.

Set up a plurality of battery module, all need add fixed knot to every battery module and construct, simultaneously, need carry out power connection through the power connecting piece of peripheral hardware between two adjacent battery modules. The battery module has more mounting structures, so that not only is the cost increased, but also the overall weight is increased; simultaneously, in single module volume, mounting structure has taken more inner space, causes power battery module, and battery package whole capacity reduces, and battery module sets up more in the battery package, and the space is extravagant just more. In addition, because a plurality of external power connecting pieces are needed to be arranged for power connection, the internal resistance and the cost are increased, and the internal consumption and the cost of the power battery pack in use are improved.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, an object of the present invention is to provide a battery module, a battery module having the same, and an automobile, in which connection accessory copper bars for connecting cells in parallel and stacking bodies in series are omitted, so that the cost and weight of the module are reduced, and the space utilization rate is improved.

In one aspect of the present invention, a battery module is provided. According to an embodiment of the present invention, the battery module includes: the stacking body comprises a plurality of stacked electric cores, the positive pole lug end portions of the electric cores are welded in a stacking mode to form positive pole lug areas, the negative pole lug end portions of the electric cores are welded in a stacking mode to form negative pole lug areas, and the positive pole lug areas of one stacking body and the negative pole lug areas of the other stacking body in two adjacent stacking bodies are welded in a stacking mode to form a cascading welding area.

According to the battery module provided by the embodiment of the invention, a plurality of battery cells are stacked to form the stacked body, the end parts of the positive pole lugs of the battery cells in the same stacked body are stacked and welded to form the positive pole lug area, the end parts of the negative pole lugs of the battery cells in the same stacked body are stacked and welded to form the negative pole lug area, and the positive pole lug area of one stacked body and the negative pole lug area of the other stacked body in two adjacent stacked bodies are welded to form the cascade welding area.

In addition, the battery module according to the above embodiment of the present invention may further have the following additional technical features:

in some embodiments of the present invention, a first structural hole is formed on the positive electrode tab, a second structural hole is formed on the negative electrode tab, a first through channel formed by the first structural hole is formed in the positive electrode tab region, a second through channel formed by the second structural hole is formed in the negative electrode tab region, and an auxiliary connecting channel is formed in the cascade welding region by the first through channel and the second through channel, wherein an auxiliary connecting member is arranged in the auxiliary connecting channel. This can improve the reliability of the internal connection of the battery module.

In some embodiments of the present invention, the battery module further comprises: the protective shell for the first lug is clamped with the upper end and the lower end of the cascade welding area respectively, a first through hole and a first groove are formed in the protective shell for the first lug, and a first threaded hole is formed in the first groove. Therefore, on one hand, the tab protection area is protected, and on the other hand, the subsequent side plates are convenient to quickly position and assemble.

In some embodiments of the present invention, the battery module further comprises: the second utmost point ear protective housing, the second utmost point ear protective housing with be located the tip the pile body the anodal ear district or negative pole ear district joint, and be equipped with second through-hole and second recess on the second utmost point ear protective housing, be equipped with the second screw hole in the second recess. Therefore, on one hand, the positive pole ear area is protected, and on the other hand, the rapid positioning and assembly of the subsequent side plate are facilitated.

In some embodiments of the present invention, the battery module further comprises: the first side plate and the second side plate are respectively arranged on two side walls of the stacked body along the length direction of the battery module, the positions, corresponding to the first groove and the second groove, of the first side plate and the second side plate are respectively inwards protruded to form a first convex part and a second convex part, the first convex part is embedded in the first groove, a first connecting hole matched with the first threaded hole is formed in the first convex part, the second convex part is embedded in the second groove, a second connecting hole matched with the second threaded hole is formed in the second convex part, and a first opening hole and a second opening hole are respectively formed in the positions, corresponding to the first through hole and the second through hole, of the first side plate and the second side plate; separators provided at upper and lower ends of the stacked body in a length direction of the battery module; the first connecting piece penetrates through the first connecting hole to be matched with the first threaded hole; and the second connecting piece penetrates through the second connecting hole to be matched with the second threaded hole. From this, can realize the rapid Assembly of curb plate, improve battery module's reliability simultaneously.

In some embodiments of the present invention, the first side plate and/or the second side plate is provided with a concave-convex reinforcing rib. Therefore, the expansion force of the battery cell in the module can be effectively resisted.

In some embodiments of the invention, a buffer plate is provided between the first side plate and the stack and/or between the second side plate and the stack. Therefore, the battery cell protection device can play a role in protecting the battery cell.

In some embodiments of the present invention, a structural adhesive is disposed between two adjacent battery cells, between the stacked body and the buffer plate, and between the buffer plate and the first side wall and the second side wall, respectively. This can improve the reliability of the battery module.

In still another aspect of the present invention, a battery module is provided. According to an embodiment of the present invention, the battery module includes:

a plurality of the above battery modules;

the battery module comprises a first baffle and a second baffle, wherein the first baffle and the second baffle are arranged oppositely and at intervals, the plurality of battery modules are arranged between the first baffle and the second baffle, and third holes and fourth holes are respectively formed in the positions, corresponding to the first holes and the second holes, of the first baffle and the second baffle;

a third connector passing through the third opening, the first opening, and the first through hole;

a fourth connector passing through the fourth opening, the second opening, and the second through hole.

According to the battery module of the embodiment of the invention, the positions of the first baffle plate and the second baffle plate corresponding to the first opening and the second opening on the battery module are respectively provided with the third opening and the fourth opening, the third connecting piece is arranged to penetrate through the third opening, the first opening and the first through hole, and the fourth connecting piece is arranged to penetrate through the fourth opening, the second opening and the second through hole to realize the fixation of the plurality of battery modules, compared with the prior art that an external power connecting piece is required to be arranged between two adjacent battery modules for power connection, namely the plurality of battery modules are required to be connected by adopting a plurality of power connecting pieces, the power connecting piece is not required to be arranged between two adjacent battery modules in the battery module, but the connection of the plurality of battery modules can be realized by only adopting the third connecting piece and the fourth connecting piece, so that the use of the connecting pieces is reduced, and the cost and the weight of the battery module are reduced, the installation space is saved, the connection stability and the reliability of the power connecting piece do not need to be considered, and the connection internal resistance is reduced, so that the internal consumption of the battery module is reduced, and the automobile provided with the battery module has excellent continuous mileage.

In a third aspect of the present invention, an automobile is provided. According to an embodiment of the invention, the automobile is provided with the battery module. Thus, the automobile has excellent mileage.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a cell in a battery module according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a stack in a battery module according to one embodiment of the present invention;

fig. 3 is a partial structural view of a battery module according to an embodiment of the present invention;

fig. 4 is a schematic structural view of a stack in a battery module according to still another embodiment of the present invention;

fig. 5 is a partial structural view of a battery module according to still another embodiment of the present invention;

fig. 6 is a schematic structural view of a battery module according to still another embodiment of the present invention;

fig. 7 is a structural view of a first tab protective case in a battery module according to an embodiment of the present invention;

fig. 8 is a schematic structural view of a battery module according to still another embodiment of the present invention;

fig. 9 is a schematic structural view of a battery module according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In a first aspect of the invention, a battery module is presented. According to an embodiment of the present invention, referring to fig. 1 to 8, the battery module 100 includes a plurality of stacked bodies 1, the stacked body 1 includes a plurality of stacked battery cells 10, and preferably, the plurality of battery cells 10 are stacked by being bonded by a structural adhesive (not shown). Referring to fig. 1, the positive electrode end of the battery cell 10 forms a positive electrode tab 101, the negative electrode end of the battery cell 10 forms a negative electrode tab 102, and referring to fig. 2, the positive electrode tab 101 ends of the plurality of battery cells 10 in the same stacked body 1 are welded in a stacked manner to form a positive electrode tab zone 11, the negative electrode tab 102 ends of the plurality of battery cells 10 in the same stacked body 1 are welded in a stacked manner to form a negative electrode tab zone 11, and referring to fig. 2, the positive electrode tab zone 11 of one stacked body 1 in two adjacent stacked bodies 1 is welded with the negative electrode tab zone 12 of the other stacked body 1 to form a cascade welding zone 13. From this, compare in current battery module in electric core adoption copper bar carry out parallelly connected and two adjacent stacks adopt the copper bar to carry out the mode of establishing ties in the same stack, the battery module of this application has saved the parallelly connected and stack series connection annex copper bar of electric core to reduce the cost and the weight of module, improved space utilization. Specifically, the end parts of the positive electrode tab 101 and the negative electrode tab 102 of the plurality of battery cells 10 of the same stack 1 are welded in a stacked manner, and the positive electrode tab region 11 of one stack 1 and the negative electrode tab region 12 of the other stack 1 in two adjacent stacks 1 are welded in a stacked manner by laser welding or ultrasonic welding.

Further, the positive electrode tabs 101 of the plurality of battery cells 10 in the same stack 1 are bent according to the structure shown in fig. 2, and the end portions of the bent positive electrode tabs 101 are stacked to form a positive electrode ear region 11, the negative electrode tabs 102 of the plurality of battery cells 10 in the same stack 1 are also bent according to the structure shown in fig. 2, and the end portions of the bent negative electrode tabs 102 are stacked to form a negative electrode ear region 11, referring to fig. 4, a first structure hole 1011 is provided on the positive electrode tab 101, a second structure hole 1021 is provided on the negative electrode tab 102, the positive electrode ear region 11 is provided with a first through channel 103 formed by a plurality of first structure holes 1011, the negative electrode ear region 12 is provided with a second through channel 104 formed by a plurality of second structure holes 102, and referring to fig. 5, in the cascade welding region 13, the first through channel 103 on one stack 1 of two adjacent stacks 1 is communicated with the second through channel 104 on the other stack 1 to form an auxiliary connecting channel 105, an auxiliary connection member (not shown) is provided in the auxiliary connection passage 105. Specifically, the first structure holes 1011 are formed in the positive electrode tab 101, the second structure holes 1021 are formed in the negative electrode tab 102, the first structure holes 1011 are overlapped to form the first through channel 103 when the end portions of the positive electrode tabs 101 and the negative electrode tabs 102 of the plurality of battery cells 10 are welded in a stacking manner in the same stack body 1, the second structure holes 1011 are overlapped to form the second through channel 104, so that the rapid positioning when the positive electrode tabs 101 and the negative electrode tabs 102 are stacked is facilitated, the first through channel 103 and the second through channel 104 are overlapped to form the auxiliary connecting channel 105 when the positive electrode tab area 11 of one stack body 1 and the negative electrode tab area 12 of the other stack body 1 are welded in a stacking manner to form the cascade welding region 13 in the two adjacent stack bodies 1, the rapid positioning when the two adjacent stack bodies 1 form the cascade welding region 13 is facilitated, and the auxiliary connecting piece is arranged in the auxiliary connecting channel 105 of the cascade 13, so that the reliable connection of the two adjacent stack bodies 1 can be improved . It should be noted that the specific type of the auxiliary connecting member can be selected by those skilled in the art according to actual needs, as long as reliable connection between two adjacent stacked bodies 1 can be achieved, and the auxiliary connecting member can be a rivet or a bolt, for example.

Further, referring to fig. 6, the battery module 100 further includes a first tab protection housing 14 and a second tab protection housing 15, wherein the first tab protection housing 14 is respectively connected to the upper end and the lower end of the cascade welding region 13 in a snap-fit manner, that is, two first tab protection housings 14 are disposed at the cascade welding region 13, the two first tab protection housings 14 are respectively connected to the cascade tab region 13 from the upper end and the lower end of the battery module 100 in a snap-fit manner, referring to fig. 7, a first through hole 141 and a first groove 142 are disposed on the first tab protection housing 14, a first threaded hole 1421 is disposed in the first groove 142, referring to fig. 6, the second tab protection housing 15 is connected to the positive tab region 11 or the negative tab region 12 of the stack body 1 located at the end, a second through hole 151 and a second groove 152 are disposed on the second tab protection housing 15, and a second threaded hole 1521 is disposed in the second. It should be noted that, a person skilled in the art may select the number of the first through holes 141, the first grooves 142, the second through holes 151, and the second grooves 152 according to actual needs, and preferably, one first through hole 141 and one first groove 142 are provided on the first tab protection housing 14, two second through holes 151 and two second grooves 152 are provided on the second tab protection housing 15, the two second through holes 151 are symmetrically arranged, the two second grooves 152 are also symmetrically arranged, and the first grooves 142 and the second grooves 152 are both circular grooves, so as to guide the installation of subsequent side plates, thereby achieving rapid assembly. Specifically, the first tab protection housing 14 and the second tab protection housing 15 are made of insulating and flame-retardant plastic, such as PP, APS, PC, PA, and PA 66.

Further, referring to fig. 8, the battery module further includes a first side plate 16, a second side plate 17, a partition plate 18, a first connector (not shown), and a second connector (not shown).

Referring to fig. 8, the first side plate 16 and the second side plate 17 are respectively disposed on two side walls of the stack body 1 along the length direction of the battery module 100, and the first protrusion 162 and the second protrusion 172 are respectively formed on the first side plate 16 and the second side plate 17 at positions corresponding to the first groove 142 and the second groove 152, that is, the first protrusion 162 is formed on the first side plate 16 and the second side plate 17 at positions corresponding to the first groove 142, the second protrusion 172 is formed on the first side plate 16 and the second side plate 17 at positions corresponding to the second groove 152, the first protrusion 162 is fitted in the first groove 142, the first protrusion 162 is provided with a first connection hole 1621 matching with the first screw hole 1421, the second protrusion 172 is fitted in the second groove 152, and the second protrusion 172 is provided with a second connection hole 1721 matching with the second screw hole 1521, so that when the first side plate 16 and the second side plate 17 are disposed on two side walls of the stack body 1, the first side plate 162 is fitted in the first groove 142, and the second protrusion 172 is fitted in the second groove Two grooves 152 cooperate to realize the rapid assembly of first curb plate 16 and second curb plate 17, and the position that corresponds first through-hole 141 and second through-hole 151 on first curb plate 16 and the second curb plate 17 forms first trompil 161 and second trompil 171 respectively simultaneously, corresponds first through-hole 141's position on first curb plate 16 and the second curb plate 17 and all forms first trompil 161, corresponds second through-hole 151's position on first curb plate 16 and the second curb plate 17 and all forms second trompil 171.

Referring to fig. 8, separators 18 are provided at the upper and lower ends of the stack 1 in the lengthwise direction of the battery module 100, first connectors are coupled with the first screw holes 1421 through the first coupling holes 1621, and second connectors are coupled with the second screw holes 1521 through the second coupling holes 1721, thereby achieving reliable mounting of the first and second side plates 16 and 17. Preferably, the first side plate 16 and/or the second side plate 17 are provided with concave-convex reinforcing ribs (not shown), so that the expansion force of the battery cells in the module can be effectively resisted, and the first connecting piece and the second connecting piece are both bolts. Specifically, the first side plate 16 and the second side plate 17 are made of metal or plastic, the metal is made of aluminum, copper, iron and alloy materials thereof, the metal can be formed by punching, the plastic is thermosetting plastic such as SMC, the plastic has high strength, and the thermosetting material can be formed by injection molding.

Further, referring to fig. 8, a buffer plate 19 is disposed between the first side plate 16 and the stacked body 1 and/or between the second side plate 17 and the stacked body 1, and is used for providing a pre-tightening force for fixing the battery cell 10 during initial assembly of the stacked body 1 and absorbing an expansion force of the battery cell 10 at an end stage of use. It should be noted that, a person skilled in the art can select the material of the buffer plate 21 according to actual needs, and for example, the material may be insulating and flame retardant plastic, such as PP, APS, PC, PA66, and the like. While structural adhesives are provided between the stack 1 and the buffer plate 21, and between the buffer plate 21 and the first and second side walls 16 and 17, respectively, thereby improving the reliability of the battery module.

In still another aspect of the present invention, a battery module is provided. According to an embodiment of the present invention, referring to fig. 9, the battery module includes: the battery module 100, the first barrier 200, the second barrier 300, the third connection member 400, and the fourth connection member 500.

Referring to fig. 9, the battery module includes a plurality of battery modules 100, in which the connecting accessory copper bars of the battery cells connected in parallel and the stacked body connected in series are omitted, the plurality of battery modules 100 are sequentially arranged, the first openings 161 of the plurality of battery modules 100 are through, and the second openings 171 of the plurality of battery modules 100 are through.

Referring to fig. 9, the first barrier 200 and the second barrier 300 are disposed opposite to each other at intervals, the plurality of battery modules 100 are disposed between the first barrier 200 and the second barrier 300, the first barrier 200 and the second barrier 300 are respectively provided with a third opening 201 and a fourth opening 301 at positions corresponding to the first opening 161 and the second opening 171, that is, the first barrier 200 and the second barrier 300 are both provided with a third opening 201 at positions corresponding to the first opening 161, and the first barrier 200 and the second barrier 300 are both provided with a fourth opening 301 at positions corresponding to the second opening 171.

The third connector 400 passes through the third opening 201, the first opening 161 and the first through hole 141, and the fourth connector 500 passes through the fourth opening 301, the second opening 171 and the second through hole 151, so that the plurality of battery modules 100 can be fixed by using the third connector 400 and the fourth connector 500. Preferably, the third connector 400 and the fourth connector 500 each include a bolt 51 and a nut 52, taking the first baffle 200 close to the first side plate 16 of the plurality of battery modules 100 and the second baffle 300 close to the second side plate 17 of the plurality of battery modules 100 as an example, the bolt 51 sequentially passes through the third opening 201 on the first baffle 200, the first opening 161 on the first side plate 16, the first through hole 141 on the first tab protection housing 14, the first opening 161 on the second side plate 17 and the third opening 201 on the second baffle 300, and the nut 52 is disposed on a side of the second baffle 300 away from the first baffle 200 and is locked with the bolt 51 in a matching manner; the bolt 51 passes through the fourth hole 301 on the first baffle 200, the second hole 171 on the first side plate 16, the second through hole 151 on the second lug protective shell 15, the second hole 171 on the second side plate 17 and the fourth hole 301 on the second baffle 300, and the nut 52 is arranged on one side of the second baffle 300 far away from the first baffle 200 and is matched and locked with the bolt 51.

For need set up the power connecting piece of peripheral hardware and carry out the power connection between two adjacent battery modules among the prior art, a plurality of battery modules need adopt a plurality of power connecting pieces to connect promptly, need not set up the power connecting piece between two adjacent battery modules in the battery module of this application, but only adopt third connecting piece and fourth connecting piece can realize linking to each other of a plurality of battery modules, the connecting piece use has not only been reduced, and the cost and the weight of battery module have been reduced, installation space has been saved, need not to consider power connecting piece's connection stability and reliability simultaneously, the internal resistance of connection has been reduced, thereby reduce the internal consumption of battery module, and then make the car of installing this battery module have excellent continuous-time mileage. It should be noted that the features and advantages described above for the battery module are also applicable to the battery module, and are not described herein again.

In a third aspect of the present invention, an automobile is provided. According to an embodiment of the invention, the automobile is provided with the battery module. Preferably, the vehicle is a new energy vehicle. Thus, the automobile has excellent mileage. It should be noted that the features and advantages described above for the battery module are also applicable to the vehicle, and are not described herein again.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A battery module is characterized by comprising a plurality of stacked stacks, wherein each stacked stack comprises a plurality of stacked cells, positive pole lug ends of the cells are welded in a stacked mode to form a positive pole lug area, negative pole lug ends of the cells are welded in a stacked mode to form a negative pole lug area, and the positive pole lug area of one stacked stack and the negative pole lug area of the other stacked stack in two adjacent stacked stacks are welded in a stacked mode to form a cascading welding area.

2. The battery module as set forth in claim 1, wherein a first structural hole is formed in the positive electrode tab, a second structural hole is formed in the negative electrode tab, the positive electrode tab region is provided with a plurality of first through passages formed by the first structural hole, the negative electrode tab region is provided with a plurality of second through passages formed by the second structural hole, and the first through passages and the second through passages are communicated to form an auxiliary connecting passage in the cascade welding region, and an auxiliary connecting member is provided in the auxiliary connecting passage.

3. The battery module according to claim 1 or 2, characterized by further comprising: the protective shell for the first lug is clamped with the upper end and the lower end of the cascade welding area respectively, a first through hole and a first groove are formed in the protective shell for the first lug, and a first threaded hole is formed in the first groove.

4. The battery module of claim 3, further comprising: the second utmost point ear protective housing, the second utmost point ear protective housing with be located the tip the pile body the anodal ear district or negative pole ear district joint, and be equipped with second through-hole and second recess on the second utmost point ear protective housing, be equipped with the second screw hole in the second recess.

5. The battery module of claim 4, further comprising:

the first side plate and the second side plate are respectively arranged on two side walls of the stacked body along the length direction of the battery module, the positions, corresponding to the first groove and the second groove, of the first side plate and the second side plate are respectively inwards protruded to form a first convex part and a second convex part, the first convex part is embedded in the first groove, a first connecting hole matched with the first threaded hole is formed in the first convex part, the second convex part is embedded in the second groove, a second connecting hole matched with the second threaded hole is formed in the second convex part, and a first opening hole and a second opening hole are respectively formed in the positions, corresponding to the first through hole and the second through hole, of the first side plate and the second side plate;

separators provided at upper and lower ends of the stacked body in a length direction of the battery module;

the first connecting piece penetrates through the first connecting hole to be matched with the first threaded hole;

and the second connecting piece penetrates through the second connecting hole to be matched with the second threaded hole.

6. The battery module according to claim 5, wherein the first side plate and/or the second side plate is provided with a concave-convex reinforcing rib.

7. The battery module according to claim 5 or 6, characterized in that a buffer plate is provided between the first side plate and the stack and/or between the second side plate and the stack.

8. The battery module of claim 7, wherein structural adhesive is disposed between two adjacent cells, between the stacked body and the buffer plate, and between the buffer plate and the first side wall and the second side wall, respectively.

9. A battery module, comprising:

a plurality of the battery modules of any one of claims 1-8;

10. An automobile characterized by having the battery module according to claim 9.