CN111146383B

CN111146383B - Battery pack, lower shell and lower shell manufacturing method

Info

Publication number: CN111146383B
Application number: CN201911203736.8A
Authority: CN
Inventors: 周青华; 古惠南; 席忠民
Original assignee: Guangzhou Automobile New Energy Automobile Co Ltd
Current assignee: GAC Aion New Energy Automobile Co Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2024-02-02
Anticipated expiration: 2039-11-29
Also published as: CN111146383A

Abstract

The invention discloses a battery pack, a lower shell and a lower shell manufacturing method.A first pre-assembly is used for enabling the end parts of two longitudinal beams to be respectively positioned on the two ends of a rear cross beam; the two ends of the front cross beam are respectively positioned on the end parts of the two longitudinal beams through the second preassembly; then, the longitudinal beam and the rear cross beam are stably connected through the first connecting piece; the longitudinal beam and the front cross beam are stably connected through the second connecting piece; finally, the bottom plate structure is arranged in the frame to obtain the lower shell. Because the preassembly structure is adopted to replace manual supporting operation, dislocation or deviation between the structures due to hand shake in the frame assembling process is effectively avoided, the frame assembling process is stably carried out, and the structural accuracy of the lower shell is greatly improved. Meanwhile, in the manufacturing process, a connecting structure of a frame is adopted to replace a traditional welding mode, so that the lower shell is produced by a few-welding or non-welding process machine.

Description

Battery pack, lower shell and lower shell manufacturing method

Technical Field

The invention relates to the technical field of power batteries, in particular to a battery pack, a lower shell and a lower shell manufacturing method.

Background

With the increasing maturity of new energy technology, new energy automobiles are also gradually coming into the public view. The new energy automobile adopts non-traditional fuel as a power source, integrates the power control and driving technologies of the automobile, and forms a new technology and a new structure automobile. The main core technology of the new energy automobile is a battery module, and the safety and stability of the battery module directly determine the performance of the whole automobile.

The battery module is generally fixed to the vehicle body in the form of a battery pack. The battery pack mainly comprises an upper shell and a lower shell, wherein the upper shell is covered on the lower shell, and the battery module is arranged in the lower shell. Therefore, the structural performance of the lower case directly affects the stability and safety of the battery module.

In the traditional lower shell manufacturing process, a front cross beam, a longitudinal beam and a rear cross beam are sequentially connected in a welding mode to form a frame; and then welding the bottom plate structure on the frame, thereby obtaining the lower shell. However, in the manufacturing process, a welding manner is adopted, so that the manufacturing process of the lower shell becomes complex, and the production efficiency of the lower shell is seriously affected. Meanwhile, in the manufacturing process, the front cross beam, the longitudinal beam and the rear cross beam are easy to misplace or deviate when in alignment and match, so that the structural accuracy of the obtained lower shell is seriously reduced, and the stability and the safety of the battery module are seriously influenced.

Disclosure of Invention

Based on this, it is necessary to provide a battery pack, a lower case, and a lower case manufacturing method, which can simplify the manufacturing process, make the lower case be produced with little or no welding process, and improve the production efficiency of the lower case; meanwhile, the manufacturing precision of the lower shell is improved, the structural quality of the lower shell is improved, and the stable and safe operation of the battery module is ensured.

The technical scheme is as follows:

a lower housing comprising: the frame comprises a front cross beam, a longitudinal beam and a rear cross beam, wherein two ends of the front cross beam are respectively matched with two ends of the rear cross beam through the longitudinal beam, and an accommodating cavity is formed by enclosing the front cross beam and the rear cross beam; a preassembly structure comprising a first package positioned between an end of the longitudinal beam and an end of the rear cross beam and a second package positioned between an end of the longitudinal beam and an end of the front cross beam; the connecting structure comprises a first connecting piece and a second connecting piece, the first connecting piece is connected between the longitudinal beam and the rear cross beam, and the second connecting piece is connected between the longitudinal beam and the front cross beam; and the bottom plate structure is arranged in the accommodating cavity and is connected with the frame.

In the manufacturing process of the lower shell, the end parts of the two longitudinal beams are respectively positioned on the two ends of the rear cross beam through the first preassembly; and through the second pre-assembly, the two ends of the front cross beam are respectively positioned on the end parts of the two longitudinal beams, so that the pre-forming operation of the frame is completed. Then, the longitudinal beam and the rear cross beam are stably connected through the first connecting piece; the longitudinal beam and the front cross beam are stably connected through the second connecting piece, so that a stable frame is formed; finally, the bottom plate structure is arranged in the frame to obtain the lower shell. Because this scheme adopts the pre-installation structure for rear cross beam or front cross beam are aimed at on the longeron steadily, consequently, make the manufacturing process need not many people and support the assistance, greatly liberated the labour, make the frame assembly process become labour saving and time saving, be favorable to improving the production efficiency of lower casing. Meanwhile, due to the fact that the preassembled structure is adopted to replace manual supporting operation, dislocation or deviation between the structures due to shaking of hands in the frame assembling process is effectively avoided, the frame assembling process is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, a connecting structure of the frame is adopted to replace a traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few-welding or no-welding process machine, and the production efficiency of the lower shell is improved.

A battery pack comprising an upper housing and a lower housing as claimed in any one of the preceding claims, the upper housing covering the lower housing.

The battery pack adopts the lower shell, and in the manufacturing process, the end parts of the two longitudinal beams are respectively positioned on the two ends of the rear cross beam through the first pre-assembly; and through the second pre-assembly, the two ends of the front cross beam are respectively positioned on the end parts of the two longitudinal beams, so that the pre-forming operation of the frame is completed. Then, the longitudinal beam and the rear cross beam are stably connected through the first connecting piece; the longitudinal beam and the front cross beam are stably connected through the second connecting piece, so that a stable frame is formed; finally, the bottom plate structure is arranged in the frame to obtain the lower shell. Because this scheme adopts the pre-installation structure for rear cross beam or front cross beam are aimed at on the longeron steadily, consequently, make the manufacturing process need not many people and support the assistance, greatly liberated the labour, make the frame assembly process become labour saving and time saving, be favorable to improving the production efficiency of lower casing. Meanwhile, due to the fact that the preassembled structure is adopted to replace manual supporting operation, dislocation or deviation between the structures due to shaking of hands in the frame assembling process is effectively avoided, the frame assembling process is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, a connecting structure of the frame is adopted to replace a traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few-welding or no-welding process machine, and the production efficiency of the lower shell is improved.

The lower shell manufacturing method comprises the following steps: positioning the ends of the two longitudinal beams on the two ends of the rear cross beam respectively through a first pre-assembly; positioning two ends of the front cross beam at the end parts of the two longitudinal beams respectively through a second pre-assembly to finish the pre-forming operation; after preforming, connecting first connecting pieces between the longitudinal beams and the rear cross beams respectively, so that the two longitudinal beams are connected with the rear cross beams respectively; connecting second connecting pieces between the longitudinal beams and the front cross beam respectively, so that the two longitudinal beams are connected with the front cross beam respectively to obtain a frame; after the frame is obtained, the bottom plate structure is arranged in the frame.

In the manufacturing method of the lower shell, in the manufacturing process, the end parts of the two longitudinal beams are respectively positioned on the two ends of the rear cross beam through the first preassembly; and through the second pre-assembly, the two ends of the front cross beam are respectively positioned on the end parts of the two longitudinal beams, so that the pre-forming operation of the frame is completed. Then, the longitudinal beam and the rear cross beam are stably connected through the first connecting piece; the longitudinal beam and the front cross beam are stably connected through the second connecting piece, so that a stable frame is formed; finally, the bottom plate structure is arranged in the frame to obtain the lower shell. Because this scheme adopts the pre-installation structure for rear cross beam or front cross beam are aimed at on the longeron steadily, consequently, make the manufacturing process need not many people and support the assistance, greatly liberated the labour, make the frame assembly process become labour saving and time saving, be favorable to improving the production efficiency of lower casing. Meanwhile, due to the fact that the preassembled structure is adopted to replace manual supporting operation, dislocation or deviation between the structures due to shaking of hands in the frame assembling process is effectively avoided, the frame assembling process is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, a connecting structure of the frame is adopted to replace a traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few-welding or no-welding process machine, and the production efficiency of the lower shell is improved.

Drawings

FIG. 1 is a perspective view of a lower housing structure according to an embodiment of the invention;

FIG. 2 is an exploded view of a lower housing structure according to an embodiment of the present invention;

FIG. 3 is an enlarged schematic view of the structure of FIG. 2 at circle A;

FIG. 4 is a schematic view of a frame structure according to an embodiment of the invention;

FIG. 5 is a schematic view showing the cooperation of the side member, the rear cross member and the first connecting member according to an embodiment of the present invention;

FIG. 6 is a schematic illustration showing a portion of the side member, rear cross member and first connector according to an embodiment of the present invention;

FIG. 7 is a schematic view of a partial explosion of the mating structure of the side rail, rear cross rail and first connector of FIG. 6;

FIG. 8 is a schematic diagram illustrating the mating of a stringer, a first package, and a rear cross member in accordance with an embodiment of the present invention;

FIG. 9 is a second schematic illustration of the mating of a stringer, a first package, and a rear cross member according to an embodiment of the present invention;

FIG. 10 is a schematic view illustrating the mating of the front cross member, the side member and the second connecting member according to an embodiment of the present invention;

FIG. 11 is a schematic view of a second connector according to an embodiment of the invention;

FIG. 12 is an exploded view of a front cross member, a side rail and a second package assembly according to an embodiment of the present invention;

FIG. 13 is a schematic view of a front cross member according to an embodiment of the present invention;

FIG. 14 is a partial schematic view of an end of a stringer mated with a second end seal in accordance with an embodiment of the present invention;

FIG. 15 is a schematic view of a middle rail according to an embodiment of the present invention;

FIG. 16 is a schematic view of a first mounting member according to an embodiment of the invention;

FIG. 17 is a schematic view of an end structure of a center sill according to an embodiment of the present invention;

FIG. 18 is a schematic view of a second mounting member according to an embodiment of the present invention;

FIG. 19 is a schematic view of another end of a center sill according to an embodiment of the present invention;

FIG. 20 is another view of the lower housing structure according to an embodiment of the present invention;

FIG. 21 is a cross-sectional view of the lower housing of FIG. 20 taken along the B-B direction;

FIG. 22 is an enlarged schematic view of the structure at circle C in FIG. 21;

FIG. 23 is an enlarged schematic view of the structure at circle D in FIG. 21;

FIG. 24 is an enlarged schematic view of the structure at the circle E in FIG. 21;

fig. 25 is a flowchart illustrating a lower case manufacturing method according to an embodiment of the invention.

Detailed Description

The present invention will be further described in detail with reference to the drawings and the detailed description, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The terms "first" and "second" in this specification do not denote a particular quantity or order, but rather are used for distinguishing between similar or identical items.

In one embodiment, referring to fig. 1, 2, 4, 7 and 12, a lower housing includes: the frame 100, the pre-assembled structure 400, the connection structure 200, and the base plate structure 300. The frame 100 includes a front cross member 110, a side member 120, and a rear cross member 130. The front cross member 110 is fitted at both ends thereof to both ends of the rear cross member 130 through the side members 120, respectively, and encloses the receiving chamber 140. The package structure 400 includes a first package 410 and a second package 430. The first package 410 is positioned between the end of the longitudinal beam 120 and the end of the rear cross beam 130. The second package 430 is positioned between the end of the side rail 120 and the end of the front cross rail 110. The connection structure 200 includes a first connection member 210 and a second connection member 220. The first connector 210 is connected between the side member 120 and the rear cross member 130. The second connector 220 is connected between the side member 120 and the front cross member 110. The base plate structure 300 is fitted into the receiving chamber 140 and coupled to the rim 100.

The lower case described above, during the manufacturing process, allows the ends of the two stringers 120 to be positioned on both ends of the rear cross member 130, respectively, through the first package 410; the second package 430 is then used to position the two ends of the front cross member 110 at the ends of the two stringers 120, respectively, so that the pre-forming operation of the frame 100 is completed. Then, the longitudinal beam 120 and the rear cross beam 130 are stably connected through the first connector 210; the side members 120 are stably connected with the front cross member 110 by the second connection members 220 to form a stable frame 100; finally, the bottom plate structure 300 is installed in the rim 100 to obtain the lower housing. Because the preassembly structure 400 is adopted in the embodiment, the rear cross beam 130 or the front cross beam 110 is stably aligned on the longitudinal beam 120, so that the assistance of supporting by multiple persons is not needed in the manufacturing process, the labor force is greatly liberated, the assembling process of the frame 100 is time-saving and labor-saving, and the production efficiency of the lower shell is improved. Meanwhile, due to the adoption of the preassembled structure 400, manual supporting operation is replaced, dislocation or offset between the structures due to hand shake in the assembling process of the frame 100 is effectively avoided, the assembling process of the frame 100 is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, the connecting structure 200 of the frame is adopted to replace the traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few welding or no welding process machine, and the production efficiency of the lower shell is improved.

Alternatively, the first connector 210 is connected to the longitudinal beam 120 and the rear cross beam 130 by bolting, riveting, pinning or other means. The second connector 220 is connected to the longitudinal beam 120 and the front cross beam 110 by bolting, riveting, pinning or other means.

Specifically, the sealant is disposed between the first package 410 and the end portion of the longitudinal beam 120, and the sealant is also disposed between the first package 410 and the end portion of the rear cross beam 130, so that the end portion of the longitudinal beam 120 and the end portion of the rear cross beam 130 are effectively sealed by the first package 410, so that a plurality of internal chambers of the longitudinal beam 120 and the rear cross beam 130 are independently opened, and water is prevented from flowing into the whole chamber due to water flowing into one of the chambers of the longitudinal beam 120 and the rear cross beam 130, and the waterproof performance of the frame 100 is improved. Meanwhile, a sealant is provided between the second package 430 and the end of the side member 120, and a sealant is also provided between the second package 430 and the end of the front cross member 110.

Further, referring to fig. 7, 8 and 9, the opposite sides of the first package 410 are respectively provided with a first protrusion 411 and a second protrusion 412, the longitudinal beam 120 is provided with a first jack 1251 in positioning engagement with the first protrusion 411, and the rear cross member 130 is provided with a second jack 135 in positioning engagement with the second protrusion 412. Thus, the longitudinal beam 120 is stably positioned on the rear cross beam 130 by the positioning fit of the first protrusion 411 and the first jack 1251 and the positioning fit of the second protrusion 412 and the second jack 135.

Specifically, the first package 410, the first protrusion 411, and the second protrusion 412 are integrally formed. Thus, the manufacturing process is simplified, and the production period is shortened. At the same time, it is also advantageous to improve the structural strength of the first package 410.

In one embodiment, referring to fig. 8, the first protrusions 411 are more than two. More than two first protrusions 411 are arranged on the first package 410 at intervals, and a first clamping groove 413 is formed between two adjacent first protrusions 411 and the first package 410. The longitudinal beam 120 is provided with a first partition 125, the first partition 125 divides the interior of the longitudinal beam 120 into more than two first jacks 1251, and when the first protrusions 411 are inserted into the first jacks 1251, the first clamping grooves 413 are clamped into the first partition 125. In this way, the first protrusion 411 is matched with the first receptacle 1251, and the first spacer 125 is matched with the first clamping groove 413, so that the longitudinal beam 120 and the first package 410 are mutually interweaved and matched, and the binding force between the first package 410 and the longitudinal beam 120 is greatly improved.

In one embodiment, referring to fig. 9, the number of the second protrusions 412 is more than two. More than two second protrusions 412 are disposed on the first package 410 at intervals, and a second clamping groove 414 is formed between two adjacent second protrusions 412 and the first package 410. The rear cross member 130 is provided with a second partition 136, the second partition 136 divides the rear cross member 130 into more than two second insertion holes 135, and when the second protrusions 412 are inserted into the second insertion holes 135, the second clamping grooves 414 are clamped into the second partition 136. In this way, the second protrusion 412 is matched with the second jack 135, and the second spacer 136 is matched with the second slot 414, so that the rear beam 130 and the first package 410 are mutually interweaved and matched, and the binding force between the first package 410 and the rear beam 130 is greatly improved.

Further, referring to fig. 9, the first protrusion 411 is disposed opposite to the second slot 414. The first protrusion 411 is provided with a first fixing hole 4111, the first fixing hole 4111 penetrates through the bottom of the second clamping groove 414, and the second partition 136 is provided with a second fixing hole 1361 opposite to the first fixing hole 4111. As can be seen, when the second protrusion 412 is inserted into the second insertion hole 135 and the second partition 136 is snapped into the second clipping slot 414, the fixing members respectively penetrate into the first fixing hole 4111 and the second fixing hole 1361, so that the first package 410 is stably connected to the rear cross member 130. The fixing piece can be a bolt, a screw, a pin, a rivet or other fixing parts.

Further, referring to fig. 9, the longitudinal beam 120 is further provided with a third fixing hole 124 opposite to the first fixing hole 4111. After the rear cross member 130, the first package 410, and the side member 120 are preformed, the worker may insert the fixing members into the third fixing holes 124, the first fixing holes 4111, and the second fixing holes 1361, respectively, to complete the preforming operation between the rear cross member 130, the first package 410, and the side member 120. In particular, in the present embodiment, the first connector 210 is provided with the fourth fixing hole 2122 opposite to the third fixing hole 124, so that the preformed fixing operation can be performed together in the connection operation of the first connector 210, thereby greatly saving the assembly period of the frame 100.

In one embodiment, referring to fig. 8, the second protrusion 412 is disposed opposite to the first slot 413. The second protrusion 412 is provided with a fifth fixing hole 4121, the fifth fixing hole 4121 penetrates through the bottom of the first clamping groove 413, and the first partition 125 is provided with a sixth fixing hole 1252 opposite to the fifth fixing hole 4121. As can be seen, when the first protrusion 411 is inserted into the first insertion hole 1251 and the first spacer 125 is snapped into the first clip groove 413, the fixing members respectively penetrate into the fifth fixing hole 4121 and the sixth fixing hole 1252, so that the first package 410 is stably connected to the side member 120.

Further, referring to fig. 8, a seventh fixing hole 134 opposite to the fifth fixing hole 4121 is further provided on the rear beam 130. After the rear cross member 130, the first package 410, and the side member 120 are preformed, the worker may insert the fixing members into the seventh fixing hole 134, the fifth fixing hole 4121, and the sixth fixing hole 1252, respectively, to complete the preforming operation between the rear cross member 130, the first package 410, and the side member 120. In particular, in the present embodiment, the eighth fixing hole 2132 opposite to the seventh fixing hole 134 is formed on the first connecting member 210, so that the preformed fixing operation can be performed together in the subsequent connecting operation, thereby greatly saving the assembling period of the frame 100. The fixing piece can be a bolt, a screw, a pin, a rivet or other fixing parts.

In one embodiment, referring to fig. 7, the first package 410 is further provided with a first end seal 420. The longitudinal beam 120 is provided with a first mounting seat 122. The rear cross member 130 is provided with a second mounting seat 131. The two side surfaces of the first end sealing member 420 are respectively sealed on the end of the first mounting seat 122 and the end of the second mounting seat 131. In this way, the first mounting seat 122 on the longitudinal beam 120 is tightly combined with the second mounting seat 131 of the rear cross beam 130 through the first end seal 420. The first mounting base 122 and the second mounting base 131 are both used for mounting the bottom plate structure 300. In the embodiment, structural adhesive is disposed between the first end seal 420 and the first mounting base 122, and between the first end seal 420 and the second mounting base 131.

In one embodiment, referring to fig. 8 and 9, a first positioning portion 421 and a second positioning portion 422 are respectively disposed on opposite sides of the first end seal 420, a third positioning portion 1221 that is in positioning fit with the first positioning portion 421 is disposed on the longitudinal beam 120, and a fourth positioning portion 1311 that is in positioning fit with the second positioning portion 422 is disposed on the rear cross beam 130. In this way, during the connection process of the first end seal 420, the first positioning portion 421 is first matched with the third positioning portion 1221, so that the first end seal 420 is positioned on the longitudinal beam 120; then, the second positioning portion 422 is matched with the fourth positioning portion 1311 in a positioning manner, so that the first mounting seat 122, the first end seal 420 and the second mounting seat 131 are effectively positioned, and the first mounting seat 122, the first end seal 420 and the second mounting seat 131 are more tightly combined.

Optionally, the first positioning portion 421 is a bump structure, and the third positioning portion 1221 is a groove structure; alternatively, the first positioning portion 421 is a groove structure, and the third positioning portion 1221 is a bump structure. Similarly, the second positioning portion 422 is a bump structure, and the fourth positioning portion 1311 is a groove structure; alternatively, the second positioning portion 422 is a groove structure, and the fourth positioning portion 1311 is a bump structure.

Further, referring to fig. 12, a third protrusion 431 and a fourth protrusion 432 are respectively disposed on opposite sides of the second package 430. The third protrusion 431 is configured to be inserted into a third receptacle 1271 on the stringer 120. The fourth projection 432 is for insertion into the fourth insertion hole 111 on the front cross member 110. It will be appreciated that during the connection process, the second package 430 is first inserted into the third receptacle 1271 by the third protrusion 431, such that the second package 430 is positioned on the stringer 120; next, the fourth protrusion 432 is inserted into the fourth insertion hole 111, so that the front beam 110, the second package 430 and the longitudinal beam 120 are all positioned, providing a stable frame structure for the subsequent connection operation of the second connection member 220, and facilitating the subsequent connection operation. Of course, in other embodiments, a jack structure may be disposed on the second package 430, and protruding structures may be disposed on the longitudinal beam 120 and the front cross beam 110, respectively, to achieve positioning among the second package 430, the front cross beam 110 and the longitudinal beam 120.

Specifically, the second package 430, the third protrusion 431 and the fourth protrusion 432 are integrally formed, so that the manufacturing process is greatly simplified and the production cycle is shortened. At the same time, the structural strength of the second package 430 is also advantageously improved.

Further, referring to fig. 12, a third partition 127 is disposed in the longitudinal beam 120, and the third partition 127 divides the longitudinal beam 120 into more than two third receptacles 1271. The third protrusions 431 are more than two, the more than two third protrusions 431 are arranged on the second pre-assembly 430 at intervals, a third clamping groove 433 is formed between two adjacent third protrusions 431 and the second pre-assembly 430, when the third protrusions 431 are inserted into the third insertion holes 1271, the third partition 127 is clamped into the third clamping groove 433, so that the longitudinal beam 120 and the second pre-assembly 430 are mutually interweaved and matched, and the binding force between the second pre-assembly 430 and the longitudinal beam 120 is greatly improved.

In one embodiment, referring to fig. 13, a fourth partition 112 is disposed in the front beam 110, and the fourth partition 112 divides the front beam 110 into more than two fourth insertion holes 111. The number of the fourth protrusions 432 is more than two, the more than two fourth protrusions 432 are arranged on the second pre-assembly 430 at intervals, a fourth clamping groove 434 is formed between two adjacent fourth protrusions 432 and the second pre-assembly 430, when the fourth protrusions 432 are inserted into the fourth insertion holes 111, the fourth separating member 112 is clamped into the fourth clamping groove 434, so that the front cross beam 110 and the second pre-assembly 430 are mutually interweaved and matched, and the binding force between the second pre-assembly 430 and the front cross beam 110 is greatly improved.

In one embodiment, referring to fig. 12 and 14, the connecting structure 200 of the frame further includes a second end seal 440, where the second end seal 440 is used for end sealing an end of the first mounting seat 122. In this way, the end of the first mount 122 is effectively sealed; at the same time, the pre-assembled longitudinal beam 120 and the front cross beam 110 are more compact. The second end seal 440 may be connected to the end of the first mounting base 122 by bonding, bolting, riveting or other means. In this embodiment, the second end seal 440 is connected to the end of the first mounting base 122 by a structural adhesive.

Alternatively, the second end seal 440 may be a separate component that is not connected to the second package 430; of course, in other embodiments, it may be integrally connected with the second package 430.

In one embodiment, referring to fig. 5 and 8, the first connecting member 210 includes a first fixing edge 212 and a second fixing edge 213 that are connected to each other, a first mounting hole 2121 is formed on the first fixing edge 212, a second mounting hole 123 opposite to the first mounting hole 2121 is formed on an outer side surface of the longitudinal beam 120, a third mounting hole 2131 is formed on the second fixing edge 213, and a fourth mounting hole 132 opposite to the third mounting hole 2131 is formed on an outer side surface of the rear cross beam 130. Therefore, during the assembly process of the frame 100, the longitudinal beam 120 is first matched with the rear cross beam 130, so that the longitudinal beam 120 and the rear cross beam 130 are well placed; the first fixing edge 212 is attached to the outer side surface of the longitudinal beam 120, and the second fixing edge 213 is attached to the outer side surface of the rear cross beam 130; next, the first and second mounting holes 2121 and 123, and the third and fourth mounting holes 2131 and 132 are respectively penetrated by the fixing members, so that the side member 120 and the rear cross member 130 are connected by the first connecting member 210. The connection operation between the side members 120 and the rear cross member 130 is completed.

The outer side of the side member 120, the outer side of the rear cross member 130, and the outer side of the front cross member 110 are all opposite to the accommodating chamber 140, and the side member 120, the rear cross member 130, and the front cross member 110 are sequentially connected to form the accommodating chamber 140, so that the side surface of the side member 120 facing away from the accommodating chamber 140 is the outer side surface of the side member 120, the side surface of the rear cross member 130 facing away from the accommodating chamber 140 is the outer side surface of the rear cross member 130, and the side surface of the front cross member 110 facing away from the accommodating chamber 140 is the outer side surface of the front cross member 110. In contrast, the side of the side member 120 facing the accommodating chamber 140 is the inner side of the side member 120, the side of the rear cross member 130 facing the accommodating chamber 140 is the inner side of the rear cross member 130, and the side of the front cross member 110 facing the accommodating chamber 140 is the inner side of the front cross member 110.

Further, referring to fig. 7, the first connector 210 further includes a first carrying edge 214. The first fixing edge 212 and the second fixing edge 213 are connected to the first carrying edge 214, and the first carrying edge 214 is used for carrying the longitudinal beam 120 and the rear cross beam 130. Therefore, when the first fixing edge 212 and the second fixing edge 213 act on the outer sides of the longitudinal beam 120 and the rear cross beam 130 respectively, the longitudinal beam 120 and the rear cross beam 130 are both supported on the first supporting edge 214, so that the longitudinal beam 120 and the rear cross beam 130 are stably aligned and matched in the connecting process, and the dislocation of the connecting position of the longitudinal beam 120 and the rear cross beam 130 caused by no stable support is avoided, thus greatly facilitating the assembly operation of operators, and being beneficial to improving the production efficiency of the lower shell.

In one embodiment, referring to fig. 6 and 7, the connection structure 200 further includes a third connection member 230. The third connecting member 230 includes a fifth fixed edge 232 and a sixth fixed edge 233 connected to each other. The fifth fixing edge 232 is provided with a fifth mounting hole 2321. The sixth mounting hole 126 is provided on the inner side of the side member 120 opposite to the fifth mounting hole 2321. The sixth fixing edge 233 is provided with a seventh mounting hole 2331. The rear cross member 130 has an eighth mounting hole 133 formed in an inner surface thereof, which is opposite to the seventh mounting hole 2331. It can be seen that the connection between the longitudinal beam 120 and the rear cross beam 130 in this embodiment adopts a double-layer connection manner, that is, the longitudinal beam 120 and the outer side surface of the rear cross beam 130 are connected by the first connector 210; the longitudinal beam 120 is then connected to the inner side of the rear cross beam 130 by a third connection 230. So for longeron 120 is connected more stably with rear cross beam 130, has promoted the bearing capacity on longeron 120 and the rear cross beam 130 greatly to make down casing overall structure intensity obtain effectively promoting, and then guarantee battery module's stability and security.

Further, referring to fig. 7, the connecting structure 200 of the frame further includes a first sealing member 211 and a second sealing member 231. The first seal 211 is for being disposed between the first connector 210 and the bezel 100. The second seal 231 is for being disposed between the third link 230 and the bezel 100. In this way, the first sealing element 211 and the second sealing element 231 respectively fill up the gap between the first connecting element 210 and the frame 100 and the gap between the third connecting element 230 and the frame 100, so that the inner side and the outer side of the frame 100 are effectively sealed, and the airtight performance of the frame 100 is effectively improved.

Specifically, the first sealing member 211 and the second sealing member 231 are both made of structural adhesive, and the structural adhesive is uniformly coated on the first connecting member 210 and the third connecting member 230 during the assembly process of the frame 100. Meanwhile, the structural adhesive is also beneficial to enhancing the binding force between the first connecting piece 210 and the frame 100, and between the third connecting piece 230 and the frame 100. In particular, in this embodiment, before the gluing, the first connecting piece 210, the third connecting piece 230, the rear cross member 130 and the longitudinal beam 120 are respectively anodized to increase the adhesion of the structural glue. The structural adhesive can be a single-component epoxy adhesive or a double-component epoxy adhesive, for example: BM1840C, BM 2090, and the like. The specific gluing process comprises the following steps: the loose oxide film on the surface of the workpiece is required to be polished; after polishing, coating structural adhesive, and curing by heating or room temperature; after curing, a baking process can be performed to make the structural adhesive more stable.

In one embodiment, referring to fig. 10, a third sealing member 221 is also disposed between the second connecting member 220 and the frame 100, so that a sealing engagement is achieved between the second connecting member 220 and the frame 100. In this embodiment, the third sealing member 221 is a structural adhesive, and before the adhesive is applied, the second connecting member 220, the front beam 110 and the longitudinal beam 120 are respectively anodized to increase the adhesive force of the structural adhesive.

In one embodiment, referring to fig. 11, the second connecting member 220 further includes a third fixing edge 222, a fourth fixing edge 223, and a second carrying edge 224. The third fixed edge 222 and the fourth fixed edge 223 are both connected to the second bearing edge 224. The second bearing edge 224 is used for bearing the longitudinal beam 120 and the front cross beam 110. Therefore, when the third fixing edge 222 and the fourth fixing edge 223 act on the outer sides of the longitudinal beam 120 and the front cross beam 110 respectively, the longitudinal beam 120 and the front cross beam 110 are both supported on the second supporting edge 224, so that the longitudinal beam 120 and the front cross beam 110 are stably aligned and matched in the connecting process, and the dislocation of the connecting position of the longitudinal beam 120 and the front cross beam 110 caused by no stable support is avoided.

In one embodiment, referring to fig. 1 and 15, the lower shell further includes a middle cross member 600, a middle longitudinal member 500, a first mounting member 510 and a second mounting member 520. The middle cross beam 600 is installed in the accommodating cavity 140, the middle cross beam 600 is installed on the frame 100, and two ends of the middle longitudinal beam 500 are respectively installed on the frame 100 and the middle cross beam 600 through the first installation piece 510 and the second installation piece 520. In this way, the middle rail 500 is stably mounted on the side frame 100 and the middle cross member 600 by the first and second mounting members 510 and 520.

Further, referring to fig. 16 and 17, the first mounting member 510 includes a first mounting portion 511, and a second mounting portion 512 disposed on the first mounting portion 511, wherein a first positioning groove 513 and a first connection hole 5114 communicating with the first positioning groove 513 are disposed on the first mounting portion 511, the first positioning groove 513 is clamped into one end of the middle longitudinal beam 500, a second connection hole 530 opposite to the first connection hole 5114 is disposed on the middle longitudinal beam 500, a third connection hole 5121 is disposed on the second mounting portion 512, and a fourth connection hole opposite to the third connection hole 5121 is disposed on the frame 100. As can be seen, during the installation of the middle rail 500, the first installation portion 511 is locked to one end of the middle rail 500 through the first positioning groove 513; the fixing member is inserted into the first connection hole 5114 and the second connection hole 530, so that the first mounting portion 511 is stably connected to the middle longitudinal beam 500; next, the second mounting portion 512 is fitted on the frame 100; the fixing piece penetrates into the third connecting hole 5121 and the fourth connecting hole, so that the second installation portion 512 is stably connected to the frame 100, and the installation structure of the middle longitudinal beam 500 is greatly convenient for the middle longitudinal beam 500 to be installed on the frame 100, so that professional operation personnel are not required, and the installation operation of the middle longitudinal beam 500 is simplified. Because be equipped with the second constant head tank 525 on the first installation department 511, consequently, in the installation, through the second constant head tank 525 for well longeron 500 obtains effective spacing, avoids well longeron 500 to take place to control not hard up in the use, so, makes well longeron 500 stably install on frame 100, thereby is favorable to promoting battery system's stability. The fixing piece can be a bolt, a screw, a pin, a rivet or other fixing parts.

Further, referring to fig. 16, the first mounting portion 511 includes a first top plate 5111, and a first side plate 5112 and a second side plate 5113 disposed on the first top plate 5111 at intervals. A first positioning groove 513 is defined between the first top plate 5111, the first side plate 5112 and the second side plate 5113, and at least one of the first top plate 5111, the first side plate 5112 and the second side plate 5113 is provided with a first connection hole 5114. In this way, the first mounting portion 511 is tightly fitted with the center sill 500. In particular, in the present embodiment, the first top plate 5111, the first side plate 5112, the second side plate 5113, and the second mounting portion 512 are integrally formed, which is beneficial to simplifying the manufacturing process of the mounting structure of the middle longitudinal beam 500 and improving the strength of the mounting structure of the middle longitudinal beam 500.

In one embodiment, referring to fig. 18 and 19, the second mounting member 520 is provided with a fifth connecting hole 5211 and a sixth connecting hole 5212 at intervals. The fifth coupling hole 5211 is provided to be opposite to the seventh coupling hole 540 of the center sill 500. The sixth coupling hole 5212 is provided opposite to the eighth coupling hole of the middle rail 600. As can be seen, the fixing members are respectively inserted into the fifth and seventh coupling holes 5211 and 540, so that the second mounting member 520 is coupled to the center rail 500; the fixing members are then inserted into the sixth and eighth coupling holes 5212 and eighth coupling holes, respectively, so that the second mounting member 520 is coupled to the middle cross member 600.

Further, referring to fig. 18, a second positioning groove 525 is provided on the second mounting member 520. The sixth connection hole 5212 communicates with the second positioning groove 525, and the second positioning groove 525 is configured to be snapped into the middle cross member 600. In this way, the second positioning groove 525 makes the connection between the second mounting member 520 and the middle cross member 600 tighter, so that the middle longitudinal member 500 is more stable in the lower case, thereby further improving the stability of the battery system.

Still further, referring to fig. 18, a third positioning groove 526 is further provided on the second mounting member 520 and is in communication with the second positioning groove 525. The fifth connection hole 5211 communicates with the third positioning groove 526. The third positioning groove 526 is used to be snapped into the other end of the center rail 500. As can be seen, the second mounting member 520 is engaged with the center rail 500 through the third positioning groove 526; the fixing members are then inserted into the fifth and seventh connection holes 5211 and 540, respectively, so that the second mounting member 520 is more stably connected to the middle rail 500.

In one embodiment, referring to fig. 18, the second mounting member 520 includes a second top plate 521, a third side plate 522, a fourth side plate 523 and a fifth side plate 524. The third side plate 522 is disposed on opposite sides of the second top plate 521 spaced apart from the fourth side plate 523. The fifth side plate 524 is disposed at one end of the second top plate 521, and a second positioning groove 525 is defined between an end of the third side plate 522, an end of the fourth side plate 523, and side surfaces of the second top plate 521 and the fifth side plate 524, and a third positioning groove 526 is defined between a side surface of the third side plate 522, a side surface of the fourth side plate 523, and the second top plate 521. In this way, the structure of the second mounting member 520 is skillfully designed in this embodiment, and the third side plate 522, the fourth side plate 523, the second top plate 521 and the fifth side plate 524 are mutually matched to form the second positioning groove 525 and the third positioning groove 526, so that the second mounting member 520 is stably mounted on the middle longitudinal beam 500 and the middle cross beam 600.

In one embodiment, referring to fig. 1, 2 and 3, the chassis structure 300 includes a first chassis 310, a second chassis 320, a first connecting edge 312 and a second connecting edge 322. One end of the second bottom plate 320 is opposite to one end of the first bottom plate 310. The first base plate 310 and the second base plate 320 are respectively provided with a first mounting surface 311 and a second mounting surface 321. The first connecting edge 312 is disposed on the first base plate 310. The second connecting edge 322 is disposed on the second bottom plate 320. When the first base plate 310 is matched with the second base plate 320, the first connecting edge 312 is connected to the second mounting surface 321 in a sealing manner, and the second connecting edge 322 is connected to the first mounting surface 311 in a sealing manner. It can be seen that during the splicing process, the end of the first bottom plate 310 is first matched with the end of the second bottom plate 320; the first connecting edge 312 is then contacted with the second mounting surface 321, and the second connecting edge 322 is contacted with the first mounting surface 311; finally, the first connecting edge 312 is in sealing connection with the second mounting surface 321, and the second connecting edge 322 is in sealing connection with the first mounting surface 311, so that double-layer sealing connection is realized between the first bottom plate 310 and the second bottom plate 320, the bonding force between the first bottom plate 310 and the second bottom plate 320 is improved, the strength of the bottom plate structure 300 is enhanced, the sealing performance between the first bottom plate 310 and the second bottom plate 320 is also greatly improved, and the air tightness failure of the lower shell caused by cracking or breakage of one layer of the connecting structure 200 is effectively avoided.

It should be noted that, the sealing connection in this embodiment is understood to be a connection between the first connecting edge 312 and the first mounting surface 311 or a connection between the second connecting edge 322 and the second mounting surface 321, and a corresponding sealing operation is performed. Meanwhile, the opposite matching of the end of the second bottom plate 320 and the end of the first bottom plate 310 in this embodiment should be understood that during the splicing process, the end of the second bottom plate 320 and the end of the first bottom plate 310 are matched and can be anastomosed together.

Alternatively, the sealing connection may be achieved by bonding, welding, bolting and adding a seal, press fit and bolting or otherwise. Wherein the seal may be a sealant, gasket or other seal. When the sealing connection is solely bolted, the bolts are tightened to achieve a close fitting state between the connecting edge and the mounting surface or between the mounting surface and the mounting surface, so that a certain sealing effect can be achieved.

Further, referring to fig. 3, 20, 21 and 22, a first adhesive groove 3111 is formed on the first connecting edge 312 or the second mounting surface 321; or the first connecting edge 312 and the second mounting surface 321 are respectively provided with a first glue groove 3111. The first glue tank 3111 is used for filling glue. In this way, the first connecting edge 312 is stably mounted on the second mounting surface 321 by the glue. Meanwhile, in this embodiment, the first connecting edge 312 is bonded to the second mounting surface 321 by glue, so that the splicing process of the bottom plate structure 300 realizes a welding-free operation, and the structural stability of the lower housing is greatly improved. Wherein, the glue can be structural glue.

In one embodiment, referring to fig. 3 and 22, the second adhesive groove 3121 is provided on the second connecting edge 322 and/or the first mounting surface 311. The second glue well 3121 is for filling glue. In this way, the second connecting edge 322 is stably mounted on the first mounting surface 311 by the glue. Meanwhile, the welding-free operation is realized in the splicing process of the bottom plate structure 300, and the structural stability of the lower shell is greatly improved. Wherein, the glue can be structural glue.

In one embodiment, referring to fig. 23, the first bottom plate 310 is further provided with a third mounting surface 313 and a third connecting edge 314, the frame 100 is provided with a fourth mounting surface 150 and a fifth mounting surface 160, the third mounting surface 313 is connected to the fourth mounting surface 150 in a sealing manner, and the third connecting edge 314 is connected to the fifth mounting surface 160 in a sealing manner. In this embodiment, the third mounting surface 313 is in sealing connection with the fourth mounting surface 150, and the third connecting edge 314 is in sealing connection with the fifth mounting surface 160, so as to realize double-layer sealing connection, and thus, the sealing performance between the first bottom plate 310 and the frame 100 is greatly improved, and the air sealing performance of the lower housing is further improved.

Specifically, referring to fig. 23, the third connecting edge 314 and the third mounting surface 313 have a height difference on the first bottom plate 310. Meanwhile, the fourth mounting surface 150 and the fifth mounting surface 160 have a height difference on the bezel 100. In this way, the first chassis 310 is more tightly coupled with the bezel 100.

In one embodiment, referring to fig. 23, a third glue groove 151 is provided on the third mounting surface 313 and/or the fourth mounting surface 150, and the third glue groove 151 is used for filling glue. Meanwhile, a fourth glue groove 161 is provided on the third connecting edge 314 and/or the fifth mounting surface 160, and the fourth glue groove 161 is used for filling glue. Therefore, the welding is reduced, and the lower shell is favorable for realizing the non-welding process production.

In one embodiment, referring to fig. 20, 21 and 24, a sixth mounting surface 323 and a fourth connecting edge 324 are provided on the second bottom plate 320, a seventh mounting surface 550 and an eighth mounting surface 560 are provided on the middle rail 500, the sixth mounting surface 323 is sealingly connected to the seventh mounting surface 550, and the fourth connecting edge 324 is sealingly connected to the eighth mounting surface 560. In this way, in this embodiment, the sixth mounting surface 323 and the seventh mounting surface 550 are respectively connected in a sealed manner, and the fourth connecting edge 324 and the eighth mounting surface 560 are connected in a sealed manner, so that a two-layer sealed connection is achieved.

Specifically, the fourth connecting side 324 and the sixth mounting side 323 have a height difference on the second bottom plate 320. Meanwhile, the seventh mounting surface 550 and the eighth mounting surface 560 also have a height difference on the center sill 500. In this way, the second bottom plate 320 is more tightly coupled to the center sill 500.

In one embodiment, referring to fig. 24, a fifth glue groove 551 is provided on the sixth mounting surface 323 and/or the seventh mounting surface 550, and the fifth glue groove 551 is used for filling glue. Meanwhile, a sixth glue groove 561 is provided on the fourth connecting edge 324 and/or the eighth mounting surface 560, and the sixth glue groove 561 is used for filling glue.

In one embodiment, referring to fig. 7 and 12, the longitudinal beam 120 is provided with an introduction assembly 121, the introduction assembly 121 is provided with an introduction channel 1213, and the introduction channel 1213 is used to introduce the rear cross beam 130 or the front cross beam 110, and make the rear cross beam 130 or the front cross beam 110 cooperate with the longitudinal beam 120. In the alignment and matching process of the rear cross beam 130 or the front cross beam 110 and the longitudinal beam 120, the rear cross beam 130 or the longitudinal beam 120 is led into the guide channel 1213 through the guide-in assembly 121, so that the rear cross beam 130 or the longitudinal beam 120 moves according to a preset track, and the rear cross beam 130 or the front cross beam 110 is matched with the longitudinal beam 120, and thus, operators are not required to debug the rear cross beam 130 or the front cross beam 110 back and forth, the alignment and matching operation between the rear cross beam 130 or the front cross beam 110 and the longitudinal beam 120 is greatly facilitated, the assembly efficiency of the frame 100 is improved, and the production efficiency of a lower shell is improved.

Further, referring to fig. 7, the introducing assembly 121 includes a first introducing member 1211 and a second introducing member 1212. The second lead-in 1212 is connected to the stringer 120 through the first lead-in 1211. The stringers 120, the first lead-in 1211 and the second lead-in 1212 enclose a lead-in channel 1213. It can be seen that the introduction assembly 121 has a structure of "L" or approximately "L", and introduces the rear cross member 130 or the front cross member 110 into the introduction channel 1213 during the alignment and matching, so that the rear cross member 130 or the front cross member 110 moves along a predetermined track, and the longitudinal member 120 is accurately matched with the rear cross member 130 or the front cross member 110.

In one embodiment, please refer to fig. 1, 2, 4, 7 and 12, a battery pack includes an upper housing and a lower housing in any of the above embodiments. The upper shell covers the lower shell.

The battery pack adopts the lower case, and during the manufacturing process, the ends of the two longitudinal beams 120 are respectively positioned on the two ends of the rear cross beam 130 through the first package 410; the second package 430 is then used to position the two ends of the front cross member 110 at the ends of the two stringers 120, respectively, so that the pre-forming operation of the frame 100 is completed. Then, the longitudinal beam 120 and the rear cross beam 130 are stably connected through the first connector 210; the side members 120 are stably connected with the front cross member 110 by the second connection members 220 to form a stable frame 100; finally, the bottom plate structure 300 is installed in the rim 100 to obtain the lower housing. Because the preassembly structure 400 is adopted in the embodiment, the rear cross beam 130 or the front cross beam 110 is stably aligned on the longitudinal beam 120, so that the assistance of supporting by multiple persons is not needed in the manufacturing process, the labor force is greatly liberated, the assembling process of the frame 100 is time-saving and labor-saving, and the production efficiency of the lower shell is improved. Meanwhile, due to the adoption of the preassembled structure 400, manual supporting operation is replaced, dislocation or offset between the structures due to hand shake in the assembling process of the frame 100 is effectively avoided, the assembling process of the frame 100 is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, the connecting structure 200 of the frame is adopted to replace the traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few welding or no welding process machine, and the production efficiency of the lower shell is improved.

In one embodiment, please refer to fig. 1, 2, 4, 7, 12 and 25, a method for manufacturing a lower housing includes the following steps:

s10, positioning the end parts of the two longitudinal beams 120 on the two ends of the rear cross beam 130 through the first preassembly 410;

s20, positioning two ends of the front cross beam 110 at the end parts of the two longitudinal beams 120 respectively through the second preassembly 430 to complete the preforming operation;

s30, after preforming, connecting the first connecting pieces 210 between the longitudinal beams 120 and the rear cross beams 130 respectively, so that the two longitudinal beams 120 are connected with the rear cross beams 130 respectively;

s40, respectively connecting the second connecting pieces 220 between the longitudinal beams 120 and the front cross beam 110, so that the two longitudinal beams 120 are respectively connected with the front cross beam 110 to obtain a frame 100;

s50, after the frame 100 is obtained, the bottom plate structure 300 is installed in the frame 100.

In the lower case manufacturing method, during the manufacturing process, the ends of the two stringers 120 are positioned on the two ends of the rear cross member 130 through the first package 410; the second package 430 is then used to position the two ends of the front cross member 110 at the ends of the two stringers 120, respectively, so that the pre-forming operation of the frame 100 is completed. Then, the longitudinal beam 120 and the rear cross beam 130 are stably connected through the first connector 210; the side members 120 are stably connected with the front cross member 110 by the second connection members 220 to form a stable frame 100; finally, the bottom plate structure 300 is installed in the rim 100 to obtain the lower housing. Because the preassembly structure 400 is adopted in the embodiment, the rear cross beam 130 or the front cross beam 110 is stably aligned on the longitudinal beam 120, so that the assistance of supporting by multiple persons is not needed in the manufacturing process, the labor force is greatly liberated, the assembling process of the frame 100 is time-saving and labor-saving, and the production efficiency of the lower shell is improved. Meanwhile, due to the adoption of the preassembled structure 400, manual supporting operation is replaced, dislocation or offset between the structures due to hand shake in the assembling process of the frame 100 is effectively avoided, the assembling process of the frame 100 is stably carried out, and the structural accuracy of the lower shell is greatly improved. In addition, in the manufacturing process, the connecting structure 200 of the frame is adopted to replace the traditional welding mode, so that the manufacturing process is simplified, the lower shell is produced by a few welding or no welding process machine, and the production efficiency of the lower shell is improved.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims

1. A lower housing, comprising:

the frame comprises a front cross beam, a longitudinal beam and a rear cross beam, wherein two ends of the front cross beam are respectively matched with two ends of the rear cross beam through the longitudinal beam, and an accommodating cavity is formed by enclosing the front cross beam and the rear cross beam;

the preassembly structure comprises a first preassembly component and a second preassembly component, wherein the first preassembly component is positioned between the end part of the longitudinal beam and the end part of the rear transverse beam, the second preassembly component is positioned between the end part of the longitudinal beam and the end part of the front transverse beam, a first bulge and a second bulge are respectively arranged on two opposite sides of the first preassembly component, a first jack matched with the first bulge in a positioning manner is arranged on the longitudinal beam, and a second jack matched with the second bulge in a positioning manner is arranged on the rear transverse beam;

The connecting structure comprises a first connecting piece and a second connecting piece, the first connecting piece is connected between the longitudinal beam and the rear cross beam, and the second connecting piece is connected between the longitudinal beam and the front cross beam;

the first bulges are more than two, the more than two first bulges are arranged on the first pre-assembly at intervals, a first clamping groove is formed between two adjacent first bulges and the first pre-assembly, a first separating piece is arranged in the longitudinal beam and divides the longitudinal beam into more than two first jacks, and when the first bulges are inserted into the first jacks, the first separating piece is clamped into the first clamping groove; the second bulge is arranged opposite to the first clamping groove, a fifth fixing hole is formed in the second bulge, the fifth fixing hole penetrates through the bottom of the first clamping groove, and a sixth fixing hole opposite to the fifth fixing hole is formed in the first partition piece; the second bulges are more than two, the more than two second bulges are arranged on the first pre-assembly at intervals, a second clamping groove is formed between two adjacent second bulges and the first pre-assembly, a second partition piece is arranged in the rear cross beam and divides the rear cross beam into more than two second jacks, and when the second bulges are inserted into the second jacks, the second partition piece is clamped into the second clamping groove; the first bulge is arranged opposite to the second clamping groove, a first fixing hole is formed in the first bulge, the first fixing hole penetrates through the bottom of the second clamping groove, and a second fixing hole opposite to the first fixing hole is formed in the second partition piece; the first preassembly is also provided with a first end sealing piece, the longitudinal beam is provided with a first mounting seat, the rear cross beam is provided with a second mounting seat, and two side surfaces of the first end sealing piece are respectively sealed on the end parts of the first mounting seat and the second mounting seat; and

And the bottom plate structure is arranged in the accommodating cavity and is connected with the frame.

2. The lower housing of claim 1, wherein the first connector includes a first fixed edge and a second fixed edge that are connected to each other, the first fixed edge is provided with a first mounting hole, the outer side of the longitudinal beam is provided with a second mounting hole opposite to the first mounting hole, the second fixed edge is provided with a third mounting hole, and the outer side of the rear cross beam is provided with a fourth mounting hole opposite to the third mounting hole.

3. The lower housing of claim 2, wherein the connecting structure further comprises a third connecting member, the third connecting member comprises a fifth fixing edge and a sixth fixing edge which are connected with each other, a fifth mounting hole is formed in the fifth fixing edge, a sixth mounting hole opposite to the fifth mounting hole is formed in the inner side surface of the longitudinal beam, a seventh mounting hole is formed in the sixth fixing edge, and an eighth mounting hole opposite to the seventh mounting hole is formed in the inner side surface of the rear cross beam.

4. The lower housing of claim 1, further comprising a middle cross member, a middle longitudinal member, a first mounting member and a second mounting member, wherein the middle cross member is installed in the accommodating cavity, the middle cross member is installed on the frame, and two ends of the middle longitudinal member are installed on the frame and the middle cross member respectively through the first mounting member and the second mounting member.

5. The lower housing according to claim 4, wherein the first mounting member includes a first mounting portion and a second mounting portion disposed on the first mounting portion, a first clamping groove and a first connecting hole communicated with the first clamping groove are disposed on the first mounting portion, the first clamping groove is clamped into one end of the middle longitudinal beam, a second connecting hole opposite to the first connecting hole is disposed on the middle longitudinal beam, a third connecting hole is disposed on the second mounting portion, and a fourth connecting hole opposite to the third connecting hole is disposed on the frame.

6. The lower housing of any one of claims 1-5, wherein the floor structure comprises a first floor, a second floor, a first connecting edge, and a second connecting edge, wherein one end of the second floor is in opposite engagement with one end of the first floor, the first floor and the second floor are respectively provided with a first mounting surface and a second mounting surface, the first connecting edge is disposed on the first floor, the second connecting edge is disposed on the second floor, and when the first floor and the second floor are engaged, the first connecting edge is in sealing connection with the second mounting surface, and the second connecting edge is in sealing connection with the first mounting surface.

7. A battery pack comprising an upper case and the lower case of any one of claims 1 to 6, the upper case being covered on the lower case.

8. A method of manufacturing a lower shell for use in preparing a lower shell according to any one of claims 1 to 6, comprising the steps of:

positioning the ends of the two longitudinal beams on the two ends of the rear cross beam respectively through a first pre-assembly;

positioning two ends of the front cross beam at the end parts of the two longitudinal beams respectively through a second pre-assembly to finish the pre-forming operation;

after preforming, connecting first connecting pieces between the longitudinal beams and the rear cross beams respectively, so that the two longitudinal beams are connected with the rear cross beams respectively;

connecting second connecting pieces between the longitudinal beams and the front cross beam respectively, so that the two longitudinal beams are connected with the front cross beam respectively to obtain a frame;

after the frame is obtained, the bottom plate structure is arranged in the frame.