CN113782877A

CN113782877A - Battery pack and electric vehicle

Info

Publication number: CN113782877A
Application number: CN202010442984.4A
Authority: CN
Inventors: 王晓鹏; 彭青波; 鲁志佩; 朱建华; 朱燕
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2020-05-22
Filing date: 2020-05-22
Publication date: 2021-12-10

Abstract

The invention provides a battery pack, which comprises a box body, an explosion-proof structure and a plurality of pole core strings which are positioned in the box body and are electrically connected with each other; the box body comprises at least one sub-box body, a structural beam is arranged in the sub-box body, the structural beam divides the inner part of the corresponding sub-box body into a plurality of containing cavities, and pole core strings are arranged in the containing cavities; the box body is provided with a through hole, the accommodating cavity is communicated with the through hole, and the explosion-proof structure corresponds to the sealing through hole; the box body is provided with a mounting part which is used for being connected and fixed with an external load. The invention further provides an electric vehicle. The battery pack is provided with the explosion-proof structure at the position of the box body corresponding to the containing cavity, so that the battery pack can be prevented from exploding due to abnormal work and severe gas production of the pole core string in the containing cavity.

Description

Battery pack and electric vehicle

Technical Field

The invention relates to the technical field of batteries, in particular to a battery pack and an electric vehicle.

Background

With the continuous popularization of new energy automobiles, the use requirement of power batteries in the new energy automobiles becomes higher and higher. The design of traditional battery package box usually includes the tray and the upper cover of being connected with the tray, and the tray is formed with the bottom plate assembly welding by the frame construction that a plurality of boundary beams are constituteed to at some strengthening cross beams of tray internal design, longeron structure, battery module fixes on the bottom plate, and battery box structure is more complicated, manufacturing cost is high, and the commonality between the different projects is poor, is difficult for standardization, modularization, the mass production manufacturing of battery package box. Moreover, when the conventional battery pack is assembled, a plurality of single batteries are generally arranged in sequence to form a battery pack, then end plates are arranged at two ends of the battery pack in the length direction, side plates are arranged at two sides of the battery pack in the width direction, and the end plates and the side plates are fixedly connected through bolts or pull rods or welding to form a battery module; and finally, mounting the battery module in the tray through fasteners such as bolts and the like. Due to the fact that structural members such as end plates and side plates are additionally arranged in the assembling mode, the battery pack is large in weight and low in space utilization rate, light weight design of the electric vehicle is not facilitated, and the requirement for high cruising ability of the electric vehicle cannot be met.

In addition, the box of the conventional battery pack is usually a sealed box, and when the single battery contained in the box generates gas violently due to abnormal operation, the gas pressure may cause explosion of the battery pack, thereby affecting the safety of the battery pack.

Disclosure of Invention

The present disclosure is directed to solving at least one of the problems in the prior art. To this end, in a first aspect of the present application, there is provided a battery pack including a case, an explosion-proof structure, and a plurality of pole core strings electrically connected to each other in the case;

the box body comprises a box body, the box body comprises at least one sub-box body, a structural beam is arranged in at least one sub-box body, the structural beam divides the inner part of the corresponding sub-box body into a plurality of containing cavities, and the pole core string is arranged in at least one containing cavity;

the pole core string comprises a plurality of pole core groups which are arranged along a first direction and are connected in series, the pole core groups are packaged in a packaging film, the length of the pole core string extends along the first direction, and the first direction is the length direction of the box body or the width direction of the box body;

the box body is provided with a through hole, the accommodating cavity is communicated with the through hole, and the explosion-proof structure correspondingly seals the through hole; the box body is provided with an installation part, and the installation part is used for being connected and fixed with an external load.

In a second aspect of the present application, there is provided an electric vehicle including a vehicle body and a battery pack as described above, the battery pack being fixed to the vehicle body through the mounting portion.

The invention has the beneficial effects that: the battery pack is provided with the explosion-proof structure at the position of the box body corresponding to the accommodating cavity, so that the battery pack can be prevented from exploding due to abnormal work and severe gas production of the pole core string in the accommodating cavity, and the use safety of the battery pack is improved; moreover, the box body comprises at least one sub-box body, so that the number of the sub-box bodies can be selected according to actual needs, the universality of the design of the battery pack can be increased, and the standardized and modularized production and manufacturing of the battery pack are facilitated. In addition, the plurality of pole core groups are arranged in the box body of the battery pack, so that the pole cores are not required to be assembled into the battery shell to be assembled into the single battery, then the single battery, the end plates, the side plates and the like are assembled into the battery module, and then the battery module is assembled onto the box body of the battery pack. Moreover, the battery pack omits structural members such as end plates and side plates for forming the battery module, and is beneficial to reducing the weight of the battery pack and improving the space utilization rate of the battery pack, so that the lightweight design of the electric vehicle can be realized, and the requirement of the electric vehicle for higher cruising ability can be met.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 is a schematic perspective view of a box according to an embodiment of the present invention.

Fig. 2 is a schematic perspective view of a case separated from an explosion-proof structure according to an embodiment of the present invention.

Fig. 3 is a schematic perspective view of an explosion-proof structure according to an embodiment of the present invention.

Fig. 4 is a partially enlarged view of a portion M in fig. 3.

Fig. 5 is a schematic perspective view of a pole piece string placed in one of the accommodating cavities in the box according to an embodiment of the present invention.

Fig. 6 is a schematic perspective view of a structure of the case provided by an embodiment of the invention, in which all the accommodating cavities are used for accommodating the pole piece strings.

Fig. 7 is a schematic perspective view illustrating an insulating support installed on a box according to an embodiment of the present invention.

Fig. 8 is a schematic perspective view of an end plate separated from a box according to an embodiment of the present invention.

Fig. 9 is an exploded perspective view of a case having three sub-cases according to an embodiment of the present invention.

Fig. 10 is an exploded perspective view of a case having two sub-cases according to an embodiment of the present invention.

Fig. 11 is an exploded perspective view of a case having a sub-case according to an embodiment of the present invention.

Fig. 12 is a schematic structural view illustrating an end sub-box integrally formed with a first side rail according to an embodiment of the present invention.

Fig. 13 is a schematic structural diagram of two pole core strings connected in series in the same accommodating cavity according to an embodiment of the present invention.

Fig. 14 is a schematic structural diagram of two pole core strings connected in series in the same accommodating cavity according to another embodiment of the present invention.

Fig. 15 is a schematic structural diagram of two pole cores connected in series and in parallel in the same accommodating cavity according to an embodiment of the present invention.

Fig. 16 is a schematic structural diagram of two pole core strings connected in series in two accommodating cavities according to an embodiment of the present invention.

Fig. 17 is a schematic structural diagram of two pole core strings connected in series in two accommodating cavities according to another embodiment of the present invention.

Fig. 18 is a schematic structural diagram of two pole cores in series-parallel connection in two accommodating cavities according to an embodiment of the present invention.

Fig. 19 is a schematic structural diagram of an encapsulation film encapsulating a pole-core group according to an embodiment of the invention.

Fig. 20 is a schematic structural view of an encapsulating film encapsulating a pole-core group according to another embodiment of the invention.

Detailed Description

While the following is a description of the preferred embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present 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 one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined 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; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Referring to fig. 1, 2 and 5, the present invention provides a battery pack 10, which includes a case 100, an explosion-proof structure 200 (shown in fig. 2), and a plurality of pole core strings 600 (shown in fig. 5) electrically connected to each other and located in the case 100. The case 100 in this application is a sealed case.

The box body 100 comprises a box body 110, the box body 110 comprises at least one sub-box body 120, a structural beam 400 is arranged in the at least one sub-box body 120, the structural beam 400 divides the inside of the corresponding sub-box body 120 into a plurality of accommodating cavities 500, and a pole core string 600 is arranged in at least one accommodating cavity 500. The pole core string 600 includes a plurality of pole core groups 610 (shown in fig. 5) arranged in series along a first direction X, the pole core groups 610 are encapsulated in an encapsulation film 700 (shown in fig. 19 and 20), a length of the pole core string 600 extends along the first direction X, and the first direction X is a length direction of the case 100 or a width direction of the case 100.

The number of the sub-boxes 120 may be one (as shown in fig. 11), or may be multiple, for example, 2 (as shown in fig. 10), or 3 (as shown in fig. 1 and 9). When there is one sub-box 120 (as shown in fig. 11), the sub-box 120 is the box 100 itself, and the interior of the box 100 is divided into a plurality of accommodating cavities 500 by the structural beam 400, and the number of the accommodating cavities 500 may be set arbitrarily, for example, 8. When there are a plurality of sub-cases 120, for example, 3 sub-cases, two adjacent sub-cases 120 may be connected and fixed by welding, or may be connected and fixed by a detachable structure, referring to fig. 9, two adjacent sub-cases 120 may be connected and fixed by a connecting plate 300, which may be detachable or non-detachable. Wherein the structural beams 400 are also used to support the tank 100, further improving the structural strength of the tank 100.

In this application, one pole piece string 600 or a plurality of pole piece strings 600 may be disposed in each accommodation cavity 500, and when a plurality of pole piece strings 600 are disposed, the plurality of pole piece strings 600 may be connected in series or in parallel. Wherein each pole-core string 600 may include a plurality of pole-core sets 610, for example, including 5 pole-core sets 610 connected in series. The number of pole core strings 600 in each accommodating cavity 500 and the number of pole core groups 610 in each pole core string 600 can be set according to the actual needs of products.

The box body 100 is provided with a through hole 130, the accommodating cavity 500 is communicated with the through hole 130, and the explosion-proof structure 200 is corresponding to the through hole 130; the housing 100 is provided with a mounting portion 140, and the mounting portion 140 is used for connection and fixation with an external load. In some embodiments, each receiving cavity 500 is in communication with at least one through hole 130. In some embodiments, two or more through holes 130 may be provided in each accommodating chamber 500. In other embodiments, one accommodating chamber 500 of the accommodating chambers 500 is in communication with at least one through hole 130, and the accommodating chamber 500 is in communication with the other accommodating chambers 500. Holes for communicating 130 the adjacent two receiving cavities 500 may be provided on the structural beam 400; or two adjacent accommodating chambers 500 communicate through openings at both ends of the accommodating chamber 500.

Wherein the box 100 is provided with a through hole 130, including the through hole 130 provided on each sub-box 120 corresponding to each accommodation chamber 500. The explosion-proof structure 200 is disposed at a position of the case 100 corresponding to the accommodating cavity 500, so as to prevent the electrode core string 600 in the accommodating cavity 500 from exploding due to abnormal operation and severe gas generation, thereby improving the safety of the battery pack. The explosion proof structure 200 may also seal the through-hole 130 when the battery pack is normally operated, that is, the explosion proof structure 200 may function as a sealing cover.

The battery pack 10 of the present application has the mounting part 140 directly for mounting on an external load, for example, on an electric vehicle, wherein the mounting part 140 may be formed simultaneously with the process of integrally molding the case 100, or may be formed by drilling or the like after the case 100 is molded. In other embodiments, the mounting portion 140 may also be a hanging ring or a mounting block, and the mounting portion 140 may be connected and fixed with an external load by bolting, riveting, welding, or the like, for example, a vehicle body.

It should be noted that the case 100 of the battery pack is detachably or non-detachably connected and fixed to an external load (for example, a body of an electric vehicle) via the mounting portion 140 provided thereon. The case 100 of the battery pack of the present application cannot be simply understood as a case of a battery module or a unit cell. Generally, the battery pack further includes at least one of a Battery Management System (BMS), a battery connector, a battery sampler, and a battery thermal management system.

The battery pack 10 is provided with the explosion-proof structure 200 at the position of the box body 100 corresponding to the accommodating cavity 500, so that the battery pack can be prevented from being exploded due to abnormal work and severe gas production of the pole core string 600 positioned in the accommodating cavity 500, and the use safety of the battery pack can be improved; moreover, the case body 110 includes at least one sub-case body 120, so that the number of the sub-case bodies 120 can be selected according to actual needs, thereby increasing the versatility of the design of the battery pack and facilitating the standardized and modular production and manufacture of the battery pack. In addition, in the invention, the plurality of pole core groups 610 are arranged in the box body 100 of the battery pack, so that the pole core groups 610 are not required to be firstly arranged in the battery shell to be assembled into the single battery, then the single battery, the end plates, the side plates and the like are assembled into the battery module, and then the battery module is assembled on the battery pack box body. Moreover, the battery pack omits structural members such as end plates and side plates for forming the battery module, and is beneficial to reducing the weight of the battery pack and improving the space utilization rate of the battery pack, so that the lightweight design of the electric vehicle can be realized, and the requirement of the electric vehicle for higher cruising ability can be met.

According to the invention, the pole core groups 610 are packaged in the packaging film, the pole core groups 610 are connected in series to form the pole core string 600, and the pole core string 600 is arranged in the box body 100 of the battery pack 10, so that double-layer sealing is realized through the packaging film and the box body 100 of the battery pack, and the sealing effect is improved.

In the present invention, the pole piece group 610 includes at least one pole piece. When the pole piece group 610 includes two or more pole pieces, the pole pieces are connected in parallel.

The pole core mentioned in the present invention is a pole core commonly used in the field of power batteries, and the pole core group 610 belong to the constituent parts of the battery and cannot be understood as the battery itself; in addition, the pole core can be formed by winding or can be made in a lamination mode; generally, the pole core includes at least a positive pole piece, a separator, and a negative pole piece.

Referring again to fig. 1, in a further embodiment, the sub-tank 120 includes a top plate 121 and a bottom plate 122 oppositely disposed along a second direction Y, the second direction Y is a height direction of the tank 100, the structural beam 400 is located between the top plate 121 and the bottom plate 122, and at least one structural beam 400 is connected to the top plate 121 and the bottom plate 122. The design enables the structural beam 400, the top plate 121 and the bottom plate 122 to form an I-shaped structure, and the structure has high strength and rigidity, so that the box body of the battery pack has good performances of bearing, impact resistance, extrusion resistance and the like. When installing this kind of battery package on whole car, the structural strength of this battery package can regard as a part of whole car structural strength to can promote the structural strength of whole car, be favorable to realizing the light-weighted design requirement of whole car of electric automobile, also reduce the design and the manufacturing cost of whole car simultaneously.

Wherein, the structural beam 400 is connected to the top plate 121 and the bottom plate 122, it can be understood that the structural beam 400 is integrally formed with the top plate 121 and the bottom plate 122; alternatively, the structural beam 400, the top plate 121, and the bottom plate 122 may be separately formed and then connected by a direct or indirect connection, which is not particularly limited in the present application. The direct connection may be that one end of the structural beam 400 is connected to the bottom plate 122, the opposite end of the structural beam 400 is connected to the top plate 121, and the indirect connection may be that one end of the structural beam 400 is connected to the bottom plate 122 through an intermediate plate, and the opposite end of the structural beam 400 is connected to the top plate 121 through an intermediate plate.

In some embodiments, at least one structural beam 400 is joined to the top plate 121 and the bottom plate 122. It can be understood that the top plate 121, the bottom plate 122 and the structural beam 400 are integrally formed; or, one of the top plate 121 and the bottom plate 122 is integrally formed with the structural beam 400, and the other is welded to the structural beam 400; alternatively, one end of the structural beam 400 is welded to the bottom plate 122 and the opposite end of the structural beam 400 is welded to the top plate 121. Alternatively, one end of the structural beam 400 is welded to the bottom plate 122 and the opposite end of the structural beam 400 is welded to the top plate 121.

In a further embodiment, the through hole 130 is a glue injection hole 131. For injecting structural adhesive into the receiving cavity 500. That is, in the present embodiment, the through hole 130 is an air outlet and is also a glue injection hole. After the pole core cluster 600 is installed in the box 100, structural glue is injected into the accommodating cavity 500 through the through hole 130, the pole core cluster 600 is fixed in the accommodating cavity 500, and the pole core cluster 600 is prevented from shaking in the accommodating cavity 500. After the structural adhesive is injected, the through hole 130 can be used as an air outlet for exhausting air in the accommodating cavity 500, for example, the accommodating cavity 500 can be vacuumized, or when the pole core string 600 in the accommodating cavity 500 generates violent air due to abnormal operation, the violent air can burst the explosion-proof structure 200 through the through hole 130, so as to prevent the battery pack from exploding.

In some embodiments, through holes 130 and glue injection holes 131 are provided at different positions of the box 100 corresponding to the accommodating cavities 500, wherein the explosion-proof structures 200 are correspondingly provided on the through holes 130, and the glue injection holes 131 can be sealed by a sealing member after glue injection is completed. That is, in the present embodiment, the through hole 130 is only used for the pole core string 600 in the accommodating chamber 500 to generate violent gas due to abnormal operation, and the explosion-proof structure 200 can be burst through the through hole 130, so as to prevent the explosion of the battery pack.

Referring to fig. 5 again, in a further embodiment, two adjacent pole-core groups 610 in the pole-core string 600 are electrically connected through a conductive member 620, and the glue injection hole 131 is disposed corresponding to the conductive member 620. The glue injection hole 131 is arranged corresponding to the conductive piece 620, so that when structural glue is injected into the glue injection hole 131, the structural glue is further glued to the connecting positions of the two adjacent pole core groups 610 in the pole core string 600, and the structural stability of the pole core string 600 is improved.

Referring to fig. 3 and 4, in a further embodiment, the explosion-proof structure 200 includes a cover 210 hermetically connected to the box 100 and a protrusion 220 disposed on the cover 210, the protrusion 220 protrudes toward a side away from the pole core set 610, and a peripheral wall of the protrusion 220 is formed with a weak area 230. The weak region 230 may be a groove recessed from the outer circumferential wall to one side of the through hole 130, or the thickness of the weak region 230 is less than the thickness of the rest of the explosion-proof structure 200; the outer peripheral wall refers to a surface of the projection 230 on a side facing away from the pole core group 610. Since the weak region 230 is thinner than the rest of the explosion-proof structure 200, when the pole piece string 600 in the accommodating cavity 500 generates violent gas due to abnormal operation and can pass through the through hole 130 to act on the explosion-proof structure 200, the weak region 230 is exploded earlier than the other parts of the explosion-proof structure 200, so as to exhaust the violent gas, thereby performing an explosion-proof function on the battery pack and preventing the battery pack from being damaged.

In a further embodiment, at least one of the top plate 121 and the bottom plate 122 is provided with said through hole 130. That is, the top plate 121 is provided with the through hole 130, or the bottom plate 122 is provided with the through hole 130, or both the top plate 121 and the bottom plate 122 are provided with the through holes 130, in some embodiments, the through hole 130 corresponding to a part of the accommodating cavity 500 may be provided on the top plate 121, and the through hole 130 corresponding to another part of the accommodating cavity 500 may be provided on the bottom plate 122.

In a further embodiment, the box body 100 further includes a first edge beam 123 and a second edge beam 124 (shown in fig. 1) distributed on two sides of the box body 110 along a third direction Z, where the first direction X is a length direction of the box body 100, and the third direction Z is a width direction of the box body 100; alternatively, the first direction X is a width direction of the casing 100, and the third direction Z is a length direction of the casing 100.

Referring to fig. 9, in a further embodiment, the box body 110 includes a plurality of connected sub-boxes 120, and the plurality of sub-boxes 120 are sequentially arranged along a third direction Z; the sub-boxes 120 located at both ends in the third direction Z among the plurality of sub-boxes 120 are end sub-boxes 1201, one of the two end sub-boxes 1201 is connected to the first edge beam 123, and the other is connected to the second edge beam 124. The other sub-tank 120 between the two end sub-tanks 1201 comprises only the top plate 121, the bottom plate 122 and the structural beam 400 in between.

In further embodiments, the end sub-tank 1201 connected to the first side rail 123 is integrally formed with the first side rail 123 (as shown in FIG. 12), and/or the end sub-tank 1201 connected to the second side rail 124 is integrally formed with the second side rail 124. Thus, not only can the processing technology be simplified and the cost be reduced, but also the structural strength of the box body 100 can be further improved by the integrally formed structure. For example, one of the end sub-cases 1201 and the first side member 123 may be formed by integral extrusion, and the other end sub-case 1201 and the second side member 124 may be formed by integral extrusion.

In a further embodiment, at least one of the top plate 121 and the bottom plate 122 is integrally formed with the structural beam 400. Preferably, the top plate 121, the bottom plate 122 and the structural beam 400 therebetween are integrally formed to form the sub-tank 120 with higher structural strength.

In a further embodiment, a plurality of structural beams 400 are arranged in the sub-box body 120, the structural beams 400 are distributed at intervals along a third direction Z, the length of each structural beam 400 extends along a first direction X, each structural beam 400 is connected to the top plate 121 and the bottom plate 122, the first direction X is the width direction of the box body 100, and the third direction Z is the length direction of the box body 100; alternatively, the first direction X is a longitudinal direction of the casing 100, and the third direction Z is a width direction of the casing 100.

In a further embodiment, the length of the receiving cavity 500 along the first direction X is greater than 500mm, and further, the length of the receiving cavity 500 along the first direction is 500mm to 2500 mm. By such a design, the pole core string 600 disposed in the accommodating cavity 500 can have a longer length, that is, can accommodate more pole core groups 610, so that the battery pack can meet the requirements of larger capacity and higher space utilization. Further, the length of the receiving cavity 500 in the second direction is 1000mm to 2000 mm. Further, the length of the receiving cavity 300 in the second direction is 1300mm to 2200 mm.

The pole string 600 is preferably a pole string 600 having a length greater than 400mm in the present application. Further, the pole core string 600 has a length of 400mm to 2500 mm. Further, the pole core string 600 has a length of 1000mm to 2000 mm. Further, the pole core string 600 has a length of 1300mm to 2200 mm. It can be understood that, by arranging a plurality of pole-core groups 610 in series to form the pole-core string 600 in the accommodation cavity 500, the internal resistance can be reduced as compared with the conventional case where only one pole-core group 610 having the same length as the pole-core string 600 is arranged. Because, once the longer the pole core group 610 is, the length of the copper aluminum foil used as the current collector is increased correspondingly, the internal resistance is greatly improved, the current requirements of higher and higher power and quick charging can not be met, and the problem can be avoided by adopting the serial connection mode of the plurality of pole core groups 610.

In a further embodiment, the tank body 110 has a first end and a second end opposite along the first direction X, at least one of the first end and the second end of the tank body 110 is provided with an opening 150 (as shown in fig. 6), and the tank body 100 further includes an end plate 160 (as shown in fig. 8) closing the opening 150. When both ends of the tank body 110 have the openings 150, both ends of the tank body 110 have two end plates 160 for closing the openings 150 of both ends. In some embodiments, one end of the tank body 110 in the first direction X itself has an end plate that closes the opening without an additional end plate, that is, one end of the tank body 110 in the first direction X is closed and the other end has the opening 150.

In a further embodiment, the tank body 110 includes a plurality of connected sub-tanks 120, the opening 150 of the tank body 110 includes a sub-opening 151 (shown in FIG. 9) corresponding to each sub-tank 120, and the end plate 160 includes a plurality of sub-end plates, each sub-end plate closing each sub-opening 151. For example, in the present embodiment, the box body 110 includes three connected sub-boxes 120 having three corresponding sub-openings 151, and three sub-end plates 161 respectively closing the three corresponding sub-openings 151.

In a further embodiment, the battery pack 10 further includes an insulating bracket 170 (shown in fig. 7) located inside the end plate 160, and the insulating bracket 170 is provided at the opening 150 of at least one of the first and second ends of the case body 110. Wherein the inner side of the end plate 160 refers to the side of the end plate 160 close to the pole core group 610. The insulating support 170 may be a split structure, that is, includes a plurality of sub-supports, and each sub-support is correspondingly disposed at the sub-opening 151 of each sub-box 120; the insulating support 170 can also be of an integrated structure, the integrated structure can simplify the processing technology, and the split structure can be used for replacing the sub-support corresponding to the sub-box 120, so that the operation is simplified, and the cost is saved.

The two polar core groups 610 which are positioned at the same end of the box body in the first direction X and are respectively positioned in the two adjacent accommodating cavities 500 are electrically connected through the electric connector 190, and the electric connector 190 is fixed on the insulating bracket 170. Wherein the electrical connector 190 may be fixed to a side of the insulation bracket 170 away from the pole core set 610.

In a further embodiment, the battery pack 10 further includes a protective cover 180 (shown in fig. 8) positioned between the insulating support 170 and the end plate 160. The protective cover 180 may be a split structure, that is, includes a plurality of sub-protective covers, and each sub-protective cover is correspondingly disposed at the sub-opening 151 of each sub-box 120; the protective cover 180 can also be of an integrated structure, the integrated structure can simplify the processing technology, and the split structure can be replaced by detaching the sub protective cover corresponding to the sub box body 120, so that the operation is simplified, and the cost is saved.

Referring to fig. 19 and 20, in a further embodiment, the pole piece string 600 has a length greater than 400 mm; the pole core group 610 includes a first electrode drawing part 611 and a second electrode drawing part 612 for drawing current, the first electrode drawing part 611 and the second electrode drawing part 612 are distributed on opposite sides of the pole core group 610 along the first direction X, and the first electrode drawing part 611 of one pole core group 610 of two adjacent pole core groups 610 constituting the pole core string 600 is electrically connected with the second electrode drawing part 612 of the other pole core group 610.

In a further embodiment, a plurality of pole core strings 600 are disposed in the accommodating cavity 500, the plurality of pole core strings 600 are sequentially arranged and electrically connected along the thickness direction of the pole core group 610, the thickness direction of the pole core group 610 is parallel to a third direction Z, the first direction X is the length direction of the box 100, and the third direction Z is the width direction of the box 100; alternatively, the first direction X is a width direction of the casing 100, and the third direction Z is a length direction of the casing 100.

Referring to fig. 13 to 15, in a further embodiment, the first pole-core group 610 of one pole-core string 600 of two adjacent pole-core strings 600 is electrically connected to the first pole-core group 610 of the other pole-core string 600 (as shown in fig. 13), or the last pole-core group 610 of one pole-core string 600 of two adjacent pole-core strings 600 is electrically connected to the last pole-core group 610 of the other pole-core string 600 (as shown in fig. 14), so that the plurality of pole-core strings 600 in the same accommodating cavity 500 are connected in series.

Specifically, when a plurality of pole core strings 600 in the same accommodating cavity 500 are connected in series, the first electrode lead-out part 611 of the first pole core group 610 of one pole core string 600 in two adjacent pole core strings 600 is located at the same end as the second electrode lead-out part 612 of the first pole core group 610 of the other pole core string 600 and is electrically connected through the electrical connector, or the first electrode lead-out part 611 of the last pole core group 610 of one pole core string 600 in two adjacent pole core strings 600 is located at the same end as the second electrode lead-out part 612 of the last pole core group 610 of the other pole core string 600 and is electrically connected through the electrical connector.

Alternatively, the second electrode lead-out member 612 of the first pole-core group 610 of one pole-core string 600 of the two adjacent pole-core strings 600 is located at the same end as the first electrode lead-out member 611 of the first pole-core group 610 of the other pole-core string 600 and is electrically connected thereto through an electrical connection member, or the second electrode lead-out member 612 of the last pole-core group 610 of one pole-core string 600 of the two adjacent pole-core strings 600 is located at the same end as the first electrode lead-out member 611 of the last pole-core group 610 of the other pole-core string 600 and is electrically connected thereto through an electrical connection member.

Alternatively, the first pole-core group 610 of one pole-core string 600 in two adjacent pole-core strings 600 is electrically connected with the first pole-core group 610 of the other pole-core string 600 (as shown in fig. 15), and the last pole-core group 610 of one pole-core string 600 in two adjacent pole-core strings 600 is electrically connected with the last pole-core group 610 of the other pole-core string 600, so that a plurality of pole-core strings 600 in the same accommodating cavity 500 are connected in parallel.

Specifically, when a plurality of pole core strings 600 in the same accommodating cavity 500 are connected in parallel, the first electrode lead-out member 611 of the first pole core group 610 of one pole core string 600 in two adjacent pole core strings 600 is located at the same end as the first electrode lead-out member 611 of the first pole core group 610 of the other pole core string 600 and is electrically connected thereto through an electrical connector, and the second electrode lead-out member 612 of the last pole core group 610 of one pole core string 600 in two adjacent pole core strings 600 is located at the same end as the second electrode lead-out member 612 of the last pole core group 610 of the other pole core string 600 and is electrically connected thereto through an electrical connector.

Referring to fig. 16 to 18, in a further embodiment, the first pole-core group 610 of one pole-core string 600 in one accommodation cavity 500 of two adjacent accommodation cavities 500 is electrically connected to the first pole-core group 610 of one pole-core string 600 in the other accommodation cavity 500 (as shown in fig. 16), or the last pole-core group 610 of one pole-core string 600 in one accommodation cavity 500 of two adjacent accommodation cavities 500 is electrically connected to the last pole-core group 610 of one pole-core string 600 in the other accommodation cavity 500 (as shown in fig. 17), so that the pole-core strings 600 in two adjacent accommodation cavities 500 are connected in series.

Specifically, when the pole core strings 600 in two adjacent accommodating cavities 500 are connected in series, the first electrode lead-out part 611 of the first pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 and the second electrode lead-out part 612 of the first pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 are located at the same end and penetrate through the insulating support 170 and are electrically connected through the electric connecting piece, or the first electrode lead-out part 611 of the last pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 and the second electrode lead-out part 612 of the last pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 are located at the same end and penetrate through the insulating support 170 and are electrically connected through the electric connecting piece.

Alternatively, the second electrode lead-out member 612 of the first pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 is located at the same end as the first electrode lead-out member 611 of the first pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 and passes through the insulating support 170 and is electrically connected thereto, or the second electrode lead-out member 612 of the last pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 is located at the same end as the second electrode lead-out member 612 of the last pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 and passes through the insulating support 170 and is electrically connected thereto via an electrical connection member.

Alternatively, the first pole-core group 610 of one of the pole-core strings 600 in one of the two adjacent accommodating cavities 500 is electrically connected to the first pole-core group 610 of one of the pole-core strings 600 in the other accommodating cavity 500 (as shown in fig. 18), and the last pole-core group 610 of one of the pole-core strings 600 in one of the two adjacent accommodating cavities 500 is electrically connected to the last pole-core group 610 of one of the pole-core strings 600 in the other accommodating cavity 500, so that the pole-core strings 600 in the two adjacent accommodating cavities 500 are connected in parallel.

Specifically, when the pole core strings 600 in two adjacent accommodating cavities 500 are connected in parallel, the first electrode lead-out part 611 of the first pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 and the first electrode lead-out part 612 of the first pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 are located at the same end and penetrate through the insulating support 170 and are electrically connected through the electrical connector, and the second electrode lead-out part 612 of the last pole core group 610 of one of the pole core strings 600 in one of the two adjacent accommodating cavities 500 and the second electrode lead-out part 612 of the last pole core group 610 of one of the pole core strings 600 in the other accommodating cavity 500 are located at the same end and penetrate through the insulating support 170 and are electrically connected through the electrical connector.

Referring to fig. 19, in a further embodiment, a plurality of pole-core groups 610 constituting a pole-core string 600 are encapsulated in an encapsulation film 700; the pole core group 610 comprises a pole core group main body 613, and a first electrode lead-out part 611 and a second electrode lead-out part 612 for leading out current, wherein the connection position of the first electrode lead-out part 611 of one pole core group 610 and the second electrode lead-out part 612 of the other pole core group 610 in the two pole core groups 610 connected in series is positioned in the encapsulation film 700; the encapsulation film 700 is formed with an encapsulation part 614 at a position opposite to the first electrode drawing part 611 and/or the second electrode drawing part 612 to isolate the adjacent two-pole core pack bodies 613.

Referring to fig. 20, in some embodiments, each of the pole core assemblies 610 is encapsulated in an encapsulation film 700 to form pole core assemblies 630, and the pole core assemblies 630 are connected in series.

Referring to fig. 1 and 8 again, in a further embodiment, the box body 100 further includes a first edge beam 123 and a second edge beam 124 distributed on two sides of the box body 110 along the third direction Z; a plurality of structural beams 400 are arranged in the sub-box body 120, the structural beams 400 are distributed at intervals along the third direction Z, the length direction of each structural beam 400 is parallel to the first direction X, and each structural beam 400 is connected to the top plate 121 and the bottom plate 122; at least one of the top plate 121 and the bottom plate 122 is integrally formed with the structural beam 400. The tank body 110 has a first end and a second end opposite to each other in the first direction X, at least one of the first end and the second end of the tank body 110 is provided with an opening 150, and the tank body 100 further includes an end plate 160 (shown in fig. 8) closing the opening 150. Wherein, the first direction X is the width direction of the box body 100, and the third direction Z is the length direction of the box body 100; alternatively, the first direction X is a longitudinal direction of the casing 100, and the third direction Z is a width direction of the casing 100.

In the present embodiment, the box body 110 includes a top plate 121, a bottom plate 122 and a structural beam 400 therebetween, and the box body 110 is an integrally formed structure. Wherein the first edge beam 123, the second edge beam 124 and the two end plates 160 can be hermetically connected to the tank body 110 by welding to form the sealed tank 100.

The present application further provides an electric vehicle comprising a vehicle body and the battery pack as described in any one of the above, wherein the battery pack is passed through the mounting portion is fixed to the vehicle body. The application provides an electric motor car, when above-mentioned higher battery package of structural strength installs on whole car, the structural strength of battery package can regard as a part of whole car structural strength to can promote the structural strength of whole car, be favorable to realizing the light-weighted design requirement of whole car of electric automobile, also reduce the design and the manufacturing cost of whole car simultaneously. And, be equipped with explosion-proof valve structure on the box of battery package, be favorable to improving the security that electric motor car and battery package used.

The above examples only show some embodiments of the present invention, and the description thereof is more detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The battery pack is characterized by comprising a box body, an explosion-proof structure and a plurality of pole core strings which are positioned in the box body and are electrically connected with each other;

2. The battery pack of claim 1, wherein each of the receiving cavities is in communication with at least one of the through-holes.

3. The battery pack according to claim 1, wherein one of the plurality of receiving cavities is in communication with at least one of the through holes, and the receiving cavity is in communication with the remaining receiving cavities.

4. The battery pack of claim 1, wherein the sub-case includes a top plate and a bottom plate oppositely disposed in a second direction, the second direction being a height direction of the case, the structural beams being located between the top plate and the bottom plate, at least one of the structural beams being connected to the top plate and the bottom plate.

5. The battery pack of claim 1, wherein the through-holes are glue injection holes.

6. The battery pack according to claim 5, wherein two adjacent pole core groups in the pole core string are electrically connected through a conductive member, and the glue injection hole is provided corresponding to the conductive member.

7. The battery pack according to claim 1, wherein the explosion-proof structure includes a cover body sealingly connected to the case body, and a protrusion provided on the cover body, the protrusion protruding toward a side away from the electrode core group, and a peripheral wall of the protrusion having a weak area formed thereon.

8. The battery pack of claim 4, wherein at least one of the top and bottom plates is provided with the through-hole.

9. The battery pack of claim 1, wherein the case body further comprises a first edge beam and a second edge beam distributed on both sides of the case body along a third direction, the first direction being a length direction of the case body, the third direction being a width direction of the case body; or, the first direction is the width direction of the box body, and the third direction is the length direction of the box body.

10. The battery pack according to claim 9, wherein the case body includes a plurality of connected sub-case bodies, the plurality of sub-case bodies being sequentially arranged in the third direction;

the sub-boxes positioned at the two ends in the third direction in the plurality of sub-boxes are end part sub-boxes, one of the two end part sub-boxes is connected with the first edge beam, and the other end part of the two end part sub-boxes is connected with the second edge beam.

11. The battery pack according to claim 10, wherein the end sub-case connected to the first side member and the first side member are integrally formed, and/or the end sub-case connected to the second side member and the second side member are integrally formed.

12. The battery pack of claim 4, wherein at least one of the top and bottom plates is integrally formed with the structural beam.

13. The battery pack of claim 4, wherein the sub-case has a plurality of structural beams spaced apart along a third direction, a length of each of the structural beams extending along a first direction, each of the structural beams being connected to the top plate and the bottom plate, the first direction being a width direction of the sub-case, and the third direction being a length direction of the sub-case; or, the first direction is the length direction of the box body, and the third direction is the width direction of the box body.

14. The battery pack of claim 1, wherein the receiving cavity has a length in the first direction greater than 500 mm.

15. The battery pack of claim 1, wherein the case body has first and second ends opposite in the first direction, at least one of the first and second ends of the case body is provided with an opening, and the case body further includes an end plate closing the opening.

16. The battery pack of claim 15, wherein the case body comprises a plurality of connected sub-cases, the opening of the case body comprises a sub-opening corresponding to each of the sub-cases, and the end plate comprises a plurality of sub-end plates, the sub-end plates correspondingly closing the sub-openings.

17. The battery pack of claim 1, wherein the pole piece string has a length greater than 400 mm; the pole core group comprises a first electrode leading-out part and a second electrode leading-out part which are used for leading out current, the first electrode leading-out part and the second electrode leading-out part are distributed on two opposite sides of the pole core group along the first direction, and the first electrode leading-out part of one pole core group in two adjacent pole core groups forming the pole core string is electrically connected with the second electrode leading-out part of the other pole core group.

18. The battery pack according to claim 17, wherein a plurality of the pole core strings are disposed in the accommodating cavity, the plurality of pole core strings are sequentially arranged in a thickness direction of the pole core group and are electrically connected, the thickness direction of the pole core group is parallel to a third direction, the first direction is a length direction of the case, and the third direction is a width direction of the case; or, the first direction is the width direction of the box body, and the third direction is the length direction of the box body.

19. The battery pack according to claim 18, wherein the first pole group of one of the two adjacent pole strings is electrically connected to the first pole group of the other pole string, or the last pole group of one of the two adjacent pole strings is electrically connected to the last pole group of the other pole string, so that the plurality of pole strings in the same accommodation cavity are connected in series; or the like, or, alternatively,

the first pole core group of one pole core string in two adjacent pole core strings is electrically connected with the first pole core group of the other pole core string, and the last pole core group of one pole core string in two adjacent pole core strings is electrically connected with the last pole core group of the other pole core string, so that the same is contained in the accommodating cavity, and the pole core strings are connected in parallel.

20. The battery pack according to claim 18, wherein the first pole core group of one of the pole core strings in one of the adjacent two receiving cavities is electrically connected to the first pole core group of one of the pole core strings in the other receiving cavity, or the last pole core group of one of the pole core strings in one of the adjacent two receiving cavities is electrically connected to the last pole core group of one of the pole core strings in the other receiving cavity, so that the pole core strings in the adjacent two receiving cavities are connected in series; or the like, or, alternatively,

the first pole core group of one of them pole core cluster in one of them holds the intracavity in two adjacent holding cavities is connected with the first pole core group electricity of one of them pole core cluster in another holding cavity, and the last pole core group of one of them pole core cluster in one of them holding cavity in two adjacent holding cavities is connected with the last pole core group of one of them pole core cluster in another holding cavity electrically to make the pole core cluster in two adjacent holding cavities connect in parallel.

21. The battery pack of claim 1, wherein the plurality of pole core groups making up the pole core string are encapsulated in an encapsulation film; the pole core group comprises a pole core group main body, a first electrode leading-out part and a second electrode leading-out part, wherein the first electrode leading-out part and the second electrode leading-out part are used for leading out current; and the packaging part is formed at the position of the packaging film opposite to the first electrode lead-out part and/or the second electrode lead-out part so as to separate the adjacent two polar core group main bodies.

22. The battery pack according to claim 1, wherein each of the pole core groups is encapsulated in an encapsulating film to form pole core assemblies, and the pole core assemblies are connected in series.

23. The battery pack of claim 4, wherein the case body further comprises a first edge beam and a second edge beam distributed on both sides of the case body in a third direction;

a plurality of structural beams are arranged in the sub-box body and are distributed at intervals along a third direction, the length direction of each structural beam is parallel to the first direction, and each structural beam is connected to the top plate and the bottom plate; at least one of the top plate and the bottom plate is integrally formed with the structural beam;

the box body is provided with a first end and a second end which are opposite along the first direction, at least one of the first end and the second end of the box body is provided with an opening, and the box body further comprises an end plate for closing the opening;

the first direction is the width direction of the box body, and the third direction is the length direction of the box body; or, the first direction is the length direction of the box body, and the third direction is the width direction of the box body.

24. An electric vehicle comprising a vehicle body and the battery pack according to any one of claims 1 to 23, wherein the battery pack is fixed to the vehicle body by the mounting portion.