CN114512749A

CN114512749A - Top cover of lithium ion battery

Info

Publication number: CN114512749A
Application number: CN202011156442.7A
Authority: CN
Inventors: 刘宏; 胡中良; 陈晓兵; 谢世平
Original assignee: Kunshan Ju Innovative Energy Technology Co Ltd
Current assignee: Kunshan Ju Innovative Energy Technology Co Ltd
Priority date: 2020-10-26
Filing date: 2020-10-26
Publication date: 2022-05-17

Abstract

The invention discloses a top cover of a lithium ion battery, which comprises: the lamina tecti with locate anodal post and negative pole post on the lamina tecti and the piece that converges, wherein, the piece that converges is located anodal post with the lower extreme of negative pole post, the piece that converges includes: the first sub-bus-bar piece, the second sub-bus-bar piece and the connecting piece are arranged between the first sub-bus-bar piece and the second sub-bus-bar piece, and the first sub-bus-bar piece and the second sub-bus-bar piece are respectively suitable for being matched with two electric core groups of the lithium ion battery. According to the top cover of the lithium ion battery, the bus bar is divided into the first bus bar, the second bus bar and the connecting piece, so that each electric core group can be provided with an independent current channel, the interference among the electric core groups is reduced, meanwhile, the heat accumulation at the bus bar can be well avoided, the structure is ingenious, the anti-interference capability is high, and the safety is high.

Description

Top cover of lithium ion battery

Technical Field

The invention relates to the technical field of lithium ion battery production, in particular to a top cover of a lithium ion battery.

Background

In the prior art, lithium ion battery is widely applied to a plurality of fields, and in the current lithium ion battery production process, the connection position between top cover and electric core occupies too much space, and the connection is fragile, so that in the use process of the battery, the connection between electric core and top cover is easy to break, resulting in greatly reduced use safety of the lithium ion battery.

On the other hand, in the prior art, a plurality of groups of battery cells commonly share the same bus assembly, which results in heat accumulation at the connection position between the battery cell and the bus assembly, or thermal runaway of the lithium ion battery, and poor safety.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention aims to provide the top cover of the lithium ion battery, which has the advantages of ingenious structure, strong anti-interference capability and good practicability.

The lithium ion battery top cover according to the embodiment of the invention comprises: the top cover plate is provided with a positive pole column and a negative pole column which are arranged on the top cover plate; the piece that converges, it locates to converge the piece the positive post with the lower extreme of negative pole post, it includes to converge the piece: the first sub-bus-bar piece, the second sub-bus-bar piece and the connecting piece are arranged between the first sub-bus-bar piece and the second sub-bus-bar piece, and the first sub-bus-bar piece and the second sub-bus-bar piece are respectively suitable for being matched with two electric core groups of the lithium ion battery.

According to the top cover of the lithium ion battery, the bus bar is divided into the first bus bar, the second bus bar and the connecting piece, so that each electric core group can be provided with an independent current channel, interference among the electric core groups is reduced, meanwhile, heat can be well prevented from being accumulated at the bus bar, the structure is ingenious, the anti-interference capability is high, and the safety is high.

In addition, the top cover of the lithium ion battery according to the embodiment of the invention can also have the following technical characteristics:

in some embodiments of the present invention, the first sub bus bar includes: the first electric connecting piece is suitable for being connected with a lug of one electric core group; and one end of the first bending piece is connected with the middle part of the first electric connector, and the other end of the first bending piece extends upwards in an S-shaped bending mode and then extends towards the direction of the second sub-bus piece.

Further, the second sub bus bar includes: the second electric connecting piece is suitable for being connected with the pole lug of the other electric core group; and one end of the second bending piece is connected with the middle part of the second electric connecting piece, the other end of the second bending piece extends upwards in an S-shaped bending mode and then extends towards the direction of the first sub-collecting piece, and the first bending piece is not in contact with the second bending piece.

Preferably, first bending member orientation the upside face of the one end of second bending member has first inclined plane, the second bending member orientation the upside face of the one end of first bending member has the second inclined plane, the both ends of connecting piece be formed with respectively with first inclined plane with the complex fitting surface of second inclined plane.

In other embodiments of the present invention, the top cap of the lithium ion battery further comprises: a lower molding member, the lower molding member is located the lower extreme of lamina tecti, the lower molding member includes: the anti-explosion valve comprises a first sub-injection molding part and a second sub-injection molding part, wherein the first sub-injection molding part and the second sub-injection molding part are spaced, a positioning groove corresponding to the anti-explosion valve is formed in one of the first sub-injection molding part and the second sub-injection molding part, and anti-explosion meshes are formed in the positioning groove.

Preferably, the positive post is adapted to be die cast between the top cover plate and the first sub injection molded part, and the negative post is adapted to be die cast between the top cover plate and the second sub injection molded part.

In still other embodiments of the present invention, the top cover plate has a positive post positioning groove and a negative post positioning groove formed thereon, the positive post has a positive post positioning plate formed thereon that engages with the positive post positioning groove, and the negative post has a negative post positioning plate formed thereon that engages with the negative post positioning groove.

Further, the top cap of the lithium ion battery further comprises: an upper injection molded part, the upper injection molded part comprising: positive post injection molding and negative pole post injection molding, the projection of positive post injection molding with the projection coincidence of positive post locating plate, the projection of negative pole post injection molding with the projection coincidence of negative pole post locating plate.

Optionally, a positive post positioning hole allowing the positive post to extend out is formed in the positive post injection molding piece, and a negative post positioning hole allowing the negative post to extend out is formed in the negative post injection molding piece.

Optionally, in the up-down direction, a first limit groove is formed in the middle of the positive post, a second limit groove is formed in the middle of the negative post, a first limit table matched with the first limit groove is formed on the positive post injection molding, and a second limit table matched with the second limit groove is formed on the negative post injection molding.

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

Drawings

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

fig. 1 is an exploded view of a top cover of a lithium ion battery according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a bus bar of a top cap of a lithium ion battery according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a top cover of a lithium ion battery according to an embodiment of the present invention;

fig. 4 is a top view of a top cover of a lithium ion battery according to an embodiment of the invention;

fig. 5 is a cross-sectional view of a top cap of a lithium ion battery according to an embodiment of the present invention along the positive and negative post axes;

FIG. 6 is a schematic structural view of a first sub-injection molded part of a top cover of a lithium ion battery according to an embodiment of the invention;

FIG. 7 is a schematic structural view of a second sub-injection molded part of a top cover of a lithium ion battery according to an embodiment of the invention;

fig. 8 is a schematic structural view of a positive post injection molding (negative post injection molding) of a top cap of a lithium ion battery according to an embodiment of the present invention;

fig. 9 is a schematic structural view of a positive electrode tab (negative electrode tab) of a top cap of a lithium ion battery according to an embodiment of the present invention.

Reference numerals:

100: a top cover of the lithium ion battery;

1: a top cover plate; 11: a positive post positioning groove; 12: a cathode post positioning groove;

2: a positive post; 21: a positive pole positioning plate; 22: a first limit groove;

3: a negative pole post; 31: a negative pole positioning plate; 32: a second limit groove;

4: a bus bar; 41: a first sub bus bar; 411: a first electrical connection; 412: a first bending member; 42: a second sub bus bar; 421: a second electrical connection; 422: a second bending member; 43: a connecting member;

5: a lower injection molding piece; 51: a first sub-injection molded part; 52: a second sub-injection molded part; 521: positioning a groove; 522: explosion-proof mesh;

6: an upper injection molding piece; 61: a positive post injection molding; 611: a positive post locating hole; 612: a first limit table; 62: a negative pole column injection molding piece; 621: a cathode post positioning hole; 622: a second limit table;

7: an explosion-proof valve; 8: and (5) sealing rings.

Detailed Description

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

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not 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 description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; 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.

A top cap 100 of a lithium ion battery according to an embodiment of the present invention is described below with reference to fig. 1 to 9.

The top cover 100 of the lithium ion battery according to the embodiment of the present invention includes: top cover plate 1, positive post 2, negative post 3 and conflux piece 4.

Wherein, positive post 2 and negative pole post 3 are located on the lamina tecti 1, from this, can realize the independent production of lamina tecti 1, positive post 2 and negative pole post 3, have reduced the production degree of difficulty. Specifically, anodal post 2 and negative pole post 3 can be connected with consumer better to make the inside electric energy of lithium ion battery export to consumer through anodal post 2 and negative pole post 3, simultaneously, when anodal post 2 and negative pole post 3 are connected to battery charging outfit, the electric energy of being convenient for is lithium ion battery's through anodal post 2 and negative pole post 3 and charges, simple structure. Further, after the top cover 100 is assembled to the lithium ion battery, since the top cover plate 1 is located on the outer side of the top cover 100, the top cover plate 1 can better prevent foreign matters from entering the inside of the lithium ion battery, so that the internal structure of the lithium ion battery is better protected, and the safety is good.

As shown in fig. 1 and 5, the confluence part 4 is disposed at the lower end of the positive post 2 and the negative post 3, that is, the positive post 2 and the negative post 3 are both connected with the electric core group through the confluence part 4, and in the production process of the lithium ion battery, in order to improve the endurance capacity of the lithium ion battery, usually, not only one electric core group is disposed inside the lithium ion battery, therefore, the confluence part 4 can better communicate the positive poles of all the electric core groups of the lithium ion battery with the positive post 2, and communicate the negative poles of all the electric core groups with the negative post 3, the structure is simple, and the confluence effect is good. Wherein the positive pole post 2 and the negative pole post 3 are provided with independent confluence pieces 4.

Further, referring to fig. 1 and 2, the bus bar 4 includes: the first sub-collecting assembly 41, the second sub-collecting assembly 42 and the connecting member 43 are arranged between the first sub-collecting assembly 41 and the second sub-collecting assembly 42, the first sub-collecting assembly 41 and the second sub-collecting assembly 42 are respectively suitable for being matched with two cell groups of the lithium ion battery, that is, the anodes of the two cell groups are respectively connected with the connecting member 43 through the first sub-collecting assembly 41 and the second sub-collecting assembly 42 and then connected with the positive post 2 through the connecting member 43, so that a passage is formed between the anodes of the two cell groups and the positive post 2, the cathodes of the two cell groups are respectively connected with the connecting member 43 through the first sub-collecting assembly 41 and the second sub-collecting assembly 42 and then connected with the negative post 3 through the connecting member 43, so that a passage is formed between the cathodes of the two cell groups and the negative post 3, thereby realizing the communication between the two cell groups and the positive post 2 and the negative post 3, so as to ensure the stable output of electric energy, And (4) inputting.

Further, the bus bar 4 is divided into the first sub bus bar 41 and the second sub bus bar 42, so that each electric core set can have the independent first sub bus bar 41 or the second sub bus bar 42, and thus, the heat conducted to the bus bar 4 during the charge and discharge of the electric core set can be better distributed by the first sub bus bar 41 and the second sub bus bar 42, and the occurrence of thermal runaway and the like caused by the accumulation of the heat at the bus bar 4 can be avoided.

On the other hand, since the two electric core groups are respectively provided with the corresponding first sub-collecting-current components 41 and the corresponding second sub-collecting-current components 42, if the electric core group communicated with the first sub-collecting-current components 41 fails, the electric core group communicated with the second sub-collecting-current components 42 can still continuously ensure the output of the electric energy to the power supply equipment, therefore, the first sub-collecting-current components 41 and the second sub-collecting-current components 42 are separately arranged, and the influence on the normal-state electric core group when a single electric core group fails is reduced.

According to the top cover 100 of the lithium ion battery provided by the embodiment of the invention, the bus bar 4 is divided into the first sub bus bar 41, the second sub bus bar 42 and the connecting piece 43, so that each electric core group can have an independent current channel, the interference among the electric core groups is reduced, the heat accumulation at the bus bar 4 can be better avoided, the structure is ingenious, the anti-interference capability is strong, and the safety is high.

In some examples, the number of the cell groups in the lithium ion battery may be three, four or five, and each cell group is provided with an independent first sub bus bar 41 or second sub bus bar 42, which is not limited herein.

In some embodiments of the present invention, the first sub bus bar 41 includes: first electric connector 411 and first bending piece 412, specifically, first electric connector 411 is suitable for being connected with the utmost point ear of an electric core group, as shown in fig. 2, be formed with towards the open-ended mounting groove of front end on the first electric connector 411, therefore, the utmost point ear of electric core group can be through installing in the mounting groove, thereby realize being connected of electric core group and first electric connector 411, and, the mounting groove can be in the upper and lower direction centre gripping utmost point ear betterly, assembly process is simple, and, transversely set up the mounting groove, make utmost point ear and first electric connector 411's hookup location can not occupy extra installation space, and is rational in infrastructure, and space utilization is high.

As shown in fig. 2, one end of the first bending member 412 is connected to the middle of the first electrical connector 411, and the other end of the first bending member 412 extends upward in an "S" shaped bending manner and then extends toward the second sub-bus member 42, that is, the first bending member 412 is formed as a transverse groove with an opening facing the second sub-bus member 42 and is disposed through in the front-rear direction, so that the first bending member 412 has a certain deformation angle, and when the cell assembly is shifted upward, the first bending member 412 can reduce the opening angle, thereby generating a certain deformation to buffer the extrusion of the cell assembly, and the structural strength is high.

Further, as shown in fig. 2, the upper side of the extending portion of the first bending member 412 toward the second sub bus bar 42 abuts against the lower side of the connection member 43, so that the contact area between the first bending member 412 and the connection member 43 is large, and the connection stability is increased. In some examples, a fuse may be disposed at the position of the "S" type bending.

Further, the second sub bus bar 42 includes: second electric connector 421 and second bending element 422, specifically, second electric connector 421 is suitable for being connected with the utmost point ear of another electric core group, as shown in fig. 2, be formed with towards rear end open-ended mounting groove on second electric connector 421, from this, the utmost point ear of electric core group can be through installing in the mounting groove, thereby realize being connected of electric core group and second electric connector 421, and, the mounting groove can be in the upper and lower direction centre gripping utmost point ear betterly, assembly process is simple, and, transversely set up the mounting groove, make utmost point ear and second electric connector 421 the hookup location can not occupy extra installation space, rational in infrastructure, space utilization is high.

As shown in fig. 2, one end of the second bending part 422 is connected to the middle of the second electrical connecting part 421, and the other end of the second bending part 422 extends upward in an S-shaped bending manner and then extends toward the first sub-bus bar 41, that is, the second bending part 422 is formed as a transverse groove with an opening facing the first sub-bus bar 41 and is disposed through in the front-rear direction, so that the second bending part 422 has a certain deformation angle, and when the electric core assembly is shifted upward, the second bending part 422 can reduce the opening angle, so that a certain deformation is generated to buffer the extrusion of the electric core assembly, and the structural strength is high.

Further, as shown in fig. 2, the upper side of the extending portion of the second bending part 422 toward the first sub bus bar 41 abuts against the lower side of the connection part 43, so that the contact area between the second bending part 422 and the connection part 43 is large, and the stability of the connection is increased. In some examples, a fuse may be disposed at the position of the "S" bend.

Preferably, the first bending part 412 is not in contact with the second bending part 422, so that the connection between the two cell sets and the connecting part 43 is independent, thereby reducing the possibility of mutual interference between the cell sets and having a high safety factor.

Further, the upper side of the first bending part 412 facing to the end of the second bending part 422 is provided with a first inclined surface, the upper side of the second bending part 422 facing to the end of the first bending part 412 is provided with a second inclined surface, two ends of the connecting part 43 are respectively provided with a matching surface matched with the first inclined surface and the second inclined surface, as shown in fig. 2, the sectional area of the first bending part 412 in the up-down direction is gradually reduced in the direction facing to the second bending part 422, the sectional area of the second bending part 422 in the up-down direction is gradually reduced in the direction facing to the first bending part 412, and the first inclined surface and the matching surface are matched, so that the connection between the first bending part 412 and the second bending part 422 and the connecting part 43 is realized, the structure is ingenious, and the connection is stable.

In some embodiments of the present invention, the top cap 100 further includes a lower molding member 5, and the lower molding member 5 is disposed at the bottom end of the top cap plate 1, so that when the top cap 100 is assembled to the lithium ion battery, the lower molding member 5 can better separate the top cap plate 1 from the electric core assembly, and has a good insulation effect.

Further, the lower molding 5 includes: the first sub-injection-molded part 51 and the second sub-injection-molded part 52 are spaced apart from each other, so that the positive and

negative poles

2 and 3 can be mounted separately.

Further, a positioning groove 521 corresponding to the explosion-proof valve 7 is formed in one of the first sub-injection-molded part 51 and the second sub-injection-molded part 52, as shown in fig. 7, the positioning groove 521 is formed in the second sub-injection-molded part 52, and the positioning groove 521 is formed as a groove which is recessed downward, so that after the second sub-injection-molded part 52 is mounted on the bottom end of the top cover plate 1, the explosion-proof valve 7 can be well placed in a containing space formed between the positioning groove 521 and the bottom end of the top cover plate 1, so as to ensure that the explosion-proof valve 7 cannot be separated from the circumferential limit of the positioning groove 521 in the use process of the lithium ion battery, and therefore, under the condition that the lithium ion battery is out of control due to thermal runaway, the explosion or combustion caused by accumulation of high-temperature high-pressure gas in the battery can be better discharged by the explosion-proof valve 7, and the safety factor is high.

Further, explosion-proof mesh 522 is formed in the positioning groove 521, that is, a plurality of through holes penetrating through the positioning groove 521 are formed in the bottom of the positioning groove 521, so that high-temperature and high-pressure gas generated when the battery is out of thermal control can flow to the explosion-proof valve 7 in the mounting groove 521 through the explosion-proof mesh 522, and then the battery is upwards discharged by breaking the explosion-proof valve 7, in other words, the explosion-proof mesh 522 improves the discharge efficiency of the high-temperature and high-pressure gas, and the safety coefficient is high.

Optionally, the positive post 2 is suitable for being die-cast between the top cover plate 1 and the first sub-injection-molded part 51, and the negative post 3 is suitable for being die-cast between the top cover plate 1 and the second sub-injection-molded part 52, that is, the positive post 2 and the negative post 3 are connected with the top cover plate 1 through a die-casting process, so that the overall connection structure is firm, the falling is avoided, and the safety is good

In other embodiments of the present invention, the top cover plate 1 is formed with the positive post positioning groove 11 and the negative post positioning groove 12, that is, the top cover plate 1 is formed with the through hole for placing the positive post 2 and the negative post 3, which is convenient for the positioning and installation of the positive post 2 and the negative post 3, the assembly process is simple, and the positive post 2 can better extend out of the upper surface of the top cover plate 1 through the positive post positioning groove 11, and the negative post 3 can better extend out of the upper surface of the top cover plate 1 through the negative post positioning groove 12, so as to ensure that the part of the positive post 2 and the negative post 3 extending out of the top cover plate 1 can be better connected with the electric equipment and other devices. Another convenience, the positive post positioning groove 11 and the negative post positioning groove 12 can better limit the positive post 2 and the negative post 3 located therein, so as to ensure that the offset of the positive post 2 and the negative post 3 does not exceed the circumferential range of the positive post positioning groove 11 and the negative post positioning groove 12.

Furthermore, a positive pole positioning plate 21 matched with the positive pole positioning groove 11 is formed on the positive pole 2, a negative pole positioning plate 31 matched with the negative pole positioning groove 12 is formed on the negative pole 3, as shown in fig. 9, positive and negative

post positioning plates

21 and 31 are provided at the bottom ends of the positive and

negative posts

2 and 3, therefore, after the positive pole 2 and the negative pole 3 are respectively arranged in the positive pole positioning groove 11 and the negative pole positioning groove 12, the positive pole positioning plate 21 is matched with the positive pole positioning groove 11, the negative pole positioning plate 31 is matched with the negative pole positioning groove 12, so that form fixed connection between positive post locating plate 21 and the positive post constant head tank 11, between negative pole post locating plate 31 and the negative pole post constant head tank 12, that is to say, form fixed connection between positive post 2 and lamina tecti 1, negative pole post 3 and the lamina tecti 1, promoted top cap 100's structural stability.

In some examples, as shown in fig. 5-7, a first mating groove is formed on the first sub-injection-molded part 51, an upper surface of the first mating groove is arranged to protrude from an upper surface of the first sub-injection-molded part 51, the protruding portion can be matched with the positive post positioning groove 11, and the first mating groove is suitable for being matched with the positive post positioning plate 21, so that the first sub-injection-molded part 51 can be well clamped between the positive post positioning plate 21 and the top cover plate 1; form second cooperation groove on the sub-injection molding 52 of second, the sub-injection molding 52 upper surface setting of upper surface protrusion of second cooperation groove, the bulge can cooperate with negative pole post constant head tank 12, and second cooperation groove is suitable for and cooperates with negative pole post locating plate 31, from this, can be better with the sub-injection molding 52 centre gripping of second between negative pole post locating plate 31 and lamina tecti 1.

Optionally, the top cover 100 further comprises: an upper injection-molded part 6, the upper injection-molded part 6 including: anodal post injection molding 61 and negative pole post injection molding 62, as shown in fig. 1, fig. 3 and fig. 4, anodal post 2 and between 3 and the lamina tecti 1 are located respectively to anodal post injection molding 61 and negative pole post injection molding 62, thereby realize fixing positive utmost point post 2 and negative pole post 3 from week side, and pack at anodal post 2 and anodal post constant head tank 11, between 3 and the negative pole post constant head tank 12 of negative pole post, avoid anodal post 2 in anodal post

constant head tank

11, 3 rocks in negative pole post constant head tank 12 of negative pole post, and structural stability is high.

Further, the projection of positive post injection molding 61 coincides with the projection of positive post locating plate 21, the projection of negative pole post injection molding 62 coincides with the projection of negative pole post locating plate 31, that is to say, the shape of positive post injection molding 61 and the outline of positive post locating plate 21 is unanimous, the shape of negative pole post injection molding 62 and the outline of negative pole post locating plate 31 is unanimous, as shown in fig. 1 and fig. 5, the diameter on positive post injection molding 61 periphery edge is greater than the diameter of positive post locating slot 11, make positive post injection molding 61 can better joint in the upper end of positive post locating slot 11, and then the cooperation through positive post locating plate 21, make positive post 2 can be stable be in the central point of positive post locating slot 11, negative pole post injection molding 62 is structural the same as above, here no longer describe repeatedly.

Further, referring to fig. 8, a positive post positioning hole 611 allowing the positive post 2 to extend out is formed on the positive post injection molding piece 61, and a negative post positioning hole 621 allowing the negative post 3 to extend out is formed on the negative post injection molding piece 62, that is, through holes penetrating up and down are formed on both the positive post injection molding piece 61 and the negative post injection molding piece 62, so that the side of the positive post 2 extending out of the positive post positioning hole 611 and the side of the negative post 3 extending out of the negative post positioning hole 621 can be better connected with positive and negative connecting ends on an electric device or a charging device, so as to ensure normal charging and discharging operations of the lithium ion battery.

In a further example, as shown in fig. 5 and 9, a first limit groove 22 is formed in the middle of the positive post 2 in the vertical direction, and the first limit groove 22 is a groove recessed toward the axial direction on the outer circumferential wall of the positive post 2, as shown in fig. 8, a first limit table 612 engaged with the first limit groove 22 is formed on the positive post injection molded part 61, and the first limit table 612 is a protrusion protruding toward the axial direction on the inner circumferential wall of the positive post injection molded part 61, so that after the positive post 2 is installed in the positive post injection molded part 61, the first limit table 612 is located in the first limit groove 22, and the inner circumferential wall of the first limit groove 22 abuts against the outer circumferential wall of the first limit table 612, so that the first limit table 612 and the first limit groove 22 are fixedly connected. In other words, positive post 2 and positive post injection molding 61 are fixed connection to fixed distance between positive post locating plate 21 and the positive post injection molding 61, as shown in fig. 1 and fig. 5, can grasp top apron 1 and first sub-injection molding 51 that are located between positive post locating plate 21 and positive post injection molding 61 better from this, that is to say, make top apron 1, positive post 2, positive post injection molding 61 and first sub-injection molding 51 form fixed connection, and connection structure is ingenious, and structural strength is high.

In addition, the middle part of negative pole post 3 is formed with second spacing groove 32, second spacing groove 32 is the recess that is sunken towards the axis direction on the negative pole post 3 periphery wall, be formed with the spacing platform 622 of second with the spacing groove 32 complex on the negative pole post injection molding 62, the protruding towards the axis direction on the spacing platform 622 of second for negative pole post injection molding 62 internal perisporium, therefore, after negative pole post 3 installed in negative pole post injection molding 62, second spacing platform 622 is located second spacing groove 32, spacing inslot 32 internal perisporium of second and the peripheral wall butt of spacing platform 622 of second, that is to say, make and keep fixed connection between spacing platform 622 of second and the second spacing groove 32. In other words, negative pole 3 and negative pole injection molding 62 are fixedly connected to fix the distance between negative pole positioning plate 31 and negative pole injection molding 62, so that top cover plate 1 and second sub injection molding 52 between negative pole positioning plate 31 and negative pole injection molding 62 can be well clamped, that is, top cover plate 1, negative pole 3, negative pole injection molding 62 and second sub injection molding 52 form a fixed connection, the connection structure is ingenious, and the structural strength is high.

In still another example, the positive post 2 and the negative post 3 are both sleeved with the sealing rings 8, as shown in fig. 1 and 5, after the sealing rings 8 are assembled on the top cover 100, the sealing rings are located between the positive post positioning plate 21, the first sub-injection molding 51, the top cover plate 1 and the positive post injection molding 61, and between the negative post positioning plate 31, the second sub-injection molding 52, the top cover plate 1 and the negative post injection molding 62, so that the sealing rings 8 can be well filled in the gaps between the components to ensure the sealing performance of the connection positions of the positive post 2 and the negative post 3 with the top cover plate 1.

Other constructions and operations of the top cap 100 of the lithium ion battery according to the embodiment of the present invention are known to those of ordinary skill in the art and will not be described in detail herein.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A top cap for a lithium ion battery, comprising:

the top cover plate is provided with a positive pole column and a negative pole column which are arranged on the top cover plate;

the piece that converges, it locates to converge the piece the positive post with the lower extreme of negative pole post, it includes to converge the piece: the first sub-bus-bar piece, the second sub-bus-bar piece and the connecting piece are arranged between the first sub-bus-bar piece and the second sub-bus-bar piece, and the first sub-bus-bar piece and the second sub-bus-bar piece are respectively suitable for being matched with two electric core groups of the lithium ion battery.

2. The top cap of a lithium ion battery of claim 1, wherein the first sub-bus bar comprises:

the first electric connecting piece is suitable for being connected with a lug of one electric core group;

and one end of the first bending piece is connected with the middle part of the first electric connector, and the other end of the first bending piece extends upwards in an S-shaped bending mode and then extends towards the direction of the second sub-bus piece.

3. The top cap of a lithium ion battery of claim 2, wherein the second sub bus bar comprises:

the second electric connecting piece is suitable for being connected with the lug of the other electric core group;

and one end of the second bending piece is connected with the middle part of the second electric connecting piece, the other end of the second bending piece extends upwards in an S-shaped bending mode and then extends towards the direction of the first sub-collecting piece, and the first bending piece is not in contact with the second bending piece.

4. The top cap of a lithium ion battery according to claim 3,

first bending member orientation the upside face of the one end of second bending member has first inclined plane, the second bending member orientation the upside face of the one end of first bending member has the second inclined plane, the both ends of connecting piece be formed with respectively with first inclined plane with second inclined plane complex fitting surface.

5. The top cap of a lithium ion battery of claim 1, further comprising: a lower molding member, the lower molding member is located the lower extreme of lamina tecti, the lower molding member includes:

the anti-explosion valve comprises a first sub-injection molding part and a second sub-injection molding part, wherein the first sub-injection molding part and the second sub-injection molding part are spaced, a positioning groove corresponding to the anti-explosion valve is formed in one of the first sub-injection molding part and the second sub-injection molding part, and anti-explosion meshes are formed in the positioning groove.

6. The top cap of the lithium ion battery of claim 5, wherein the positive post is adapted to be die cast between the top cap plate and the first sub-injection molded part, and the negative post is adapted to be die cast between the top cap plate and the second sub-injection molded part.

7. The top cap of the lithium ion battery according to claim 1, wherein the top cap plate is formed with a positive post positioning groove and a negative post positioning groove, the positive post is formed with a positive post positioning plate engaged with the positive post positioning groove, and the negative post is formed with a negative post positioning plate engaged with the negative post positioning groove.

8. The top cap of a lithium ion battery of claim 7, further comprising: an upper injection molded part, the upper injection molded part comprising: positive post injection molding and negative pole post injection molding, the projection of positive post injection molding with the projection coincidence of positive post locating plate, the projection of negative pole post injection molding with the projection coincidence of negative pole post locating plate.

9. The top cap of the lithium ion battery according to claim 8, wherein the positive post injection molding part is formed with a positive post positioning hole for allowing the positive post to extend out, and the negative post injection molding part is formed with a negative post positioning hole for allowing the negative post to extend out.

10. The top cap of the lithium ion battery according to claim 8, wherein a first limiting groove is formed in the middle of the positive post, a second limiting groove is formed in the middle of the negative post, a first limiting table matched with the first limiting groove is formed on the positive post injection molding part, and a second limiting table matched with the second limiting groove is formed on the negative post injection molding part in the up-down direction.