CN222380803U

CN222380803U - Heavy current collector and polar column connection structure and battery

Info

Publication number: CN222380803U
Application number: CN202420761211.6U
Authority: CN
Inventors: 请求不公布姓名; 苏瑞; 付垚
Original assignee: Zhonggu Times Beijing New Energy Technology Co ltd
Current assignee: Zhonggu Times Beijing New Energy Technology Co ltd
Priority date: 2024-04-15
Filing date: 2024-04-15
Publication date: 2025-01-21
Anticipated expiration: 2034-04-15

Abstract

The utility model relates to the technical field of batteries, and particularly discloses a high-current collector and pole connection structure and a battery, wherein the connection structure comprises a second busbar and a first busbar, the second busbar comprises a busbar body II, a busbar body I and a connection edge which are integrally formed, an included angle is formed between the busbar body II and the busbar body I, and the first busbar comprises a busbar body III; the battery comprises a cover plate, a winding core and a shell, wherein the pole column on the cover plate is connected with current collectors at two ends of the winding core through the connecting structure. The utility model has strong overcurrent capability, less heat generated by overcurrent and compact structure, is beneficial to reducing the space volume ratio of inactive substances in the battery, improving the volume energy density and reducing the material cost.

Description

Heavy current collector and polar column connection structure and battery

Technical Field

The utility model relates to the technical field of batteries, in particular to a connection structure of a heavy current collector and a pole and a battery.

Background

With the development of new energy industry, the volume and capacity of battery products are inevitably developed, and the heating of the type of products in the use process is one of important factors affecting the performance of the products. Considering the overcurrent capability of the battery structural parts, reducing the heat generation in the electron transmission process through a sufficient overcurrent area is an effective countermeasure. In recent years, the capacity of lithium battery products has been increased, which means that the input and output current changes are larger and larger at the same multiplying power. In addition, the super capacitor product has high power output as a key characteristic, and the use of large current is also increased. In a battery with a full tab structure, the connection of a current collector and a tab becomes one of key links for limiting current output.

At present, the connection structure of the current collector and the pole of the main current all-pole cylindrical battery, capacitor and other devices in the market is shown in fig. 7, wherein the current collector and the bus bar I are welded by laser, and the bus bar I and the pole I are welded by rigid laser, so that the overall size is fixed. The connecting structure is limited to cylindrical battery products, the difficulty of turning over is high when the connecting structure is used for square battery products, and in addition, the copper raw material consumption is high, so that the product cost is increased. The bus bar II is of an integrated structure, and one end of the bus bar II is welded with the current collector through laser and the other end of the bus bar II is welded with the pole II through laser through multiple bending, so that the purpose of conducting current is achieved. However, the connecting structure has the defects that (1) the bus bar II is subjected to multiple bending operations, the winding core is extruded and is easy to break when being bent due to the fact that the force required by bending is increased, the thickness of the bus bar II is difficult to make thick, (2) the volume energy density of a battery core product is reduced due to the fact that the bus bar II is subjected to multiple bending round corners, and (3) the heat productivity of the product is increased due to the fact that the sectional area of the battery core is reduced due to the fact that the sectional area of the battery core is limited by overcurrent capability, and the performance of the battery core is affected.

The application aims to fundamentally solve the problem that the heat generated by connection among parts in the use process of a battery product affects the performance and the service life of the product because of the limitation of the battery product on large current output.

Disclosure of utility model

In view of the above-mentioned drawbacks of the prior art, the present utility model provides a connection structure of a high-current collector and a post, and a battery.

In order to achieve the above purpose, the main technical scheme adopted by the utility model comprises the following steps:

on the one hand, the utility model provides a connection structure of a heavy current collector and a pole, which is used for realizing connection of the pole and the collector in a battery, and comprises a second busbar and a first busbar, wherein the second busbar comprises a busbar body II, a busbar body I and a connecting edge which are integrally formed, an included angle is formed between the busbar body II and the busbar body I, the connecting edge is positioned at one end, opposite to the busbar body II, of the busbar body I, the first busbar comprises a busbar body III, the second busbar is connected with the pole through the connecting edge, the first busbar is connected with the collector, and the second busbar is connected with the first busbar through the busbar body II.

Preferably, the junction of busbar body II and busbar body I is provided with through-hole II, and through-hole I has been seted up at busbar body III's middle part.

Preferably, the thickness T of the second busbar is 0.2 mm.ltoreq.T.ltoreq.5 mm, preferably 0.5 mm.ltoreq.T.ltoreq.2.5 mm, more preferably 0.5 mm.ltoreq.T.ltoreq.1 mm.

Preferably, the external dimension and thickness of the first bus bar are consistent with the external dimension and thickness of the second bus bar.

Preferably, the connecting edge and the busbar body I are in arc transition, the included angle beta between the connecting edge and the busbar body I is 30 degrees < beta <150 degrees, preferably 45 degrees or more and less than or equal to 90 degrees, and the included angle alpha between the busbar body II and the busbar body I is 90 degrees < alpha <180 degrees, preferably 120 degrees or more and less than or equal to 150 degrees.

Preferably, the through hole II is a strip-shaped through hole, the strip-shaped through hole penetrates through the busbar body II and the busbar body I, and most of the strip-shaped through hole is positioned on the busbar body I.

Preferably, a strip-shaped groove is formed in the bus body III along the periphery of the through hole I.

On the other hand, the utility model provides a battery which comprises a cover plate, a winding core and a shell, wherein a pole is arranged on the cover plate, current collectors are exposed at two ends of the winding core, and the exposed current collectors are connected with the pole through the high-current collector and pole connecting structure.

Preferably, the shape of the winding core comprises any one of a cylinder, a square, a ring and a polygon, and when the winding core is cylindrical, the height H ₂ and the diameter D of the winding core meet the following relational expression that H ₂ is more than or equal to 60mm and less than or equal to 500mm and D is more than or equal to 30mm and less than or equal to 250mm.

Preferably, the height H ₁ of the current collector exposed by the winding core is less than or equal to 1mm and less than or equal to H ₁ and less than or equal to 20mm, and more preferably less than or equal to 5mm and less than or equal to H ₁ and less than or equal to 15mm.

According to the utility model, through the structural design and connection of the first bus bar and the second bus bar, the welding area of the current collector and the bus bar and the overcurrent sectional area of the bus bar are increased, so that the overcurrent capacity is enhanced, and the heat generated by overcurrent is reduced.

Compared with the prior art, the utility model has at least the following beneficial effects:

1. the overcurrent capacity is strong, the heat generated by the overcurrent is less, the heat generated by the battery on the structural connection is effectively reduced, and the power characteristic and the safety coefficient of the battery are improved;

2. The structure is compact, the occupied space is small, the space volume ratio of inactive substances in the battery is reduced, the volume energy density is improved, and the material cost is reduced;

3. The battery cell structure is suitable for battery cell structures with various shapes, not only removes the volume limitation of the battery cell, but also reduces the design difficulty of the battery cell, and is further beneficial to reducing the production cost.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a battery according to the present utility model;

Fig. 2 is a schematic structural diagram of a battery according to the present utility model;

FIG. 3 is a schematic view of the cover plate of FIGS. 1 and 2;

FIG. 4 is a schematic diagram of the second bus bar of FIGS. 1 and 2;

FIG. 5 is a schematic view of the first bus bar of FIGS. 1 and 2;

FIG. 6 is a schematic view of a connection structure of the cover plate, the second bus bar, and the first bus bar in FIGS. 1 and 2;

FIG. 7 is a diagram of a first conventional connection structure;

fig. 8 shows a second conventional connection structure.

In the figure, A1, bus bar I, A2, bus bar II, B1, pole I, B2, pole II, 1, cover plate, 11, cover plate body, 12, pole, 13, insulating layer, 14, liquid injection hole, 15, pressure release valve, 2, second bus bar, 21, bus bar body I, 22, bus bar body II, 23, connecting edge, 24, through hole II, 3, first bus bar, 31, bus bar body III, 32, through hole I, 33, bar-shaped groove, 4, winding core, 5 and shell.

Detailed Description

The technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The inventors of the present utility model have found in practice that the prior art for enhancing the overcurrent capability of battery components to reduce heat generation during use of the battery has the disadvantage that the improvement in overcurrent capability is limited at the expense of battery volumetric energy density and cell performance. The present utility model has been made in view of the above drawbacks.

As shown in the drawings 1 and 2, the utility model provides a battery, which comprises a cover plate 1, a winding core 4 and a shell 5, wherein the cover plate 1 specifically comprises a cover plate body 11, a pole 12, an insulating layer 13, a liquid injection hole 14 and a pressure release valve 15 (which are all of the prior art and are not described in detail) are arranged on the cover plate body 11, the winding core 4 comprises any one of a cylindrical shape, a square shape, an annular shape and a polygonal shape (the shape of the cover plate 1 is matched with the cylindrical shape), when the winding core 4 is cylindrical, the height H ₂ and the diameter D of the winding core 4 meet the following relational expression that H ₂ is less than or equal to 60mm and less than 500mm, D is less than or equal to 30mm and less than or equal to 250mm, current collectors are exposed at two ends of the winding core 4, the exposed current collector height H ₁ of the winding core 4 meets that H ₁ is less than or equal to 20mm, and the exposed current collectors are connected with the pole 12 through a large-current collector and pole connection structure.

It should be noted that:

(1) The current collector exposed from the winding core 4 is not too high or too low, which is not beneficial to the welding of the current collector and the bus bar, and influences the operability and the welding effect of the welding, and the too high material waste and the increased cost are caused, and the practice of the inventor proves that the exposed current collector is preferably positioned between 1mm and 20mm, and the height of the exposed current collector is preferably 5mm to 15 mm. In the height range, the winding core 4 of the full tab can obtain a larger welding area, and the overcurrent capacity of the whole charging and discharging process is ensured.

(2) The connection is preferably laser welding, and the current collector exposed from the pole 12 and the winding core 4 and the connection structure of the heavy current collector and the pole are preferably made of the same material, including but not limited to copper, aluminum, etc.

(3) The inventor obtains through creative work that when the height H ₂ and the diameter D of the winding core 4 meet the following relational expression that H ₂ is less than or equal to 60mm and less than or equal to 500mm, D is less than or equal to 30mm and less than or equal to 250mm, the battery can obtain the maximized capacity in a limited space, has stable structure and is not easy to deform or damage, heat accumulation can be effectively reduced, and the safety of the battery is improved.

Further, as shown in fig. 4, 5 and 6, the connection structure of the heavy current collector and the pole includes a second busbar 2 and a first busbar 3, the second busbar 2 includes a busbar body II22, a busbar body I21 and a connection edge 23 integrally formed, an included angle is formed between the busbar body II22 and the busbar body I21, the connection edge 23 is located at an end of the busbar body I21 opposite to the busbar body II22, the first busbar 3 includes a busbar body III31, the second busbar 2 is connected to the pole 12 through the connection edge 23, the first busbar 3 is connected to the exposed current collector on the winding core 4, the second busbar 2 is connected to the first busbar 3 through the busbar body II22, and through holes are correspondingly formed at positions of the second busbar 2 and the first busbar 3 opposite to the injection hole 14 for performing an injection operation (not shown).

The coil core 4 is formed by laminating a positive electrode, a negative electrode and a diaphragm, then shaping foil materials exposed at two ends of the coil core 4, compacting and compacting the foil material layers, then welding the foil materials with a first busbar 3 through laser of the same material, adjusting welding tracks on the first busbar 3 to enable the overflow area to meet the design requirement, welding the pole column 12 with a second busbar 2 through laser of the same material, adjusting welding tracks on the second busbar 2 to enable the second busbar 2 to be fused with the pole column 12 and enable the overflow area to meet the design requirement, and enabling a busbar body II22 of the second busbar 2 to be in plane contact with the first busbar 3 and enable the same materials of the second busbar 2 to be fused together through laser welding to achieve the set overflow area.

The current collectors exposed at the two ends of the winding core 4 are connected with the outside of the winding core 4 through the switching of the first bus bar 3 and the second bus bar 2. The design structure for switching the two buses is small in occupied space and does not involve repeated bending of the buses, so that the buses are designed to have a certain thickness on the premise of considering overcurrent capacity, the first buses 3 and the second buses 2 are welded in a plane-to-plane mode, the welding area is obviously increased, the overcurrent capacity of the whole charging and discharging process is guaranteed, and therefore heat generation quantity caused by transmission of electrons by conductors in the using process of products can be reduced. In addition, the overall dimension and thickness of the second bus bar 2 and the first bus bar 3 can be the same or different, and the design structure of the two bus bar switching is free of requirements on the shape of the battery core and has no limitation on the volume of the battery core, so that the design difficulty of the battery core is reduced.

As a preferred embodiment of the present utility model, the thickness T of the second busbar 2 satisfies that T is 0.2 mm.ltoreq.5 mm, preferably 0.5 mm.ltoreq.T.ltoreq.2.5 mm, more preferably 0.5 mm.ltoreq.T.ltoreq.1 mm.

Thicker busbar has bigger cross-sectional area, can hold more electric current and pass through, therefore has higher overcurrent capacity, and heat dispersion is good, mechanical strength and stability are high, can guarantee the safe, the stable use of battery. However, too thick a bus bar may result in an increase in weight and cost of the battery. In comprehensive consideration, in order to achieve good overcurrent capability and to achieve the balance between the weight and the cost of the battery, the thickness T of the second busbar 2 is preferably 0.2mm or less and 5mm or less, more preferably 0.5mm or less and 2.5mm or less, and even more preferably 0.5mm or less and 1mm or less.

In another preferred embodiment of the present utility model, the external dimension and thickness of the first busbar 3 are identical to the external dimension and thickness of the second busbar 2, and the external dimension of the first busbar 3 is identical to the external dimension of the second busbar 2, so as to help to maintain the stability of the battery structure, and the thicknesses of the first busbar 3 and the second busbar 2 are both between 0.2mm and 5mm and are identical, so as to help to obtain better overcurrent capability.

As a preferred embodiment of the present utility model, the connecting edge 23 and the busbar body I21 are in arc transition, the included angle beta between the connecting edge 23 and the busbar body I21 satisfies 30 DEG < beta <150 DEG, preferably 45 DEG beta < 90 DEG, and the included angle alpha between the busbar body II22 and the busbar body I21 satisfies 90 DEG < alpha <180 DEG, preferably 120 DEG alpha <150 deg.

When the cover plate 1 completely seals the housing 5, the cover plate 1 is parallel to the first busbar 3, and at this time, the included angle between the cover plate 1 and the busbar body I21 is the same as the included angle between the busbar body I21 and the busbar body II22, and both the included angles are obtuse angles. Although the second busbar 2 has good elasticity and toughness, considering that it has a certain thickness to ensure a certain overcurrent capability, the too large bending degree can easily occupy a larger space and also cause tearing, so the included angle β between the connecting edge 23 and the busbar body I21 and the included angle α between the busbar body II22 and the busbar body I21 are preferably obtuse angles, so the deformation of the second busbar 2 in the packaging process of the cover plate 1 can be reduced as much as possible, and the second busbar is convenient to have a relatively thicker thickness.

The above embodiment is applicable to a coreless winding core, and when used for a cored winding core, the junction of the busbar body II22 and the busbar body I21 is provided with a through hole II24 for the core rod to pass through, and the middle part of the busbar body III31 is provided with a through hole I32. In order not to influence the upset of apron 1, through-hole II24 is the bar through-hole, bar through-hole link up busbar body II22 and busbar body I21, and bar through-hole mostly is located busbar body I21, and when apron 1 overturns, the plug can pass in the bar through-hole in a flexible way and pass out. The first busbar 3 is arranged on the core rod in a penetrating way through the through hole I32 and is welded with current collectors exposed at two ends of the winding core 4 through laser of the same material.

As a preferred implementation method, in still another embodiment of the present utility model, on the busbar body III31, specifically, the surface of the busbar body III31 facing the cover plate 1 is provided with a strip-shaped groove 33 along the periphery of the through hole I32, and when the busbar body III31 is circular, the strip-shaped groove 33 is preferably arranged along the radial direction of the circular shape, and through a plurality of strip-shaped grooves 33, the electrolyte can be conveniently infiltrated, and the electrolyte infiltration time can be shortened. Of course, the strip-shaped groove 33 may be formed as an opening having other shapes, such as a circle, an ellipse, an arc, etc., and the present utility model is not limited thereto.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that alterations, modifications, substitutions and variations may be made in the above embodiments by those skilled in the art without departing from the scope of the utility model. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Claims

1. A high-current current collector and pole connection structure, used to achieve the connection between the pole and the current collector in a battery, characterized in that it comprises: a second busbar (2) and a first busbar (3);

The second busbar (2) comprises: a busbar body II (22), a busbar body I (21) and a connecting edge (23) which are integrally formed, wherein the busbar body II (22) and the busbar body I (21) form an angle, and the connecting edge (23) is located at an end of the busbar body I (21) opposite to the busbar body II (22);

The first busbar (3) comprises a busbar body III (31);

The second busbar (2) is connected to the pole via a connecting edge (23), the first busbar (3) is connected to the current collector, and the second busbar (2) is connected to the first busbar (3) via a busbar body II (22).

2. The high current collector and pole connection structure according to claim 1 is characterized in that a through hole II (24) is provided at the connection between the bus body II (22) and the bus body I (21), and a through hole I (32) is provided in the middle of the bus body III (31).

3. The high-current current collector and pole connection structure according to claim 1 or 2, characterized in that the thickness T of the second busbar (2) satisfies: 0.2 mm ≤ T ≤ 5 mm.

4. The high-current current collector and pole connection structure according to claim 3, characterized in that the outer dimensions and thickness of the first busbar (3) are consistent with the outer dimensions and thickness of the second busbar (2).

5. The high-current collector and pole connection structure according to claim 1 or 2 is characterized in that a circular arc transition is formed between the connecting edge (23) and the busbar body I (21), and an angle β between the connecting edge (23) and the busbar body I (21) satisfies: 30°＜β＜150°; an angle α between the busbar body II (22) and the busbar body I (21) satisfies: 90°＜α＜180°.

6. The high current collector and pole connection structure according to claim 2 is characterized in that the through hole II (24) is a strip-shaped through hole, which passes through the bus body II (22) and the bus body I (21), and most of the strip-shaped through hole is located on the bus body I (21).

7. The high current collector and pole connection structure according to claim 2, characterized in that a strip-shaped groove (33) is provided on the busbar body III (31) along the outer periphery of the through hole I (32).

8. A battery, comprising: a cover plate (1), a winding core (4) and a shell (5), wherein a pole (12) is arranged on the cover plate (1), and current collectors are exposed at both ends of the winding core (4), characterized in that the exposed current collector is connected to the pole (12) through a large current collector and pole connection structure as described in any one of claims 1 to 7.

9. The battery according to claim 8, characterized in that: the shape of the winding core (4) includes: any one of cylindrical, square, annular, and polygonal; when the winding core (4) is cylindrical, its height _H2 and diameter D satisfy the following relationship: _{60mm≤H2≤500mm} , 30mm≤D≤250mm.

10. The battery according to claim 8, characterized in that a height _H1 of the current collector exposed from the winding core (4) satisfies: 1 mm ≤ _H1 ≤ 20 mm.