Wide tab energy storage device

Abstract

The utility model discloses a wide-tab energy storage device, which comprises a top cover provided with poles with opposite electric polarities; the core package is provided with tabs with opposite electric polarities; the metal shell is used for accommodating the core package and mounting the top cover; the confluence assembly is used for connecting the pole and the tab; the confluence assembly comprises a pole connecting part and a tab connecting part, notches are formed in the arc R angle positions of the two ends of the tab, the tab connecting part is arranged in the notches, and the pole connecting part is connected with the pole. The pole is of a sheet-shaped structure, and the area of the cross section of one pole is 1-15 times of the area of the cross section of the tab connected with the pole. The bottom of the notch is arc-shaped. The depth of the notch is greater than the width of the tab connecting part, so that the tab connecting part is wrapped in the tab. A top cover insulating layer is arranged on the inner side of the top cover, a notch for mounting the pole is formed in the top cover insulating layer, and the thickness of the top cover insulating layer is larger than that of the pole connecting part. The problems that an existing energy storage device is high in cost, low in safety, short in service life and poor in heat dissipation effect are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery structures, in particular to a wide-tab energy storage device. Background Art

[0002] The high-rate charge-discharge performance scenarios formed during rapid charging or random overtaking and acceleration have led to increasingly higher thermal safety requirements for the cross-sectional area of ​​the electrical connection of the chemical energy storage device and heat dissipation during the charge-discharge process. The Chinese patent with announcement number CN107369853B discloses an electrochemical energy storage device, which provides a full-tab core package or battery cell structure, but is not friendly to the existing tab and battery cell bus connection.

[0003] Existing winding core packages have deformed and bulged tabs, or the busbars use complex special-shaped structures to match the core package tabs, which brings challenges to the existing busbar assembly process technology and equipment. In large-capacity energy storage, such as when the tabs of a multi-core package are electrically connected to a busbar assembly, there is a risk that only one side of the tab of the core package is connected to the transition electrical connection. Because after the parallel-arranged, multi-layer transition electrical connections are inserted into the hollow position of the winding core of the multi-core package tabs, the tabs on the inner side of the multi-core package cannot form an effective connection with the transition electrical connection or are difficult to connect, and the advantage of wide tabs that meet high-rate charging and discharging cannot be reflected; furthermore, the special-shaped, transposed busbar setting also has problems such as complex connection structure and low utilization of battery cell margin space. Utility Model Content

[0004] The utility model aims to provide a wide-tab energy storage device to solve the problems of high cost, low safety, short life and poor heat dissipation effect of existing energy storage devices.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solution: a wide-tab energy storage device, comprising:

[0006] The top cover is provided with poles with opposite electrical polarities; including a positive pole and a negative pole. If there is one top cover, the positive pole and the negative pole are located on the same top cover. If there are two top covers, the positive pole is arranged on one top cover, and the negative pole is arranged on the other top cover.

[0007] The core package has pole ears with opposite electrical polarities; the corresponding pole ears include a positive pole ear and a negative pole ear, which are connected to the pole column, and the core package is wound or laminated.

[0008] The metal shell is used to accommodate the core package and install the top cover. It is an aluminum shell or a stainless steel shell structure and can be integrally formed or welded.

[0009] Busbar assembly, used to connect poles and lugs.

[0010] Process notches are provided at the R - corner positions of both ends of the tab, which can ensure that the flatness of the tab at the R - corner position is the same as that of the tab at the non - R - corner position during subsequent pretreatment. The busbar assembly includes a pole connection part and a tab connection part. The tab connection part is arranged in the notch, and the pole connection part is connected to the pole. Different from the single - side contact in the prior art, the tab connection part of the present utility model is arranged between the tabs, which can meet the requirements of over - current charging and discharging and heat dissipation.

[0011] Preferably, the bottom of the notch has a circular arc feature. This can prevent damage to the non - tab part of the core package during the subsequent processes such as prefabricating the process notch of the tab and tab pretreatment.

[0012] Preferably, the pole is in a sheet structure, and the cross - sectional area of one pole is 1 - 15 times that of the tab connected to it.

[0013] Preferably, the depth of the notch is greater than the width of the tab connection part, so that the tab connection part is wrapped in the tab. This can reduce the volume ratio of the busbar assembly in the energy storage device.

[0014] Preferably, a top - cover insulation layer is provided on the inner side of the top cover. A notch for pole installation is provided on the top - cover insulation layer, and the thickness of the top - cover insulation layer is greater than the thickness of the pole connection part. To improve the physical insulation between the busbar assembly, the pole connection part and the core package. The shape of the notch reserved on the top - cover insulation layer can be a quadrilateral, a circle, a combination of an arc and a polygon, etc., so as to better match the shapes of the busbar assembly and the pole connection part; the width and length dimensions of the top - cover insulation layer corresponding to the pole are 0.1 mm larger than the corresponding geometric dimensions of the busbar assembly and the pole connection part to ensure the assembly and cooperation of the busbar assembly, the pole connection part and the top - cover pole.

[0015] Preferably, the tab connection part and the tab are welded into one body, and the welding area is at least 3 times the sum of the cross - sectional areas of the thicknesses of the tabs on the same side. This can further meet the over - current charging and discharging and heat dissipation performance of the core package.

[0016] Preferably, the pole connection part is welded to the pole, and the welding area is larger than the sum of the welding areas of the tab connection part and the tab on the same side.

[0017] The two tab connection parts and the pole connection part are arranged at 90°, ensuring that multiple core packages are mutually attached in the large - area direction. The tabs are bundled with tape. Ensuring that multiple core packages are mutually attached tightly in the large - area direction without rebound.

[0018] An insulation protection layer for the core package is provided outside the core package to isolate the metal shell and the core package. The thickness of the insulation protection layer for the core package should be as thin as possible, such as 0.1 mm thick. After the top cover, the core package, the core package tab and the busbar assembly wrapped with the insulation protection layer for the core package are integrally put into the shell, the busbar assembly, the tab and the shell can be in contact as much as possible to achieve heat conduction and reduce the temperature rise of the battery cell during charge and discharge.

[0019] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0020] For the wide-tab energy storage device of the present utility model, the core package tab only needs to be cut at the winding R corner position, and the amount of pole piece cutting is small, resulting in less die cutting of the pole piece; the busbar assembly has a simple structure, especially the electrical connection part with the core package tab has straight and flat plate features, and can be directly punched and obtained on the rolled sheet, with a simple manufacturing process and wide sources; the core package tab does not need to be pre-welded and shaped, but directly wraps the busbar assembly and is welded into a core package stack, shortening and simplifying the core package manufacturing process.

[0021] For the wide-tab energy storage device of the present utility model, in the height direction of the energy storage device, the top cover and the shell are simultaneously in close contact with the R corner of the core package winding, which can restrain the positive and negative pole pieces at the R position of the core package, reduce the expansion amount of the positive and negative pole pieces at the R position of the core package, and reduce the side reactions of the energy storage device, such as reducing the risk of lithium precipitation on the R corner diaphragm and the negative pole piece of the lithium-ion battery.

[0022] For the wide-tab energy storage device of the present utility model, the connection surfaces of the positive and negative pole columns and the busbar assembly tab with the core package are large, which can effectively achieve overcurrent and heat dissipation, and achieve the purpose of extending the battery life. Description of the Drawings

[0023] Figure 1 It is a schematic side structure diagram of the wide-tab energy storage device of the present utility model;

[0024] Figure 2 It is a schematic top-side structure diagram of the wide-tab energy storage device of the present utility model;

[0025] Figure 3 It is a schematic connection structure diagram of the tab, the core package and the busbar assembly of the present utility model;

[0026] Figure 4 It is a schematic inner side structure diagram of the top cover of the present utility model;

[0027] Figure 5 It is a schematic outer side structure diagram of the top cover of the present utility model;

[0028] Figure 6 It is a schematic diagram of the busbar assembly structure of the present utility model (one);

[0029] Figure 7 It is a schematic diagram of the busbar assembly structure of the present utility model (two);

[0030] Figure 8 Schematic diagram of the core package structure of the present utility model;

[0031] Figure 9 Schematic diagram of the assembly structure of the busbar assembly and the tab of the present utility model;

[0032] Figure 10 Schematic diagram of the connection structure between the busbar assembly and the tab of the present utility model;

[0033] Figure 11 Schematic diagram of the combined structure of the busbar assembly and the terminal post of the present utility model;

[0034] Figure 12 Schematic diagram of the structure after the 90° bending of the connection part between the terminal post and the tab connection part of the present utility model.

[0035] Reference numerals: 1, top cover; 101, terminal post; 102, liquid injection hole; 103, explosion-proof pressure relief valve; 104, top cover insulating layer; 2, metal shell; 3, core package; 301, tab; 4, core package insulating protection layer; 5, busbar assembly; 501, terminal post connection part; 502, tab connection part; 6, welding equipment; 3011, process notch. Detailed implementation manners

[0036] In order to make the technical means, creative features, achieved purposes and functions of the present utility model easy to understand, the present utility model will be further described below in conjunction with specific implementation manners.

[0037] In the description of the present utility model, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0038] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] As Figures 1 to 3 shown, the wide tab energy storage device of this embodiment includes:

[0041] A top cover 1, provided with pole columns 101 with opposite polarities; a liquid injection hole 102 and an explosion-proof pressure relief valve 103 are also provided on the top cover 1.

[0042] A core package 3, which is a wound core package and has tab ears 301 with opposite polarities;

[0043] A metal shell 2, used to accommodate the core package 3 and install the top cover 1;

[0044] A busbar assembly 5, used to connect the pole column 101 and the tab ear 301;

[0045] The busbar assembly 5 includes a pole column connection part 501 and a tab ear connection part 502. Notches 3011 are provided at the arc R angle positions at both ends of the tab ear 301, and the tab ear connection part 502 is arranged in the notches 3011, and the pole column connection part 501 is connected to the pole column 101.

[0046] As Figure 4 and 5 shown, to cooperate with the busbar assembly 5 and the core package 3 to develop a top cover, vacancies are reserved at the corresponding positions of the positive and negative pole columns on the top cover insulating layer 104 facing the core package 3, so that the pole column connection part 501 is electrically connected to the top cover pole column 101; the thickness of the top cover insulating layer 104 is 0.01 - 0.15 mm larger than the thickness of the pole column connection part 501; when the top cover 1 is directly attached to the winding R angle of the core package 3, there is an insulating gap between the pole column connection part 501 and the core package 3 to improve the physical insulation between the busbar assembly and the core package; at the positive and negative pole columns of the top cover 1 facing the core package 3, the shape of the reserved top cover insulating layer 104 can be a quadrilateral, a circle, a combination of an arc and a polygon, etc., so as to better cooperate with the shape of the pole column connection part 501; the width and length dimensions of the top cover insulating layer 104 corresponding to the pole column 101 are 0.05 - 0.1 mm larger than the corresponding geometric dimensions of the pole column connection part 501 to ensure the assembly and cooperation between the pole column connection part 501 and the pole column 101.

[0047] As Figure 6 and 7 shown, for two different busbar assembly structures, the pole column connection part 501 can be set as a T shape, a cross shape or an arc shape.

[0048] As Figure 8 shown, the width of the tab 301 of the core package 3 of the winding structure has the same or similar dimensions as the width of the core package to meet the design goal of a wide-width tab energy storage device. Process notches 3011 are prefabricated at the four arc R-corner positions of the core package winding to ensure that the tabs at the arc R-corner positions can maintain the same flatness as the tabs at the non-arc R-corner positions during subsequent pretreatment; the bottom of the process notch 3011 has an arc feature to prevent damage to the non-tab part of the core package 3 during subsequent processes such as in the process notch 3011 and the pretreatment of the tab 301.

[0049] As Figures 9 to 11 shown, pass the tab connection part 502 of the busbar assembly 5 through the process notch 3011 to ensure that the tab connection part 502 is always covered by the tab 301 which is divided into two parts by the process notch 3011; the width of the tab connection part 502 is 0 - 2 mm narrower than that of the tab 301 to ensure that the tab connection part 502 is hidden in the tab 301, thereby reducing the volume ratio of the busbar assembly 5 in the energy storage device; place the tab 301 covering the tab connection part 502 at the predetermined position of the welding equipment 6, and weld the tab connection part 502 and the core package tab 301 into one body by an ultrasonic welding equipment, etc. The welding area is at least 3 times the total cross-sectional area of the thickness of the tab 301 on the same side to meet the over-current and heat dissipation requirements of the core package during charging and discharging.

[0050] To match the shape of the pole connection part 501 and the preset ultimate charge and discharge capacity of the energy storage mechanism, the cross-sectional area of the positive and negative pole columns of the top cover is 1 - 15 times the total cross-sectional area of the core package tabs 301 in the energy storage device. The positive and negative pole columns can be distributed on both sides of the same top cover at the same time, or are respectively arranged at specific positions on two top covers to meet the structural requirements of the energy storage device with the positive and negative pole columns distributed on different sides.

[0051] Place the core package stack with multiple welded busbar assemblies and core package tabs on the side of the top cover facing the core package, and ensure that the pole connection part 501 fits with the pole 101 of the top cover facing the core package side; under the action of the laser welding system, the pole connection part 501 and the pole 101 of the top cover facing the core package side are tightly welded together; the welding connection area between the pole connection part 501 and the pole 101 of the top cover facing the core package side is 1 - 2 times the total value of the welding area between the busbar assembly and the tab on the same side.

[0052] As Figure 12 shown, after the busbar assembly is welded to the top cover pole, then bend the core package and the busbar assembly by 90° along the connection between the busbar assemblies 501 and 502 to ensure that multiple core packages fit together in the large-area direction; attach bundling tapes with the thickness of the core package on the tab 301 directions on both sides to ensure that multiple core packages fit tightly together in the large-area direction without rebound.

[0053] As Figure 1 and 2As shown, the core package 3 and the top cover 1 are covered by the core package insulation protection layer 4 as a whole, so as to be placed into the metal shell 2 and form the insulation protection between the core package 3 and the metal shell 2; the core package insulation protection layer 4 is connected to the top cover insulation protection layer 104 to realize the integration of the aforementioned top cover 1 and the core package 3; the periphery of the core package insulation protection layer 4 and the top cover insulation protection layer 104 is formed with multiple-point connections by hot melting to cover the inner wall of the top cover facing the core package side, the core package tab, the busbar assembly and the core package stack core package body; the thickness of the core package insulation protection layer 4 is as thin as possible, such as 0.01 - 0.1 mm thick; after the top cover, the core package, the core package tab and the busbar assembly covered with the core package insulation protection layer are integrally put into the shell, the busbar assembly and the tab can be in contact with the shell as much as possible to realize heat conduction and reduce the temperature rise amplitude of the battery cell during charge and discharge.

[0054] For the wide-tab energy storage device of this embodiment, the amount of pole piece cutting is small, the processing process is reduced, the processing cost can be controlled, the busbar assembly has a simple structure, especially the electrical connection part with the core package tab has straight and flat characteristics, and can be directly punched and obtained on the rolled sheet. The manufacturing process is simple, the source is wide, the tab does not need to be pre-welded and shaped, but directly covers the busbar assembly and is welded into the core package stack, shortening and simplifying the core package manufacturing process.

[0055] For the wide-tab energy storage device of this embodiment, the connection surfaces of the positive and negative electrode posts and the busbar assembly tab with the core package are large, which can effectively realize overcurrent and heat dissipation, and achieve the purpose of extending the battery life.

[0056] The above are only the embodiments of the present invention, and common knowledge such as specific structures and characteristics well known in the art are not described in detail here. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A wide tab energy storage device, comprising: A top cover (1) is provided with poles (101) with opposite electrical polarities; The core package (3) has pole ears (301) with opposite electrical polarities; A metal shell (2) for accommodating the core package (3) and installing the top cover (1); A busbar assembly (5) for connecting a pole (101) and a pole lug (301); The feature is that the busbar assembly (5) comprises a pole connecting portion (501) and a pole lug connecting portion (502), process notches (3011) are provided at the arc R angle positions at both ends of the pole lug (301), the pole lug connecting portion (502) is arranged in the process notch (3011), and the pole connecting portion (501) is connected to the pole (101).

2. The wide tab energy storage device according to claim 1, characterized in that: The pole (101) is a sheet-like structure, and the cross-sectional area of ​​one pole (101) is 1 to 15 times the cross-sectional area of ​​the pole lug (301) connected thereto.

3. The wide tab energy storage device according to claim 1, characterized in that: The bottom of the notch (3011) is arc-shaped.

4. The wide tab energy storage device according to claim 1, characterized in that: The depth of the notch (3011) is greater than the width of the pole lug connecting portion (502), so that the pole lug connecting portion (502) is wrapped inside the pole lug (301).

5. The wide tab energy storage device according to claim 1, characterized in that: A top cover insulating layer (104) is provided on the inner side of the top cover (1), a notch for installing the pole (101) is provided on the top cover insulating layer (104), and the thickness of the top cover insulating layer (104) is greater than the thickness of the pole connecting portion (501).

6. The wide tab energy storage device according to any one of claims 1 to 5, characterized in that: There are one or two top covers (1), and the two poles (101) are arranged on one side of the top cover (1) or the two poles are arranged on two top covers (1) respectively.

7. The wide tab energy storage device according to claim 5, characterized in that: The pole lug connection portion (502) and the pole lug (301) are welded into one body, and the welding area is at least three times the sum of the thickness and cross-sectional areas of the pole lug (301) on the same side.

8. The wide tab energy storage device according to claim 5, characterized in that: The pole connection portion (501) is welded to the pole (101), and the welding area is larger than the sum of the welding areas of the pole lug connection portion (502) and the pole lug (301) on the same side.

9. The wide tab energy storage device according to claim 5, characterized in that: The two pole lug connecting portions (502) and the pole column connecting portion (501) are arranged at 90 degrees, and the pole lug (301) is bound with adhesive tape.

10. The wide tab energy storage device according to claim 5, characterized in that: A core package insulating protective layer (4) is provided outside the core package (3) and is used to isolate the metal shell (2) and the core package (3).

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