Zipper type die-cutting multi-tab structure of solid-state battery

Abstract

The utility model discloses a zipper type die cutting multi-tab structure of a solid-state battery, which comprises a solid-state battery lamination group, a current collector and a leading-out structure, the solid-state battery lamination group comprises a positive plate and a negative plate, the current collector comprises a positive die cutting current collector led out from the positive plate and a negative die cutting current collector led out from the negative plate, and the leading-out structure is arranged between the positive die cutting current collector and the negative die cutting current collector. The positive die-cutting current collector and the negative die-cutting current collector are arranged adjacently; the number of the positive die-cutting current collectors is at least two, the number of the negative die-cutting current collectors is at least two, the lead-out structure comprises a negative lead-out sheet and a positive lead-out sheet, the negative lead-out sheet is connected with the multiple negative die-cutting current collectors, the positive lead-out sheet is connected with the multiple positive die-cutting current collectors, and the negative lead-out sheet is connected with the multiple negative die-cutting current collectors. And the negative electrode lead-out sheet and the positive electrode lead-out sheet are positioned on the same side. In the high-rate discharge process of the solid-state laminated battery, the travel of electrons on a reaction interface passing through the current collector is shorter, so that the physical impedance of electrons passing through the battery is reduced, and the performance indexes such as the capacity, the charging efficiency and the cycle life of the battery are improved.

Description

Technical Field

[0001] The utility model relates to the field of batteries, and particularly to a zipper-type die-cut multi-tab structure for a solid-state battery. Background Art

[0002] Tabs are metal conductors that lead out the positive and negative electrodes in a battery cell and are the contact points during battery charging and discharging. A full-tab battery is a new type of battery that uses a full-tab structure for connection and current conduction. The battery cell electrode sheet and the current collector plate are connected by laser technology, so that the over-current capacity between the electrode sheet and the cover plate is not lower than that of the electrode sheet itself, thereby greatly improving the over-current capacity of the battery, reducing the heat generation of the battery, and breaking through the bottleneck that cylindrical batteries are difficult to make larger.

[0003] The realization of the full-tab process also brings the characteristics of inclusiveness to cylindrical batteries. Especially for many current popular battery technology innovations, such as: making the cylindrical volume larger, achieving vehicle-level integration, being compatible with the dry electrode coating process, and applying various innovative materials (high-nickel, cobalt-free positive electrodes, silicon-based negative electrodes, etc.), all can be fully compatible under the full-tab platform.

[0004] Currently, the current collectors commonly used in commercial lithium-ion batteries are Al foils and Cu foils. The positive and negative active materials form a two-dimensional film on the surface of the current collector through a coating process. There is only limited interfacial contact between the current collector and the active material film. Therefore, the contact impedance is relatively large, which easily becomes a limiting factor for the rate performance of lithium-ion batteries.

[0005] The current collector is an important component inside a lithium-ion battery. Electrons in the positive and negative active materials enter the external circuit through the current collector and finally return to the active materials on the other side.

[0006] The existing technical solutions are mainly as follows: The battery with a stacked and co-directional tab structure leads out the die-cut current collector from one side of the positive electrode sheet / negative electrode sheet.

[0007] Among them, leading out the current collector tab from one side increases the travel distance of electrons through the current collector during the high-rate discharge process of the battery, increasing the physical impedance inside the battery. Utility Model Content

[0008] The main purpose of the present utility model is to propose a zipper-type die-cut multi-tab structure for a solid-state battery, aiming to adopt a new solution to shorten the travel distance of electrons through the current collector at the reaction interface during the high-rate discharge process of the solid-state stacked battery, reduce the physical impedance of electrons passing through inside the battery, improve performance indicators such as the capacity, charging efficiency, and cycle life of the battery, which is of great significance for the application of electric vehicles.

[0009] To achieve the above object, the present utility model proposes a zipper-type die-cut multi-tab structure for a solid-state battery, including:

[0010] A solid-state battery stack, the solid-state battery stack comprising a positive electrode sheet and a negative electrode sheet;

[0011] Current collector (i.e., the current collector is integrally die-cut from the electrode sheet), the current collector includes a positive electrode die-cut current collector led out from the positive electrode sheet and a negative electrode die-cut current collector led out from the negative electrode sheet, the positive electrode die-cut current collector and the negative electrode die-cut current collector are arranged adjacent to each other;

[0012] The positive electrode die-cut current collector and the negative electrode die-cut current collector are provided with at least two each;

[0013] The lead-out structure includes a negative electrode lead-out sheet and a positive electrode lead-out sheet, wherein the negative electrode lead-out sheet is connected to a plurality of negative electrode die-cut current collectors, and the positive electrode lead-out sheet is connected to a plurality of positive electrode die-cut current collectors,

[0014] The negative electrode lead-out sheet and the positive electrode lead-out sheet are located on the same side.

[0015] Firstly, a plurality of positive electrode die-cut current collectors and negative electrode die-cut current collectors are arranged adjacent to each other, so that the positive electrode die-cut current collectors and the negative electrode die-cut current collectors are arranged in a cross-zipper-like manner, that is, staggered cross-distribution; and the negative electrode lead-out sheet and the positive electrode lead-out sheet are located on the same side;

[0016] When the solid-state laminated battery is discharged at a high rate, the electrons at the reaction interface have a shorter journey through the current collector, thereby reducing the physical impedance of the electrons passing through the battery, and improving the battery's performance indicators such as capacity, charging efficiency and cycle life.

[0017] The current collector refers to the structure or component that collects current. The battery current collector also generally includes the tabs, which are metal conductors that lead the positive and negative electrodes from the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the utility model;

[0019] Figure 2 A schematic diagram of the cooperation between the positive electrode sheet and the positive electrode die-cut current collector;

[0020] Figure 3 Schematic diagram of the coordination between the negative electrode sheet and the negative electrode die-cut current collector.

[0021] In the figure,

[0022] 1 is a solid-state battery stack, 11 is a positive electrode, 12 is a negative electrode,

[0023] 2 is the die-cut current collector for the positive electrode, 22 is the die-cut current collector for the negative electrode,

[0024] 31 is the positive electrode lead-out plate, and 32 is the negative electrode lead-out plate. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0026] It should be noted that if there are directional indications (such as up, down, left, right, front, back, top, bottom, inside, outside, vertical, horizontal, longitudinal, counterclockwise, clockwise, circumferential, radial, axial...) involved in the embodiments of the present utility model, then such directional indications are only used to explain the relative positional relationship and movement conditions between components in a certain specific posture (as shown in the accompanying drawings). If this specific posture changes, then such directional indications will also change accordingly.

[0027] In addition, if there are descriptions involving "first" or "second" in the embodiments of the present utility model, then such descriptions of "first" or "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present utility model.

[0028] As Figures 1 to 3 shown, a zipper-type die-cut multi-tab structure of a solid-state battery includes:

[0029] A solid-state battery stack 1, and the solid-state battery stack 1 includes a positive electrode sheet 11 and a negative electrode sheet 12;

[0030] A current collector (i.e., the current collector is integrally die-cut from the electrode sheet), and the current collector includes a positive electrode die-cut current collector 2 led out from the positive electrode sheet 11 and a negative electrode die-cut current collector 22 led out from the negative electrode sheet 12, and the positive electrode die-cut current collector 2 and the negative electrode die-cut current collector 22 are arranged adjacent to each other;

[0031] At least two of the positive electrode die-cut current collector 2 and the negative electrode die-cut current collector 22 are respectively provided;

[0032] A lead-out structure, and the lead-out structure includes a negative electrode lead-out sheet 32 and a positive electrode lead-out sheet 31. The negative electrode lead-out sheet 32 is connected to a plurality of negative electrode die-cut current collectors 22, and the positive electrode lead-out sheet 31 is connected to a plurality of positive electrode die-cut current collectors 2;

[0033] The negative electrode lead-out tab 32 and the positive electrode lead-out tab 31 are located on the same side.

[0034] First, a plurality of positive electrode die-cut current collectors 2 and negative electrode die-cut current collectors 22 are arranged adjacent to each other, so that the positive electrode die-cut current collectors 2 and the negative electrode die-cut current collectors 22 are arranged in a cross-zipper-like manner, that is, staggered cross-distribution; and the negative electrode lead-out sheet 32 ​​and the positive electrode lead-out sheet 31 are located on the same side;

[0035] When the solid-state laminated battery is discharged at a high rate, the electrons at the reaction interface have a shorter journey through the current collector, thereby reducing the physical impedance of the electrons passing through the battery, and improving the battery's performance indicators such as capacity, charging efficiency and cycle life.

[0036] The current collector refers to the structure or component that collects current. The battery current collector also generally includes the tabs, which are metal conductors that lead the positive and negative electrodes from the battery cell.

[0037] The function of the battery current collector is to carry the positive and negative electrode materials, and during the charge and discharge process, collect and output the current generated by the active material, or input the current to the active material. The pathway for the chemical energy and electrical energy conversion process requires good conductivity, stable chemical and electrochemical properties, high mechanical strength, and the ability to be tightly combined with the active material and not easily separated.

[0038] Taking lithium-ion batteries as an example, the current collector provides an electron channel for electrochemical reactions, accelerates the transfer of charge electrons, reduces polarization in electrochemical reactions, improves charge and discharge efficiency, and accelerates the insertion / deinsertion reaction of lithium ions.

[0039] Specifically, the spacing between adjacent positive electrode die-cut current collectors 2 and negative electrode die-cut current collectors 22 is 1-2 mm. According to the formula R=ρL / S, shortening L will effectively reduce the internal physical impedance;

[0040] It effectively reduces the distance that electrons travel through the current collector during high-rate discharge of solid-state laminated batteries and reduces the physical impedance of electrons passing through the interior.

[0041] Specifically, the total width of the positive electrode die-cut current collector 2 is the same as the total width of the negative electrode die-cut current collector 22, thereby achieving consistency in the number of electrons.

[0042] In an embodiment of the utility model, the sum of the widths of the pole pieces of the solid-state battery stack 1 is the total pole piece, and the sum of the widths of the positive electrode die-cut current collector 2 and the negative electrode die-cut current collector 22 is equivalent to 80%-90% of the total pole piece width, thereby further reducing the impedance.

[0043] In the embodiment of the utility model, the negative electrode lead-out sheet 32 ​​is fixed to the negative electrode die-cut current collector 22 by welding.

[0044] In the embodiment of the present utility model, the positive electrode lead-out piece 31 is fixedly welded to the positive electrode die-cut current collector 2.

[0045] In the embodiment of the present utility model, the positive electrode lead-out piece 31 is a current-collecting aluminum strip serving as the positive electrode tab, which reduces the R impedance, and the areas of the positive electrode die-cut current collector 2 and the negative electrode die-cut current collector 22 are symmetrical.

[0046] In the embodiment of the present utility model, the negative electrode lead-out piece 32 is a current-collecting nickel strip serving as the negative electrode tab, which reduces the R impedance, and the areas of the positive electrode die-cut current collector 2 and the negative electrode die-cut current collector 22 are symmetrical.

[0047] Specifically, the positive electrode lead-out piece 31 and the negative electrode lead-out piece 32 are arranged in a staggered manner along the height direction.

[0048] Among them Figure 1 The solid arrow is the electron channel of the positive electrode, and the hollow arrow is the electron channel of the negative electrode. Among them, the solid-state battery stack 1 can also be understood as the reaction interface.

[0049] The above are only the preferred embodiments of the present utility model, and do not limit the patent scope of the present utility model. Any equivalent structural transformation made under the inventive concept of the present utility model by using the content of the specification and drawings of the present utility model, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present utility model.

Claims

1. A zipper-type die-cut multi-electrode structure for a solid-state battery, characterized in that: include: A solid-state battery stack, the solid-state battery stack comprising a positive electrode sheet and a negative electrode sheet; A current collector, the current collector comprising a positive electrode die-cut current collector led out from the positive electrode sheet and a negative electrode die-cut current collector led out from the negative electrode sheet, the positive electrode die-cut current collector and the negative electrode die-cut current collector being arranged adjacent to each other; The positive electrode die-cut current collector and the negative electrode die-cut current collector are provided with at least two each; The lead-out structure includes a negative electrode lead-out sheet and a positive electrode lead-out sheet, wherein the negative electrode lead-out sheet is connected to a plurality of negative electrode die-cut current collectors, and the positive electrode lead-out sheet is connected to a plurality of positive electrode die-cut current collectors, The negative electrode lead-out sheet and the positive electrode lead-out sheet are located on the same side.

2. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The spacing between adjacent positive electrode die-cut current collectors and negative electrode die-cut current collectors is 1-2 mm.

3. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The total width of the positive electrode die-cut current collector is the same as the total width of the negative electrode die-cut current collector.

4. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The sum of the widths of the pole pieces of the solid-state battery stack is the total pole piece, and the sum of the widths of the positive electrode die-cut current collector and the negative electrode die-cut current collector is equivalent to 80%-90% of the total pole piece width.

5. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The negative electrode lead-out sheet and the negative electrode die-cut current collector are fixed by welding.

6. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The positive electrode lead-out sheet and the positive electrode die-cut current collector are fixed by welding.

7. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The positive electrode lead-out piece is a current collecting aluminum strip as the positive electrode tab.

8. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The negative electrode lead-out piece is a current collecting nickel strip as the negative electrode tab.

9. The zipper-type die-cut multi-electrode lug structure of a solid-state battery according to claim 1, characterized in that: The positive electrode lead-out sheet and the negative electrode lead-out sheet are staggered in height direction.

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