Reducing winding drum at winding tail end of battery cell

Abstract

The utility model relates to a variable-diameter winding drum at the winding tail end of a battery cell, which comprises a winding drum body, a through groove is formed in the winding drum body along the radial direction, a left winding bump and a right winding bump are connected in the through groove in a sliding manner, an adjusting cone is arranged between the left winding bump and the right winding bump, and the adjusting cone is connected with the left winding bump and the right winding bump in a sliding manner. The adjusting cone adjusts the left winding protruding block pole and the right winding protruding block to move left and right in the radial direction of the winding drum body through an adjusting bolt, a reset spring is connected between the left winding protruding block pole and the right winding protruding block in a hung mode, a round hole containing the adjusting cone is formed in one end of the winding drum body in the axial direction of the winding drum body, and the round hole is covered with an upper cover. According to the utility model, the pre-supporting plasticity of the winding of the battery core pole piece is realized through the variable-diameter elliptical winding drum. The problems of winding dislocation and internal shrinkage of the current pole piece can be improved, and the consistency of the wound pole piece is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium-ion batteries, and in particular to a diameter-variable winding drum for winding the end of a battery cell. Background Art

[0002] The winding drum at the end of the existing battery cell winding is a circular drum structure. Since the electrode core wound on the circular drum has no fixed force support point on the drum surface, it is easy to cause the winding core to be misaligned and shrink inward after winding.

[0003] The cell of a conventional lithium battery consists of a separator and positive and negative electrode sheets. The cells are typically wound into a cell using a winding needle, which is then used for subsequent processing. The winding needle is a core component of the winding process. Prismatic batteries manufactured using this winding process have gaps at the corners of each winding layer, preventing the inner and outer separator layers from shrinking proportionally. This can cause the inner layers of the cell to develop S-shaped shapes and wrinkles, impacting cell quality. Furthermore, prismatic batteries typically utilize a multi-tab structure. During the winding process, multiple tabs are overlapped, making their position difficult to control and affecting their alignment. To address the deformation and inner layer wrinkling issues of prismatic cells, variable tension winding is typically used. Specifically, the inner layers are wound with high tension and the outer layers with low tension. However, this method results in a lack of tension on the innermost one or two turns of the electrode sheets and separator, preventing them from shrinking and causing wrinkles in the innermost one or two turns. Furthermore, improper tension can affect the deviation correction during the winding process, or cause tab deformation. Furthermore, while some existing winding needle structures with adjustable outer circumferences can adjust the alignment of the tabs, existing adjustable outer circumference winding needles are large in size and have a relatively large minimum compatible outer circumference, making them unsuitable for some smaller battery cell models. Utility Model Content

[0004] The utility model aims to overcome the deficiencies in the prior art and provides a variable diameter winding reel for the winding end of a battery core, thereby solving the problems of winding misalignment of the core, internal shrinkage after winding, and low accuracy of lug alignment.

[0005] In order to achieve the above-mentioned purpose, the utility model is implemented through the following technical solutions: a variable diameter winding drum for the winding end of a battery cell, comprising a winding drum body, the winding drum body is provided with a through groove along its radial direction, a left winding protrusion and a right winding protrusion are slidably connected in the through groove, an adjusting cone is provided between the left winding protrusion and the right winding protrusion, the adjusting cone adjusts the left winding protrusion pole and the right winding protrusion to move left and right along the radial direction of the winding drum body through an adjusting bolt, a reset spring is hung between the left winding protrusion pole and the right winding protrusion, and one end of the winding drum body is provided with a circular hole along its axial direction for accommodating the adjusting cone, and the circular hole is covered by an upper cover.

[0006] Furthermore, the cross-section of the left-winding protrusion is rectangular, and the outer surface of the left-winding protrusion is an elliptical surface.

[0007] Furthermore, the shape of the right winding protrusion is the same as the shape of the left winding protrusion.

[0008] Furthermore, the widths of the left winding bump and the right winding bump match the width of the wound battery cell.

[0009] Furthermore, the adjusting bolt is threadedly connected to the adjusting cone, and a compression spring is provided between the adjusting bolt and the adjusting cone.

[0010] Furthermore, the adjusting bolt is screwed to the screw hole provided on the upper cover.

[0011] Beneficial Effects: Compared with the existing technology, the present invention achieves pre-stressed plasticity in the winding of the battery cell pole piece through the use of a variable diameter elliptical winding drum. This can improve the current problems of pole piece winding misalignment and internal shrinkage, and improve the consistency of the wound pole piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural diagram of the utility model;

[0013] Figure 2 It is a schematic diagram of the structure from a top view;

[0014] Figure 3 This is a working state diagram of the utility model.

[0015] In the figure: 1. Winding drum body, 2. Through slot, 3. Left winding protrusion, 3-1. Elliptical surface, 4. Right winding protrusion, 5. Adjusting cone, 6. Return spring, 7. Compression spring, 8. Round hole, 9. Upper cover, 10. Adjusting bolt. DETAILED DESCRIPTION

[0016] The following is a detailed description of the specific implementation methods provided by the present invention in conjunction with the preferred embodiments: Referring to the accompanying drawings, this embodiment provides a variable diameter winding reel for the winding end of a battery cell, comprising a winding reel body 1, the winding reel body having a through slot 2 provided along its radial direction, a left winding protrusion 3 and a right winding protrusion 4 slidably connected in the through slot, an adjustment cone 5 provided between the left and right winding protrusions, the adjustment cone adjusting the left and right winding protrusions to move radially left and right along the winding reel body via an adjustment bolt 10, a return spring 6 being mounted between the left and right winding protrusions, a circular hole 8 for accommodating the adjustment cone provided axially at one end of the winding reel body, the circular hole being covered by an upper cover 9. The upper cover is fixed by screws.

[0017] Preferably, the cross-section of the left winding protrusion is rectangular, and the outer surface of the left winding protrusion is an elliptical surface 3-1. The shape of the right winding protrusion is the same as that of the left winding protrusion.

[0018] Preferably, the widths of the left winding protrusion and the right winding protrusion match the width of the wound battery cell.

[0019] Preferably, the adjusting bolt is threadedly connected to the adjusting cone, and a compression spring 7 is provided between the adjusting bolt and the adjusting cone.

[0020] Preferably, the adjusting bolt is screwed to a screw hole provided on the upper cover.

[0021] Working process

[0022] 1. Mill a square hole along the radial direction of the circular drum to install the winding protrusion;

[0023] 2. The left winding protrusion pole and the right winding protrusion are connected in the middle by a spring;

[0024] 3. The inner side surfaces of the left winding protrusion and the right winding protrusion are inclined, and the inclined surfaces match the adjustment cone;

[0025] 4. A circular hole is made on the end face of the circular drum to install the adjusting cone, and the adjusting cone is connected to the drum end cover with bolts;

[0026] 5. When the adjustment cone is matched with the left winding protrusion pole and the right winding protrusion slope, an elliptical reel can be formed;

[0027] 6. The diameter of the elliptical reel can be adjusted by adjusting the cone.

[0028] The above-mentioned detailed description of a variable diameter winding reel for the winding end of a battery cell with reference to the embodiment is illustrative rather than restrictive, and several embodiments can be listed according to the limited scope. Therefore, changes and modifications without departing from the overall concept of the present invention should fall within the scope of protection of the present invention.

Claims

1. A variable diameter winding drum for winding the end of a battery cell, characterized by: The utility model comprises a winding drum body, wherein the winding drum body is provided with a through groove along its radial direction, a left winding protrusion and a right winding protrusion are slidably connected in the through groove, an adjusting cone is provided between the left winding protrusion and the right winding protrusion, and the adjusting cone adjusts the left winding protrusion pole and the right winding protrusion to move left and right along the radial direction of the winding drum body through an adjusting bolt, a reset spring is hung between the left winding protrusion pole and the right winding protrusion, and a circular hole for accommodating the adjusting cone is provided at one end of the winding drum body along its axial direction, and the circular hole is covered by an upper cover.

2. The variable diameter winding reel for winding the battery core according to claim 1, characterized in that: The cross section of the left winding protrusion is rectangular, and the outer surface of the left winding protrusion is an elliptical surface.

3. The variable diameter winding drum for winding the battery core according to claim 1, characterized in that: The shape of the right winding protrusion is the same as that of the left winding protrusion.

4. The variable diameter winding reel for winding the battery core according to claim 1 or 2, characterized in that: The widths of the left winding protrusion and the right winding protrusion match the width of the wound battery cell.

5. The variable diameter winding drum for winding the battery core according to claim 1, characterized in that: The adjusting bolt is threadedly connected to the adjusting cone, and a compression spring is provided between the adjusting bolt and the adjusting cone.

6. The variable diameter winding drum for winding the battery core according to claim 1 or 5, characterized in that: The adjusting bolt is screwed to the screw hole provided in the upper cover.

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