Coating device for battery pole piece

Abstract

The utility model discloses a coating device for a battery pole piece. The coating device comprises a coating mechanism and a supporting piece. And the coating mechanism can output slurry to the battery pole piece so as to coat the battery pole piece. The supporting piece and the coating mechanism are oppositely arranged, and the surface, facing the coating mechanism, of the supporting piece is used for supporting the battery pole piece. The supporting piece can move relative to the coating mechanism in the first direction. The surface, facing the coating mechanism, of the supporting piece is provided with a protruding part, and the protruding part extends in the first direction. According to the coating device, the depth of the thinning area can be adjusted by adjusting the height of the protruding part, and the control precision of the thinning thickness of the edge of the battery pole piece is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery equipment, in particular to a coating device for battery pole pieces. Background Art

[0002] Currently, lithium-ion battery cells generally adopt a double-ended terminal lug design (positive and negative electrodes stacked together). Within the battery cell, there is a thinned area of ​​the negative electrode corresponding to a non-thinned area of ​​the positive electrode. Because the thickness of the negative electrode sheet in the battery cell is lower than that of other areas, elemental lithium is easily precipitated on the surface of the negative electrode sheet during charging. As the number of charge and discharge cycles of the battery cell increases, the elemental lithium on the surface of the negative electrode sheet gradually accumulates, eventually piercing the separator used to separate the positive and negative electrode sheets, forming a short circuit and causing safety hazards such as combustion or even explosion of the battery cell.

[0003] Therefore, a coating pad is provided on the coating die head to coat the positive and negative electrodes. In this process, one or more thinning areas are designed on both sides and the middle area of ​​the positive and negative electrodes in the transverse direction to ensure the safety of the battery cell.

[0004] In related technologies, coating equipment primarily thins the edges of the pole pieces by reducing the output of slurry at the edges of the pole pieces. For example, this can be achieved by adjusting the structure and size of the gasket in the die, controlling coating equipment parameters, adjusting the relative position of the die and backing roller, or adjusting the slurry properties. However, this method has poor control accuracy for the thinning thickness of the pole piece edge, resulting in large fluctuations in the slurry in the thinned area of ​​the pole piece, which often results in the thickness of the thinned area not meeting the requirements. Utility Model Content

[0005] The main purpose of the utility model is to provide a coating device for battery pole pieces, aiming to solve the technical problem of poor control accuracy of the thinning thickness of the pole piece edge.

[0006] In order to achieve the above-mentioned purpose of the utility model, the utility model provides a coating device for battery pole pieces.

[0007] A coating device for a battery electrode, comprising:

[0008] a coating mechanism capable of outputting slurry to the battery electrode sheet to coat the battery electrode sheet;

[0009] A support member, wherein the support member is arranged opposite to the coating mechanism, and the surface of the support member facing the coating mechanism is used to support the battery electrode, the support member can move relative to the coating mechanism along a first direction, and the surface of the support member facing the coating mechanism is provided with a protrusion, and the protrusion is extended along the first direction.

[0010] In one embodiment, the protrusion is provided in plurality, and the plurality of protrusions are arranged at intervals along a second direction, and the second direction intersects with the first direction.

[0011] In one embodiment, the first direction is perpendicular to the second direction.

[0012] In one embodiment, the protrusion includes a protrusion body and a first inclined portion, the first inclined portion is provided on one side of the protrusion body, and the first inclined portion is provided downwardly and inclined away from the protrusion body; and / or

[0013] The protrusion further includes a second inclined portion, which is arranged opposite to the first inclined portion. The second inclined portion is arranged on the other side of the protrusion body, and the second inclined portion is arranged to be inclined downward in a direction away from the protrusion body.

[0014] In one embodiment, the first inclined portion and the second inclined portion are symmetrically arranged relative to the protruding body.

[0015] In one embodiment, the support member is a back roller, and the protrusion is arranged along the circumferential direction of the back roller; or

[0016] The supporting member is a back roller, and the protrusions are provided in plurality, and the plurality of protrusions are arranged at intervals along the axial direction of the back roller.

[0017] In one embodiment, the support member is a back plate, and the protrusion is arranged along the length direction of the back plate; or

[0018] The support member is a back plate, and the protrusions are provided in plurality, and the plurality of protrusions are arranged at intervals along the width direction of the back plate.

[0019] In one embodiment, the coating mechanism includes a first die, a second die and a gasket, the first die and the second die are arranged opposite to each other, and there is a gap between the first die and the second die, the gasket is arranged in the gap, and the gap is used for the slurry to flow to the battery electrode of the support member.

[0020] In one embodiment, the first die head is provided with a feed hole, a first groove and a second groove, the first groove is respectively connected to the second groove and the feed hole, the second groove is closer to the support member relative to the first groove, and the depth of the first groove is greater than the depth of the second groove, the slurry can pass through the feed hole, the first groove and the second groove in sequence, and flow from the second groove to the battery electrode of the support member.

[0021] In one embodiment, the gasket is provided with an escape opening, and the escape opening is communicated with the first groove and the second groove.

[0022] Beneficial effects:

[0023] The present invention relates to a coating device for battery electrodes. A coating mechanism outputs slurry to the battery electrodes to coat the battery electrodes. A support member is disposed opposite the coating mechanism, and the surface of the support member facing the coating mechanism is used to support the battery electrodes. The support member is capable of relative movement relative to the coating mechanism in a first direction. A protrusion is provided on the surface of the support member facing the coating mechanism, and the protrusion extends in the first direction. During operation, the support member moves relative to the coating mechanism, causing the battery electrodes to move relative to the coating mechanism. During the coating process of the battery electrodes by the coating mechanism, the battery electrodes located on the protrusion protrude from other locations, resulting in less slurry being applied to the battery electrodes located on the protrusion than to other locations, thereby forming a recessed portion in the battery electrodes located on the protrusion. In other words, a thinning zone is formed in the battery electrodes located on the protrusion. The thickness of the thinning zone is adapted to the height of the protrusion. Therefore, the depth of the thinning zone can be adjusted by adjusting the height of the protrusion, thereby improving the control accuracy of the thinning thickness at the edge of the battery electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a coating device for a battery electrode according to an embodiment of the present invention.

[0025] Figure 2 This is a schematic structural diagram from another angle of a coating device for a battery electrode according to an embodiment of the present invention.

[0026] Figure 3 It is a structural schematic diagram of a coating mechanism and a support member in one embodiment of the utility model.

[0027] Figure 4 It is a structural schematic diagram of the thinned area of ​​a battery electrode in one embodiment of the present utility model.

[0028] Figure 5 It is a structural schematic diagram of the first die head of an embodiment of the present utility model.

[0029] Figure 6 It is a structural schematic diagram of a gasket according to an embodiment of the present invention.

[0030] Figure 7 It is a structural schematic diagram of an embodiment of the present invention in which the supporting member is a back roller.

[0031] Figure 8 It is a structural schematic diagram of an embodiment of the present invention in which the supporting member is a back plate.

[0032] Figure 9This is a schematic diagram of coating a back plate in which the support member is an embodiment of the present invention.

[0033] in:

[0034] 100, coating mechanism; 110, first die head; 111, feed hole; 112, first groove; 113, second groove; 120, second die head; 130, gasket; 131, avoidance port;

[0035] 200, support member; 210, raised portion; 211, raised body; 212, first inclined portion; 213, second inclined portion;

[0036] 300, battery electrode; 310, thinning area.

[0037] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0038] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like, indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0040] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections, direct connections, or indirect connections through an intermediate medium; they may refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0041] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0042] like Figures 1 to 4 As shown, in some embodiments, a coating device for a battery electrode 300 includes a coating mechanism 100 and a support member 200. The coating mechanism 100 can output slurry to the battery electrode 300 to coat the battery electrode 300. The support member 200 is arranged opposite to the coating mechanism 100, and the surface of the support member 200 facing the coating mechanism 100 is used to support the battery electrode 300. The support member 200 can move relative to the coating mechanism 100 along a first direction. The surface of the support member 200 facing the coating mechanism 100 is provided with a protrusion 210, and the protrusion 210 is extended along the first direction. Specifically, the first direction is the attachment Figure 3 The first direction may be the direction in which the support member 200 moves relative to the coating mechanism 100. The first direction may be the length direction of the battery electrode 300.

[0043] During operation, the support member 200 moves relative to the coating mechanism 100, causing the battery electrode 300 to move relative to the coating mechanism 100. During the coating process of the battery electrode 300 by the coating mechanism 100, the battery electrode 300 located on the raised portion 210 protrudes from other positions, resulting in less slurry being applied to the battery electrode 300 on the raised portion 210 than on other positions, thereby forming a recessed portion in the battery electrode 300 located on the raised portion 210. That is, a thinning area 310 is formed in the battery electrode 300 located on the raised portion 210. The thickness of the thinning area 310 is adapted to the height of the raised portion 210. Therefore, the depth of the thinning area 310 can be adjusted by adjusting the height of the raised portion 210, thereby improving the control accuracy of the thinning thickness of the edge of the battery electrode 300. In addition, the shape, size, and position of the raised portion 210 can be adjusted according to different battery design requirements to obtain the desired thickness and position of the thinning area 310.

[0044] In some embodiments, the coating mechanism 100 includes a first die head 110 and a second die head 120. The first die head 110 and the second die head 120 are disposed opposite each other with a gap therebetween. The gap allows the slurry to flow to the battery electrode 300 of the support member 200. The slurry flows out of the gap and is evenly coated on the battery electrode 300 of the support member 200.

[0045] Specifically, the first die head 110 may be a lower die head, and the second die head 120 may be an upper die head. The first die head 110 and the second die head 120 are disposed opposite to each other in a vertical direction.

[0046] Specifically, the first die head 110 and the second die head 120 can be connected by a fixed structure to ensure that the relative positions are stable during the coating process. More specifically, the first die head 110 and the second die head 120 are fixed to the frame by connecting members such as bolts and nuts.

[0047] In some embodiments, the coating mechanism 100 further includes a gasket 130. The gasket 130 is disposed in the gap. The gasket 130 is capable of adjusting the gap between the first die 110 and the second die 120. That is, the thickness of the gasket 130 directly determines the size of the gap between the first die 110 and the second die 120, thereby controlling the outflow of the slurry. By selecting gaskets 130 of different thicknesses, the coating thickness can be precisely adjusted to meet the requirements of different products. For example, when a thinner coating needs to be produced, a thinner gasket 130 is selected to reduce the gap between the first die 110 and the second die 120, thereby reducing the outflow of the coating material and achieving a thinner coating thickness.

[0048] Additionally, gasket 130 acts as a seal between first die head 110 and second die head 120. Gasket 130 fits tightly between first die head 110 and second die head 120, preventing slurry from leaking from the edges of the gap. This excellent sealing performance ensures the stability and reliability of the coating process, reducing material waste and environmental pollution.

[0049] Specifically, the gasket 130 can be made of a material with elasticity and sealing properties, such as rubber, silicone, etc.

[0050] like Figure 5 As shown, in some embodiments, the first die head 110 is provided with a feed hole 111, a first groove 112, and a second groove 113. The first groove 112 is connected to the second groove 113 and the feed hole 111, respectively. The second groove 113 is closer to the support member 200 than the first groove 112, and the depth of the first groove 112 is greater than the depth of the second groove 113. The slurry can sequentially pass through the feed hole 111, the first groove 112, and the second groove 113, and flow from the second groove 113 to the battery electrode 300 of the support member 200.

[0051] It should be noted that the provision of feed hole 111, first groove 112, and second groove 113 forms an orderly slurry flow channel. First groove 112 acts as a transition and buffer. As the slurry flows from first groove 112 to second groove 113, it undergoes a process of pressure change and flow rate adjustment, allowing the slurry to flow smoothly from feed hole 111 to second groove 113. This arrangement effectively controls the flow rate and flow of the slurry, preventing turbulence or blockage when the slurry enters the die head and ensuring the stability of the coating process.

[0052] Specifically, the shapes of the first groove 112 and the second groove 113 can be rectangular grooves, arc-shaped, trapezoidal, etc.

[0053] like Figure 6 As shown, in some embodiments, the gasket 130 defines a relief opening 131 , which is in communication with the first groove 112 and the second groove 113 .

[0054] It should be noted that the avoidance opening 131 is in communication with the first groove 112 and the second groove 113, providing a continuous passage for the slurry to flow from the feed hole 111 through the first groove 112 and the second groove 113 to the battery electrode 300 on the support member 200. The avoidance opening 131 avoids obstruction of the slurry flow path by the gasket 130, ensuring that the slurry can flow smoothly in the gap, achieving coating on the battery electrode 300, thereby improving the coating quality.

[0055] Specifically, the size and shape of the avoidance opening 131 match the dimensions of the first groove 112 and the second groove 113 , so that the slurry can flow more smoothly throughout the system.

[0056] like Figure 7 As shown, in some embodiments, a plurality of protrusions 210 are provided. The plurality of protrusions 210 correspondingly form a plurality of thinned regions 310 of the battery electrode 300. The thinned regions 310 can be located on both sides or in the middle of the width direction of the battery electrode 300.

[0057] Specifically, the height of the protrusion may be 10-100 μm, and the width of the protrusion may be 5-200 mm.

[0058] Specifically, a plurality of protrusions 210 are spaced apart along the second direction, correspondingly forming a plurality of spaced thinning areas 310. The second direction is the Figure 3 The second direction intersects the first direction. More specifically, the first direction is perpendicular to the second direction.

[0059] In some embodiments, the protrusion 210 includes a protrusion body 211 and a first inclined portion 212. The first inclined portion 212 is disposed on one side of the protrusion body 211. The first inclined portion 212 is disposed downwardly and away from the protrusion body 211.

[0060] It should be noted that the first inclined portion 212 provides an inclined transition region for the thinned region 310 of the battery electrode 300. When the battery electrode 300 passes through the raised portion 210, the first inclined portion 212 can guide the electrode to gradually become thinner, avoiding a cliff-like change from normal thickness to the thinned region 310.

[0061] During the coating process, without the first inclined portion 212, the electrode sheet may suddenly become thinner at the raised body 211, leading to stress concentration and structural instability. The presence of the first inclined portion 212 allows the electrode sheet's thickness to change more gradually, reducing stress concentration during use, improving its flexibility and reliability, and extending the battery's service life.

[0062] In some embodiments, the protrusion 210 further includes a second inclined portion 213 , which is disposed opposite to the first inclined portion 212 . The second inclined portion 213 is disposed on the other side of the protrusion body 211 and is inclined downward in a direction away from the protrusion body 211 .

[0063] It should be noted that when the electrode passes through the raised body 211, the first inclined portion 212 and the second inclined portion act simultaneously, so that the transition process of the battery electrode 300 from the normal thickness to the thinned area 310 has a smooth slope in both directions, avoiding the imbalance and distortion that may be caused by unilateral inclination.

[0064] Specifically, the first inclined portion 212 and the second inclined portion 213 are symmetrically arranged relative to the raised body 211, ensuring a more uniform and stable transition of the battery electrode 300 in the thinned area 310. The symmetrical first inclined portion 212 and second inclined portion 213 make the transition of the battery electrode 300 in the thinned area 310 smoother, reducing quality issues such as electrode breakage and delamination caused by uneven thickness variations.

[0065] like Figure 7 As shown, in some embodiments, the support member 200 can be a back roller, and the protrusion 210 is arranged along the circumference of the back roller. The back roller rotates around its own rotation axis, driving the battery electrode 300 to move forward, thereby achieving continuous transmission of the battery electrode 300 in the coating device.

[0066] Specifically, a plurality of protrusions 210 are spaced apart along the axial direction of the back roller. When the back roller rotates, a specific area on the battery electrode 300 can pass through the protrusions 210, thereby forming a thinned area 310.

[0067] like Figure 8 and Figure 9 As shown, in other embodiments, the support member 200 may be a back plate. The raised portion 210 is provided along the length of the back plate. The back plate provides a stable support and a flat surface, ensuring uniform distribution of the slurry on the battery electrode 300, improving coating thickness consistency and surface flatness, and avoiding coating defects caused by electrode deformation or instability, such as uneven thickness, missing coating, and bubbles.

[0068] Specifically, the support member 200 is a back plate, and a plurality of protrusions 210 are provided. The plurality of protrusions 210 are spaced apart along the width direction of the back plate.

[0069] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A coating device for battery pole pieces, characterized in that: include: a coating mechanism capable of outputting slurry to the battery electrode sheet to coat the battery electrode sheet; A support member, wherein the support member is arranged opposite to the coating mechanism, and the surface of the support member facing the coating mechanism is used to support the battery electrode, the support member can move relative to the coating mechanism along a first direction, and the surface of the support member facing the coating mechanism is provided with a protrusion, and the protrusion is extended along the first direction.

2. The coating device according to claim 1, characterized in that The plurality of protrusions are provided, and the plurality of protrusions are spaced apart along a second direction, and the second direction intersects with the first direction.

3. The coating device according to claim 2, characterized in that The first direction is perpendicular to the second direction.

4. The coating device according to claim 1, characterized in that The protrusion includes a protrusion body and a first inclined portion, wherein the first inclined portion is provided on one side of the protrusion body and is inclined downward in a direction away from the protrusion body; and / or The protrusion further includes a second inclined portion, which is arranged opposite to the first inclined portion. The second inclined portion is arranged on the other side of the protrusion body, and the second inclined portion is arranged to be inclined downward in a direction away from the protrusion body.

5. The coating device according to claim 4, characterized in that The first inclined portion and the second inclined portion are symmetrically arranged relative to the protruding body.

6. The coating device according to claim 1, characterized in that The supporting member is a back roller, and the protrusion is arranged along the circumferential direction of the back roller; or The supporting member is a back roller, and the protrusions are provided in plurality, and the plurality of protrusions are arranged at intervals along the axial direction of the back roller.

7. The coating device according to claim 1, characterized in that The supporting member is a back plate, and the protrusion is arranged along the length direction of the back plate; or The support member is a back plate, and the protrusions are provided in plurality, and the plurality of protrusions are arranged at intervals along the width direction of the back plate.

8. The coating device according to claim 1, characterized in that The coating mechanism includes a first die head, a second die head and a gasket. The first die head and the second die head are arranged opposite to each other, and there is a gap between the first die head and the second die head. The gasket is arranged in the gap, and the gap is used for the slurry to flow to the battery electrode of the support member.

9. The coating device according to claim 8, characterized in that The first die head is provided with a feed hole, a first groove and a second groove, the first groove is respectively connected to the second groove and the feed hole, the second groove is closer to the support member relative to the first groove, and the depth of the first groove is greater than the depth of the second groove. The slurry can pass through the feed hole, the first groove and the second groove in sequence, and flow from the second groove to the battery electrode of the support member.

10. The coating device according to claim 9, characterized in that The gasket is provided with an escape opening, and the escape opening is communicated with the first groove and the second groove.

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