Pole piece preparation device and pole piece preparation method

Abstract

The present invention relates to a pole piece preparation device and a pole piece preparation method, the pole piece preparation device comprises: a first unwinding mechanism for unwinding and outputting a first material strip, the first material strip has a current collector and a positive electrode coating, the current collector has a plurality of coating areas arranged at intervals and a non-coating area arranged around the plurality of coating areas, and the positive electrode coating is located in the coating area; the cutting mechanism is used for cutting the second material belt, so that the insulating layer of the second material belt forms a plurality of mutually spaced first areas and continuous second areas, the first areas and the coating areas are arranged in a one-to-one correspondence manner, and the second areas and the non-coating areas are arranged in a one-to-one correspondence manner; and the compounding mechanism is used for compounding the second area of the insulating layer to the non-coating area of the first material belt and forming a positive electrode material belt with a plurality of positive electrode plate areas, and each positive electrode plate area comprises at least part of one coating area and at least part of the non-coating area surrounding the coating area.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a pole piece preparation device and a pole piece preparation method. Background Art

[0002] Solid-state batteries use solid electrolyte layers to replace the polymer separators and liquid electrolytes in existing lithium batteries. They are inherently safe and have the potential to match high-energy-density positive and negative electrode materials.

[0003] When stacking to form a solid-state battery, the solid electrolyte layer is stacked between the positive and negative electrodes. For safety and other convenience considerations, the negative electrode coating area of ​​the negative electrode sheet will be slightly larger than the positive electrode coating area of ​​the positive electrode sheet. When the stacking is completed, there is an overhead area at the edge of the stacked battery cell. When a large pressure is applied to the stacked battery cell in a direction perpendicular to the plane where the electrode sheet is located, there will be problems of uneven force and stress concentration in the overhead area, resulting in the solid-state battery being unable to meet the pressurization requirements of a larger pressure. Summary of the invention

[0004] Based on this, it is necessary to provide a pole piece preparation device and pole piece preparation method that can enable solid-state batteries to meet the pressurization requirements of higher pressures in order to address the problem that the battery architecture of traditional solid-state batteries cannot meet the pressurization requirements of higher pressures.

[0005] A pole piece preparation device, comprising:

[0006] A first unwinding mechanism is used to unwind and output a first material strip, wherein the first material strip has a current collector and a positive electrode coating, the current collector has a plurality of coating areas arranged at intervals and a non-coating area arranged around the plurality of coating areas, and the positive electrode coating is located in the coating area;

[0007] A cutting mechanism, used for cutting the second material strip so that the insulating layer of the second material strip forms a plurality of mutually spaced first regions and a continuous second region, wherein the first regions are arranged in one-to-one correspondence with the coated regions, and the second regions correspond to the non-coated regions;

[0008] A composite structure is used to composite the second area of ​​the insulating layer to the non-coated area of ​​the first material strip and form a positive electrode material strip having multiple positive electrode sheet areas, each of which includes at least a portion of the coated area and at least a portion of the non-coated area surrounded by the coated area.

[0009] In one embodiment, the pole piece preparation device comprises two cutting mechanisms, and the two cutting mechanisms are used to cut two second material strips respectively;

[0010] The composite mechanism is used to composite the second regions of the insulating layers of the two second material strips onto the front and back surfaces of the non-coated region of the first material strip, respectively, to form the positive electrode material strip.

[0011] In one embodiment, the cutting mechanism includes a back roller and a die-cutting roller, and a cutting gap is formed between the back roller and the die-cutting roller for the second material tape to pass through. The back roller is used to support the second material tape, and the die-cutting roller is used to cut the second material tape to form the first area and the second area.

[0012] In one embodiment, the composite structure includes a first hot pressing roller and a second hot pressing roller, and a hot pressing gap is formed between the first hot pressing roller and the second hot pressing roller for the first material strip and the second material strip to pass through. The first hot pressing roller and the second hot pressing roller cooperate to composite the second area with the non-coated area of ​​the first material strip.

[0013] In one embodiment, the pole piece preparation device also includes a positioning and correcting mechanism, which is located upstream of the composite mechanism and is used to correct the first material strip and / or the second material strip before the non-coated area of ​​the first material strip and the second area of ​​the insulating layer are composited.

[0014] In one of the embodiments, the pole piece preparation device further includes a second unwinding mechanism, and the second unwinding mechanism is located upstream of the cutting mechanism for unwinding and outputting the second material tape.

[0015] In one of the embodiments, the electrode sheet preparation device further includes a first winding mechanism, which is located downstream of the composite mechanism and is used to wind up the positive electrode material strip.

[0016] In one embodiment, the second material strip further includes a base film layer and a barrier layer, the insulating layer is sandwiched between the base film layer and the barrier layer, the cutting mechanism is used to cut the barrier layer and the insulating layer, and the barrier layer forms a third area and a fourth area corresponding to the first area and the second area respectively;

[0017] The electrode preparation device also includes a peeling mechanism, which is arranged between the cutting mechanism and the composite mechanism, and is used to peel off the fourth area of ​​the barrier layer. After peeling off the fourth area, the second area is separated from the base film layer when passing through the composite mechanism and is transferred to the first material tape and composited with the first material tape.

[0018] In one embodiment, the electrode preparation device further includes a waste collection mechanism, and the waste collection mechanism is disposed between the cutting mechanism and the compounding mechanism to collect the fourth region.

[0019] In one of the embodiments, the pole piece preparation device further includes a second winding mechanism, and the second winding mechanism is used to wind up the second material tape that is composited with the second region and the first material tape.

[0020] A method for preparing a pole piece, comprising the steps of:

[0021] Unwinding and outputting a first material strip, the first material strip having a current collector and a positive electrode coating, the current collector having a plurality of coating regions arranged at intervals and a non-coating region arranged around the plurality of coating regions, the positive electrode coating being located in the coating region;

[0022] Cutting the second material strip so that the insulating layer of the second material strip forms a plurality of mutually spaced first regions and a continuous second region, wherein the first regions are arranged in one-to-one correspondence with the coated regions, and the second regions correspond to the non-coated regions;

[0023] The second region of the insulating layer is compounded to the non-coated region of the first material strip to form a positive electrode material strip having multiple positive electrode sheet regions, each of which includes at least a portion of the coated region and at least a portion of the non-coated region enclosed outside the coated region.

[0024] In one embodiment, the insulating layer is an insulating adhesive layer having stickiness;

[0025] and / or

[0026] The area of ​​the second region is smaller than the area of ​​the non-coated region, so that a tab region for forming a tab is formed on the non-coated region of the positive electrode material strip.

[0027] In one embodiment, the first material strip only includes the insulating layer;

[0028] Alternatively, the first material strip further comprises a base film layer and a barrier layer, and the insulating layer is sandwiched between the base film layer and the barrier layer;

[0029] The cutting of the second material strip comprises:

[0030] Cutting the insulating layer and the barrier layer of the second material strip so that the barrier layer forms a third region and a fourth region corresponding to the first region and the second region respectively;

[0031] Before the non-coated area of ​​the first material strip and the second area of ​​the insulating layer are combined to form a positive electrode material strip, the method further includes:

[0032] peeling the fourth area off the second area;

[0033] The step of combining the non-coated area of ​​the first material strip and the second area of ​​the insulating layer to form a positive electrode material strip comprises:

[0034] After peeling off the fourth region, the second region is separated from the base film layer and transferred onto the first material tape to be combined with the first material tape to form the positive electrode material tape.

[0035] In the above-mentioned electrode sheet preparation device and electrode sheet preparation method, each positive electrode sheet area on the composite formed positive electrode material strip includes at least part of a coating area and at least part of a non-coating area surrounded by the coating area. When the positive electrode material strip is cut, each positive electrode sheet area forms a corresponding positive electrode sheet. The positive electrode coating of the positive electrode sheet formed in this way has an insulating layer on the surrounding side. Compared with the positive electrode sheet with only a positive electrode coating in the prior art, when the stack forms a solid-state battery, the insulating layer can be filled to the overhead area at the edge of the stacked battery cell. In this way, when a large pressure is applied to the stacked battery cell in a direction perpendicular to the plane where the electrode sheet is located, since at least part of the overhead area is filled with the insulating layer, the problem of uneven force and stress concentration in the overhead area is reduced, so that the solid-state battery can meet the pressurization requirements of a large pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the structure of a pole piece preparation device provided in one embodiment of the present application;

[0037] Figure 2 A composite process diagram of a positive electrode material strip formed by compositely bonding a second region of an insulating layer of a second material strip with a non-coated region of a first material strip;

[0038] Figure 3 A composite process diagram of the second region of the insulating layer of another form of the second material strip and the non-coated region of the first material strip to form a positive electrode material strip;

[0039] Figure 4 A process diagram of a second material strip in a form being cut by a cutting mechanism and a fourth region being peeled off by a peeling mechanism;

[0040] Figure 5 A schematic diagram of the structure of a positive electrode sheet;

[0041] Figure 6 A schematic diagram of the structure of a solid-state battery;

[0042] Figure 7 A flow chart of a method for preparing a pole piece provided in one embodiment of the present application.

[0043] Description of reference numerals:

[0044] 100, electrode sheet preparation device; 10, first unwinding mechanism; 20, cutting mechanism; 21, backing roller; 22, die-cutting roller; 30, compounding mechanism; 31, first hot pressing roller; 32, second hot pressing roller; 40, second unwinding mechanism; 50, waste collection mechanism; 60, first winding mechanism; 70, second winding mechanism; 200, first material strip; 201, current collector; 2011, coating area; 2012, non-coating area; 2013, pole ear area; 202, positive electrode coating; 300, second material strip; 301, base film layer; 302, insulating layer; 3021, first area; 3022, second area; 303, barrier layer; 3031, third area; 3032, fourth area; 400, positive electrode material strip; 500, positive electrode sheet; 600, negative electrode sheet; 700, solid electrolyte layer. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations 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 referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0047] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it 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 a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0050] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0051] See also Figure 1 An embodiment of the present application provides a pole piece preparation device 100, which includes a first unwinding mechanism 10, and the first unwinding mechanism 10 is used to unwind and output a first material strip 200. Figure 2 and Figure 3 The first material strip 200 has a current collector 201 and a positive electrode coating 202. The current collector 201 has a coating region 2011 and a non-coating region 2012. Specifically, there are a plurality of coating regions 2011, and the plurality of coating regions 2011 are arranged at intervals from each other, and the positive electrode coating 202 is coated on the coating regions 2011. Generally, the first material strip 200 is a material strip formed after drying and rolling processes.

[0052] The non-coated area 2012 is arranged around the plurality of coated areas 2011. Specifically, the coated area 2011 is surrounded by the non-coated area 2012, that is, each coated area 2011 is surrounded by the non-coated area 2012, and the non-coated area 2012 is in a continuous frame shape. Optionally, the current collector 201 can be made of aluminum foil, and the positive electrode coating 202 is formed on the current collector 201 by gap coating. The gap coating can leave empty foil space around the positive electrode coating 202 (active material layer), so that each coated area 2011 is surrounded by the non-coated area 2012.

[0053] Continue reading Figure 1 The electrode sheet preparation device 100 further includes a cutting mechanism 20, which is used to cut the second material strip 300. Specifically, the second material strip 300 includes an insulating layer 302, and the insulating layer 302 is made of an insulating material. When cutting the second material strip 300, the cutting mechanism 20 can cut the insulating layer 302 into a first region 3021 and a second region 3022 that can be separated from each other. Figure 4 There are multiple first regions 3021, and the multiple first regions 3021 are arranged at intervals and correspond to the coating region 2011 one by one, that is, there are as many first regions 3021 as there are coating regions 2011, and the shapes and sizes of the corresponding first regions 3021 and the coating region 2011 match. For example, when the coating region 2011 is a square region, the first region 3021 is also a square region with equal area. The second region 3022 is a continuous region that can surround the multiple first regions 3021, and the second region 3022 is arranged corresponding to the non-coating region 2012. The second region 3022 is also a frame-shaped structure, and the shapes and sizes of the second region 3022 and the non-coating region 2012 match.

[0054] In some specific implementations, please refer to Figure 2 and Figure 3 The area of ​​the second region 3022 is smaller than the area of ​​the non-coated region 2012, so that the tab region 2013 for forming the tab is formed on the non-coated region 2012 of the positive electrode strip 400 (described below) formed finally. In this way, when the positive electrode strip 400 is cut to form the positive electrode sheet 500, the corresponding tab region 2013 forms the tab of the positive electrode sheet 500.

[0055] Continue reading Figure 1The electrode sheet preparation device 100 further includes a compounding mechanism 30, which is located downstream of the first unwinding mechanism 10 and the cutting mechanism 20, and is used to compound the non-coated area 2012 of the first material strip 200 and the second area 3022 of the insulating layer 302 of the second material strip 300 to form a positive electrode material strip 400 having multiple positive electrode sheet areas. Each positive electrode sheet area includes at least a portion of a coated area 2011 and at least a portion of a non-coated area 2012 surrounding the coated area 2011. Cutting the positive electrode material strip 400 corresponding to each positive electrode sheet area can form a positive electrode sheet 500 (see Figure 5 ).

[0056] It should be noted that one coating area 2011 may correspond to one positive electrode sheet area or may correspond to multiple positive electrode sheet areas, which is not limited here.

[0057] The electrode sheet preparation device 100 provided in the present application has a first unwinding mechanism 10 that unwinds and outputs a first material strip 200, and a cutting mechanism 20 that can cut the insulating layer 302 of the second material strip 300 into a plurality of first regions 3021 and a continuous second region 3022, so that the plurality of first regions 3021 correspond to the plurality of coated regions 2011 one-to-one, and the continuous second regions 3022 correspond to the non-coated regions 2012, and a compounding mechanism 30 can compound the second regions 3022 of the insulating layer 302 with the non-coated regions 2012 of the first material strip 200 to form a positive electrode strip 400 having a plurality of positive electrode sheet regions. Since each positive electrode sheet region includes at least a portion of a coated region 2011 and at least a portion of a non-coated region 2012 surrounding the coated region 2011, when the positive electrode strip 400 is cut, each positive electrode sheet region forms a corresponding positive electrode sheet 500. The positive electrode coating 202 of the positive electrode sheet 500 thus formed has an insulating layer 302 on the periphery thereof. Compared with the positive electrode sheet 500 in the prior art that only has the positive electrode coating 202, when the sheets are stacked to form a solid-state battery, the insulating layer 302 can be filled to the overhead area at the edge of the stacked battery cell (see Figure 6 In this way, when a large pressure is applied to the laminated battery core in a direction perpendicular to the plane where the pole piece is located, since at least part of the overhead area is filled with the insulating layer 302, the problem of uneven force and stress concentration in the overhead area is reduced, so that the solid-state battery can meet the pressurization requirements of a large pressure.

[0058] In some embodiments, the positive electrode coating 202 of the positive electrode sheet 500 is surrounded by an insulating layer 302, that is, the insulating layer 302 is arranged in a ring shape outside the positive electrode coating 202. The thickness of the insulating layer 302 is equal to the thickness of the positive electrode coating 202, ensuring that when the positive electrode sheet 500 is formed, the insulating layer 302 and the surface of the positive electrode coating 202 away from the current collector 201 are flush, so as to fully contact with the solid electrolyte layer 700. In this way, the surrounding overhead layer can be filled, which is equivalent to the overhead layer no longer existing, and the problems of uneven force and stress concentration can be completely solved, so that the solid-state battery can meet the pressurization requirements of higher pressure. At the same time, such a setting can also ensure that the positive electrode coating 202 can be completely covered by the solid electrolyte layer 700 to prevent short circuits.

[0059] It is conceivable that in some other embodiments, continue to refer to Figure 5 , the insulating layer 302 may be provided only on one side or multiple sides of the positive electrode coating 202, which is not limited here. At the same time, the thickness of the insulating layer 302 may be slightly greater than or slightly less than the thickness of the positive electrode coating 202, which is not limited here.

[0060] Furthermore, the insulating layer 302 is a sticky insulating adhesive layer. Thus, when the laminated sheets form a solid-state battery, the positive electrode sheet 500 can be bonded to the solid electrolyte layer 700 through the sticky insulating layer 302, so that the positive electrode sheet 500 and the solid electrolyte layer 700 are firmly fixed, reducing the slippage of the positive electrode sheet 500 and the solid electrolyte layer 700, reducing the short circuit risk of the solid-state battery, and ensuring the safety performance of the solid-state battery.

[0061] In some embodiments, see Figure 1 The electrode sheet preparation device 100 includes two cutting mechanisms 20, and the two cutting mechanisms 20 are respectively used to cut two second material strips 300. The compounding mechanism 30 is used to compound the second regions 3022 of the insulating layers 302 of the two second material strips 300 to the front and back sides of the non-coated region 2012 of the first material strip 200, respectively, to form the positive electrode material strip 400. In this way, both sides of the first material strip 200 formed by double-sided coating can be compounded with the insulating layer 302, so that the insulating layer 302 is formed on the outer periphery of the positive electrode coating 202 on both sides of the formed positive electrode sheet 500.

[0062] It is conceivable that in other embodiments, the pole piece preparation device 100 may also include only one cutting mechanism 20, and one cutting mechanism 20 can cut a second material strip 300, or one cutting mechanism 20 can move between two workstations to meet the needs of cutting two second material strips 300.

[0063] The electrode preparation device 100 further includes a second unwinding mechanism 40, which is arranged upstream of the cutting mechanism 20 to unwind and output the second material tape 300. Optionally, when there are two cutting mechanisms 20, the number of the second unwinding mechanisms 40 is also two, and a second unwinding mechanism 40 is arranged upstream of one cutting mechanism 20, and the second material tape 300 unwinded and output by the second unwinding mechanism 40 is fed to the corresponding cutting mechanism 20 for cutting.

[0064] Further reading Figure 1 The cutting mechanism 20 includes a backing roller 21 and a die-cutting roller 22. A cutting gap is formed between the backing roller 21 and the die-cutting roller 22 for the second material strip 300 to pass through. The backing roller 21 is used to support the second material strip 300. The die-cutting roller 22 is used to cut the insulating layer 302 of the second material strip 300 to form a first area 3021 and a second area 3022. Specifically, the die-cutting roller 22 is a special roller that can cut the insulating layer 302 of the second material strip 300 into a first area 3021 and a second area 3022 of a special shape to meet the needs.

[0065] In some embodiments, see Figure 4 The second material strip 300 further includes a base film layer 301 and a barrier layer 303, and the insulating layer 302 is sandwiched between the base film layer 301 and the barrier layer 303. The base film layer 301 may be made of a polymer material such as PET, PI, or a metal material such as aluminum foil, stainless steel foil, etc. The barrier layer 303 may be made of a polymer material such as PET, and has no adhesive ability on the outside, and its function is to block the adhesive ability of the covered insulating layer 302. The cutting mechanism 20 is used to cut the second material strip 300, and the cutting depth is the sum of the thickness of the barrier layer 303 and the insulating layer 302. After being cut by the cutting mechanism 20, the barrier layer 303 forms a third region 3031 and a fourth region 3032, and the third region 3031 corresponds to the first region 3021 one by one, and the fourth region 3032 corresponds to the second region 3022. When the cutting mechanism 20 cuts the barrier layer 303 and the insulating layer 302 of the second material tape 300 , the base film layer 301 serves as a supporting and positioning layer, which facilitates the control of the tension of the second material tape 300 and can reduce the risk of tape breakage.

[0066] The electrode sheet preparation device 100 further includes a stripping mechanism (not shown in the figure), which is arranged between the cutting mechanism 20 and the compounding mechanism 30, and is used to strip the fourth region 3032 of the barrier layer 303. After the fourth region 3032 is stripped, the second region 3022 is separated from the base film layer 301 and transferred to the first material strip 200 and compounded with the first material strip 200 when passing through the compounding mechanism 30. Since the stripping mechanism tears the fourth region 3032 off the second region 3022, at this time, the second region 3022 is exposed to the outside world while the first region 3021 is still blocked by the barrier layer 303. When passing through the compounding mechanism 30, the second region 3022 exposed to the outside world is compounded with the non-coated region 2012 of the first material strip 200 to form the positive electrode material strip 400.

[0067] Further reading Figure 1 The electrode preparation device 100 further includes a waste collection mechanism 50, which is disposed between the cutting mechanism 20 and the compounding mechanism 30 to collect the peeled fourth region 3032. Specifically, the waste collection mechanism 50 is disposed in a one-to-one correspondence with the second unwinding mechanism 40, that is, each second unwinding mechanism 40 is provided with a corresponding waste collection mechanism 50.

[0068] In some other embodiments, the second material tape 300 may also omit the base film layer 301 and the barrier layer 303 and only include the insulating layer 302, which can reduce consumables and save costs. When the second material tape 300 only includes the insulating layer 302, after the cutting mechanism 20 cuts the second material tape 300, the first area 3021 and the second area 3022 can be separated, the first area 3021 is collected, and the second area 3022 is sent to the compounding mechanism 30 to be compounded with the first material tape 200.

[0069] In some embodiments, the pole piece preparation device 100 also includes a positioning and correcting mechanism (not shown in the figure), which is located upstream of the composite mechanism 30, and is used to correct the first material tape 200 and / or the second material tape 300 before the non-coated area 2012 of the first material tape 200 and the second area 3022 of the insulating layer 302 are composited, so that the non-coated area 2012 and the second area 3022 are accurately aligned to ensure the composite effect.

[0070] Continue reading Figure 1The composite mechanism 30 includes a first hot pressing roller 31 and a second hot pressing roller 32. A hot pressing gap is formed between the first hot pressing roller 31 and the second hot pressing roller 32 for the first material strip 200 and the second material strip 300 to pass through. The first hot pressing roller 31 and the second hot pressing roller 32 cooperate to make the second area 3022 composite with the non-coated area 2012 of the first material strip 200. Optionally, the material of the insulating layer 302 can be a pressure-sensitive adhesive, a heat-sensitive adhesive, or a combination of the two. When the material of the insulating layer 302 is a heat-sensitive adhesive, the material of the base film layer 301 needs to be a heat-resistant material, or a material that maintains stable mechanical properties and material properties at the corresponding hot pressing temperature.

[0071] In some embodiments, the electrode sheet preparation device 100 further includes a first winding mechanism 60 , which is used to wind up the positive electrode material strip 400 to facilitate subsequent processes, such as facilitating subsequent cutting of the positive electrode material strip 400 to form a positive electrode sheet 500 .

[0072] Furthermore, the electrode sheet preparation device 100 further includes a second winding mechanism 70 for winding the second material strip 300 after the second region 3022 is combined with the first material strip 200 for recycling. The second winding mechanism 70 is arranged in a one-to-one correspondence with the second unwinding mechanism 40 .

[0073] See also Figure 7 Another embodiment of the present application further provides a method for preparing a pole piece, comprising the steps of:

[0074] S110: unwinding and outputting a first material strip 200, the first material strip 200 having a current collector 201 and a positive electrode coating 202, the current collector 201 having a plurality of coating regions 2011 disposed at intervals and a non-coating region 2012 disposed around the plurality of coating regions 2011, and the positive electrode coating 202 being located in the coating region 2011;

[0075] S120: cutting the second material strip 300 so that the insulating layer 302 of the second material strip 300 forms a plurality of mutually spaced first regions 3021 and a continuous second region 3022, wherein the first regions 3021 are arranged in one-to-one correspondence with the coated regions 2011, and the second regions 3022 correspond to the non-coated regions 2012;

[0076] The number of first areas 3021 formed corresponds to the number of coating areas 2011, and the corresponding first areas 3021 match the shapes and sizes of the coating areas 2011. For example, when the coating area 2011 is a square area, the first area 3021 is also a square area with equal area. The second area 3022 is a continuous area that can surround multiple first areas 3021, and the second area 3022 is correspondingly arranged with the non-coating area 2012. The second area 3022 is also a frame-shaped structure, and the shapes and sizes of the second area 3022 match those of the non-coating area 2012.

[0077] S130: Compound the second region 3022 of the insulating layer 302 to the non-coated region 2012 of the first material strip 200 to form a positive electrode material strip 400 having multiple positive electrode sheet regions, each positive electrode sheet region including at least a portion of a coated region 2011 and at least a portion of a non-coated region 2012 surrounding the coated region 2011 .

[0078] Furthermore, the pole piece preparation method further comprises the steps of:

[0079] The positive electrode material strip 400 is cut corresponding to each positive electrode sheet area to form a positive electrode sheet 500 .

[0080] In some specific embodiments, the first material strip 200 is formed by single-sided coating, and the second region 3022 is compounded on the front side of the first material strip 200. In other specific embodiments, the second material strip 200 is formed by double-sided coating, and the second region 3022 is compounded on both the front and back sides of the first material strip 200, so that the insulating layer 302 is formed on the periphery of the positive electrode coating 202 on both the front and back sides of the formed positive electrode sheet 500.

[0081] The electrode sheet preparation method provided by the present application, since each positive electrode sheet area includes at least a portion of a coating area 2011 and at least a portion of a non-coating area 2012 surrounding the coating area 2011, when the positive electrode strip 400 is cut, each positive electrode sheet area corresponds to a positive electrode sheet 500, and the positive electrode coating 202 of the positive electrode sheet 500 formed in this way has an insulating layer 302 on the surrounding side. Compared with the positive electrode sheet 500 with only the positive electrode coating 202 in the prior art, when the stack forms a solid-state battery, the insulating layer 302 can be filled to the overhead area at the edge of the stack. In this way, when a large pressure is applied to the stacked battery cell in a direction perpendicular to the plane where the electrode sheet is located, since at least part of the overhead area is filled with the insulating layer 302, the problem of uneven force and stress concentration in the overhead area is reduced, so that the solid-state battery can meet the pressurization requirements of a large pressure.

[0082] Furthermore, the insulating layer 302 is a sticky insulating adhesive layer. Thus, when the laminated sheets form a solid-state battery, the positive electrode sheet 500 can be bonded to the solid electrolyte layer 700 through the sticky insulating layer 302, so that the positive electrode sheet 500 and the solid electrolyte layer 700 are firmly fixed, reducing the slippage of the positive electrode sheet 500 and the solid electrolyte layer 700, reducing the short circuit risk of the solid-state battery, and ensuring the safety performance of the solid-state battery.

[0083] In some specific embodiments, the area of ​​the second region 3022 is smaller than the area of ​​the non-coated region 2012, so that a tab region 2013 for forming a tab is formed on the non-coated region 2012 of the positive electrode strip 400 formed last. In this way, when the positive electrode strip 400 is cut to form a positive electrode sheet 500, the corresponding tab region 2013 forms the tab of the positive electrode sheet 500.

[0084] In some embodiments, the first material strip 200 only includes the insulating layer 302, which can reduce consumables and save costs. When the second material strip 300 only includes the insulating layer 302, after the second material strip 300 is cut, the first area 3021 and the second area 3022 can be separated, the first area 3021 is collected, and the second area 3022 is combined with the first material strip 200.

[0085] In some other embodiments, the second material tape 300 further includes a base film layer 301 and a barrier layer 303 , and the insulating layer 302 is sandwiched between the base film layer 301 and the barrier layer 303 .

[0086] Step S120 includes:

[0087] Cutting the insulating layer 302 and the barrier layer 303 of the second material strip 300 so that the barrier layer 303 forms a third region 3031 and a fourth region 3032 corresponding to the first region 3021 and the second region 3022 respectively;

[0088] Before step S130, the method further includes:

[0089] Peeling off the fourth region 3032 on the second region 3022;

[0090] Step S130 includes:

[0091] After peeling off the fourth region 3032 , the second region 3022 is separated from the base film layer 301 and transferred to the first material tape 200 to be combined with the first material tape 200 to form a positive electrode material tape 400 .

[0092] With the above arrangement, when the barrier layer 303 and the insulating layer 302 of the second material tape 300 are cut, the base film layer 301 serves as a supporting and positioning layer, which makes it easy to control the tension of the second material tape 300 and can reduce the risk of tape breakage.

[0093] In some embodiments, before step S130, the method further includes:

[0094] The first material strip 200 and the second material strip 300 are skewed. In this way, the first material strip 200 and / or the second material strip 300 are skewed before the non-coated area 2012 of the first material strip 200 and the second area 3022 of the insulating layer 302 are compounded, so that the non-coated area 2012 and the second area 3022 are accurately aligned to ensure the compounding effect.

[0095] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A pole piece preparation device, characterized in that: include: A first unwinding mechanism (10) is used to unwind and output a first material strip (200), wherein the first material strip (200) has a current collector (201) and a positive electrode coating (202), wherein the current collector (201) has a plurality of coating regions (2011) arranged at intervals and a non-coating region (2012) arranged around the plurality of coating regions (2011), and the positive electrode coating (202) is located in the coating region (2011); A cutting mechanism (20) for cutting the second material strip (300) so that the insulating layer (302) of the second material strip (300) forms a plurality of mutually spaced first regions (3021) and a continuous second region (3022), wherein the first regions (3021) are arranged in a one-to-one correspondence with the coated regions (2011), and the second regions (3022) correspond to the non-coated regions (2012); A composite structure (30) is used to composite the second area (3022) of the insulating layer (302) to the non-coated area (2012) of the first material strip (200) to form a positive electrode material strip (400) having multiple positive electrode sheet areas, each of which includes at least a portion of the coated area (2011) and at least a portion of the non-coated area (2012) surrounded by the coated area (2011).

2. The pole piece preparation device according to claim 1, characterized in that: The pole piece preparation device comprises two cutting mechanisms (20), and the two cutting mechanisms (20) are used to cut two second material strips (300) respectively; The composite structure (30) is used to composite the second regions (3022) of the insulating layers (302) of the two second material strips (300) to the front and back sides of the non-coated region (2012) of the first material strip (200) to form the positive electrode material strip (400).

3. The pole piece preparation device according to claim 1, characterized in that: The cutting mechanism (20) comprises a backing roller (21) and a die-cutting roller (22); a cutting gap is formed between the backing roller (21) and the die-cutting roller (22) for the second material tape (300) to pass through; the backing roller (21) is used to support the second material tape (300); and the die-cutting roller (22) is used to cut the second material tape (300) to form the first area (3021) and the second area (3022).

4. The pole piece preparation device according to claim 1, characterized in that: The composite mechanism (30) comprises a first hot pressing roller (31) and a second hot pressing roller (32); a hot pressing gap is formed between the first hot pressing roller (31) and the second hot pressing roller (32) for the first material strip (200) and the second material strip (300) to pass through; the first hot pressing roller (31) and the second hot pressing roller (32) cooperate to allow the second area (3022) to be composited with the non-coated area (2012) of the first material strip (200).

5. The pole piece preparation device according to claim 1, characterized in that: The pole piece preparation device also includes a positioning and correcting mechanism, which is located upstream of the composite mechanism (30) and is used to correct the first material strip (200) and / or the second material strip (300) before the non-coated area (2012) of the first material strip (200) and the second area (3022) of the insulating layer (302) are composited.

6. The pole piece preparation device according to claim 1, characterized in that: The pole piece preparation device further comprises a second unwinding mechanism (40), which is located upstream of the cutting mechanism (20) and is used for unwinding and outputting the second material tape (300).

7. The pole piece preparation device according to claim 1, characterized in that: The electrode sheet preparation device further comprises a first winding mechanism (60), which is located downstream of the composite mechanism (30) and is used for winding the positive electrode material strip (400).

8. The pole piece preparation device according to any one of claims 1 to 7, characterized in that: The second material strip (300) further comprises a base film layer (301) and a barrier layer (303); the insulating layer (302) is sandwiched between the base film layer (301) and the barrier layer (303); the cutting mechanism (20) is used to cut the barrier layer (303) and the insulating layer (302); the barrier layer (303) forms a third region (3031) and a fourth region (3032) corresponding to the first region (3021) and the second region (3022), respectively; The electrode preparation device also includes a peeling mechanism, which is arranged between the cutting mechanism (20) and the composite mechanism (30) and is used to peel off the fourth area (3032) of the barrier layer (303). After peeling off the fourth area (3032), the second area (3022) is separated from the base film layer (301) when passing through the composite mechanism (30) and is transferred to the first material tape (200) to be composited with the first material tape (200).

9. The pole piece preparation device according to claim 8, characterized in that: The pole piece preparation device further comprises a waste collection mechanism (50), wherein the waste collection mechanism (50) is arranged between the cutting mechanism (20) and the compounding mechanism (30) and is used for collecting the fourth region (3032).

10. The pole piece preparation device according to claim 8, characterized in that: The pole piece preparation device further comprises a second winding mechanism (70), wherein the second winding mechanism (70) is used to wind up the second material strip (300) formed by combining the second region (3022) with the first material strip (200).

11. A method for preparing a pole piece, characterized in that: Includes steps: Unwinding and outputting a first material strip (200), the first material strip (200) having a current collector (201) and a positive electrode coating (202), the current collector (201) having a plurality of coating regions (2011) arranged at intervals and a non-coating region (2012) arranged around the plurality of coating regions (2011), the positive electrode coating (202) being located in the coating region (2011); Cutting the second material strip (300) so that the insulating layer (302) of the second material strip (300) forms a plurality of mutually spaced first regions (3021) and a continuous second region (3022), wherein the first regions (3021) are arranged in one-to-one correspondence with the coated regions (2011), and the second regions (3022) correspond to the non-coated regions (2012); The second region (3022) of the insulating layer (302) is compounded to the non-coated region (2012) of the first material strip (200) to form a positive electrode material strip (400) having a plurality of positive electrode sheet regions, each of the positive electrode sheet regions including at least a portion of the coated region (2011) and at least a portion of the non-coated region (2012) enclosed outside the coated region (2011).

12. The method for preparing a pole piece according to claim 11, characterized in that: The insulating layer (302) is a sticky insulating adhesive layer; and / or The area of ​​the second region (3022) is smaller than the area of ​​the non-coated region (2012), so that a pole lug region (2013) for forming a pole lug is formed on the non-coated region (2012) of the positive electrode material strip (400).

13. The method for preparing a pole piece according to claim 11, characterized in that: The first material strip (200) only includes the insulating layer (302); Alternatively, the first material strip (200) further comprises a base film layer (301) and a barrier layer (303), and the insulating layer (302) is sandwiched between the base film layer (301) and the barrier layer (303); The cutting of the second material strip (300) comprises: Cutting the insulating layer (302) and the barrier layer (303) of the second material strip (300) so that the barrier layer (303) forms a third region (3031) and a fourth region (3032) corresponding to the first region (3021) and the second region (3022), respectively; Before the non-coated area (2012) of the first material strip (200) and the second area (3022) of the insulating layer (302) are combined to form the positive electrode material strip (400), the method further includes: peeling off the fourth region (3032) on the second region (3022); The step of compounding the non-coated region (2012) of the first material strip (200) and the second region (3022) of the insulating layer (302) to form a positive electrode material strip (400) comprises: After peeling off the fourth region (3032), the second region (3022) is separated from the base film layer (301) and transferred onto the first material tape (200) to be combined with the first material tape (200) to form the positive electrode material tape (400).

Images