Method for manufacturing battery electrode plates, battery electrode plates, and battery
By dividing the current collector into regions with varying coating layer densities to form guide channels, the electrolyte penetration and distribution issues in power battery electrode plates are resolved, improving energy density and charging performance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- HUIZHOU EVE POWER CO LTD
- Filing Date
- 2023-09-20
- Publication Date
- 2026-04-14
AI Technical Summary
Existing power battery electrode plates face challenges with electrolyte penetration and distribution due to their thickness, leading to slow transfer speeds and non-uniform distribution, which limits rapid charging performance and service life.
The electrode plates are manufactured with a current collector divided into regions, forming coating layers with varying surface densities, creating guide channels for electrolyte circulation, ensuring easy penetration and distribution.
This method enhances electrolyte transfer, resulting in higher energy density, faster charging, and extended battery life by facilitating uniform electrolyte distribution and accommodating electrode expansion.
Smart Images
Figure 2026511684000001_ABST
Abstract
Description
Technical Field
[0001] This application claims the priority of Chinese patent applications with application numbers 202310620463.7 and 202321344604.9, filed with the Chinese Patent Office on May 30, 2023, and all the contents of the above applications are incorporated herein by reference.
[0002] This application relates to the technical field of power batteries, for example, a method for manufacturing a battery electrode plate, a battery electrode plate, and a battery.
Background Art
[0003] High energy density, ultra-rapid charging, and long life are the main development directions of power batteries. In related technologies, the electrode plate of a power battery improves the energy density of the power battery by increasing the thickness to improve the filling amount of the active material. However, it is difficult for the electrolyte to penetrate into the thick electrode, which affects the transfer speed of the electrolyte. On the other hand, during the use process of the power battery, the thick electrode plate is more likely to expand, and after being pressed, the electrolyte in the electrode plate is more likely to be extruded, resulting in non-uniform distribution of the electrolyte, and limiting the rapid charging performance and service life of the power battery.
Summary of the Invention
Problems to be Solved by the Invention
[0004] In this application, a guide flow path for circulating the electrolyte on the current collector during the coating process is ensured, the manufacturing method is simple and easy to perform, the electrolyte is difficult to penetrate in the battery cell, the transfer speed is slow, and the problem of non-uniform distribution of the electrolyte due to the expansion of the electrode plate during the use process of the battery cell is solved, realizing the high energy density of the battery, and at the same time, a manufacturing method of a battery electrode plate, a battery electrode plate, and a battery that can achieve rapid charging performance and service life are provided.
Means for Solving the Problems
[0005] As a first aspect, in this application, dividing one side surface of the current collector into a first region and a second region, The coating machine is controlled to coat the first region and the second region, forming a first coating layer in the first region and a second coating layer in the second region, wherein the surface density of the first coating layer is greater than that of the second coating layer, the first and second coating layers form a coating layer, and the second coating layer forms a guide channel on the coating layer. The guide channel is provided along at least one of the first, second, and third directions, wherein the second direction is provided at an angle to the first direction, and the first direction is perpendicular to the third direction. When multiple guide channels are provided, at least some of the guide channels are arranged at intervals and at least one of the arrangements where they intersect, and the guide channels are located at an intermediate position on one side of the current collector, or at least one end of the guide channels extends to the edge of one side of the current collector. This invention provides a method for manufacturing battery electrode plates.
[0006] In one embodiment, After controlling the coating machine to coat the first region and the second region, The thickness of the second coating layer is to be less than or equal to the thickness of the first coating layer, The consolidation density of the second coating layer is to be less than or equal to the consolidation density of the first coating layer, The thickness of the second coating layer is to be less than or equal to the thickness of the first coating layer, and the consolidation density of the second coating layer is to be less than or equal to the consolidation density of the first coating layer. To achieve one of the following: The method further includes compacting the first coating layer and the second coating layer.
[0007] In one embodiment, The other side of the current collector is divided into a third region and a fourth region, The coating machine is controlled to coat the third and fourth regions, forming a third coating layer in the third region and a fourth coating layer in the fourth region, wherein the surface density of the third coating layer is greater than that of the fourth coating layer. It also includes.
[0008] In the second aspect, in this application, A battery electrode plate, manufactured by employing the above-described method for manufacturing a battery electrode plate, comprising: a current collector having a first region and a second region on one side surface; a first coating layer provided in the first region; and a second coating layer provided in the second region, wherein the first and second coating layers form a coating layer provided on one side surface of the current collector, the surface density of the first coating layer is greater than that of the second coating layer, and the second coating layer forms a guide channel on the coating layer. We provide battery plates.
[0009] In one embodiment, a uniform coating layer is provided on the other side surface of the current collector, or the other side surface of the current collector is divided into a third region where a third coating layer is provided and a fourth region where a fourth coating layer is provided, wherein the surface density of the third coating layer is greater than that of the fourth coating layer.
[0010] In one embodiment, the surface density of the third coating layer is 0.6 to 1.4 times that of the first coating layer.
[0011] In one embodiment, the second coating layer and the fourth coating layer overlap at least partially along a direction perpendicular to the current collector.
[0012] In one embodiment, when a uniform coating layer is provided on the other side surface of the current collector, the range of the ratio of the projected area of the second coating layer on the current collector to the total surface area of the current collector is 0.0001 to 0.5, or when a third coating layer and a fourth coating layer are provided on the other side surface of the current collector, the range of the ratio of the sum of the projected areas of the second coating layer and the fourth coating layer on the current collector to the total surface area of the current collector is 0.0001 to 0.5.
[0013] In one embodiment, the third and fourth coating layers are provided on the other side surface of the current collector, and the coating layers formed by the first and second coating layers and the coating layers formed by the third and fourth coating layers are provided symmetrically or asymmetrically on both sides of the current collector.
[0014] In one embodiment, on one side of the current collector, one or more layers of coatings formed by the first coating and the second coating are provided along the thickness direction.
[0015] In one embodiment, the first coating and the second coating are such that the thickness of the second coating is less than or equal to the thickness of the first coating, the consolidation density of the second coating is less than or equal to the consolidation density of the first coating, the thickness of the second coating is less than or equal to the thickness of the first coating and the consolidation density of the second coating is less than or equal to the consolidation density of the first coating, and are configured in any of the above manners.
[0016] In one embodiment, the areal density S1 of the first coating ≤ 600 g / m 2 , the thickness H1 of the first coating ≤ 500 μm, the consolidation density P1 of the first coating ≤ 4.2 g / cc, the areal density S2 of the second coating ≤ 400 g / m 2 , the thickness H2 of the second coating ≤ 300 μm, the consolidation density P2 of the second coating ≤ 4.0 g / cc, or the areal density S2 of the second coating ≤ 400 g / m 2 , the thickness H2 of the second coating ≤ 500 μm, the consolidation density P2 of the second coating ≤ 2.0 g / cc.
[0017] In one embodiment, the thickness of the first coating is greater than the thickness of the second coating, and the value range of the ratio of the thickness of the second coating to the thickness of the first coating is greater than zero and less than 0.995.
[0018] In one embodiment, the thickness of the first coating is greater than the thickness of the second coating, and between the first coating and the second coating, there is a Guide channel formed with a cross-sectional shape that is arcuate or rectangular or trapezoid-like.
[0019] In one embodiment, the value range of the ratio of the areal density of the second coating to the areal density of the first coating is greater than zero and less than 0.99.
[0020] In one embodiment, one or more guide channels are provided in the coating layer.
[0021] In one embodiment, a plurality of guide channels are provided in the coating layer, and at least some of the guide channels are provided at intervals or at least some of the guide channels are provided to intersect.
[0022] In one embodiment, one second coating layer is provided on one side surface of the current collector, and the second region is located at an intermediate position of the current collector, or at least one end of the second region extends to the edge of the current collector.
[0023] In one embodiment, a plurality of second coating layers are provided at intervals on one side surface of the current collector, and each second coating layer is provided in one second region. The plurality of second regions are such that the plurality of second regions are located at an intermediate position of the current collector, at least one end of at least one second region extends to the edge of the current collector, at least one end of at least one second region extends to the edge of the current collector and the remaining second regions are located at an intermediate position of the current collector, and are configured in any of the above manners.
[0024] In one embodiment, when the battery electrode plate is configured as the positive electrode plate of the battery cell, the materials of the first coating layer and the second coating layer are a ternary positive electrode material , a lithium iron phosphate positive electrode material and a sodium ion positive electrode material and are at least one of them. When the battery electrode plate is configured as the negative electrode plate of the battery cell, the materials of the first coating layer and the second coating layer are at least one of artificial graphite, natural graphite, hard carbon, soft carbon, silicon and metal materials capable of forming an alloy with lithium and sodium.
[0025] In one embodiment, the first coating layer and the second coating layer are coated on the surface of the current collector, or The battery electrode plate further comprises at least one intermediate coating layer provided on the surface of the current collector, the first coating layer and the second coating layer being coated on the surface of the intermediate coating layer away from the current collector.
[0026] In a third aspect, the present invention provides a battery comprising a positive electrode plate, a negative electrode plate, and a separator provided between the positive electrode plate and the negative electrode plate, wherein at least one of the positive electrode plate and the negative electrode plate is the battery electrode plate described above.
[0027] In one embodiment, when the positive electrode plate is the battery electrode plate, the range of the ratio of the surface density of the second coating layer to the surface density of the first coating layer is greater than zero and less than 0.99, or When the negative electrode plate is the battery electrode plate, the range of the ratio of the surface density of the second coating layer to the surface density of the first coating layer is greater than 0.8 and less than 0.99, or When both the positive electrode plate and the negative electrode plate are battery electrodes, and the positive electrode plate and the negative electrode plate located on opposite sides of the same separator do not overlap in a direction perpendicular to the separator, the range of the ratio of the surface density of the second coating layer of the positive electrode plate to the surface density of the first coating layer is greater than zero and less than 0.99, and the range of the ratio of the surface density of the second coating layer of the negative electrode plate to the surface density of the first coating layer is greater than 0.8 and less than 0.99, or When both the positive electrode plate and the negative electrode plate are battery electrode plates, and the positive electrode plate and the negative electrode plate located on opposite sides of the same separator overlap in a direction perpendicular to the separator, the following conditions hold: 40%min{area of the second region of the positive electrode plate, area of the second region of the negative electrode plate} ≤ overlapping area ≤ max{area of the second region of the positive electrode plate, area of the second region of the negative electrode plate}, and the range of the ratio of the surface density of the second coating layer of the positive electrode plate to the surface density of the first coating layer is greater than 0.01 and less than 0.99, and the range of the ratio of the surface density of the second coating layer of the negative electrode plate to the surface density of the first coating layer is greater than 0.4 and less than 0.99. [Effects of the Invention]
[0028] The beneficial effects of this application are as follows:
[0029] In the battery electrode plate manufacturing method, battery electrode plate, and battery according to the present invention, the battery electrode plate manufactured by the battery electrode plate manufacturing method has a first coating layer and a second coating layer formed on one side surface of the current collector, and the surface density of the first coating layer is greater than the surface density of the second coating layer, which is a guide channel. By taking the above steps, a guide channel for circulating the electrolyte during the coating process on the current collector can be secured, and the manufacturing method is simple and easy to carry out, as it only requires changing the surface density of the coating layers in different regions.
[0030] By forming guide channels in the coating layer, the flow of the electrolyte within the guide channels becomes easier, resulting in higher energy density, faster charging performance, and longer service life of the battery, while also solving the problem of difficulty in electrolyte penetration.
[0031] When multiple guide channels are provided, the guide channels are ,collectionThe guide channel is located at an intermediate position on the side of the current collector, or at least one end of the guide channel extends to the edge of the side of the current collector. Exemplary examples include the guide channel being located at an intermediate position, one end of the guide channel extending to the edge, and both ends of the guide channel extending to the edge. The guide channel is linear, curved, or closed, and the shapes of each guide channel may be all the same, partially the same, or both different, and the shape may be one of the above shapes. The battery plates are connected to the battery cell along a first direction, and guide channels are provided along a first direction and / or a second direction and / or a third direction, wherein the second direction is provided at an angle to the first direction, the first direction is perpendicular to the third direction, and at least some of the guide channels are spaced apart, and / or at least some of the guide channels are intersecting, and exemplary cases include cases where all of the guide channels are intersecting, cases where all of the guide channels are spaced apart, and cases where some of the guide channels are intersecting and some of the other guide channels are spaced apart. Combining the above cases results in various combinations, and the more guide channels there are and the more dispersed the structure, the more advantageous the transfer of the electrolyte becomes, improving the rapid charging cycle performance of the battery cell. [Brief explanation of the drawing]
[0032] [Figure 1] This is a schematic diagram of the first battery electrode plate according to an embodiment of the present application. [Figure 2] This is a side view of the second battery electrode plate according to an embodiment of the present application. [Figure 3] This is a top view of the third battery electrode plate according to an embodiment of the present application. [Figure 4] This is a top view of the fourth battery electrode plate according to an embodiment of the present application. [Figure 5] This is a top view of the fifth battery electrode plate according to an embodiment of the present application. [Figure 6] This is a top view of the sixth battery electrode plate according to an embodiment of the present application. [Figure 7] This is a top view of the seventh battery electrode plate according to an embodiment of the present application. [Figure 8] This is a top view of the eighth battery electrode plate according to an embodiment of the present application. [Figure 9] This is a top view of the ninth battery electrode plate according to an embodiment of the present application. [Figure 10] This is a top view of the tenth battery electrode plate according to an embodiment of the present application. [Figure 11] This is a flowchart of the method for manufacturing a battery electrode plate according to an embodiment of the present invention. [Figure 12] This is a schematic diagram of a stacked battery cell according to an embodiment of the present invention, in which a battery electrode plate is used only for the positive electrode. [Figure 13] This is a schematic diagram of a stacked battery cell according to an embodiment of the present invention, in which battery plates are used for both the positive and negative electrodes. [Explanation of symbols]
[0033] In the figure: 1... Current collector, 2... 1st coating layer, 3... 2nd coating layer, 4... 3rd coating layer, 5... 4th coating layer, 6... Guide channel 100... Positive plate, 200... Negative plate, 300... Separator. [Modes for carrying out the invention]
[0034] In this description, unless otherwise explicitly defined and limited, the terms “connected,” “connected,” and “fixed” should be understood in a broad sense, and may include, for example, fixed connections, removable connections, or integral connections, mechanical connections or electrical connections, direct connections or indirect connections via an intermediate medium, or internal communication between two elements or an interaction relationship between two elements. A person skilled in the art will be able to understand the specific meaning of these terms in this application depending on the specific circumstances.
[0035] In this application, unless otherwise clearly defined and limited separately, for the first feature to be "above" or "below" the second feature may include that the first feature and the second feature are in direct contact, or may include that the first feature and the second feature are not in direct contact and are in contact through another feature therebetween. Further, for the first feature to be "above", "upper" and "upper surface" of the second feature includes that the first feature is directly above and obliquely above the second feature, or simply represents that the horizontal height of the first feature is higher than that of the second feature. For the first feature to be "below", "lower" and "lower surface" of the second feature includes that the first feature is directly below and obliquely below the second feature, or simply represents that the horizontal height of the first feature is lower than that of the second feature.
[0036] In this embodiment, a battery is provided. As shown in FIGS. 12 and 13, the battery includes a positive electrode plate 100, a negative electrode plate 200, and a separator 300 provided between the positive electrode plate 100 and the negative electrode plate 200. Among them, the positive electrode plate 100, the negative electrode plate 200, and the separator 300 may be a laminated battery cell or a wound battery cell so as to form a battery. The battery may be various types of batteries such as a pouch battery, a prismatic battery, or a cylindrical battery. In this embodiment, a battery electrode plate is further provided, and the positive electrode plate 100 and / or the negative electrode plate 200 employs the battery electrode plate of this embodiment.
[0037] As shown in FIG. 1, the battery electrode plate includes a current collector 1 and coatings provided on both sides of the current collector 1, and a guide flow path is provided in at least one of the coatings.
[0038] In one case, when a guide flow path is provided in the coating on the first side of the current collector 1 and a uniform coating is provided on the second side, the coating on the first side includes a first coating 2 and a second coating 3. The first coating 2 and the second coating 3 are provided in two regions (a first region and a second region) on one side surface of the current collector 1 respectively. The areal density of the first coating 2 is S1, and the areal density of the second coating 3 is S2, where S2 < S1. By reducing the areal density of the local coating on the coating, that is, the second coating 3, a guide flow path is formed, and the electrolyte flows more easily on the second coating 3 with a low areal density. That is, the second coating 3 forms a guide flow path on the coating.
[0039] In the second case, when a uniform coating layer is provided on the first side of the current collector 1 and guide channels are provided in the coating layer on the second side, the other side of the current collector 1 is divided into a third region and a fourth region, and the coating layer on the second side includes a third coating layer 4 and a fourth coating layer 5, with the third region having the third coating layer 4 and the fourth region having the fourth coating layer 5, the surface density of the third coating layer 4 being greater than the surface density of the fourth coating layer 5, and the electrolyte flows more easily over the low surface density fourth coating layer 5, that is, the fourth coating layer 5 forms guide channels on the coating layer.
[0040] In the third case, guide channels are provided in both of the coating layers on either side of the current collector 1.
[0041] Preferably, the surface density of the third coating layer 4 is 0.6 to 1.4 times that of the first coating layer 2, in order to avoid a large difference in the amount of active material used in the coating layers on both sides of the current collector 1 that would affect the operation of the battery cell.
[0042] The coating layer may be applied directly to the surface of the current collector 1, or an intermediate coating layer may be provided between the coating layer and the surface of the current collector 1. For example, both the first coating layer 2 and the second coating layer 3 may be applied to the surface of the same intermediate coating layer.
[0043] The electrolyte can flow through the guide channel, solving the problem of active material expansion affecting electrolyte penetration and retention capacity during battery cell use. A coating layer is provided on the side of the current collector 1, ensuring the amount of active material filled, achieving high energy density in the battery, while also improving rapid charging performance and service life.
[0044] Preferably, the range of the ratio value between the surface density of the second coating layer 3 and the surface density of the first coating layer 2 is greater than zero and less than 0.99. Alternatively, the range of the ratio value between the surface density of the second coating layer 3 and the surface density of the first coating layer 2 is greater than 0.1 and less than 0.9, for example, the surface density ratio values are 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, and 0.8. A larger surface density ratio value results in a smaller space for the formed guide channel, which is unfavorable for electrolyte transfer, while a smaller ratio value means less active material on the electrode plate, which affects the capacity of the battery cell.
[0045] In one embodiment, the thickness of the first coating layer 2 is H1, and the thickness of the second coating layer 3 is H2, where H2 ≤ H1, meaning that the second coating layer 3 is relatively thinner on the coating layer, i.e., concave. groove By forming this, a recess occurs within the battery cell. in the groove This ensures that the electrolyte can be quickly transferred and stored. In other words , guide channel Functions as 6 Preferably, the thickness of the first coating layer 2 is greater than the thickness of the second coating layer 3, and the range of the ratio value between the thickness of the second coating layer 3 and the thickness of the first coating layer 2 is greater than zero and less than 0.995. Alternatively, the range of the ratio value between the thickness of the second coating layer 3 and the thickness of the first coating layer 2 is greater than 0.2 and less than 0.9. For example, the values of the thickness ratio are 0.3, 0.4, 0.5, 0.6, 0.7, and 0.8. A larger value of the thickness ratio results in a smaller space in the guide channel, which is unfavorable for electrolyte transfer and does not clearly improve the rapid charging and cycling of the battery cell. On the other hand, a smaller value of the ratio means that there is less active material on the electrode plate, which affects the capacity of the battery cell. Preferably, the thickness of the first coating layer 2 is greater than the thickness of the second coating layer 3, and the cross-sectional shape between the first coating layer 2 and the second coating layer 3 is arc-shaped, rectangular, or trapezoidal. Guide channel 6 is formed.
[0046] In another embodiment, the consolidation density of the first coating layer 2 is P1, and the consolidation density of the second coating layer 3 is P2, where P2 ≤ P1. The difference in consolidation densities between the first and second coating layers 2 and 3 results in more voids in the low-consolidation areas of the second coating layer 3, facilitating electrolyte transfer and thus forming guide channels. The thicknesses of the first and second coating layers 2 and 3 may be the same or different, and are not limited here. Different consolidations can be achieved by cold pressing to make the first and second coating layers 2 and 3 the same thickness and adjusting the surface density. A larger difference between P2 and P1 indicates a higher void ratio within the coating layers in the guide channels, which is advantageous for electrolyte transfer and effectively improves the rapid charging cycle performance of the battery cell.
[0047] The guide channel may exist only in the coating layer on one side of the current collector 1, or it may exist simultaneously in the coating layers on both sides. The total projected area of the guide channel on the current collector 1 is A2, and the total surface area of the current collector 1 is A, where the range of A2 / A is 0.0001 to 0.5. Preferably, for example, 0.0001, 0.0005, 0.001, 0.005, 0.01, 0.05, 0.1 and 0.5, etc. For example, if a uniform coating layer is provided on one side of the current collector 1, the projected area of the second coating layer 3 on the current collector 1 is A2. Preferably, the range of A2 / A is 0.001 to 0.3. When guide channels are provided on both sides of the current collector 1, the sum of the projections of the second coating layer 3 and the fourth coating layer 5 on the current collector 1 is A2. Preferably, the range of A2 / A is 0.01 to 0.1. This avoids the guide channel occupying too large an area, which would affect the amount of active material packed, and also avoids the occupying too small an area, which would prevent it from effectively transferring the electrolyte, thus affecting the improvement in the rapid charging and cycling performance of the battery cell. 。
[0048] As shown in Figure 2, guide channels are provided in both coating layers on both sides of the current collector 1, and the coating layers on both sides are provided symmetrically / asymmetrically on both sides of the current collector 1. For example, the first coating layer 2 and the second coating layer 3 are provided on one side of the current collector 1, and the third coating layer 4 and the fourth coating layer 5 are provided on the other side of the current collector 1, and the coating layer formed by the first coating layer 2 and the second coating layer 3 and the coating layer formed by the third coating layer 4 and the fourth coating layer 5 are provided symmetrically / asymmetrically on both sides of the current collector 1. The guide channels on both sides of the current collector 1 may be in the same vertical direction of the current collector 1, or they may be in different vertical directions, i.e., offset vertically. That is, the shape, size, position, distribution, and number of guide channels in the coating layers on both sides of the current collector 1 may be the same or different. The structure of the guide channels on both sides can increase the uniformity of the distribution of guide channels in the battery cell, provide more transfer channels to the electrolyte, and improve the effect on the rapid charging cycle of the battery cell. However, designing too many guide channels on both sides leads to increased difficulty in manufacturing and a decrease in the amount of active material to be filled, affecting the capacity. Preferably, the second coating layer 3 and the fourth coating layer 5 overlap at least partially along a direction perpendicular to the current collector 1.
[0049] The number of guide channels on the coating layer is not limited; that is, the number of guide channels on both sides of the current collector 1 is not limited, and as shown in Figure 2, one guide channel is provided on each side of the coating layer on both sides of the current collector 1. The number and arrangement of guide channels on one side of the current collector 1 are described exemplarily. In one embodiment, as shown in Figure 1, one guide channel is provided in the coating layer. In another embodiment, as shown in Figures 3 to 10, multiple guide channels are provided in the coating layer. As shown in Figure 3, two guide channels are provided in the coating layer. In other embodiments, three, four, or five or more guide channels may be provided. The more numerous and the more dispersed the structure of the guide channels, the more advantageous it is for electrolyte transfer and the faster charging cycle performance of the battery cell is improved. However, an excessive number of guide channels increases the difficulty of processing the electrode plate while reducing the capacity of the battery cell.
[0050] The position of the guide channels on the coating layer is not limited. In one embodiment, as shown in Figures 1 to 5 and Figure 7, the guide channels extend to the edge of the coating layer, but they may extend to one edge of the coating layer as shown in Figure 7, or to two edges of the coating layer as shown in Figure 3. In one embodiment, as shown in Figure 6, the guide channels are located in the middle of the coating layer. When multiple guide channels are provided, one end of one of the guide channels may extend to the edge of the coating layer, and both ends of each of the other guide channels may extend to the edge of the coating layer, or neither end of each guide channel may extend to the edge of the coating layer, meaning that all guide channels are located in the middle of the coating layer. In other words, multiple guide channels located in the same coating layer may have any combination of the above situations in which the position of each guide channel is located, and this is not limited here.
[0051] The second region where the second coating layer 3 is located is rectangular, and accordingly, the projection of the guide channel onto the current collector 1 is rectangular. The length of the first region where the first coating layer 2 is located is less than or equal to the length of the second region, and the width of the first region is less than or equal to the width of the second region.
[0052] The shape of the guide channel in the coating layer is not limited. As shown in Figures 1 to 3, the guide channel is provided along a first direction, the battery electrode plate is connected to the battery cell along the first direction, that is, both directions are the same, and the guide channel is provided in a straight line. As shown in Figure 4, the guide channel is provided along a second direction, the battery electrode plate is connected to the battery cell along the first direction, the second direction is provided at an angle with the first direction, and if the angle is acute, that is, the guide channel is provided at an incline. As shown in Figure 5, the guide channel is provided along a third direction, the battery electrode plate is connected to the battery cell along the first direction, and the first direction is perpendicular to the third direction. The guide channel may also be curved or closed.
[0053] In one embodiment, as shown in Figures 3 to 10, the coating layer is provided with a plurality of guide channels, as shown in Figures 3 to 8, at least some of the guide channels are spaced apart, as shown in Figures 9 and 10, at least some of the guide channels are intersecting, as shown in Figure 9, all of the guide channels are in communication, or as shown in Figure 1, some of the guide channels are in communication.
[0054] In one embodiment, multiple guide channels are provided along a first direction, and the multiple guide channels are distributed at equal intervals or unevenly. In another embodiment, multiple guide channels are provided along a second direction, and the multiple guide channels are distributed at equal intervals or unevenly. In yet another embodiment, multiple guide channels are provided along a third direction, and the multiple guide channels are distributed at equal intervals or unevenly. The above three embodiments may be combined arbitrarily, for example, one guide channel along the third direction and two guide channels along the first direction, with the three guide channels intersecting each other; or three guide channels along the third direction and two guide channels along the first direction; or one guide channel along the third direction and three guide channels along the second direction; or two guide channels along the third direction and three guide channels along the second direction; and are not limited to these. All of the above guide channels extend to the edge of the coating layer, or some of the guide channels extend to the edge of the coating layer. The guide channels provided along the two directions described above either completely intersect or partially intersect.
[0055] The width and length of the guide channel are not limited.
[0056] One or more coating layers are provided on one side of the current collector 1 along the thickness direction, and can be selected according to the needs. For example, one side of the current collector 1 is provided with one or more coating layers formed by a first coating layer 2 and a second coating layer 3 along the thickness direction. The other side of the current collector 1 is provided with one or more coating layers formed by a third coating layer 4 and a fourth coating layer 5 along the thickness direction.
[0057] When the above-mentioned battery electrode plate is used for the positive electrode plate 100, the coating layer is one of the ternary positive electrode layer, the lithium iron positive electrode layer, and the sodium ion positive electrode layer. When the above-mentioned battery electrode plate is used for the negative electrode plate 200, the coating layer is one of the artificial graphite layer, the natural graphite layer, the hard carbon layer, the soft carbon layer, the silicon layer, and the metallic material layer capable of forming an alloy with lithium sodium.
[0058] In the first embodiment, when only the positive electrode plate 100 is a battery electrode plate, the range of the ratio of the surface density of the second coating layer 3 to the surface density of the first coating layer 2 is greater than zero and less than 0.99.
[0059] In the second embodiment, when only the negative electrode plate 200 is a battery electrode plate, the range of the ratio of the surface density of the second coating layer 3 to the surface density of the first coating layer 2 is greater than 0.8 and less than 0.99.
[0060] In the third embodiment, both the positive electrode plate 100 and the negative electrode plate 200 are battery electrodes, and when the positive electrode plate 100 and the negative electrode plate 200, located on opposite sides of the same separator 300, do not overlap in a direction perpendicular to the separator 300, the range of the ratio of the surface density of the second coating layer 3 of the positive electrode plate 100 to the surface density of the first coating layer 2 is greater than zero and less than 0.99, and the range of the ratio of the surface density of the second coating layer 3 of the negative electrode plate 200 to the surface density of the first coating layer 2 is greater than 0.8 and less than 0.99.
[0061] In the fourth embodiment, both the positive electrode plate 100 and the negative electrode plate 200 are battery electrodes, and when the positive electrode plate 100 and the negative electrode plate 200, located on opposite sides of the same separator 300, overlap the second coating layer 3 of the positive electrode plate 100 and the second coating layer 3 of the negative electrode plate 200 in a direction perpendicular to the separator 300, 40%min{second region area of positive electrode plate 100, second region area of negative electrode plate 200} ≤ overlapping area ≤ max{second region area of positive electrode plate 100, second region area of negative electrode plate 200}, and the range of the ratio of the surface density of the second coating layer 3 of the positive electrode plate 100 to the surface density of the first coating layer 2 is greater than 0.01 and less than 0.99, and the range of the ratio of the surface density of the second coating layer 3 of the negative electrode plate 200 to the surface density of the first coating layer 2 is greater than 0.4 and less than 0.99.
[0062] The more guide channels there are, the better the rapid charging and cycling performance of the battery cell, but the more difficult it is to manufacture and the lower the capacity.
[0063] For example, S1 ≤ 600 g / m 2 Therefore, if H1 ≤ 500 μm, P1 ≤ 4.2 g / cc, and the battery electrode is the positive electrode, then S2 ≤ 400 g / m 2 Therefore, H2 ≤ 300 μm, P2 ≤ 4.0 g / cc, and if the battery electrode is the negative electrode, then S2 ≤ 400 g / m 2 Therefore, H2 ≤ 500 μm and P2 ≤ 2.0 g / cc.
[0064] The guide channels formed in the battery electrode plates of this invention have the following beneficial effects.
[0065] 1. During the battery's operation, the electrode plates expand and are subjected to force, causing the electrode liquid to be pushed out from the plates. The guide channel stores the pushed-out electrolyte, reducing the accumulation of the electrolyte around the electrode plates and preventing poor lithium deposition due to uneven reactions. This effect is particularly pronounced in large-sized power batteries.
[0066] 2. The guide channel provides an expansion space for the electrode plates, which reduces the pressure on the material due to electrode plate expansion, decreases material damage, and improves battery life.
[0067] 3. The guide channel accelerates the penetration rate of the electrode solution, improving production efficiency.
[0068] 4. The guide channel provides a storage and diffusion space for gases generated during the use of the battery cell, promoting the rapid expulsion of gases inside the battery cell to both ends of the battery cell. This solves the problem of poor contact between the electrode plates and improves the reliability of the battery.
[0069] This embodiment provides a method for manufacturing a battery electrode plate for producing the battery electrode plate described above, and includes the following steps as shown in Figure 11.
[0070] In S100, one side of the current collector 1 is divided into a first region and a second region.
[0071] In S200, the coating machine is controlled to coat the first and second regions, forming a first coating layer 2 in the first region and a second coating layer 3 in the second region, with the surface density of the first coating layer 2 being greater than that of the second coating layer 3.
[0072] The battery electrode plate manufactured by the battery electrode plate manufacturing method includes forming a first coating layer 2 and a second coating layer 3 on the side surface of the current collector 1, wherein the surface density of the first coating layer 2 is greater than that of the second coating layer 3, and the second coating layer 3 serves as a guide channel. Through the above steps, a guide channel for circulating the electrolyte during the coating process on the current collector 1 can be secured, and the manufacturing method is simple and easy to carry out, as it only requires changing the surface density of the coating layers in different regions.
[0073] In other embodiments, a trench may be provided in the current collector 1, and then a coating layer of the same thickness may be applied to form a channel at the trench location. However, providing a trench in the current collector 1 is difficult to manufacture, prone to foil breakage, and the trench may be covered and blocked by the coating layer, potentially preventing rapid transfer of the electrolyte. In other embodiments, a portion of the current collector 1 may be left uncoated, which can also create a channel.
[0074] Controlling the coating machine to coat the first and second regions includes the following steps:
[0075] In step S221, the coating machine is controlled to coat the first region with a first supply amount and the second region with a second supply amount, where the first supply amount is greater than the second supply amount.
[0076] The following two embodiments make it possible to achieve different surface densities in coating layers in different regions.
[0077] In one embodiment, the die head of the coating machine is provided with a first slurry outlet and a second slurry outlet, the coating machine is provided with a power pump for transporting the slurry, the first slurry outlet is larger than the second slurry outlet, and the coating machine is controlled to coat the first and second regions, the following steps are included.
[0078] In S2211, the pump speed of the power pump is controlled to be the same, the first region is coated with a first supply amount via the first slurry outlet, and the second region is coated with a second supply amount via the second slurry outlet.
[0079] By changing the die head of the coating machine, the coating machine can have slurry outlets of different opening sizes. For example, slurry openings of the same size may be provided, and a gasket may be placed over one of the slurry openings to reduce its size. Alternatively, a scraper capable of scraping off some of the slurry may be provided on the die head to reduce the surface density of the coating layer in the second region. This requires minimal structural changes to the die head and is easy to implement.
[0080] As shown in Figures 1 to 3, when the direction of the guide channel is the direction of the electrode plate, i.e., it is provided in the vertical direction, by adjusting the coating machine die head and adding gaskets or scrapers of different sizes, it is possible to construct second coating layers 3 of different sizes and different numbers, i.e., guide channels.
[0081] In another embodiment, the applicator is equipped with a power pump for transporting the slurry, and the applicator is controlled to coat the first and second regions, the following steps are taken:
[0082] In step S2212, the power pump is controlled to coat the first region at a first pump speed and the second region at a second pump speed, with the first pump speed being greater than the second pump speed.
[0083] In the above embodiment, it is also possible to achieve different surface densities for coating layers in different regions, and this can be achieved simply by adjusting the supply amount of the coating machine without needing to modify the die head.
[0084] As shown in Figure 5, if the direction of the guide channel is perpendicular to the electrode plate, i.e., provided laterally, the coating can be adjusted by controlling the pump speed of the coating machine. The width of the guide channel, i.e., the second coating layer 3, is adjusted by adjusting the time it takes to coat the second region at the second pump speed.
[0085] After controlling the coating machine to coat the first and second regions, the following steps are further included.
[0086] In S300, the first coating layer 2 and the second coating layer 3 are compacted such that the thickness of the second coating layer 3 is less than or equal to the thickness of the first coating layer 2, and / or the compaction density of the second coating layer 3 is less than or equal to the compaction density of the first coating layer 2. The first coating layer 2 and the second coating layer 3 may be compacted by cold pressing or hot pressing, and this application is not limited thereto.
[0087] If guide channels are provided in either of the coating layers on both sides of the current collector 1, the method for manufacturing the battery electrode plate further includes the following steps.
[0088] In S400, the other side of the current collector 1 is divided into a third region and a fourth region.
[0089] In S500, the coating machine is controlled to coat the third and fourth regions, forming a third coating layer 4 in the third region and a fourth coating layer 5 in the fourth region, with the surface density of the third coating layer 4 being greater than that of the fourth coating layer 5. After coating one side of the current collector 1, the other side is coated. The equipment and process may be the same in both cases.
Claims
1. Dividing one side of the current collector (1) into a first region and a second region, The coating machine is controlled to coat the first region and the second region, forming a first coating layer (2) in the first region and a second coating layer (3) in the second region, wherein the surface density of the first coating layer (2) is greater than that of the second coating layer (3), the first coating layer (2) and the second coating layer (3) form a coating layer, and the second coating layer (3) forms a guide channel on the coating layer, including, The guide channel is provided along at least one of the first, second, and third directions, wherein the second direction is provided at an angle to the first direction, and the first direction is perpendicular to the third direction. When multiple guide channels are provided, at least some of the guide channels are in at least one of the following states: spaced apart or intersecting, and the guide channels are located at an intermediate position on one side of the current collector (1), or at least one end of the guide channels extends to the edge of one side of the current collector (1). A method for manufacturing battery electrodes.
2. After controlling the coating machine to coat the first region and the second region, The thickness of the second coating layer (3) is to be less than or equal to the thickness of the first coating layer (2), The consolidation density of the second coating layer (3) is to be less than or equal to the consolidation density of the first coating layer (2), The thickness of the second coating layer (3) is to be less than or equal to the thickness of the first coating layer (2), and the consolidation density of the second coating layer (3) is to be less than or equal to the consolidation density of the first coating layer (2), To achieve one of the following: The method further includes compacting the first coating layer (2) and the second coating layer (3). The method according to claim 1.
3. The other side of the current collector (1) is divided into a third region and a fourth region, The coating machine is controlled to coat the third and fourth regions, forming a third coating layer (4) in the third region and a fourth coating layer (5) in the fourth region, wherein the surface density of the third coating layer (4) is greater than the surface density of the fourth coating layer (5). Further including, A method for manufacturing a battery electrode plate according to claim 1 or 2.
4. A battery electrode plate, manufactured by employing the manufacturing method of a battery electrode plate described in any one of claims 1 to 3, comprising: a current collector (1) having a first region and a second region on one side surface; a first coating layer (2) provided in the first region; and a second coating layer (3) provided in the second region, wherein the first coating layer (2) and the second coating layer (3) form a coating layer provided on one side surface of the current collector (1), the surface density of the first coating layer (2) is greater than the surface density of the second coating layer (3), and the second coating layer (3) forms a guide channel on the coating layer. Battery plate.
5. A uniform coating layer is provided on the other side surface of the current collector (1), or The other side surface of the current collector (1) is divided into a third region where a third coating layer (4) is provided and a fourth region where a fourth coating layer (5) is provided, wherein the surface density of the third coating layer (4) is greater than that of the fourth coating layer (5). The battery electrode plate according to claim 4.
6. The surface density of the third coating layer (4) is 0.6 to 1.4 times that of the first coating layer (2). The battery electrode plate according to claim 5.
7. The second coating layer (3) and the fourth coating layer (5) overlap at least partially along a direction perpendicular to the current collector (1), The battery electrode plate according to claim 5.
8. When a uniform coating layer is provided on the other side surface of the current collector (1), the range of the ratio of the projected area of the second coating layer (3) on the current collector (1) to the total surface area of the current collector (1) is 0.0001 to 0.5, or When a third coating layer (4) and a fourth coating layer (5) are provided on the other side surface of the current collector (1), the range of the ratio of the sum of the projected areas of the second coating layer (3) and the fourth coating layer (5) on the current collector (1) to the total surface area of the current collector (1) is 0.0001 to 0.
5. The battery electrode plate according to claim 5.
9. The other side surface of the current collector (1) is provided with the third coating layer (4) and the fourth coating layer (5), and the coating layers formed by the first coating layer (2) and the second coating layer (3) and the coating layers formed by the third coating layer (4) and the fourth coating layer (5) are provided symmetrically or asymmetrically on both sides of the current collector (1). The battery electrode plate according to claim 5.
10. One side of the current collector (1) is provided with one or more coating layers formed by the first coating layer (2) and the second coating layer (3) along the thickness direction. The battery electrode plate according to claim 4.
11. The first coating layer (2) and the second coating layer (3) are, The thickness of the second coating layer (3) is less than or equal to the thickness of the first coating layer (2), The consolidation density of the second coating layer (3) is less than or equal to the consolidation density of the first coating layer (2), The thickness of the second coating layer (3) is less than or equal to the thickness of the first coating layer (2), and the consolidation density of the second coating layer (3) is less than or equal to the consolidation density of the first coating layer (2), It is configured as one of the following: The battery electrode plate according to claim 4.
12. Areal density S of first coating layer (2) １ ≤600g / m ２ The thickness H of the first coating layer (2) １ The compaction density P of the first coating layer (2) is ≤ 500 μm. １ ≤ 4.2 g / cc, The areal density S of the second coating (3) ２ ≤ 400 g / m ２ and the thickness H of the second coating (3) ２ ≤ 300 μm, and the compaction density P of the second coating (3) ２ ≤ 4.0 g / cc, or the areal density S of the second coating (3) ２ ≤ 400 g / m ２ and the thickness H of the second coating (3) ２ ≤ 500 μm, and the compaction density P of the second coating (3) ２ ≤ 2.0 g / cc The battery electrode plate according to claim 11.
13. The thickness of the first coating layer (2) is greater than the thickness of the second coating layer (3), and the range of the ratio of the thickness of the second coating layer (3) to the thickness of the first coating layer (2) is greater than zero and less than 0.
995. The battery electrode plate according to claim 11.
14. The thickness of the first coating layer (2) is greater than the thickness of the second coating layer (3), and a groove (6) having an arc-shaped, rectangular, or trapezoidal cross-section is formed between the first coating layer (2) and the second coating layer (3). The battery electrode plate according to claim 11.
15. The range of the ratio of the surface density of the second coating layer (3) to the surface density of the first coating layer (2) is greater than zero and less than 0.
99. The battery electrode plate according to claim 4.
16. The coating layer is provided with one or more guide channels. The battery electrode plate according to claim 4.
17. The aforementioned coating layer is provided with a plurality of guide channels, At least some of the guide channels are spaced apart, or at least some of the guide channels are intersecting. The battery electrode plate according to claim 4.
18. One side surface of the current collector (1) is provided with a second coating layer (3). The second region is located at an intermediate position of the current collector (1), or the second region extends at least one end to the edge of the current collector (1). The battery electrode plate according to claim 16.
19. On one side of the current collector (1), a plurality of second coating layers (3) are provided at intervals, and each second coating layer (3) is provided in one second region. Multiple second regions are, Multiple second regions are located at intermediate positions of the current collector (1), At least one end of at least one second region extends to the edge of the current collector (1), At least one end of the second region extends to the edge of the current collector (1), and the remaining second region is located in the middle of the current collector (1), It is configured as one of the following: The battery electrode plate according to claim 16.
20. When the battery electrode plate is configured as the positive electrode plate (100) of a battery cell, the materials of the first coating layer (2) and the second coating layer (3) are at least one of a ternary positive electrode, an iron lithium positive electrode, and a sodium ion positive electrode. When the battery electrode plate is configured as the negative electrode plate (200) of a battery cell, the materials of the first coating layer (2) and the second coating layer (3) are at least one of the following: artificial graphite, natural graphite, hard carbon, soft carbon, silicon, and metallic materials that can form alloys with lithium sodium. The battery electrode plate according to claim 4.
21. The first coating layer (2) and the second coating layer (3) are coated on the surface of the current collector (1), or The battery electrode plate further comprises at least one intermediate coating layer provided on the surface of the current collector (1), and the first coating layer (2) and the second coating layer (3) are coated on the surface of the intermediate coating layer that is away from the current collector (1). The battery electrode plate according to claim 4.
22. The battery comprises a positive electrode plate (100), a negative electrode plate (200), and a separator (300) provided between the positive electrode plate (100) and the negative electrode plate (200), wherein at least one of the positive electrode plate (100) and the negative electrode plate (200) is a battery electrode plate according to any one of claims 4 to 21. battery.
23. When the positive electrode plate (100) is the battery electrode plate, the range of the ratio of the surface density of the second coating layer (3) to the surface density of the first coating layer (2) is greater than zero and less than 0.99, or When the negative electrode plate (200) is the battery electrode plate, the range of the ratio of the surface density of the second coating layer (3) to the surface density of the first coating layer (2) is greater than 0.8 and less than 0.99, or If the positive electrode plate (100) and the negative electrode plate (200) are both battery electrodes, and the positive electrode plate (100) and the negative electrode plate (200) located on opposite sides of the same separator (300) do not overlap in a direction perpendicular to the separator (300) between the second coating layer (3) of the positive electrode plate (100) and the second coating layer (3) of the negative electrode plate (200), then the range of the ratio of the surface density of the second coating layer (3) of the positive electrode plate (100) to the surface density of the first coating layer (2) is greater than zero and less than 0.99, and the range of the ratio of the surface density of the second coating layer (3) of the negative electrode plate (200) to the surface density of the first coating layer (2) is greater than 0.8 and less than 0.99, or If the positive electrode plate (100) and the negative electrode plate (200) are both battery electrode plates, and the positive electrode plate (100) and the negative electrode plate (200) are located on opposite sides of the same separator (300), and there is an overlap between the second coating layer (3) of the positive electrode plate (100) and the second coating layer (3) of the negative electrode plate (200) in a direction perpendicular to the separator (300), then 40% min {second region area of the positive electrode plate (100), second region area of the negative electrode plate (200) The range of the ratio of the surface density of the second coating layer (3) of the positive electrode plate (100) to the surface density of the first coating layer (2) of the positive electrode plate (100) is greater than 0.01 and less than 0.99, and the range of the ratio of the surface density of the second coating layer (3) of the negative electrode plate (200) to the surface density of the first coating layer (2) is greater than 0.4 and less than 0.
99. The battery according to claim 22.