Electrode core, electrode core production method, battery, battery device, and electric device

Abstract

This application provides an electrode core, an electrode core preparation method, a battery, a battery device, and an electrical device. The electrode core includes a positive electrode sheet, a solid electrolyte, and a negative electrode sheet. The negative electrode sheet includes a functional region and a reserve region. The reserve region is disposed along at least a portion of the outer periphery of the functional region. The positive and negative electrode sheets are stacked. Along a first direction, the reserve region protrudes from the edge of the positive electrode sheet. The negative electrode sheet has a corrugated structure in the reserve region, and the corrugated structure includes at least one pair of connected peaks and troughs. This application aims to solve the problems of internal short circuits, negative electrode sheet deformation instability, and fatigue fracture in batteries.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a core electrode, a method for preparing the core electrode, a battery, a battery device, and an electrical device. Background Technology

[0002] Solid-state batteries (SSBs), as the core of next-generation energy storage technology, have attracted much attention due to their high energy density and relatively high safety. The battery core consists of a positive electrode, a solid electrolyte, and a negative electrode. The negative electrode has an "overhang" region that extends beyond the positive electrode in a direction perpendicular to the width of the core. As a result, during battery assembly or cycling, the "overhang" region lacks corresponding support from the positive electrode, making it highly susceptible to mechanical collapse. This can lead to physical contact between the negative electrode material and the edge of the positive electrode, causing internal short circuits. Furthermore, it can cause deformation instability at the edge of the negative electrode, and even fatigue fracture. Summary of the Invention

[0003] This application provides an electrode core, an electrode core preparation method, a battery, a battery device, and an electrical device to solve the problems of internal short circuits, deformation instability of the negative electrode sheet, and fatigue fracture in the battery.

[0004] The first aspect of this application provides an electrode core, including a positive electrode, a solid electrolyte, and a negative electrode. The negative electrode includes a functional region and a reserve region. The reserve region is disposed along at least a portion of the outer periphery of the functional region. The positive electrode and the negative electrode are stacked. Along a direction perpendicular to a first direction, the reserve region protrudes from the edge of the positive electrode. The negative electrode has a corrugated structure in the reserve region. The corrugated structure includes at least a pair of connected peaks and troughs.

[0005] This application incorporates a corrugated structure in the allowance region. The crests and troughs of the corrugated structure provide support. When the electrode is under pressure, the corrugated structure preferentially bends, unfolds, or locally rebounds along the thickness direction of the electrode core, thereby providing additional deformation allowance in the edge region and dispersing local stress. The corrugated structure releases assembly pressure in advance through this elastic yielding mechanism, reducing the risk of warping, brittle collapse, or interface relaxation caused by excessive edge compression, and eliminating local stress concentration points to ensure uniform stress distribution. Simultaneously, because the crests and troughs bend in opposite directions along the thickness of the electrode core, the allowance region can maintain a relatively stable equilibrium under pressure, making it difficult for the negative electrode edge to move relative to the positive electrode edge. During long-term cycling, the corrugated structure undergoes reversible micro-deformation like a "tiny spring," thereby reversibly absorbing and dissipating interface stress and providing a continuous buffer against repeated loads caused by electrode expansion and contraction. This avoids deformation instability in the allowance region of the negative electrode and fracture due to excessive fatigue. Therefore, this application can improve the stability of the electrode edge structure, enhance assembly consistency, and reduce the risk of accidental contact between positive and negative electrode edges and the resulting short circuit, without significantly increasing additional independent components and assembly processes, thereby improving mechanical robustness, cycle life and thermal management performance.

[0006] In one possible implementation, the length of a pair of connected crests and troughs is L, and the height of the crest or trough is A, where L satisfies: 0.05mm≤L≤0.20mm, and A satisfies: 0.1mm≤A≤0.5mm.

[0007] In one possible implementation, L satisfies: 0.07mm≤L≤0.15mm, and A satisfies: 0.15mm≤A≤0.35mm.

[0008] In one possible implementation, L and A satisfy: 1.5 ≤ A / L ≤ 4.0.

[0009] In one possible implementation, an interface layer is provided on at least one side of the allowance region along a first direction; preferably, the interface layer comprises at least one of a fluoropolymer, a two-dimensional layered material, or a lubricant.

[0010] In one possible implementation, the size of the interface layer is H along the first direction, where H satisfies: 5μm≤H≤100μm;

[0011] And / or, along a direction perpendicular to the first direction, the dimension of the interface layer is W, where W satisfies: 0.5mm≤W≤3mm.

[0012] In one possible implementation, the W values ​​of the interface layers on the two outer peripheral sides of the negative electrode in the second direction are equal, and the second direction intersects the first direction; preferably, the second direction is perpendicular to the first direction.

[0013] And / or, the W values ​​of the interface layers located on the two outer peripheral sides of the negative electrode sheet in the third direction are equal, and the third direction intersects with the first direction; preferably, the third direction is perpendicular to the first direction.

[0014] In one possible implementation, the negative electrode sheet has a margin area on both outer periphery sides along the second direction, and an interface layer is provided on each margin area. The corrugated structure extends along the third direction, and the first direction, the second direction, and the third direction are perpendicular to each other.

[0015] And / or, the negative electrode sheet has a margin area on both outer periphery sides along the third direction, and an interface layer is provided on the margin area. The corrugated structure extends along the second direction, and the first direction, the second direction and the third direction are perpendicular to each other.

[0016] In one possible implementation, the size of the interface layer and the size of the margin area are equal along a direction perpendicular to the first direction.

[0017] In one possible implementation, the solid electrolyte layer is located between the functional region of the negative electrode and the positive electrode.

[0018] Alternatively, a portion of the solid electrolyte layer is located between the functional region of the negative electrode and the positive electrode, while another portion is located between the residual region of the negative electrode and the interface layer. The solid electrolyte layer located between the residual region of the negative electrode and the interface layer has a corrugated structure.

[0019] A second aspect of this application provides a method for manufacturing the aforementioned electrode core, comprising the following steps:

[0020] Obtain the precursor for the positive electrode;

[0021] Obtaining a solid electrolyte layer precursor;

[0022] Obtain a negative electrode precursor, which includes a functional region precursor and a reserve region precursor, wherein the reserve region precursor is disposed along at least a portion of the outer periphery of the functional region precursor;

[0023] The positive electrode precursor, negative electrode precursor, and solid electrolyte layer precursor are stacked to form a stacked structure, and the stacked structure is pressed to make the remaining precursor have a corrugated structure, thus obtaining the electrode core.

[0024] In one possible implementation, the laminated structure is pressed to give the remaining portion of the precursor a corrugated structure, resulting in an electrode core comprising:

[0025] Within the temperature range of 25℃ to 60℃, a pressure of 300 MPa to 500 MPa is applied to the laminated structure, and the pressure holding time is 2 min to 5 min.

[0026] In one possible implementation, the laminated structure is pressed to give the remaining area precursor a corrugated structure. Before obtaining the electrode core, the process further includes: setting a coating layer around the negative electrode precursor. The coating layer includes at least one of a fluoropolymer, a two-dimensional layered material, or a lubricant.

[0027] A third aspect of this application provides a battery, including a casing and the electrode core described above, or including an electrode core manufactured using the electrode core manufacturing method described above, wherein a receiving cavity is provided inside the casing and the electrode core is located inside the receiving cavity.

[0028] A fourth aspect of this application provides a battery device including the battery described above.

[0029] A fifth aspect of this application provides an electrical device, including an electrical appliance and the battery described above, the battery being used to power the electrical appliance; or, including the battery device described above, the battery device being used to power the electrical appliance. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] Figure 1 Exploded view of the battery provided in this application;

[0032] Figure 2 A cross-sectional view of the electrode core provided for this application;

[0033] Figure 3 A schematic diagram of a negative electrode sheet provided in this application;

[0034] Figure 4 Another structural schematic diagram of the negative electrode provided in this application;

[0035] Figure 5 This is another structural schematic diagram of the negative electrode provided in this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 100, Electrode core; 10, Positive electrode sheet; 20, Negative electrode sheet; 21, Functional area; 22, Balance area; 221, Corrugated structure; 2211, Peak; 2212, Trough; 223, Interface layer; 30, Solid electrolyte layer; 200, Shell.

[0038] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0039] Solid-state batteries (ASSBs), as the core of next-generation energy storage technology, have attracted much attention due to their high energy density and high safety. SSBs are mainly used in new energy vehicles, consumer electronics, and high-safety energy storage applications. Their cores are typically formed by stacking positive and negative electrodes sequentially and then undergoing long-term charge-discharge cycles after high-voltage assembly. However, during manufacturing and long-term operation, the structural integrity of the core, especially the electrode edge regions, faces severe challenges. These challenges mainly stem from high-voltage processes during battery assembly (such as isostatic pressing) and the unavoidable volume changes of electrode materials during charge-discharge cycles. During battery assembly, extremely high pressure is usually applied to ensure good contact between the electrodes and the solid electrolyte to reduce interfacial impedance. Under this high-pressure environment, the area where the negative electrode extends beyond the positive electrode, the so-called "overhang" region, is more prone to morphological instability under assembly compression, subsequent cycle expansion and contraction, and external loads. Furthermore, due to the lack of corresponding support from the positive electrode, mechanical collapse is very likely to occur. This collapse may cause the negative electrode material to come into physical contact with the edge of the positive electrode, thereby causing an internal short circuit. This is one of the most fatal safety hazards of solid-state batteries.

[0040] The challenges remain significant during the long-term use of batteries. Charge-discharge cycles involve the insertion and extraction of lithium ions into and out of the positive and negative electrode materials, a process that causes significant volume expansion and contraction of the electrode active materials. For example, silicon-based anodes can expand by more than 300% when fully lithium-ionized, and even graphite anodes experience a volume change of about 10%. This periodic volume change generates enormous, dynamic stress within the cell. Stress concentration is particularly pronounced at the overhang, a mechanically weak point, easily leading to fatigue fracture of current collectors (such as copper and aluminum foil) due to repeated bending, resulting in interrupted electron transport. These structural failures not only severely impair the battery's electrochemical performance, such as capacity decay and impedance increase, but also directly threaten battery safety and lifespan, becoming a key technological bottleneck restricting the commercialization of solid-state batteries.

[0041] In existing technologies, the risks of short circuits and deformation instability at the electrode edge are typically addressed by adding insulating layers, elastic filler materials, or reinforcing structures to the edge. The basic idea behind these solutions is to passively constrain the edge region through additional materials or external structures, reducing the probability of accidental contact between the positive and negative electrode edges, or by using the filler medium to absorb local compressive stress, thereby improving the stability of the electrode core during assembly. However, these solutions often rely on additional materials and processes, leading to complex manufacturing processes, narrow process windows, and difficulties in consistency control. Under high-voltage assembly conditions, the compressive stress on the edge region continuously changes. If the additional material lacks rigidity, it is prone to local collapse; if it is too flexible, it may exhibit significant migration, insufficient compaction, or interface relaxation after being compressed, making it difficult to maintain the desired shape over a long period. During charge-discharge cycles, the electrode material undergoes repeated tensile and compressive stresses due to volume changes. If there is a mismatch in mechanical properties between the additional structure and the functional area, it can easily lead to interface delamination, edge warping, structural cracking, or even loss of insulation, ultimately increasing the risk of short circuits and shortening battery life. Since the edge area simultaneously bears the dual functions of assembly compression and operational stress release, relying solely on static isolation or passive support often makes it difficult to balance long-term reliability, safety, and manufacturing cost control.

[0042] In view of this, how to maintain the structural stability of the negative electrode overhang region (i.e. the part of the negative electrode sheet that extends beyond the positive electrode sheet) under high-voltage assembly and long-term cycling conditions of solid-state batteries, and reduce the risk of edge contact and short circuit, and avoid interface delamination, current collector breakage or solid electrolyte rupture, are technical problems that urgently need to be solved.

[0043] Based on the above problems, this application provides an electrode core. The electrode core of this application has been improved compared with the traditional electrode core. The positive electrode and negative electrode are stacked. The excess area of ​​the negative electrode (i.e., the overhang area mentioned above) is provided with at least one corrugated structure. Through the bending characteristics of the corrugated structure, the edge area of ​​the negative electrode has a structural shape that is more suitable for bearing compression and cyclic deformation in the electrode core stacking state. This improves the stability of the electrode core edge without changing the overall stacking relationship, and provides a structural basis for reducing short circuit risk and improving assembly reliability.

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] This application provides a battery device and an electrical device using the battery device. The battery device provides power to some electrical devices, such as vehicles, aircraft, ferries, or computers. The battery device can be a battery module, battery pack, energy storage cabinet, or chassis (CTC integrated chassis or skateboard chassis), etc.

[0046] This application uses a vehicle as an example to illustrate the electrical device. The electrical device includes electrical equipment, and the battery device can provide electrical energy to the electrical equipment of the electrical device. In the embodiments of this application, the electrical device is a vehicle, which can be a new energy vehicle, such as a pure electric vehicle (PEV / BEV), a range-extended electric vehicle (REEV), a hybrid electric vehicle (HEV), or a fuel cell electric vehicle. The vehicle can also be any vehicle equipped with a battery.

[0047] When the battery device is a battery module, the battery module can be assembled from individual cells, and then multiple battery modules can be combined to form a battery pack.

[0048] When the battery device is a battery pack, it can consist of one or more battery modules. It typically includes battery components, connectors, a Battery Management System (BMS), a battery thermal management device, necessary structural supports, and structural protection. The BMS monitors various performance indicators of the battery pack, such as current and voltage, to ensure the pack operates within safe ranges. The battery thermal management device acts as a heat dissipation system for the battery components, effectively dissipating heat. The battery components can be connected to this thermal management device.

[0049] See Figure 1 As shown, this application also provides an electrode core 100 and a battery using the electrode core 100. The battery can be used in a battery device, or it can also be used in an electrical device to supply power to the electrical equipment of the device. The battery also includes a casing 200, in which a receiving cavity is provided, and the electrode core 100 is housed within the receiving cavity. The casing 200 is a casing encapsulation structure of a solid-state battery and can be a flexible casing, such as an aluminum-plastic film casing, which can better adapt to the deformation of the electrode core 100.

[0050] The housing 200 has a three-layer substrate structure, namely an outer nylon layer, a middle aluminum foil barrier layer, and an inner CPP heat-sealing layer. The housing 200 is formed into a recessed groove by stamping and stretching. The electrode core 100 is housed in the recessed groove. Then, the top, sides and bottom of the housing 200 are heat-sealed to seal the electrode core 100.

[0051] See Figure 2 , Figure 3 , Figure 4 and Figure 5 In some embodiments, the electrode core 100 of this application includes a positive electrode 10, a solid electrolyte layer 30, and a negative electrode 20; the negative electrode 20 includes a functional region 21 and a reserve region 22, the reserve region 22 is disposed along at least a portion of the outer periphery of the functional region 21, the positive electrode 10 and the negative electrode 20 are stacked, the reserve region 22 is disposed protruding from the edge of the positive electrode 10 along a direction perpendicular to the first direction, and the negative electrode 20 has a corrugated structure 221 in the reserve region 22, the corrugated structure 221 including at least a pair of connected peaks 2211 and valleys 2212.

[0052] It should be noted that the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20 are stacked sequentially along the first direction. The positive electrode 10 provides the positive active material and serves as one electrode layer for charge exchange. The solid electrolyte layer 30 is disposed between the positive electrode 10 and the negative electrode 20 to form electrical insulation between the positive and negative electrodes and allow ion conduction. The negative electrode 20 provides the negative active material and serves as an electrode layer opposite to the positive electrode 10.

[0053] For ease of explanation, this application introduces a three-dimensional rectangular coordinate system, see [link to relevant documentation]. Figure 1 As shown, the X-axis is parallel to the first direction. When the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20 are stacked sequentially along the first direction, the X-axis is also parallel to the thickness direction of the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20. The Y-axis is parallel to the second direction. When the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20 are stacked sequentially along the first direction, the Y-axis is also parallel to the length direction of the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20. The Z-axis is parallel to the third direction. When the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20 are stacked sequentially along the first direction, the Z-axis is also parallel to the width direction of the positive electrode 10, the solid electrolyte layer 30, and the negative electrode 20.

[0054] It is worth mentioning that the shape of the core 100 is determined by the shape or type of the battery. For example, batteries can be classified according to their external dimensions, such as cylindrical batteries, prismatic batteries, pouch batteries, and button batteries. Therefore, the core 100 can be a square, rectangular, or approximately rectangular planar stacked structure.

[0055] The negative electrode 20 of this application includes a functional region 21 and a buffer region 22. The functional region 21 is the main area of ​​the negative electrode 20 that performs the main electrochemical functions. The buffer region 22 being disposed along at least part of the outer periphery of the functional region 21 means that the buffer region 22 is disposed on the outer periphery of the functional region 21 and extends along the circumferential direction of the functional region 21. The buffer region 22 may only cover part of the outer periphery of the functional region 21, or it may cover the entire outer periphery of the functional region 21. No particular limitation is made here. After the negative electrode 20 and the positive electrode 10 are stacked, the functional region 21 of the negative electrode 20 and the positive electrode 10 are arranged facing each other in the thickness direction of the electrode core 100. At this time, the buffer region 22 is disposed protruding from the edge of the positive electrode 10 in a direction perpendicular to the first direction. That is, the buffer region 22 is the area where the edge of the negative electrode 20 extends beyond the positive electrode 10. This area serves as the overhang area of ​​the negative electrode 20.

[0056] It is understood that the smallest unit of the corrugated structure 221 is the connected crests 2211 and troughs 2212, both of which are parabolic structures, with the crests 2211 and troughs 2212 curving in opposite directions. The corrugated structure 221 of this application includes at least one pair of such crests 2211 and troughs 2212.

[0057] This application incorporates a corrugated structure 221 in the allowance region 22. The crests 2211 and troughs 2212 of the corrugated structure 221 provide support. When the electrode is compressed, the corrugated structure 221 can preferentially bend, unfold, or locally rebound along the thickness direction of the electrode core 100, thereby providing additional deformation allowance in the edge region and dispersing local stress. The corrugated structure 221 releases assembly pressure in advance through this elastic yielding mechanism, reducing the risk of warping, brittle collapse, or interface relaxation caused by excessive edge compression, and eliminating local stress concentration points, ensuring uniform stress. The distribution is such that, simultaneously, due to the opposite bending of the peaks 2211 and troughs 2212 in the thickness of the core 100, the margin region 22 can maintain a relatively stable equilibrium state under pressure, making it difficult for the edge of the negative electrode 20 to move relative to the edge of the positive electrode 10. During long-term cycling, the corrugated structure 221 undergoes reversible micro-deformation like a "tiny spring," thereby reversibly absorbing and dissipating interfacial stress and providing a continuous buffer against repeated loads caused by electrode expansion and contraction. This avoids deformation instability in the margin region 22 of the negative electrode 20 and fracture due to excessive fatigue. Therefore, this application can improve the stability of the edge structure of the core 100, enhance assembly consistency, and reduce the risk of accidental contact between the positive and negative electrode edges and the resulting short circuit without significantly increasing additional independent components and assembly processes, thus improving mechanical robustness, cycle life, and thermal management performance.

[0058] See Figure 2 and Figure 3As shown, in some embodiments, the length of a pair of connected peaks 2211 and valleys 2212 is L, and the height of peak 2211 or valley 2212 is A, where L satisfies: 0.05mm≤L≤0.20mm, and A satisfies: 0.1mm≤A≤0.5mm.

[0059] It should be noted that the allowance region 22 of this application can be provided with multiple corrugated structures 221, which are connected to each other. Each corrugated structure 221 has at least one pair of connected peaks 2211 and valleys 2212. The pair of connected peaks 2211 and valleys 2212 constitutes the minimum structure of the corrugated structure 221. Along the extension direction of the peaks 2211 and valleys 2212, the distance from the end of the peak 2211 away from the valley 2212 to the point where the two are connected is the length of the peak 2211, and the distance from the end of the valley 2212 away from the peak 2211 to the point where the two are connected is the length of the valley 2212. The sum of the lengths of the peaks 2211 and valleys 2212 is the length between the two connected peaks 2211 and valleys 2212, which is denoted as L. Along the curvature of crest 2211 and trough 2212, the distance between the end of crest 2211 away from trough 2212 and the point where the two connect is the height of crest 2211, and the distance between the end of trough 2212 away from crest 2211 and the point where the two connect is the height of trough 2212. This height is set as A. It is worth mentioning that the height and length of the crests 2211 and troughs 2212 can be equal, in which case the corrugated structure 221 is a regular-shaped corrugation; or, the length of the crests 2211 and troughs 2212 are equal, but the heights of the crests 2211 and troughs 2212 can be equal or unequal; or, the lengths of the crests 2211 and troughs 2212 are equal or unequal, but the heights of the crests 2211 and troughs 2212 are equal; or, the lengths of the crests 2211 and troughs 2212 are unequal, and the heights of the crests 2211 and troughs 2212 are unequal, in which case the corrugated structure 221 is an irregular-shaped corrugation. The specific settings need to be determined based on the actual situation, and no special limitations are made here.

[0060] In practical applications, the probability of differences in size between the crests 2211 and troughs 2212 of the corrugated structure 221 is relatively high. Therefore, L in this application can be defined as an average value, that is, L is the average length between multiple pairs of connected crests 2211 and troughs 2212. For example, the average length L can be a range of 0.05mm, 0.07mm, 0.09mm, 0.11mm, 0.13mm, 0.15mm, 0.17mm, 0.20mm, or any two of these. It is understood that the average length L can be any value between 0.07mm and 0.17mm; or, the average length L can be any value between 0.09mm and 0.15mm; or, the average length L can be any value between 0.11mm and 0.15mm.

[0061] In this application, A can be defined as an average value, that is, A is the average height of the multiple peaks 2211 and multiple troughs 2212. For example, the average height A can be a range of 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, or any combination thereof. Furthermore, it is understood that the average height A can be any value between 0.15mm and 0.45mm; or, the average height A can be any value between 0.2mm and 0.4mm; or, the average height A can be any value between 0.25mm and 0.35mm.

[0062] In some embodiments, the average length L can be any value between 0.07 mm and 0.15 mm. The average height A can be any value between 0.15 mm and 0.35 mm.

[0063] The geometric parameters of the corrugated structure 221 directly affect the compressive strength and deformation tolerance of the edge region. The function of this structure is to enable the margin region 22 to preferentially dissipate local stress through the bending deformation of the crests 2211 and troughs 2212 when subjected to thickness loads caused by stacking, encapsulation clamping, or charge-discharge cycles. This reduces the compression concentration of the negative electrode 20 edge on the positive electrode 10 and the solid electrolyte layer 30, and reduces the risk of edge warping, collapse, and local contact. When the electrode core 100 is subjected to external compression during assembly, after the positive electrode 10 and negative electrode 20 are stacked in sequence, the portion of the negative electrode 20's excess area 22 extending beyond the edge of the positive electrode 10 first bears the boundary constraint load. The individual corrugated structure 221 then generates synergistic bending in the thickness direction, causing the stress originally concentrated at the edge to disperse along the crests and troughs. In subsequent charge and discharge cycles, the electrode material repeatedly expands and contracts with volume changes. The crests 2211 and troughs 2212 can provide buffer space for this change through elastic bending and local undulations, reducing the rigid compression between the excess area 22 and adjacent layers, and suppressing the continuous collapse or delamination of the edge region. Since the average length L and the average height A of the crests 2211 and troughs 2212 are limited to the above range, the corrugated structure 221 has stronger support, resilience and stress buffering capacity. When it is subjected to deformation, it can maintain appropriate flexibility and recovery capacity, and is not prone to excessive flattening or excessive warping. This helps to further reduce the short circuit probability at the edge of the negative electrode 20, and improve the structural consistency and safety reliability of the electrode core 100 in high voltage assembly and long-term cycling. It also avoids the problem of fatigue fracture caused by excessive bending at the margin area 22, and improves cycle life.

[0064] It should be noted that, as mentioned above, a pair of wave crests 2211 and wave troughs 2212 connected end to end constitute the smallest structural unit of the corrugated structure 221. The margin region 22 has multiple such smallest structural units, which are connected end to end. The L mentioned above is the average length of the smallest structural unit, and A is the average length of the wave crests 2211 and wave troughs 2212.

[0065] The measurement methods for L and A are as follows: When measuring the average length L of these minimum structural units and the average height A of the peaks 2211 and troughs 2212, the pole core 100 needs to be transferred to a measuring tool with magnification, such as a stereomicroscope or metallurgical microscope; then, under the magnification of the measuring tool, at least five groups of minimum structural units are selected in the margin area 22 for measurement. It should be noted that there are two ways to select the minimum structural unit. The first way is to select multiple consecutive groups of minimum structural units, calculate the total length and the total height of the peaks 2211 and troughs 2212, and then calculate the average length using the ratio of the total length to the number of selected minimum structural units. The average height A is calculated using the ratio of the total height to the total number of peaks 2211 and troughs 2212. The selection position is random and not limited, and can be selected at any position in the margin area 22. The second way is to select multiple groups of minimum structural units at different positions in the margin area 22. Each group contains one minimum structural unit or contains multiple consecutive minimum structural units, ensuring that the total number of groups of minimum structural units is not less than five.

[0066] In some embodiments, L and A satisfy: 1.5 ≤ A / L ≤ 4.0. For example, the ratio of average height A to average length L can be a range of 1.5, 2, 2.5, 3, 3.5, 4.0 or any two of these.

[0067] The ratio of L to A constrains the geometry of a single corrugated structure 221 on the margin region 22. When the ratio satisfies 1.5 ≤ A / L ≤ 4.0, it indicates that the corrugated structure 221 has a suitable aspect ratio, enabling it to provide sufficient deformation space in the thickness direction under pressure while maintaining the necessary geometric support capacity. This avoids the corrugations being too flat to absorb stress or too tall to cause instability and collapse during assembly compression and cyclic expansion and contraction. This ratio corresponds to the dimensional coordination condition of the local corrugated units at the edge of the margin region 22. It does not change the overall arrangement of the corrugated structure 221 at the edge of the negative electrode sheet 20, but optimizes its matching degree with the stacking state of the electrode core 100 by controlling the morphological parameters of the crests 2211 and troughs 2212. When the A / L ratio is relatively large, the undulations of the peaks 2211 and troughs 2212 are more pronounced, providing stronger deformation absorption capacity under external compressive loads and electrode volume changes. When the A / L ratio is relatively small, the peaks 2211 and troughs 2212 tend to be gentler, resulting in higher structural rigidity, making them suitable for use in applications requiring high edge support. During operation, when the electrode core 100 is subjected to assembly compressive force or expansion stress during subsequent charging and discharging, the peaks 2211 and troughs 2212 will exhibit bending and local bulging responses along the thickness direction. By utilizing the predetermined aspect ratio, the compression energy is dispersed and released, allowing the edge margin area 22 to absorb local stress while maintaining its isolation function. When the load decreases or is released, the peaks 2211 and troughs 2212 can maintain or partially restore their original proportional relationship under the combined action of the material's elastic recovery and structural constraints, thereby continuously maintaining the morphological stability of the edge region and reducing the probability of accidental contact between the edges of the positive electrode 10 and the negative electrode 20. Therefore, this ratio limit helps to balance structural compliance and anti-collapse capability under long-term cycling and high-pressure assembly conditions, thereby improving the stability of the core 100 edge, assembly reliability and safety of use.

[0068] In some embodiments, the allowance region 22 is located at the periphery of the functional region 21, and the corrugated structure 221 is arranged circumferentially along the functional region 21 in the allowance region 22. The corrugated structure 221 forms undulating units in the allowance region 22 along the thickness direction of the cell, which is used to construct a continuous buffer deformation region. Essentially, it provides circumferentially distributed local buckling capability on the allowance region 22 through periodic undulations. The corrugated structure 221 is located at least part of the outer periphery of the functional region 21, so that the functional region 21 can obtain corresponding stress sharing and deformation release paths around its periphery or at its local edges, thereby reducing the local stress peak in the edge region during the pressure assembly of the electrode core 100 and subsequent charge-discharge cycles.

[0069] In terms of morphology, the crests 2211 and troughs 2212 of the corrugated structure 221 can be arc-shaped segments, bent segments, S-shaped segments, or approximately wave-shaped segments, so that controlled elastic deformation can preferentially occur when subjected to compressive force.

[0070] In some embodiments, an interface layer 223 is provided on at least one side of the allowance region 22 along a first direction. The interface layer 223 is lubricating and comprises a low-adhesion or low-friction material, or is induced to form by a raw material comprising such a material. The electrode core 100 has multiple layers of negative electrode sheets 20 and multiple layers of positive electrode sheets 10. At least one positive electrode sheet 10 and a solid electrolyte are present between each two adjacent negative electrode sheets 20. Since the allowance region 22 is formed at the edge of the negative electrode sheet 20 and protrudes from the edge of the positive electrode sheet 10, there is a gap between the allowance regions 22 of adjacent negative electrode sheets 20 before the negative electrode sheet 20, the positive electrode sheet 10 and the solid electrolyte are stacked and a high voltage is applied. Interface layer 223 is located within the gap. The interface layer 223 located between two adjacent allowance regions 22 can consist of only one interface layer 223 provided on one of the allowance regions 22, or it can be provided on both adjacent allowance regions 22, with the interface layers 223 positioned opposite each other and their end faces abutting each other. By providing interface layer 223, and utilizing the lubricity of interface layer 223, it can both support the two adjacent allowance regions 22 and increase the possibility of sliding between the two adjacent allowance regions 22 in the thickness direction of the pole core 100 when pressure is applied to the allowance regions 22, thereby facilitating the maintenance of the corrugated structure 221 in the allowance region 22.

[0071] See Figure 2 , Figure 4 and Figure 5As shown, in some embodiments, the dimension H of the interface layer 223 along the first direction satisfies: 5μm ≤ H ≤ 100μm. The dimension H of the interface layer 223 in the first direction is the thickness of the interface layer 223. For example, the thickness H of the interface layer 223 can be a range of 5μm, 10μm, 20μm, 25μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, or any combination thereof. It is understood that the thickness H of the interface layer 223 can be any value between 10μm and 90μm; or, the thickness H of the interface layer 223 can be any value between 20μm and 80μm; or, the thickness H of the interface layer 223 can be any value between 30μm and 70μm; or, the thickness H of the interface layer 223 can be any value between 40μm and 60μm. By setting the thickness of the interface layer 223, it can be ensured that the thickness of the interface layer 223 will not exceed the gap between two adjacent margin areas 22, and it can provide support between the two adjacent margin areas 22. In addition, by setting the thickness of the interface layer 223 within the above range, it is also beneficial for the average wavelength of the corrugated structure 221 and the average height of the peaks 2211 and the valleys 2212 to reach the above range.

[0072] In some embodiments, the dimension W of the interface layer 223 along a direction perpendicular to the first direction satisfies: 0.5mm ≤ W ≤ 3mm. The dimension W of the interface layer 223 in the direction perpendicular to the first direction is the width of the interface layer 223. For example, the width W of the interface layer 223 can be a range of 0.5mm, 0.75mm, 1mm, 1.25mm, 1.5mm, 1.75mm, 2mm, 2.25mm, 2.5mm, 2.75mm, 3mm, or any combination thereof. It is understood that the width W of the interface layer 223 can be any value between 0.75mm and 2.75mm; or, the width W of the interface layer 223 can be any value between 1mm and 2.5mm; or, the width W of the interface layer 223 can be any value between 1.25mm and 2.25mm; or, the width W of the interface layer 223 can be any value between 1.5mm and 2mm. By setting the width of the interface layer 223, it is ensured that the width of the interface layer 223 will not exceed the width of the allowance area 22, and it is beneficial to form a corrugated structure 221 within the aforementioned size range on the allowance area 22. Preferably, the width of the interface layer 223 and the width of the allowance area 22 are equal, in which case the edge of the interface layer 223 is flush with the edge of the allowance area 22.

[0073] In some embodiments, the negative electrode 20 has a margin region 22 on both outer peripheral sides along the second direction, and an interface layer 223 is provided on each margin region 22. The corrugated structure 221 extends along the third direction, and the first direction, the second direction, and the third direction are perpendicular to each other. And / or, the negative electrode 20 has a margin region 22 on both outer peripheral sides along the third direction, and an interface layer 223 is provided on each margin region 22. The corrugated structure 221 extends along the second direction, and the first direction, the second direction, and the third direction are perpendicular to each other.

[0074] The negative electrode 20 is a square electrode, such as a square or rectangular electrode, and has four sides. The negative electrode 20 may have a margin area 22 on some of its outer periphery, or all of its outer periphery may have a margin area 22. Specifically, the negative electrode 20 may have a margin area 22 on both outer periphery sides in the second direction, but not on the two outer periphery sides in the third direction; or, the negative electrode 20 may not have a margin area 22 on either of its two outer periphery sides in the second direction, but has a margin area 22 on the two outer periphery sides in the third direction; or, the negative electrode 20 may have a margin area 22 on both outer periphery sides in the second direction and a margin area 22 on both outer periphery sides in the third direction. In this case, the margin areas 22 on adjacent sides are connected.

[0075] In some embodiments, the width W of the interface layer 223 located on both outer peripheral sides of the negative electrode 20 in the second direction is equal; and / or, the width W of the interface layer 223 located on both outer peripheral sides of the negative electrode 20 in the third direction is equal. In this way, the width W of the interface layer 223 on opposite sides of the negative electrode 20 is equal, and equal width means that the width of the interface layer 223 at each position along the extension direction of the side is equal. By setting the width of the interface layer 223 on opposite sides to be equal, the uniformity of the corrugated structure 221 on the margin region 22 on opposite sides can be ensured, thereby ensuring the uniformity of the buffer stress.

[0076] It should be noted that the width of the interface layer 223 located on the outer periphery of the negative electrode 20 in the second direction and the width of the interface layer 223 located on the outer periphery of the negative electrode 20 in the third direction can be equal or unequal.

[0077] It is understandable that due to process deviations or measurement errors, the deviation of W in the interface layer 223 on the upper side is less than or equal to 2%, which is considered equal. Deviation = (larger value - smaller value) / larger value.

[0078] In some embodiments, the interface layer 223 includes a fluoropolymer, which refers to a high molecular weight polymer whose main chain or side chain contains carbon-fluorine bonds (C–F), formed by fluorine-substituted hydrocarbon polymers containing some or all hydrogen atoms, such as PTFE (polytetrafluoroethylene) or FEP (fluorinated ethylene propylene); or, the interface layer may include a two-dimensional layered material, which refers to an inorganic or organic material with nanoscale thickness (single atom / few atomic layers), planar sheet morphology, and weak van der Waals forces between layers, such as molybdenum disulfide, boron nitride (h-BN); or, the interface layer includes a lubricant, which refers to a substance that can reduce the coefficient of friction, reduce wear, improve interface wettability, prevent adhesion, and inhibit interface side reactions. The lubricant in this application may be semi-solid or solid, such as solid lubricant or silicone-based lubricant; or, the interface layer 223 includes at least one of a fluoropolymer, a two-dimensional layered material, and a lubricant.

[0079] In some embodiments, the solid electrolyte layer 30 is located between the functional region 21 of the negative electrode 20 and the positive electrode 10; or, a portion of the solid electrolyte layer 30 is located between the functional region 21 of the negative electrode 20 and the positive electrode 10, and another portion of the solid electrolyte layer 30 is located between the residual region 22 of the negative electrode 20 and the interface layer 223, and the solid electrolyte layer 30 located between the residual region 22 of the negative electrode 20 and the interface layer 223 has a corrugated structure 221.

[0080] The solid electrolyte is located between the positive electrode 10 and the negative electrode 20. Because the edge of the negative electrode 20 has a protruding margin region 22 extending beyond the positive electrode 10, the solid electrolyte can be disposed only between the functional region 21 of the negative electrode 20 and the positive electrode 10, without being disposed on the margin region 22. In this case, the interface layer 223 is directly disposed on the margin region 22. Alternatively, the solid electrolyte can be partially disposed between the functional region 21 of the negative electrode 20 and the positive electrode 10, with another portion extending into the margin region 22 of the negative electrode 20. In this case, the solid electrolyte is located between the interface layer 223 and the margin region 22.

[0081] When the solid electrolyte is located between the negative electrode's residual area and the positive electrode, if the residual area lacks a corrugated structure, delamination can easily occur at the interface between the residual area of ​​the negative electrode and the solid electrolyte, disrupting the ion transport channels. The solid electrolyte itself may also crack due to the inability to withstand localized stress. By incorporating a corrugated structure, the structure provides support, buffering the stress on the solid electrolyte, preventing delamination between the negative electrode and the solid electrolyte, and preventing the solid electrolyte from cracking.

[0082] This application embodiment also provides a method for manufacturing the aforementioned electrode core, including the following steps:

[0083] S100, Obtain the precursor for the positive electrode;

[0084] S200, Obtain the solid electrolyte layer precursor;

[0085] S300. Obtain a negative electrode precursor, which includes a functional region precursor and a reserve region precursor, wherein the reserve region precursor is disposed along at least a portion of the outer periphery of the functional region precursor.

[0086] S400: The positive electrode precursor, negative electrode precursor, and solid electrolyte layer precursor are stacked to form a stacked structure, and the stacked structure is pressed so that the negative electrode precursor has a corrugated structure in the margin area.

[0087] Understandably, the difference between the positive electrode precursor, negative electrode precursor, and solid electrolyte layer precursor and the positive electrode, negative electrode, and solid electrolyte layer lies in whether or not they have undergone pressing treatment. This pressing treatment is a routine pressing process in cell manufacturing and does not change the material properties of each layer.

[0088] The positive electrode precursor can be composed of a metal current collector supporting a positive electrode active material and a solid electrolyte composite layer, and the negative electrode precursor can be composed of a metal current collector supporting a negative electrode active material and a solid electrolyte composite layer. It should be noted that the metal current collector of the positive electrode precursor can include, for example, at least one of aluminum foil or nickel foil, and the positive electrode active material includes at least one composite oxide of lithium with cobalt, manganese, nickel, or combinations thereof. Specifically, it can include at least one of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, nickel-cobalt-manganese ternary materials, nickel-cobalt-aluminum ternary materials, lithium iron phosphate (LFP), lithium nickel manganese oxide, lithium-rich manganese-based materials, etc.; the metal current collector of the negative electrode includes at least one of copper foil, nickel foam, and copper foam, and the negative electrode active material includes at least one of graphite, hard carbon, soft carbon, mesophase carbon microspheres, silicon-based negative electrode materials (mainly including silicon suboxide and silicon-carbon negative electrodes), tin-based negative electrode materials (mainly including tin and tin alloys), etc.

[0089] The stacked positive electrode precursor is located in the functional area of ​​the negative electrode precursor. That is, in the first direction, the positive electrode precursor is positioned directly opposite the functional area precursor of the negative electrode precursor. Furthermore, along the first direction, the orthogonal projection of the positive electrode precursor toward the negative electrode precursor and the functional area precursor of the negative electrode precursor coincide, so as to ensure that the spare area precursor of the negative electrode precursor extends beyond the edge of the positive electrode precursor.

[0090] Specifically, a mold with a corrugated structure can be used to press the edges of the negative electrode sheet to form a corrugated structure. The pressing process can be performed on the edges of a single negative electrode sheet before stacking, or the negative electrode edges can be pressed after the cell stacking is completed.

[0091] In some embodiments, the laminated structure is pressed to give the precursor of the mass region a corrugated structure, resulting in an electrode core comprising:

[0092] Within the temperature range of 25℃ to 60℃, a pressure of 300 MPa to 500 MPa is applied to the laminated structure, and the pressure holding time is 2 min to 5 min.

[0093] The laminated structure is processed by hot pressing. The hot isostatic pressing temperature can be 25℃, 60℃, or any temperature between 25℃ and 60℃. The pressure applied to the laminated structure can be any value between 300MPa, 500MPa, or 300MPa-500MPa, and the holding time can be any value between 2min, 5min, or 2min-5min, depending on the actual requirements, and no special limitation is made here.

[0094] Preferably, the hot pressing process described above is an isostatic pressing process.

[0095] Preferably, based on the above steps, an additional step is added, such as forming a coating layer around the negative electrode precursor. This coating layer comprises at least one of a fluoropolymer, a two-dimensional layered material, or a lubricant. Under hot pressing, this coating layer not only induces and promotes the formation of a corrugated structure but also reduces the formation of an interface layer, thus stabilizing / fixing the already formed corrugated structure.

[0096] The present application will be further described below through specific embodiments.

[0097] Example 1

[0098] 1. Preparation of positive electrode sheet

[0099] Active material NCM (nickel-cobalt-manganese ternary cathode material) (the molar ratio of NCM used in this application is nickel:cobalt:manganese = 8:1:1), sulfide solid electrolyte (Li6PS5Cl), and binder (polyvinylidene fluoride, PVDF) are mixed in anisole at a mass ratio of 80:15:2:3 to form a homogeneous slurry. The slurry is coated onto an aluminum foil current collector and dried to obtain a cathode precursor. This cathode precursor is dried and rolled to obtain the cathode. The cathode thickness is 100 μm (including the current collector).

[0100] The positive electrode sheet is cut into films with a length of 100 mm and a width of 80 mm.

[0101] 2. Preparation of negative electrode sheet

[0102] A silicon-carbon composite anode material (SiOx-C), a sulfide solid electrolyte (Li6PS5Cl), conductive carbon, and a binder (styrene-butadiene rubber SBR) were mixed in anisole at a mass ratio of 75:20:2:3 to form a homogeneous slurry. The slurry was coated onto a copper foil current collector and dried to obtain the anode precursor. This anode precursor was then dried and rolled to obtain the anode sheet. The anode sheet thickness was 120 μm (including the current collector).

[0103] 3. Preparation of composite negative electrode sheet

[0104] A sulfide solid electrolyte powder (Li6PS5Cl) is mixed with a binder (such as PVDF) at a mass ratio of 95:5, and a solvent (such as NMP) is added to form a slurry. This slurry is then coated onto the negative electrode material layer of the negative electrode sheet to form a composite negative electrode sheet. The slurry containing the sulfide solid electrolyte powder and binder, after drying, serves as a precursor for the solid electrolyte layer.

[0105] 4. Composite negative electrode die-cutting: Based on the width of the allowance area, the die-cutting length is the positive electrode die-cutting length plus twice the allowance area width, and the die-cutting width is the positive electrode die-cutting width plus twice the allowance area width. There is an allowance area on all four sides of the negative electrode. The allowance area width along the length direction of the negative electrode (second direction) is 3.0 mm, and the allowance area width along the width direction of the negative electrode (third direction) is 2.0 mm.

[0106] 5. Ripple Formation

[0107] The negative electrode sheet excess area is pressed using a mold with a corrugated structure. The mold corrugations are uniform, with L being 0.1 mm and A being 0.25 mm.

[0108] 6. Battery Assembly

[0109] The electrodes are stacked in the order of "composite negative electrode, positive electrode, composite negative electrode," ending with the composite negative electrode, ensuring that the positive electrode is centered and aligned, and that the excess area of ​​the negative electrode extends evenly. The stacked body is then placed in a vacuum bag for pressing. Under the set pressure (300 MPa), temperature (25°C), and holding time (3 min), the main functional area of ​​the electrode core densifies and shrinks, applying in-plane compressive stress to the edge excess area, inducing the formation of an adaptive corrugated structure.

[0110] 7. Packaging

[0111] The isostatically pressed electrode cores are then encapsulated to complete the fabrication of the all-solid-state battery.

[0112] To verify the technical effects of this application, the following embodiments and comparative examples were designed. All embodiments and comparative examples used the same NCM811 / silicon-carbon / sulfide electrolyte material system and the above preparation method.

[0113] Comparative Example 1:

[0114] The difference from Example 1 is that no interface layer is set in the margin area, and the margin area does not have a corrugated structure. The other conditions are the same as in Example 1.

[0115] Example 2

[0116] The difference from Example 1 is that a coating layer consisting of polytetrafluoroethylene (PTFE) (DuPont MP130) and PFPE (perfluoropolyether) (Chemours, Krytox GPL 105) (mass ratio PTFE:PFPE=70:30) is precisely coated on both sides of the negative electrode blank area (depending on the stacking design) using spraying or screen printing. After drying, an interface layer is formed with a width W of 2 mm. The thickness H of the interface layer is 30 μm by controlling the wet film thickness of the coating layer.

[0117] Examples 3-20: The difference from Example 2 is that the average wavelength L of the corrugated structure, the average height A of the peaks and troughs, and the ratio of the average wavelength L of the corrugated structure to the average height A of the peaks and troughs are limited by controlling the ratio of the coating material and the process conditions. See Tables 1 and 2 for details. Except for the differences shown in Tables 1 and 2, the other conditions are the same as in Example 2.

[0118] The solid-state batteries of Examples 1-20 and Comparative Example 1 were tested using the following procedure, and the results are shown in Table 1:

[0119] Short circuit test: At 25℃, the solid-state battery is charged to 4.2V at a constant current of 1C, left to stand for 30 minutes, and then discharged to 2.5V at a constant current of 1C. This cycle is repeated once, and the discharge capacity of the first cycle is recorded. The battery with the lowest discharge capacity is the short circuit. Based on 100 batteries, the short circuit rate (%) = (number of short-circuited batteries / 100) × 100%.

[0120] Cyclic performance test: At 25℃, the solid-state battery is charged to 4.2V at a constant current of 1C, rested for 30 minutes, and then discharged to 2.5V at a constant current of 1C. This cycle is repeated 2000 times. Capacity retention rate (%) = (C2000 / C1)×100%, where C1 is the discharge capacity of one cycle and C2000 is the discharge capacity of 2000 cycles.

[0121] Table 1

[0122]

[0123] Table 2

[0124]

[0125] As can be seen from Tables 1 and 2 above, Comparative Example 1, without a corrugated structure, had a battery short-circuit rate of 10.8%, and a capacity retention rate of 65% after 2000 cycles. Compared to Comparative Example 1, the residual area in Example 1 of this application has a corrugated structure, which significantly improves the capacity retention rate and reduces the short-circuit rate during battery cycling. During cycle testing, the battery short-circuit rate decreased, and the capacity retention rate was greater than or equal to 70%.

[0126] Referring to Tables 1 and 2, compared to Example 1, Examples 2-19 impose restrictions on the parameters of the corrugated structure. Table 2 shows that Examples 2-16 limit the values ​​of L and A for the corrugated structure. Specifically, in Examples 2-13, L satisfies: 0.05mm ≤ L ≤ 0.20mm, and A satisfies: 0.1mm ≤ A ≤ 0.5mm. When L and A meet these ranges, the short-circuit rate of the battery decreases, and the battery capacity retention rate increases. However, Examples 14-16 show that when at least one of the parameters L and A of the corrugated structure does not meet the above ranges, the short-circuit rate of the battery is between the preferred range mentioned above and the short-circuit rate without a corrugated structure, and the battery capacity retention rate is less than 80%. The battery short-circuit rate relatively increases, and the battery capacity retention rate decreases. Therefore, based on the corrugated structure in the margin area, the preferred values ​​for L in the corrugated structure are: 0.05mm ≤ L ≤ 0.20mm, and the preferred values ​​for A are: 0.1mm ≤ A ≤ 0.5mm.

[0127] Furthermore, referring to Tables 1 and 2, and from Examples 2-13 in Table 2, it can be seen that, based on the preferred values ​​of L (0.05mm ≤ L ≤ 0.20mm) and A (0.1mm ≤ A ≤ 0.5mm), when A / L satisfies 1.5 ≤ A / L ≤ 4.0, the battery has a lower short-circuit rate and a higher capacity retention rate. However, as shown in Examples 17 and 18, both excessively large and small A / L will lead to a relative increase in the short-circuit rate and a decrease in the capacity retention rate during battery cycling. Therefore, the preferred A / L is 1.5 ≤ A / L ≤ 4.0.

[0128] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. An electrode core, characterized in that, include: Positive electrode sheet (10); Solid electrolyte layer (30); and The negative electrode (20) includes a functional area (21) and a margin area (22). The margin area (22) is disposed along at least part of the outer periphery of the functional area (21). The positive electrode (10) and the negative electrode (20) are stacked together. The margin area (22) protrudes from the edge of the positive electrode (10) along a direction perpendicular to a first direction. The negative electrode (20) has a corrugated structure (221) in the margin area (22). The corrugated structure (221) includes at least one pair of connected peaks (2211) and valleys (2212).

2. The electrode core according to claim 1, characterized in that, The length of a pair of connected crests and troughs is L, and the height of the crest (2211) or the trough (2212) is A. The L satisfies: 0.05mm≤L≤0.20mm, and the A satisfies: 0.1mm≤A≤0.5mm.

3. The electrode core according to claim 2, characterized in that, The L satisfies: 0.07mm≤L≤0.15mm, and the A satisfies: 0.15mm≤A≤0.35mm.

4. The electrode core according to claim 2, characterized in that, The L and A satisfy: 1.5≤A / L≤4.

0.

5. The electrode core according to any one of claims 1-4, characterized in that, Along the first direction, at least one side of the allowance region (22) is provided with an interface layer (223); preferably, the interface layer (223) includes at least one of a fluoropolymer, a two-dimensional layered material or a lubricant.

6. The electrode core according to claim 5, characterized in that, Along the first direction, the size of the interface layer (223) is H, wherein H satisfies: 5μm≤H≤100μm; And / or, along a direction perpendicular to the first direction, the size of the interface layer (223) is W, wherein W satisfies: 0.5mm≤W≤3mm.

7. The electrode core according to claim 6, characterized in that, The W values ​​of the interface layer (223) located on the two outer peripheral sides of the negative electrode (20) in the second direction are all equal, and the second direction intersects the first direction; preferably, the second direction is perpendicular to the first direction; And / or, the W values ​​of the interface layer (223) located on the two outer peripheral sides of the negative electrode (20) in the third direction are all equal, and the third direction intersects with the first direction; preferably, the third direction is perpendicular to the first direction.

8. The electrode core according to claim 5, characterized in that, The negative electrode sheet (20) has a margin area (22) on both outer periphery sides along the second direction, and the margin area (22) is provided with an interface layer (223). The corrugated structure (221) extends along the third direction, and the first direction, the second direction and the third direction are perpendicular to each other. And / or, the negative electrode (20) is provided with the margin area (22) on both outer periphery sides along the third direction, and the margin area (22) is provided with the interface layer (223), the corrugated structure (221) extends along the second direction, and the first direction, the second direction and the third direction are perpendicular to each other.

9. The electrode core according to claim 5 or 6, characterized in that, Along a direction perpendicular to the first direction, the size of the interface layer (223) is equal to the size of the margin area (22).

10. The electrode core according to claim 5 or 6, characterized in that, The solid electrolyte layer (30) is located between the functional area (21) of the negative electrode (20) and the positive electrode (10); Alternatively, a portion of the solid electrolyte layer (30) is located between the functional region (21) of the negative electrode (20) and the positive electrode (10), and another portion of the solid electrolyte layer (30) is located between the residual region (22) of the negative electrode (20) and the interface layer (223). The solid electrolyte layer (30) located between the residual region (22) of the negative electrode (20) and the interface layer (223) has the corrugated structure (221).

11. A method for manufacturing an electrode core as described in any one of claims 1-10, characterized in that, Includes the following steps: Obtain the precursor for the positive electrode; Obtaining a solid electrolyte layer precursor; Obtain a negative electrode precursor, the negative electrode precursor including a functional region precursor and a reserve region precursor, the reserve region precursor being disposed along at least a portion of the outer periphery of the functional region precursor; The positive electrode precursor, the negative electrode precursor, and the solid electrolyte layer precursor are stacked to form a stacked structure, and the stacked structure is pressed to make the remaining precursor have a corrugated structure, thus obtaining the electrode core.

12. The method for manufacturing an electrode core according to claim 11, characterized in that, The laminated structure is pressed to give the remaining portion of the precursor a corrugated structure, resulting in the electrode core comprising: Within the temperature range of 25℃ to 60℃, a pressure of 300MPa to 500MPa is applied to the laminated structure, and the pressure holding time is 2min to 5min.

13. The method for manufacturing an electrode core according to claim 11, characterized in that, Before obtaining the electrode core, the process of pressing the stacked structure to make the remaining area precursor have a corrugated structure includes: setting a coating layer around the negative electrode precursor, the coating layer comprising at least one of a fluoropolymer, a two-dimensional layered material, or a lubricant.

14. A battery, characterized in that, The device includes a housing (200) and an electrode core (100) as described in any one of claims 1-10, or, includes an electrode core (100) manufactured using the electrode core manufacturing method described in any one of claims 11-13, wherein the housing (200) has a receiving cavity and the electrode core (100) is located within the receiving cavity.

15. A battery device, characterized in that, Includes the battery as described in claim 14.

16. An electrical appliance, characterized in that, The device includes an electrical appliance and the battery of claim 14, the battery being used to power the electrical appliance; or, the device includes the battery assembly of claim 15, the battery assembly being used to power the electrical appliance.

Images