Electrode components, fabrication methods, batteries and energy storage devices

Abstract

This application provides an electrode assembly, a method for fabricating the electrode assembly, a battery, and an energy storage device. The electrode assembly includes a positive electrode unit, a negative electrode unit, and an ion transport unit. The positive electrode unit includes a positive current collector and a positive active material layer. The negative electrode unit includes a negative current collector and a negative active material layer. The ion transport unit is disposed between the positive electrode unit and the negative electrode unit and includes a separator and at least two ion conduction pillars. The separator is located between the positive active material layer and the negative active material layer, and is used to physically isolate the positive electrode unit and the negative electrode unit. The ion conduction pillars extend from the separator to both sides and are embedded in the positive active material layer and the negative active material layer, respectively. The ion conduction pillars are configured to have transport channels for ion transport and to prevent the positive active material in the positive active material layer and the negative active material in the negative active material layer from making electronic contact through the ion conduction pillars.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to an electrode assembly, a method for preparing the electrode assembly, a battery, and an energy storage device. Background Technology

[0002] Currently, electrode manufacturing for battery structures (such as lithium-ion batteries) generally employs winding or stacking processes. The electrode sheet fabrication process typically involves a series of complex steps, including stirring, coating, drying, rolling, and slitting. These steps suffer from problems such as long process flows, large equipment investments, high production costs, and extremely high requirements for process control precision, resulting in poor product consistency and reduced yield.

[0003] More importantly, traditional processes impose fundamental limitations on the thickness of the active material layer on the electrode sheet. For example, thick coatings are prone to cracking, difficult to dry, and roll forming is difficult to ensure uniform density. Therefore, traditional processes are unable to manufacture thick active material layers. Even if the manufacturing problem of thick active material layers is solved through process improvements, increasing the thickness of the active material layer will prolong the solid-state diffusion path of lithium ions within the active material, leading to increased internal resistance, intensified polarization, and lithium plating on the negative electrode, which will seriously impair the battery's rate performance and cycle life. Summary of the Invention

[0004] In view of the above problems, this application provides an electrode assembly, a method for preparing the electrode assembly, a battery, and an energy storage device.

[0005] In a first aspect, this application provides an electrode assembly comprising a positive electrode unit, a negative electrode unit, and an ion transport unit. The positive electrode unit includes a positive current collector and a positive active material layer. The negative electrode unit includes a negative current collector and a negative active material layer. The ion transport unit is disposed between the positive electrode unit and the negative electrode unit, and includes a separator and at least two ion conduction pillars. The separator is located between the positive active material layer and the negative active material layer, serving to physically isolate the positive electrode unit and the negative electrode unit. The ion conduction pillars extend from the separator to both sides and are respectively embedded within the positive active material layer and the negative active material layer. The ion conduction pillars are configured to have transport channels for ion transport and to prevent electronic contact between the positive active material in the positive active material layer and the negative active material in the negative active material layer through the ion conduction pillars.

[0006] The electrode assembly of this application constructs a penetrating liquid-phase ion transport channel within a thick electrode assembly by setting ion conduction pillars extending to both sides and embedded within the positive and negative electrode active material layers on the separator. The ion conduction pillars are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar, thereby reducing ion transport impedance and solving the problem of increased internal resistance in thick electrode assemblies. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly is more uniform, avoiding lithium plating caused by localized lithium deficiency. This ensures that the battery with the thick electrode assembly possesses excellent rate performance and cycle life.

[0007] As an optional technical solution of this application, the thickness T1 of the positive electrode unit satisfies: 0.5mm≤T1≤15mm.

[0008] In the electrode assembly of this application, the thickness T1 of the positive electrode unit satisfies: 0.5mm≤T1≤15mm, which makes the thickness of the positive electrode active material layer several to tens of times that of traditional electrodes (usually not exceeding 200 micrometers), thereby accommodating more positive electrode active material in the same battery volume and improving the volumetric energy density of the battery.

[0009] As an optional technical solution of this application, the thickness T2 of the negative electrode unit satisfies: 0.5mm≤T2≤15mm.

[0010] In the electrode assembly of this application, the thickness T2 of the negative electrode unit satisfies: 0.5mm≤T2≤15mm, which makes the thickness of the negative electrode active material layer several to tens of times that of traditional electrodes (usually not exceeding 200 micrometers), thereby accommodating more negative electrode active material in the same battery volume and improving the volumetric energy density of the battery.

[0011] As an optional technical solution of this application, at least one of the positive electrode current collector and the negative electrode current collector includes a current collector plate and a plurality of current collection structures extending from the current collector plate into the corresponding active material layer, wherein the current collection structures are made of the same material as the current collector plate.

[0012] This application expands the electron collection network from a two-dimensional plane to a three-dimensional network by setting a current-collecting structure extending into the interior of the active material layer. This allows electrons to be captured by the current-collecting structure near the active material layer and directly conducted to the current collector plate. The electron transmission distance is reduced from the full thickness of the electrode assembly to the short distance from the active material particles to the nearest current-collecting structure, thereby significantly reducing electron transmission impedance and accelerating electron transfer rate. Furthermore, the current-collecting structure and the current collector plate are made of the same material, ensuring no contact resistance or electrochemical corrosion risk at the interface, further improving electron conduction efficiency. Simultaneously, the current-collecting structure forms a mechanical interlock with the active material during subsequent pressure molding, enhancing the structural integrity of the thick electrode assembly and solving the process defects of cracking and peeling in thick coatings.

[0013] As an optional technical solution of this application, in the height direction from the positive electrode unit to the negative electrode unit, the current collection structure is spaced apart from the separator plate and from the ion conduction column extending into the corresponding active material layer.

[0014] This application ensures that the current collector structure contacts the active material in the active material layer only, responsible for collecting and conducting electrons, by separating the current collector structure from the isolation plate and from the ion conduction column. The ion conduction column contacts the electrolyte in the active material layer only, responsible for transporting ions. The two do not interfere with each other, forming a dual-channel cooperative transport network for electrons and ions. Electrons are rapidly conducted to the current collector plate within the active material layer through the current collector structure, while ions rapidly migrate to the opposite electrode within the active material layer through the ion conduction column. The two are independent yet cooperative, ensuring efficient electron and ion transport and fundamentally avoiding the risk of internal short circuits caused by contact between the current collector structure and the ion conduction column.

[0015] As an optional technical solution of this application, the flow area S of the current collection structure is in the range of 0.00785 mm. 2 ≤S≤3.1416mm 2 .

[0016] This application limits the current-carrying area of ​​the current collector structure to the range of 0.00785 mm² to 3.1416 mm², which ensures that the current collector structure has sufficient current-carrying capacity to support the high-rate charging and discharging requirements of the thick electrode assembly, and also ensures that a good mechanical interlock can be formed between the current collector structure and the active material, while achieving an optimal balance between energy density and electronic conductivity.

[0017] As an optional technical solution of this application, the current collection structure is upright in the active material layer, the current collection structure includes a positive current collection structure and a negative current collection structure, the active material layer includes a positive active material layer and a negative active material layer, the length of the positive current collection structure is less than or equal to the thickness of the positive active material layer, and the length of the negative current collection structure is less than or equal to the thickness of the negative active material layer.

[0018] The electrode assembly of this application features an upright current collector structure within the active material layer. This upright arrangement, perpendicular to the plane of the current collector plate, minimizes the electron transport path within the current collector structure. Electrons enter the current collector structure from the active material particles and are directly conducted to the current collector plate along the axial direction of the current collector structure (i.e., the thickness direction of the active material layer), without needing to traverse a tortuous path. This significantly reduces electron transport impedance and accelerates electron transfer. Furthermore, since the length of the current collector structure is less than or equal to the thickness of the corresponding active material layer, it prevents the current collector structure from piercing the isolation plate.

[0019] As an optional technical solution of this application, the current collection structure is curved in the active material layer.

[0020] In the electrode assembly of this application, the current collector structure is configured in a curved shape within the active material layer. The curved current collector structure occupies a larger space within the active material layer, resulting in more contact points and a larger contact surface with the surrounding active material particles, thereby reducing contact resistance and improving electron collection efficiency. Moreover, the curved shape creates a mechanical interlocking effect similar to that between steel bars and concrete in concrete. When the active material expands or contracts in volume during charging and discharging, the curved current collector structure can be anchored in the active material layer through its curved shape, effectively suppressing the relative displacement between the active material and the current collector and preventing electrical contact failure caused by volume changes.

[0021] As an optional technical solution of this application, the ion conduction column includes a core and an insulating layer that completely covers the outer surface of the core. The core has a porous structure. The insulating layer is made of the same material as the isolation plate.

[0022] The electrode assembly of this application uses a porous core as the ion conduction column, and fully encapsulates the outer surface of the core with an insulating layer made of the same material as the separator. This maintains ion conduction within the conduction column while forming a complete electronic barrier on the outer surface of the core. The porous core has an interconnected network of pores. When filled with electrolyte, these pores form a three-dimensional interconnected liquid-phase ion transport path, allowing lithium ions to migrate rapidly within the network. This reduces the effective ion diffusion distance from the full thickness of the active material layer to the micrometer-level distance between the active material particles and the outer wall of the ion conduction column, thus lowering the ion transport impedance. Simultaneously, the insulating layer uses the same material as the separator, ensuring consistent insulation performance and ion permeability, and avoiding the risk of short circuits between the positive and negative electrode materials that might occur when the ion conduction column provides a rapid ion channel.

[0023] As an optional technical solution of this application, the ion conduction column has a cavity with closed ends inside, and the material of the peripheral wall of the cavity is the same as the material of the isolation plate.

[0024] The electrode assembly of this application forms a closed cavity inside the ion conduction column, with the cavity's peripheral wall made of the same material as the separator, creating a liquid-phase ion channel isolated from the outside. The cavity's peripheral wall uses the same porous material as the separator; the microporous structure of the cavity's peripheral wall, filled with electrolyte, forms a liquid-phase ion transport path, allowing lithium ions to freely migrate between the cavity and the active material layer. This reduces the effective ion diffusion distance from the full thickness of the active material layer to the micrometer-level distance between the active material particles and the outer wall of the ion conduction column, lowering ion transport impedance. Simultaneously, the peripheral wall uses the same insulating material as the separator, physically isolating the electrolyte inside the cavity from the active material outside the ion conduction column, preventing electronic contact between the positive and negative electrode active materials through the cavity, and avoiding the risk of short circuits between the positive and negative electrode materials that might occur when the ion conduction column provides a fast ion channel.

[0025] As an optional technical solution of this application, the ion conduction column includes a core and an insulating separator. The core has a hollow cavity or a porous structure. The insulating separator is disposed at the boundary between the positive electrode active material layer and the negative electrode active material layer of the ion conduction column, and the insulating separator is made of the same material as the separator plate.

[0026] The electrode assembly of this application sets the ion conduction column as a core with a hollow cavity or porous structure, and sets an insulating isolation sheet of the same material as the isolation plate at the boundary between the ion conduction column and the positive and negative electrode active material layers. This keeps the part of the conduction column extending into the electrode exposed with a porous structure, blocking the electron path only at the critical interface position. This reduces the amount of insulating material used while ensuring short circuit prevention.

[0027] As an optional technical solution of this application, the isolation plate and the ion conduction column are integrally formed.

[0028] The electrode assembly of this application integrates the separator plate and the ion conduction column into a single molded structure, making the ion transport unit a complete component. This integrated structure eliminates assembly errors between the separator plate and the conduction column, ensuring precise and controllable relative positioning of each conduction column relative to the separator plate. It also reduces assembly steps, resolving the short-circuit risk caused by assembly deviations and the extremely high precision requirements for process control inherent in traditional split structures, thereby improving production efficiency and yield.

[0029] As an optional technical solution of this application, the electrode assembly has a multi-layer structure, including at least two positive electrode units and at least two negative electrode units, wherein the positive electrode units and the negative electrode units are stacked alternately, and the ion transport units are disposed between adjacent units.

[0030] The electrode assembly of this application forms a multilayer structure by alternately stacking at least two positive electrode units and at least two negative electrode units, with ion transport units placed between adjacent units. This multilayer structure design increases the battery's capacity and voltage by increasing the number of layers, meeting the needs of various application scenarios.

[0031] Secondly, this application provides a method for preparing the electrode assembly described in any of the above embodiments. The preparation method includes: We provide positive electrode current collector preforms and negative electrode current collector preforms; The positive electrode active material is combined with the positive electrode current collector preform to form a positive electrode unit, the positive electrode unit comprising a positive electrode current collector and a positive electrode active material layer; The negative electrode active material is combined with the negative electrode current collector preform to form a negative electrode unit, the negative electrode unit comprising a negative electrode current collector and a negative electrode active material layer; An ion transport unit is provided, the ion transport unit including an isolation plate and a plurality of ion conduction columns protruding from the isolation plate to both sides; The ion transport unit is disposed between the positive electrode unit and the negative electrode unit, and the two ends of the ion conduction column are respectively embedded inside the positive electrode active material layer and the negative electrode active material layer to obtain the electrode assembly. The ion-conducting column is configured to have a transmission channel for ion transport and to prevent the positive active material in the positive electrode active material layer from making electronic contact with the negative active material in the negative electrode active material layer through the ion-conducting column.

[0032] The preparation method of this application combines a positive electrode active material with a positive electrode current collector preform to form a positive electrode unit, and combines a negative electrode active material with a negative electrode current collector preform to form a negative electrode unit. An ion transport unit is then placed between the positive and negative electrode units, with both ends of the ion conduction column embedded within the positive and negative electrode active material layers, achieving integrated molding of the electrode assembly. This method replaces the traditional multi-step processes of stirring, coating, drying, rolling, and slitting with a filling and pressurizing process, solving the problems of long process flow, large equipment investment, high production cost, and low yield in traditional electrode manufacturing. It significantly simplifies the process, reduces energy consumption, and improves production efficiency.

[0033] As an optional technical solution of this application, the positive electrode current collector includes a positive electrode current collector plate and at least two positive electrode current collector preforms extending from the positive electrode current collector plate; the step of combining the positive electrode active material with the positive electrode current collector preforms to form a positive electrode unit includes: Place the positive electrode current collector preform into the processing tank; A positive electrode active material is added to the processing tank, and the positive electrode active material is filled between the positive electrode current collector structure preforms of the positive electrode current collector preform; and Pressurize the filled structure to cause the positive electrode current collector preform to bend or remain upright, to solidify the positive electrode active material into the positive electrode active material layer, and to form at least two first mounting channels in the positive electrode active material layer to form the positive electrode unit.

[0034] The preparation method of this application simultaneously achieves the construction of the positive electrode electron network, the forming of the positive electrode unit, and the prefabrication of the first installation channel by applying pressure once. This not only solves the problems of easy cracking, difficult drying, and difficulty in ensuring density uniformity in traditional processes, but also provides a first installation channel for guiding the precise embedding of the ion conduction column into the positive electrode active material.

[0035] As an optional technical solution of this application, the negative electrode current collector includes a negative electrode current collector plate and at least two negative electrode current collector preforms extending from the negative electrode current collector plate; the step of combining the negative electrode active material with the negative electrode current collector preforms to form a negative electrode unit includes: Place the negative electrode current collector preform into the processing tank; A negative electrode active material is added to the processing tank, and the negative electrode active material is filled between the negative electrode current collector structure preforms of the negative electrode current collector preform; and Pressurize the filled structure to cause the negative electrode current collector preform to bend or remain upright, to solidify the negative electrode active material into the negative electrode active material layer, and to form at least two second mounting channels in the negative electrode active material layer to form the negative electrode unit.

[0036] The preparation method of this application realizes the construction of the three-dimensional electron network of the negative electrode, the molding of the negative electrode unit, and the prefabrication of the second mounting channel simultaneously by applying pressure once. It not only solves the problems of easy cracking of thick coating, difficulty in drying, and difficulty in ensuring density uniformity by rolling in traditional processes, but also provides a second mounting channel for guiding the precise embedding of the ion conduction column into the negative electrode active material.

[0037] As an optional technical solution of this application, the step of disposing the ion transport unit between the positive electrode unit and the negative electrode unit, and embedding both ends of the ion conduction column into the positive electrode active material layer and the negative electrode active material layer respectively, includes: The ion transport unit is disposed between the positive electrode unit and the negative electrode unit, and the two ends of the ion conduction column are respectively embedded inside the first mounting channel and the second mounting channel.

[0038] The preparation method of this application achieves precise alignment and assembly of the ion conduction column with the positive and negative electrode active material layers by placing the ion transport unit between the positive electrode unit and the negative electrode unit, and embedding the two ends of the ion conduction column into the first and second mounting channels respectively. This avoids short circuits or ion channel failures caused by assembly deviations during the embedding process, and improves assembly accuracy and product yield.

[0039] Thirdly, this application provides a battery. The battery includes the electrode assembly described in any of the above embodiments.

[0040] In the battery of this application, the electrode assembly constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly by setting ion conduction pillars extending to both sides of the separator and embedded within the positive and negative electrode active material layers respectively. The ion conduction pillars are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar, thereby reducing ion transport impedance and solving the problem of increased internal resistance in thick electrode assemblies. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly is more uniform, avoiding lithium plating caused by localized lithium deficiency. This ensures that the battery with the thick electrode assembly possesses excellent rate performance and cycle life.

[0041] Fourthly, this application provides an energy storage device. The energy storage device includes a housing and a battery as described in any of the above embodiments, the battery being housed within the housing.

[0042] In the energy storage device of this application, the electrode assembly constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly by setting ion conduction pillars extending to both sides and embedded within the positive and negative electrode active material layers on the separator plate. The ion conduction pillars are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar, thereby reducing ion transport impedance and solving the problem of increased internal resistance in thick electrode assemblies. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly is more uniform, avoiding lithium plating caused by localized lithium deficiency, thus ensuring that the battery with the thick electrode assembly possesses good rate performance and cycle life.

[0043] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0044] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a three-dimensional assembly schematic diagram of the electrode assembly according to some embodiments of this application; Figure 2 for Figure 1 An exploded three-dimensional view of a portion of the structure of the electrode assembly shown. Figure 3 for Figure 1 An exploded three-dimensional view of the electrode assembly shown. Figure 4 for Figure 1 An exploded three-dimensional view of the electrode assembly shown from another perspective; Figure 5 for Figure 1 A top view of the electrode assembly shown; Figure 6 for Figure 5 The diagram shows a cross-sectional view of the electrode assembly along line VI-VI and a larger view at point A. Figure 7 In other embodiments, the electrode assembly is along with... Figure 5 A schematic diagram of the cross-section obtained by the same cross-section line between the centerline VI and VI, and an enlarged schematic diagram of point B; Figure 8Figure (a) is an enlarged schematic diagram of the electrode assembly corresponding to point A or B in some other embodiments, and Figure (b) is an enlarged schematic diagram of the electrode assembly corresponding to point A or B in some other embodiments. Figure 9 This is an enlarged schematic diagram of the electrode assembly corresponding to point B in some other embodiments; Figure 10 This is a three-dimensional assembly diagram of the electrode assembly according to some embodiments; Figure 11 This is a flowchart illustrating a method for fabricating an electrode assembly according to some embodiments of this application; Figure 12 for Figure 11 The flowchart of the method for fabricating the electrode assembly shown is a process for forming the negative electrode unit; Figure 13 for Figure 11 The flowchart of the process for forming the positive electrode unit in the preparation method of the electrode assembly shown; Figure 14 This is a schematic diagram of placing the positive electrode current collector preform into the processing tank; Figure 15 This is a schematic diagram of the positive electrode current collector preform being housed in the processing tank; Figure 16 This is a schematic diagram of adding positive electrode active material into a processing tank containing a positive electrode current collector preform; Figure 17 This is a schematic diagram showing the positive electrode active material being filled into the positive electrode current collector preform. Figures 18 to 20 This is a schematic diagram of applying pressure to the filled structure to cause the positive electrode current collector preform to bend or remain upright in order to form a positive electrode unit. Figure 21 yes Figure 20 The diagram shows an exploded view of the positive electrode unit; Figure 22 This is a schematic diagram illustrating the principle of forming a negative electrode unit in the preparation method of an electrode assembly according to some embodiments of this application; Figure 23 Is adopted Figure 22 A three-dimensional schematic diagram of the negative electrode unit formed by the principle shown; Figure 24 yes Figure 23 The diagram shows an exploded view of the negative electrode unit; Figure 25 This is a perspective view of a battery according to some embodiments of this application; Figure 26 This is a perspective view of a battery pack according to some embodiments of this application; Figure 27 This is a schematic diagram of the energy storage system according to some embodiments of this application; Figure 28 This is a schematic diagram of the structure of an electrical device according to some embodiments of this application.

[0045] The reference numerals in the detailed embodiments are as follows: 10,000 electrical equipment; Energy storage system 1000; high-voltage cable 2000; first power conversion device 3000; second power conversion device 4000; battery pack 100A; battery cabinet 300A, battery 100; 10 housing, 11 housing body, 13 top cover, 15 explosion-proof valve; Electrode assembly 30, positive electrode unit 31, positive electrode current collector 311, positive electrode current collector plate 3111, positive electrode current collector structure 3113, positive electrode current collector preform 311a, positive electrode current collector structure preform 3113a, positive electrode active material 313a, positive electrode active material layer 313, first mounting channel 3130, negative electrode unit 33, negative electrode current collector 331, negative electrode current collector plate 3311, negative electrode current collector structure 3313, negative electrode active material 333a, negative electrode active material layer 333, second mounting channel 3330, negative electrode current collector preform 331a, negative electrode current collector structure preform 3313a, ion transport unit 35, isolation plate 351, ion conduction column 353, cavity 3530, core 3531, insulating isolation layer 3533, insulating isolation sheet 3535; 200 outer shell, 201 box body, 203 cover; 300A battery cabinet; 40 processing slot; 50 pressurizing device, 51 pressure head, 511 pressure head body, 513 column, 53 connector, Z in height direction. Detailed Implementation

[0046] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0047] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0048] In this document, the term "implementation" means that a specific feature, structure, or characteristic described in connection with an implementation may be included in at least one implementation of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same implementation, nor is it a separate or alternative implementation mutually exclusive with other implementations. It will be explicitly and implicitly understood by those skilled in the art that the implementations described herein can be combined with other implementations.

[0049] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, the simultaneous existence of mounting protrusions and mounting holes, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following associated objects have an "or" relationship.

[0050] In the description of the embodiments of this application, the technical terms "center", "first", "second", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0051] In the description of the embodiments of this application, unless otherwise explicitly specified and limited, the technical terms such as "installation", "connection", "linking", and "fixing" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components.

[0052] Currently, electrode manufacturing for battery structures (such as lithium-ion batteries) generally employs winding or stacking processes. The electrode sheet fabrication process typically involves a series of complex steps, including stirring, coating, drying, rolling, and slitting. These steps suffer from long process flows, high equipment investment, high production costs, and extremely high requirements for process control precision, leading to poor product consistency and reduced yield. More importantly, traditional processes fundamentally limit the thickness of the active material layer on the electrode sheet. For example, thick coatings are prone to cracking, difficult to dry, and roll forming is difficult to ensure density uniformity. Therefore, traditional processes struggle to manufacture thicker active material layers. Even if process improvements solve the problem of manufacturing thick active material layers, increasing the thickness of the active material layer prolongs the solid-state diffusion path of lithium ions within the active material, leading to increased internal resistance, intensified polarization, and lithium plating on the negative electrode, severely impairing the battery's rate performance and cycle life. To address this issue, this application provides an electrode assembly 30 ( Figures 1 to 10 (as shown), preparation method of electrode assembly ( Figures 11 to 24 (as shown), battery 100 ( Figure 25 As shown), battery pack 100A ( Figure 26 As shown), energy storage system 1000 ( Figure 27 (as shown) and electrical equipment 10000 ( Figure 28 (As shown).

[0053] Please see Figures 1 to 4 In a first aspect, this application provides an electrode assembly 30, which includes a positive electrode unit 31, a negative electrode unit 33, and an ion transport unit 35. The positive electrode unit 31 includes a positive current collector 311 and a positive active material layer 313. The negative electrode unit 33 includes a negative current collector 331 and a negative active material layer 333. The ion transport unit 35 is disposed between the positive electrode unit 31 and the negative electrode unit 33, and includes a separator 351 and at least two ion conduction pillars 353. The separator 351 is located between the positive active material layer 313 and the negative active material layer 333, serving to physically isolate the positive electrode unit 31 and the negative electrode unit 33, while allowing ions to pass through. Each ion conduction pillar 353 extends from the separator 351 to both sides and is embedded within the positive active material layer 313 and the negative active material layer 333, respectively. The ion conduction pillar 353 is configured to have a transport channel for ion transport and to prevent the positive active material 313a (…) in the positive active material layer 313 from passing through. Figure 16 (as shown) and the negative electrode active material 333a in the negative electrode active material layer 333 ( Figure 22 (As shown) Electron contact occurs through ion conduction column 353.

[0054] Electrode assembly 30 is a core component of electrochemical energy storage devices, such as lithium-ion batteries, sodium-ion batteries, and supercapacitors. It converts external electrical energy into chemical energy and stores it in the electrode material during charging, and converts the stored chemical energy back into electrical energy for external output during discharging. An electrode assembly 30 includes at least one positive electrode unit 31, one negative electrode unit 33, and an ion transport unit 35 disposed between the positive electrode unit 31 and the negative electrode unit 33. Multiple electrode assemblies 30 can be combined in series or parallel to form a battery 100 with a higher voltage or larger capacity. Figure 25 (as shown) or supercapacitors.

[0055] The positive electrode unit 31 is the structural part of the electrode assembly 30 used to extract lithium ions during charging and insert lithium ions during discharging. In the positive electrode unit 31, the positive electrode current collector 311 is usually made of aluminum foil or carbon-coated aluminum foil. The positive electrode current collector 311 provides an electron conduction path for the positive electrode active material layer 313 and uniformly distributes electrons input from the external circuit to the entire positive electrode active material layer 313. The positive electrode active material layer 313 is formed on the surface of the positive electrode current collector 311, and common materials include, but are not limited to, lithium cobalt oxide, lithium iron phosphate, and lithium nickel cobalt manganese oxide.

[0056] The negative electrode unit 33 is the structural part of the electrode assembly 30 used for inserting lithium ions during charging and extracting lithium ions during discharging. In the negative electrode unit 33, the negative electrode current collector 331 is typically made of copper foil or porous copper foil. The negative electrode current collector 331 provides an electron conduction path for the negative electrode active material layer 333 and collects the electrons generated by the negative electrode active material layer 333 before transmitting them to the external circuit. The negative electrode active material layer 333 is formed on the surface of the negative electrode current collector 331, and common materials include, but are not limited to, graphite, silicon-carbon composite materials, and lithium titanate.

[0057] The separator 351 is located between the positive electrode active material layer 313 and the negative electrode active material layer 333. The separator 351 physically separates the positive electrode unit 31 and the negative electrode unit 33, preventing direct contact between them and causing a short circuit. Simultaneously, it allows lithium ions to freely pass between the positive electrode active material layer 313 and the negative electrode active material layer 333. The separator 351 can be made of a polyolefin porous membrane (such as polyethylene or polypropylene), a ceramic-coated separator, or a cellulose separator. The separator 351 has a large number of micropores inside, which, when filled with electrolyte, form liquid-phase channels for ion conduction.

[0058] Ion conduction columns 353 extend from the separator 351 to both sides, with one end embedded inside the positive electrode active material layer 313 and the other end embedded inside the negative electrode active material layer 333. There are at least two ion conduction columns 353, and multiple ion conduction columns 353 can be distributed in an array, grid, or irregular pattern within the plane of the separator 351 according to design requirements. The ion conduction columns 353 are configured to have transport channels for ion transport. These transport channels can be hollow cavities extending along the axial direction of the ion conduction column 353, or interconnected porous structures distributed within the ion conduction column 353. After the transport channels are filled with electrolyte, lithium ions can migrate in the liquid phase within the transport channels. The ion conduction column 353 is also configured to prevent the positive electrode active material 313a and the negative electrode active material 333a from making electronic contact through the ion conduction column 353. This function can be achieved by providing an insulating layer on the surface of the ion conduction column 353, or by providing an insulating sheet only at the interface between the positive electrode active material layer 313 and the negative electrode active material layer 333 on the ion conduction column 353.

[0059] like Figure 1 As shown, in the assembled state of the electrode assembly 30, the positive electrode unit 31, the ion transport unit 35, and the negative electrode unit 33 are stacked sequentially. A separator 351 separates the positive electrode active material layer 313 from the negative electrode active material layer 333. The two ends of the ion conduction pillar 353 penetrate into the positive electrode active material layer 313 and the negative electrode active material layer 333, respectively. The positive electrode current collector 311 is located on one of the outermost sides of the entire electrode assembly 30 in the height direction Z (the direction from the positive electrode unit 31 to the negative electrode unit 33, or vice versa). The negative electrode current collector 331 is located on the other outermost side in the height direction Z. An external circuit is electrically connected to the electrode assembly 30 through the positive electrode current collector 311 and the negative electrode current collector 331.

[0060] The electrode assembly 30 of this application constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly 30 by setting ion conduction pillars 353 extending to both sides and embedded within the positive and negative electrode active material layers 333 on the separator 351. The ion conduction pillars 353 are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers 333 to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar 353, thereby reducing ion transport impedance and solving the problem of increased internal resistance in the thick electrode assembly 30. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly 30 is more uniform, avoiding lithium plating caused by localized lithium deficiency, thus ensuring that the battery 100 with the thick electrode assembly 30 has good rate performance and cycle life.

[0061] Please see Figure 2As an optional technical solution of this application, the thickness T1 of the positive electrode unit 31 satisfies: 0.5mm≤T1≤15mm.

[0062] The thickness T1 of the positive electrode unit 31 refers to the total thickness of the positive electrode current collector 311 and the positive electrode active material layer 313 after being superimposed. In this technical solution, the thickness T1 of the positive electrode unit 31 can be any value among 0.5mm, 0.8mm, 1.0mm, 1.5mm, 2.0mm, 3.0mm, 5.0mm, 8.0mm, 10.0mm, 12.0mm and 15.0mm, or any value between any two adjacent values.

[0063] When the thickness T1 of the positive electrode unit 31 is less than 0.5 mm, although the ion transport path is shorter and the rate performance is better, the loading of the positive electrode active material 313a is too low, and the amount of electricity that the electrode assembly 30 can store per unit area is limited, making it difficult to improve the volumetric energy density of the battery 100. When the thickness T1 of the positive electrode unit 31 is greater than 15 mm, the excessively thick positive electrode unit 31 requires higher requirements for the manufacturing process (the pressure molding process of this application) during preparation, and is prone to defects such as uneven density and internal microcracks, affecting the structural integrity and long-term cycle stability of the electrode assembly 30.

[0064] In the electrode assembly 30 of this application, the thickness T1 of the positive electrode unit 31 satisfies: 0.5mm≤T1≤15mm, making the thickness of the positive electrode active material layer 313 several to tens of times that of conventional electrodes (usually not exceeding 200 micrometers), thereby accommodating more positive electrode active material 313a in the same battery volume 100. Figure 16 As shown in the figure, the volumetric energy density of the battery 100 is improved. Moreover, due to the presence of the ion transport unit 35, the ion transport impedance is reduced, solving the problem of increased internal resistance of the thick electrode assembly 30. At the same time, since the ion supply can meet the reaction requirements in a timely manner, the current distribution inside the electrode assembly 30 is more uniform, avoiding lithium plating caused by local lithium deficiency, thereby ensuring that the battery 100 with the thick electrode assembly 30 has good rate performance and cycle life.

[0065] Please continue reading. Figure 2 As an optional technical solution of this application, the thickness T2 of the negative electrode unit 33 satisfies: 0.5mm≤T2≤15mm.

[0066] The thickness T2 of the negative electrode unit 33 refers to the total thickness of the negative electrode current collector 331 and the negative electrode active material layer 333 after being superimposed. In this technical solution, the thickness T2 of the negative electrode unit 33 can be any value among 0.5mm, 0.8mm, 1.0mm, 1.5mm, 2.0mm, 3.0mm, 5.0mm, 8.0mm, 10.0mm, 12.0mm and 15.0mm, or any value between any two adjacent values.

[0067] When the thickness T2 of the negative electrode unit 33 is less than 0.5 mm, although the ion transport path is shorter and the rate performance is better, the loading of the negative electrode active material 333a is too low, and the amount of energy that can be stored per unit area of ​​the electrode assembly 30 is limited, making it difficult to improve the volumetric energy density of the battery 100. When the thickness T2 of the negative electrode unit 33 is greater than 15 mm, the excessively thick negative electrode unit 33 requires higher requirements for the manufacturing process (the pressure molding process of this application) during preparation, and is prone to defects such as uneven density and internal cracks, affecting the cycle stability and safety of the battery 100.

[0068] In the electrode assembly 30 of this application, the thickness T2 of the negative electrode unit 33 satisfies: 0.5mm≤T2≤15mm, making the thickness of the negative electrode active material layer 333 several to tens of times that of conventional electrodes (usually not exceeding 200 micrometers), thereby accommodating more negative electrode active material 333a in the same battery volume 100. Figure 22 As shown in the figure, the volumetric energy density of the battery 100 is improved. Moreover, due to the presence of the ion transport unit 35, the ion transport impedance is reduced, solving the problem of increased internal resistance of the thick electrode assembly 30. At the same time, since the ion supply can meet the reaction requirements in a timely manner, the current distribution inside the electrode assembly 30 is more uniform, avoiding lithium plating caused by local lithium deficiency, thereby ensuring that the battery 100 with the thick electrode assembly 30 has good rate performance and cycle life.

[0069] Please see Figure 3 and Figure 4 As an optional technical solution of this application, at least one of the positive electrode current collector and the negative electrode current collector includes a current collector plate and a plurality of current collection structures extending from the current collector plate into the corresponding active material layer, wherein the current collection structures are made of the same material as the current collector plate.

[0070] In some embodiments, the current collector structures are distributed in an upright columnar shape within the active material layer, with the length of the current collector structure being less than or equal to the thickness of the corresponding active material layer. By configuring the current collector structures in an upright columnar distribution within the active material layer, the electrode assembly achieves a directional arrangement of the current collector structures perpendicular to the plane of the current collector plate. This upright columnar distribution minimizes the electron transport path within the current collector structure—electrons enter the current collector structure from the active material particles and are directly conducted to the current collector plate along the axial direction (i.e., the thickness direction) of the current collector structure, without needing to traverse a tortuous path. This minimizes electron transport impedance and accelerates the electron transfer rate. Furthermore, since the length of the current collector structure is less than or equal to the thickness of the corresponding active material layer, it prevents the current collector structure from piercing the isolation plate.

[0071] In other embodiments, the current collector structure is curved within the active material layer. The curved current collector structure occupies a larger space within the active material layer, resulting in more contact points and a larger contact surface with the surrounding active material particles. This reduces contact resistance and improves electron collection efficiency. Furthermore, the curved shape creates a mechanical interlocking effect similar to that between steel bars and concrete in concrete. When the active material expands or contracts in volume during charging and discharging, the curved current collector structure can be anchored within the active material layer through its curved shape, effectively suppressing the relative displacement between the active material and the current collector and preventing electrical contact failure caused by volume changes.

[0072] This application expands the electron collection network from a two-dimensional plane to a three-dimensional network by setting a current-collecting structure extending into the interior of the active material layer. This allows electrons to be captured by the current-collecting structure near the active material layer and directly conducted to the current-collecting plate. The electron transmission distance is reduced from the full thickness of the electrode assembly 30 to the shorter distance from the active material particles to the nearest current-collecting structure, thereby significantly reducing electron transmission impedance and accelerating electron transfer rate. Furthermore, the current-collecting structure and the current-collecting plate are made of the same material, ensuring no contact resistance or electrochemical corrosion risk at the interface, further improving electron conduction efficiency. Simultaneously, the current-collecting structure forms a mechanical interlock with the active material during subsequent pressure molding, enhancing the structural integrity of the thick electrode assembly 30 and solving the process defects of cracking and peeling in thick coatings.

[0073] For details, please continue reading Figure 3 and Figure 4 In some embodiments, the positive current collector 311 includes a positive current collector plate 3111 and a plurality of positive current collector structures 3113 extending from the positive current collector plate 3111 into the positive current collector active material layer 313, wherein the positive current collector plate 3111 and the positive current collector structures 3113 are made of the same material.

[0074] Among them, the positive current collector 3111 is the base part of the positive current collector 311, which is in sheet or foil shape and made of aluminum or aluminum alloy. The positive current collector 3111 is used as the main channel for electron collection and conduction, which evenly distributes the electrons input from the external circuit to the entire electrode area, or collects the electrons generated by the positive active material layer 313 and outputs them to the external circuit.

[0075] The positive current collector structure 3113 is a protruding structure extending from the surface of the positive current collector plate 3111 into the interior of the positive active material layer 313. There are multiple positive current collector structures 3113 (in this text, "multiple" refers to two or more), which are distributed in an array, grid, or irregular pattern on the surface of the positive current collector plate 3111. The positive current collector structure 3113 is one or more of the following: current collector lines, current collector pins, and current collector columns in the positive active material layer 313. That is, the positive current collector structure preform 3113a (described later) Figure 14 (As shown) are one or more of the following: current collector lines, current collector needles, and current collector columns, which are erected on the (unbent) positive electrode current collector plate 3111. Current collector lines refer to slender linear structures with a cross-sectional shape that can be circular, elliptical, or polygonal. Current collector needles are needle-like structures with sharp tips, facilitating insertion into the positive electrode active material 313a during pressurization. Current collector columns are columnar structures with a specific outline, and their cross-sectional shape can be circular, square, or irregular. The positive electrode current collector structure 3113 is made of the same material as the positive electrode current collector plate 3111 to ensure good electronic conductivity and electrochemical stability; it is typically made of aluminum or an aluminum alloy.

[0076] During the preparation of the positive electrode unit 31, the positive electrode active material 313a ( Figure 16 As shown, the positive electrode active material 313a is filled into the gaps between the positive electrode current collector preforms 3113a in the form of dry powder or slurry, and then solidified into a dense positive electrode active material layer 313 by a pressurization process. In one example, during the pressurization process, the positive electrode current collector preforms 3113a (which were originally erected on the surface of the positive electrode current collector plate 3111) Figure 16 As shown, the positive electrode active material 313a undergoes bending deformation under compression, forming a bent positive electrode current collector structure 3113. In another example, after pressurization, the positive electrode current collector structure preform 3113a, which was originally upright on the surface of the positive electrode current collector plate 3111, remains upright, forming a vertically distributed positive electrode current collector structure 3113.

[0077] In this embodiment, the electrode assembly 30 expands the electron collection network from a two-dimensional plane to a three-dimensional network by providing multiple positive current collector structures 3113 extending into the positive active material layer 313 on the positive current collector plate 3111. This allows electrons to be captured by the positive current collector structures 3113 within the positive active material layer 313 and directly conducted to the positive current collector plate 3111. The electron transmission distance is reduced from the full thickness of the electrode assembly 30 to the shorter distance from the active material particle to the nearest positive current collector structure 3113, thereby significantly reducing electron transmission impedance and accelerating electron transfer rate. Furthermore, the positive current collector structures 3113 are made of the same material as the positive current collector plate 3111, ensuring no contact resistance or electrochemical corrosion risk at the interface, further improving electron conduction efficiency. Meanwhile, the positive electrode current collector 3111 forms a mechanical interlock with the positive electrode active material 313a during the subsequent pressure molding process, which enhances the structural integrity of the thick electrode assembly 30 and solves the process defects of thick coating that are prone to cracking and peeling.

[0078] Please continue reading. Figure 3 and Figure 4 In other embodiments, the negative current collector 331 includes a negative current collector plate 3311 and a plurality of negative current collector structures 3313 extending from the negative current collector plate 3311 into the negative current collector active material layer 333, wherein the negative current collector plate 3311 and the negative current collector structures 3313 are made of the same material.

[0079] The negative electrode current collector 3311 is the base part of the negative electrode current collector 331, and is in sheet or foil shape, made of copper or copper alloy. The negative electrode current collector 3311 is used as the main channel for electron collection and conduction, collecting electrons generated by the negative electrode active material layer 333 and outputting them to the external circuit, or uniformly distributing electrons input from the external circuit to the entire electrode area.

[0080] The negative electrode current collector structure 3313 is a protruding structure extending from the surface of the negative electrode current collector plate 3311 into the interior of the negative electrode active material layer 333. There are multiple negative electrode current collector structures 3313, which are distributed in an array, grid, or irregular pattern on the surface of the negative electrode current collector plate 3311. The negative electrode current collector structure 3313 is one or more of the following: current collector lines, current collector pins, and current collector columns in the positive electrode active material layer 313. That is, the negative electrode current collector structure preform 3313a (described later) Figure 22 (As shown) are one or more of the current collector lines, current collector pins, and current collector columns that stand upright on the (unbent) negative electrode current collector plate 3311. The explanations of the current collector lines, current collector pins, and current collector columns are the same as above and will not be repeated here. The negative electrode current collector structure 3313 is made of the same material as the negative electrode current collector plate 3311 to ensure good electronic conductivity and electrochemical stability; it is typically made of copper or a copper alloy.

[0081] During the preparation of negative electrode unit 33, negative electrode active material 333a ( Figure 22 As shown, the negative electrode active material 333a is filled into the gaps between the negative electrode current collector preforms 3313a in the form of dry powder or slurry, and then cured into a dense negative electrode active material layer 333 by a pressurization process. In another example, during the pressurization process, the negative electrode current collector preforms 3313a (which were originally erected on the surface of the negative electrode current collector plate 3311) Figure 22 As shown, the negative electrode active material 333a undergoes bending deformation under compression, forming a bent negative electrode current collector structure 3313. In another example, after pressurization, the negative electrode current collector structure preform 3313a, which was originally upright on the surface of the negative electrode current collector plate 3311, remains upright, forming a vertically distributed negative electrode current collector structure 3313.

[0082] In this embodiment, the electrode assembly 30 expands the electron collection network from a two-dimensional plane to a three-dimensional network by providing multiple negative current collection structures 3313 extending into the interior of the negative electrode active material layer 333 on the negative current collector plate 3311. This allows electrons to be captured by the negative current collector structures 3313 within the negative electrode active material layer 333 and directly conducted to the negative current collector plate 3311. The electron transmission distance is reduced from the full thickness of the electrode assembly 30 to the shorter distance from the active material particle to the nearest negative current collector structure 3313, thereby significantly reducing electron transmission impedance and accelerating electron transfer rate. Furthermore, the negative current collector structures 3313 are made of the same material as the negative current collector plate 3311, ensuring no contact resistance or electrochemical corrosion risk at the interface, further improving electron conduction efficiency. Meanwhile, the negative electrode current collector 3311 forms a mechanical interlock with the negative electrode active material 333a during the subsequent pressure molding process, which enhances the structural integrity of the thick electrode assembly 30 and solves the process defects of thick coating that are prone to cracking and peeling.

[0083] Please see Figure 3 , Figure 4 and Figure 6 As an optional technical solution of this application, the current collection structure is spaced apart from the isolation plate and from the ion conduction column extending into the corresponding active material layer.

[0084] In some embodiments, the positive current collector 3113 is spaced apart from the separator 351 and from the ion conduction pillar 353 extending into the positive active material layer 313. In other embodiments, the negative current collector 3313 is spaced apart from the separator 351 and from the ion conduction pillar 353 extending into the negative active material layer 333.

[0085] This application ensures that the current collector structure contacts the active material in the active material layer only, responsible for collecting and conducting electrons, by separating the current collector structure from the isolation plate and from the ion conduction column. The ion conduction column contacts the electrolyte in the active material layer only, responsible for transporting ions. The two do not interfere with each other, forming a dual-channel cooperative transport network for electrons and ions. Electrons are rapidly conducted to the current collector plate inside the active material layer through the current collector structure, while ions migrate rapidly to the opposite electrode inside the active material layer through the ion conduction column 353. The two are independent yet cooperative, ensuring efficient electron and ion transport and fundamentally avoiding the risk of internal short circuits caused by contact between the current collector structure and the ion conduction column 353.

[0086] Please see Figure 3 and Figure 4 As an optional technical solution in this application, the value range of the flow area S of the current collection structure is 0.00785 mm. 2 ≤S≤3.1416mm 2 This application limits the current-carrying area of ​​the current collector structure to the range of 0.00785 mm² to 3.1416 mm², which ensures that the current collector structure has sufficient current-carrying capacity to support the high-rate charge and discharge requirements of the thick electrode assembly, and also ensures that a good mechanical interlock can be formed between the current collector structure and the active material, while achieving an optimal balance between energy density and electronic conductivity.

[0087] Please see Figure 4 In some embodiments, the current-carrying area S1 of the positive current collector structure 3113 is in the range of 0.00785 mm. 2 ≤S≤3.1416mm 2 .

[0088] The current-carrying area of ​​the positive current collector structure 3113 refers to the cross-sectional area of ​​the positive current collector structure 3113 perpendicular to the electron transport direction. The positive current collector structure 3113 extends from the surface of the positive current collector plate 3111 into the interior of the positive active material layer 313. Electrons enter the positive current collector structure 3113 from various points in the positive active material layer 313 and are conducted to the positive current collector plate 3111 along the axial direction of the positive current collector structure 3113. The size of the current-carrying area S1 directly affects the current-carrying capacity and resistance value of the positive current collector structure 3113: the larger the current-carrying area, the wider the electron transport channel, the lower the resistance value, and the stronger the current-carrying capacity; the smaller the current-carrying area, the narrower the electron transport channel, the higher the resistance value, and the weaker the current-carrying capacity.

[0089] The cross-sectional shape of the positive current collector structure 3113 can be circular, elliptical, or polygonal. When the cross-sectional shape is circular, the relationship between the flow area S1 and the diameter d is S1 = π × d² / 4. The range of the flow area S1 from 0.00785 mm² to 3.1416 mm² corresponds to a diameter d range of 0.1 mm to 2 mm. Specifically, the flow area S1 can be any value among 0.00785 mm², 0.01 mm², 0.02 mm², 0.05 mm², 0.1 mm², 0.2 mm², 0.5 mm², 1.0 mm², 1.5 mm², 2.0 mm², 2.5 mm², and 3.1416 mm², or any value between any two adjacent values.

[0090] When the current-carrying area S1 is less than 0.00785 mm², the cross-sectional area of ​​the positive electrode current collector structure 3113 is too small, and electrons face excessively high current density during transport within the current collector structure. Under high-rate charge and discharge conditions, the large current passing through the small current collector structure easily generates local overheating, leading to increased resistance and energy loss. In severe cases, the current collector structure may melt due to Joule heat accumulation, causing the electrode to lose its electron collection capacity locally, resulting in capacity decay and safety hazards. At the same time, the excessively thin positive electrode current collector structure 3113 lacks sufficient mechanical strength during the pressure molding process, making it prone to excessive bending or even breakage, making it difficult to maintain structural integrity, and also preventing the formation of an effective mechanical interlock with the positive electrode active material 313a.

[0091] When the current-flow area S1 is greater than 3.1416 mm², the cross-sectional area of ​​the positive electrode current collector structure 3113 is too large. On the one hand, the excessively large current collector structure occupies too much internal space of the positive electrode active material layer 313, squeezing the filling volume of the positive electrode active material 313a, resulting in a decrease in the loading of positive electrode active material 313a per unit volume and a decrease in the energy density of the electrode assembly 30. On the other hand, the excessively large positive electrode current collector structure 3113 has excessive rigidity during the pressure molding process, making it difficult to undergo the expected bending deformation. The mechanical interlocking effect between it and the positive electrode active material 313a is weakened, and it cannot effectively suppress the electrical contact failure problem caused by the volume change of the active material during charge and discharge cycles. In addition, the excessively large current-flow area S1 means an increase in the amount of material used in the positive electrode current collector structure 3113, increasing the manufacturing cost.

[0092] In this embodiment, the current-carrying area S1 of the positive current collector structure 3113 is limited to the range of 0.00785 mm² to 3.1416 mm². This ensures that the positive current collector structure 3113 has sufficient current-carrying capacity to support the high-rate charging and discharging requirements of the thick electrode assembly 30, and also ensures that a good mechanical interlock can be formed between the positive current collector structure 3113 and the positive active material 313a. At the same time, it achieves an optimal balance between energy density and electron conductivity.

[0093] Please see Figure 3 In other embodiments, the current-carrying area S2 of the negative electrode current collector structure 3313 is in the range of 0.00785 mm. 2 ≤S≤3.1416mm 2 .

[0094] The current-carrying area S2 of the negative electrode current collector structure 3313 refers to the cross-sectional area of ​​the negative electrode current collector structure 3313 perpendicular to the electron transport direction. The negative electrode current collector structure 3313 extends from the surface of the negative electrode current collector plate 3311 into the interior of the negative electrode active material layer 333. After electrons enter the negative electrode current collector structure 3313 from various points in the negative electrode active material layer 333, they are conducted to the negative electrode current collector plate 3311 along the axial direction of the negative electrode current collector structure 3313. The size of the current-carrying area S2 directly affects the current-carrying capacity and resistance value of the negative electrode current collector structure 3313: the larger the current-carrying area, the wider the electron transport channel, the lower the resistance value, and the stronger the current-carrying capacity; the smaller the current-carrying area, the narrower the electron transport channel, the higher the resistance value, and the weaker the current-carrying capacity.

[0095] The cross-sectional shape of the negative electrode current collector structure 3313 can be circular, elliptical, or polygonal. When the cross-sectional shape is circular, the relationship between the flow area S2 and the diameter d is S2 = π × d² / 4. The range of the flow area S2 from 0.00785 mm² to 3.1416 mm² corresponds to a diameter d range of 0.1 mm to 2 mm. Specifically, the flow area S2 can be any value among 0.00785 mm², 0.01 mm², 0.02 mm², 0.05 mm², 0.1 mm², 0.2 mm², 0.5 mm², 1.0 mm², 1.5 mm², 2.0 mm², 2.5 mm², and 3.1416 mm², or any value between any two adjacent values.

[0096] When the current-carrying area S2 is less than 0.00785 mm², the cross-sectional area of ​​the negative electrode current collector structure 3313 is too small, and electrons face excessively high current density during transport within the current collector structure. Under high-rate charge and discharge conditions, the large current passing through the small current collector structure easily generates local overheating, leading to increased resistance and energy loss. In severe cases, the current collector structure may melt due to Joule heat accumulation, causing the electrode to lose its electron collection capacity locally, resulting in capacity decay and safety hazards. At the same time, the excessively thin negative electrode current collector structure 3313 lacks sufficient mechanical strength during pressure molding, making it prone to excessive bending or even breakage, making it difficult to maintain structural integrity and unable to form an effective mechanical interlock with the negative electrode active material 333a.

[0097] When the current-flow area S2 is greater than 3.1416 mm², the cross-sectional area of ​​the negative electrode current collector structure 3313 is too large. On the one hand, the excessively large negative electrode current collector structure 3313 occupies too much internal space of the negative electrode active material layer 333, crowding out the filling volume of the negative electrode active material 333a, resulting in a decrease in the loading of negative electrode active material 333a per unit volume and a decrease in the energy density of the electrode assembly 30. On the other hand, the excessively large negative electrode current collector structure 3313 has excessive rigidity during the pressurization process, making it difficult to undergo the expected bending deformation. The mechanical interlocking effect between it and the negative electrode active material 333a is weakened, and it cannot effectively suppress the electrical contact failure problem caused by the volume change of the negative electrode active material 333a during charge-discharge cycles. In addition, the excessively large current-flow area S2 means an increase in the amount of material used in the negative electrode current collector structure 3313, increasing the manufacturing cost.

[0098] In this embodiment, the current-carrying area S2 of the negative electrode current collector structure 3313 is limited to the range of 0.00785 mm² to 3.1416 mm². This ensures that the negative electrode current collector structure 3313 has sufficient current-carrying capacity to support the high-rate charging and discharging requirements of the thick electrode assembly 30, and also ensures that a good mechanical interlock can be formed between the negative electrode current collector structure 3313 and the negative electrode active material 333a. At the same time, an optimal balance is achieved between energy density and electron conductivity.

[0099] Please see Figure 5 and Figure 6 As an optional technical solution of this application, the ion conduction column 353 includes a core 3531 and an insulating isolation layer 3533 that completely covers the outer surface of the core 3531. The core 3531 has a porous structure. The insulating isolation layer 3533 is made of the same material as the isolation plate 351.

[0100] The core 3531 is the main body of the ion-conducting column 353, and its overall shape is columnar, extending along the axial direction of the ion-conducting column 353. The length of the core 3531 is the sum of the embedment depth of the ion-conducting column 353 extending from the separator 351 to one side, the embedment depth extending to the other side, and the thickness of the separator 351. The cross-sectional shape of the core 3531 (the cross-section obtained by a plane perpendicular to the axial direction) can be circular, elliptical, or polygonal. The core 3531 has a porous structure, meaning that the core 3531 has an interconnected network of pores inside. The pore size can be from the nanometer to the micrometer scale, and the porosity can be designed according to the ion transport requirements, for example, the porosity range can be 30% to 80%. The function of the porous structure is to form a channel network for ion transport inside the core 3531. When the pores are filled with electrolyte, lithium ions can migrate in the liquid phase within the pore network.

[0101] The insulating layer 3533 completely encapsulates the outer surface of the core 3531, meaning it completely covers the entire outer surface of the core 3531, including its cylindrical surfaces and end faces, forming a complete coating. The thickness of the insulating layer 3533 is in the micrometer range, for example, from 1 micrometer to 10 micrometers, used to form a continuous electronic barrier on the outer surface of the core 3531. The material of the insulating layer 3533 is the same as that of the separator 351, such as a polyolefin porous membrane (e.g., polyethylene, polypropylene), a ceramic-coated membrane, or a cellulose membrane. The insulating layer 3533 can be attached to the outer surface of the core 3531 by impregnation coating, spraying, electrospinning, or thermoforming. Process control ensures that the coating is uniform and free of pinhole defects. Since the insulating layer 3533 is made of the same material as the isolation plate 351, and both have the same insulation performance and ion permeability, a continuous insulating interface can be formed between the insulating layer 3533 and the isolation plate 351 at the position where the ion conduction column 353 passes through the isolation plate 351, thus avoiding weak points in insulation at the connection.

[0102] In the preparation of the ion conduction column 353, a core 3531 with a porous structure can be prepared first, and then a fully encapsulated insulating layer 3533 can be formed on the outer surface of the core 3531. The formation of the insulating layer 3533 can be carried out after the core 3531 is formed, for example, by immersing the core 3531 in a slurry containing a membrane material, and forming a uniform coating layer through multiple immersions and drying; or by using electrospinning to deposit the membrane material on the outer surface of the core 3531.

[0103] After the electrode assembly 30 is assembled, the porous core 3531 of the ion conduction column 353 is filled with electrolyte, forming a three-dimensional interconnected liquid-phase ion transport network. The fully enclosed insulating layer 3533 completely physically isolates the core 3531 from the positive electrode active material layer 313 and the negative electrode active material layer 333, preventing the positive electrode active material 313a and the negative electrode active material 333a from making electronic contact through the core 3531. At the same time, since the insulating layer 3533 and the isolation plate 351 are made of the same material, and the two form a continuous interface at the position where the ion conduction column 353 passes through the isolation plate 351, the entire ion transport unit 35 maintains consistency in insulation performance.

[0104] The electrode assembly 30 of this application uses an ion-conducting column 353 as a core 3531 with a porous structure, and fully encapsulates the outer surface of the core 3531 with an insulating isolation layer 3533 made of the same material as the separator 351. This allows ion conduction to be maintained inside the ion-conducting column 353 while forming a complete electronic barrier on the outer surface of the core 3531. The porous core 3531 has an interconnected pore network inside. After the pores are filled with electrolyte, a three-dimensional interconnected liquid-phase ion transport path is formed, allowing lithium ions to migrate rapidly in the pore network. This reduces the effective ion diffusion distance from the full thickness of the active material layer to the micrometer-level distance between the active material particles and the outer wall of the ion-conducting column 353, thus reducing ion transport impedance. At the same time, the insulating isolation layer 3533 uses the same material as the separator 351, ensuring consistent insulation performance and ion permeability, and avoiding the risk of short circuit between the positive and negative electrode materials that may be caused when the ion-conducting column 353 provides a fast ion channel.

[0105] Please see Figure 7 As an optional technical solution of this application, the ion conduction column 353 is provided with a cavity 3530 closed at both ends, and the material of the periphery of the cavity 3530 is the same as the material of the isolation plate 351.

[0106] The ion conduction column 353 is columnar in shape, extending along its axial direction. Its length is the sum of the embedding depth of the ion conduction column 353 extending from the isolation plate 351 to one side, the embedding depth extending to the other side, and the thickness of the isolation plate 351. The cross-sectional shape of the ion conduction column 353 (explained as above) can be circular, elliptical, or polygonal. The ion conduction column 353 has a closed cavity 3530 inside, which refers to the hollow region located inside the ion conduction column 353. The closed cavity 3530 means that the cavity 3530 is completely separated from the outer surface of the ion conduction column 353 by a peripheral wall, and the interior of the cavity 3530 is not directly connected to the external environment.

[0107] The peripheral wall of cavity 3530 refers to the portion that constitutes the wall of ion conduction column 353, and it also forms the outer wall of ion conduction column 353. The material of the peripheral wall is the same as that of separator 351, such as a polyolefin porous membrane (e.g., polyethylene, polypropylene), ceramic-coated separator, or cellulose separator. Because the peripheral wall uses the same material as separator 351, it has a large number of micropores within its wall thickness range. When the micropores are filled with electrolyte, they form liquid-phase channels for ion conduction. Lithium ions can freely migrate between cavity 3530 and the positive electrode active material layer 313 and negative electrode active material layer 333 outside ion conduction column 353 through the peripheral wall. At the same time, the peripheral wall acts as an insulating material, physically isolating the interior of cavity 3530 from the positive electrode active material layer 313 and negative electrode active material layer 333 outside ion conduction column 353, preventing the positive and negative electrode materials from making electronic contact through cavity 3530.

[0108] In the preparation of the ion conduction column 353, the material of the isolation plate 351 can be directly processed into a columnar structure with a closed cavity 3530 through processes such as injection molding, 3D printing or hot pressing.

[0109] After the electrode assembly 30 is assembled, the enclosed cavity 3530 of the ion conduction column 353 is filled with electrolyte, forming a liquid-phase ion storage region. The porous structure of the periphery of the cavity 3530 allows lithium ions to permeate, enabling ion conduction between the electrolyte inside the cavity 3530 and the electrolytes in the positive electrode active material layer 313 and the negative electrode active material layer 333. During charging and discharging, lithium ions can freely migrate between the cavity 3530 and the active material layer through the micropores of the periphery. The cavity 3530 acts as an additional ion buffer region, helping to balance the ion concentration distribution inside the electrode. Simultaneously, because the periphery uses the same insulating material as the separator 351, the electrolyte inside the cavity 3530 is separated from the active material outside the ion conduction column 353 by the insulating periphery, preventing electronic short circuits.

[0110] The electrode assembly 30 of this application forms a liquid-phase ion channel isolated from the outside inside the ion conduction column 353 by setting a closed cavity 3530 inside the ion conduction column 353 and making the material of the periphery of the cavity 3530 the same as that of the isolation plate 351. The periphery of cavity 3530 is made of the same porous material as the separator 351. The microporous structure of the periphery of cavity 3530, after being filled with electrolyte, forms a liquid-phase ion transport path, allowing lithium ions to migrate freely between cavity 3530 and the active material layer through the periphery. This reduces the effective ion diffusion distance from the full thickness of the active material layer to the micrometer-level distance between the active material particles and the outer wall of the ion conduction column 353, thus reducing ion transport impedance. At the same time, the periphery is made of the same insulating material as the separator 351, physically isolating the electrolyte inside cavity 3530 from the active material outside ion conduction column 353. This prevents the positive and negative electrode active materials from making electronic contact through cavity 3530, avoiding the risk of short circuit between positive and negative electrode materials that may be caused when ion conduction column 353 provides a fast ion channel.

[0111] Please see Figure 8 As an optional technical solution of this application, the ion conduction column 353 includes a core 3531 and an insulating separator 3535. The core 3531 has a cavity or a porous structure. An insulating separator 3535 is provided at the boundary between the positive electrode active material layer 313 and the negative electrode active material layer 333 of the ion conduction column 353. The insulating separator 3535 is made of the same material as the separator 351.

[0112] The core 3531 is the main body of the ion conduction column 353, and its overall shape is columnar, extending along the axial direction of the ion conduction column 353. The length of the core 3531 is the sum of the embedment depth of the ion conduction column 353 extending from the isolation plate 351 to one side and the embedment depth extending to the other side. The cross-sectional shape of the core 3531 (explained as above) can be circular, elliptical, or polygonal. The core 3531 has a cavity, such as... Figure 8 As shown in (a); or, the core 3531 has a porous structure, such as... Figure 8 As shown in (b). Here, the cavity refers to a channel extending axially along the core 3531; the porous structure refers to an interconnected network of pores within the core 3531. The function of the cavity and porous structure is to form channels for ion transport within the core 3531. When the transport channels are filled with electrolyte, lithium ions can migrate in the liquid phase within the transport channels.

[0113] An insulating separator 3535 is disposed at the boundary between the positive electrode active material layer 313 and the negative electrode active material layer 333 of the ion conduction column 353. The boundary refers to the location of the separator 351, i.e., the interface region where the positive electrode active material layer 313 and the negative electrode active material layer 333 are adjacent. The insulating separator 3535 acts as a boundary plate for the core 3531, dividing the core 3531 into upper and lower parts in the height direction Z. The insulating separator 3535 is made of the same material as the separator 351, such as a polyolefin porous membrane (e.g., polyethylene, polypropylene), a ceramic-coated separator, or a cellulose separator. The insulating separator 3535 forms an electron barrier between the positive electrode active material layer 313 and the negative electrode active material layer 333, preventing the positive and negative electrode materials from making electronic contact through the core 3531. Unlike the fully enclosed insulating layer 3533 mentioned above, this solution only sets an insulating insulating sheet 3535 at the boundary. The portion of the core 3531 extending into the positive electrode active material layer 313 and the negative electrode active material layer 333 can remain exposed. The porous structure of these exposed portions can directly contact the active materials. Figure 8 As shown in (b), this facilitates efficient ion exchange between the core 3531 and the active material. In some embodiments, the insulating spacer 3535 is part of the spacer plate 351.

[0114] In the preparation process of ion conduction column 353, firstly, isolation plate 351 is made, and then core 3531 with cavity or porous structure is made on both sides of isolation plate 351.

[0115] After the electrode assembly 30 is assembled, the core 3531 of the ion conduction column 353 is filled with electrolyte to form a liquid-phase ion transport channel. The portion of the core 3531 extending into the positive electrode active material layer 313 is in direct contact with the positive electrode active material layer 313, and the electrolyte in the cavity or porous structure inside the core 3531 is connected to the electrolyte in the positive electrode active material layer 313. Similarly, the portion of the core 3531 extending into the negative electrode active material layer 333 is in direct contact with the negative electrode active material layer 333, and the electrolyte in the cavity or porous structure inside the core 3531 is connected to the electrolyte in the negative electrode active material layer 333. An insulating separator 3535 is located at the boundary, physically isolating the positive electrode active material layer 313 and the negative electrode active material layer 333 to prevent electronic contact between the active materials on both sides through the core 3531.

[0116] The electrode assembly 30 of this application sets the ion conduction column 353 as a core 3531 with a cavity or porous structure, and sets an insulating isolation sheet 3535 of the same material as the isolation plate 351 at the boundary between the ion conduction column 353 and the positive and negative electrode active material layers 333. This allows the core 3531 to maintain ion conduction while forming an electronic barrier at the boundary. After the cavity or porous structure inside the core 3531 is filled with electrolyte, it forms a liquid phase ion transport path. The exposed parts at both ends of the core 3531 are in direct contact with the active material layers on both sides, allowing lithium ions to migrate freely between the core 3531 and the active material layers. This reduces the effective ion diffusion distance from the full thickness of the active material layer to the micrometer-level distance between the active material particles and the outer wall of the ion conduction column 353, thereby reducing the ion transport impedance. The insulating separator 3535 uses the same material as the separator 351. At the boundary, it blocks the positive and negative electrode active materials from making electronic contact through the core 3531, thus avoiding the risk of short circuit between the positive and negative electrode materials that may be caused when the ion conduction column 353 provides a fast ion channel.

[0117] Please see Figure 9 As an optional technical solution of this application, the isolation plate 351 and the ion conduction column 353 are integrally formed.

[0118] The isolation plate 351 and the ion conduction column 353 are integrally molded structures, meaning that the isolation plate 351 and the ion conduction column 353 are manufactured simultaneously through the same molding process, with no obvious dividing line or assembly gap at the interface, forming a continuous and complete integral component. The implementation methods of the integrally molded structure include, but are not limited to, injection molding, 3D printing, thermoforming, or compression molding.

[0119] The electrode assembly 30 of this application integrates the isolation plate 351 and the ion conduction column 353 into a single molded structure, making the ion transport unit 35 a complete component. This integrated structure eliminates assembly errors between the isolation plate 351 and the conduction column, ensuring precise and controllable relative positions of each conduction column and the isolation plate 351. It also reduces assembly steps, solving the problems of short-circuit risks caused by assembly deviations and extremely high requirements for process control precision in traditional split structures, thereby improving production efficiency and yield.

[0120] Please see Figure 10 As an optional technical solution of this application, the electrode assembly 30 has a multi-layer structure, including at least two positive electrode units 31 and at least two negative electrode units 33, with the positive electrode units 31 and negative electrode units 33 stacked alternately, and ion transport units 35 are provided between adjacent units.

[0121] A multilayer structure refers to a composite structure formed by alternating stacking of multiple positive electrode units 31 and multiple negative electrode units 33. In this technical solution, the number of positive electrode units 31 is at least two, and the number of negative electrode units 33 is at least two. The positive electrode units 31 and negative electrode units 33 are arranged alternately according to the pattern of "positive electrode unit 31 - ion transport unit 35 - negative electrode unit 33 - ion transport unit 35 - positive electrode unit 31 - ion transport unit 35 - negative electrode unit 33...". An ion transport unit 35 must be provided between any two adjacent units, that is, an ion transport unit 35 is provided between any positive electrode unit 31 and an adjacent negative electrode unit 33, and between any negative electrode unit 33 and an adjacent positive electrode unit 31.

[0122] The number of layers in the multi-layer structure can be designed according to the capacity and voltage requirements of the battery 100. When a lower capacity is required, fewer layers can be selected, for example, two positive electrode units 31 and two negative electrode units 33 can be alternately stacked to form a four-layer electrode structure, such as... Figure 10 As shown; when higher capacity is required, a larger number of layers can be selected, for example, 10 positive electrode units 31 and 10 negative electrode units 33 can be alternately stacked to form a 20-layer electrode structure, or even more layers. Figure 10 As shown, in an example of a multilayer structure, the outermost electrode unit is a positive electrode unit 31, and the positive current collector 311 of the positive electrode unit 31 can serve as the positive lead-out terminal of the battery 100; the other electrode unit is a negative electrode unit 33, and the negative current collector 331 of the negative electrode unit 33 can serve as the negative lead-out terminal of the battery 100.

[0123] In the assembly of the multilayer structure, multiple positive electrode units 31, multiple negative electrode units 33, and multiple ion transport units 35 are first prepared according to the preparation method described below. These units are then stacked in a predetermined alternating order: first, a positive electrode unit 31 (or negative electrode unit 33) is placed, then an ion transport unit 35 is placed on top of it, then a negative electrode unit 33 (or positive electrode unit 31) is placed on top of the ion transport unit 35, and so on, until the designed number of layers is reached. After stacking, the layers are tightly bonded together by pressure or bonding, ensuring that the two ends of the ion transport pillar 353 are embedded inside the corresponding positive electrode active material layer 313 and negative electrode active material layer 333, respectively.

[0124] Compared to Figure 1 The electrode assembly 30 shown only includes one positive electrode unit 31, one example transmission unit, and one negative electrode unit 33. Figure 10The electrode assembly 30 shown is a multi-layer structure. On the one hand, by increasing the number of layers, the capacity of the battery 100 can be increased without changing the thickness of the electrode unit, meeting the capacity requirements of different application scenarios. On the other hand, multiple positive electrode units 31 and multiple negative electrode units 33 are stacked alternately, which is equivalent to connecting multiple single-layer batteries 100 in series or in parallel, and the voltage can be flexibly configured according to the connection method. Furthermore, the multi-layer structure shares the current collectors at both ends as the total positive and total negative electrodes, reducing the number of external connectors 53 and improving space utilization. Moreover, each layer independently has a fast ion channel provided by the ion conduction column 353 and a three-dimensional electron network provided by the three-dimensional current collector structure, ensuring that each layer can maintain excellent ion and electron transport performance after multi-layer stacking.

[0125] Please see Figure 11 , Figures 14 to 24 Secondly, this application provides a method for preparing an electrode assembly according to any of the above embodiments. The preparation method includes: 01: Provide positive electrode current collector preform 311a and negative electrode current collector preform 331a; 03: The positive electrode active material 313a is combined with the positive electrode current collector preform 311a to form a positive electrode unit 31, which includes a positive electrode current collector 311 and a positive electrode active material layer 313. 05: The negative electrode active material 333a is combined with the negative electrode current collector preform 331a to form a negative electrode unit 33, which includes a negative electrode current collector 331 and a negative electrode active material layer 333. 07: Provide an ion transport unit 35, which includes an isolation plate 351 and a plurality of ion conduction columns 353 protruding from the isolation plate 351 to both sides; 09: The ion transport unit 35 is disposed between the positive electrode unit 31 and the negative electrode unit 33, and the two ends of the ion conduction column 353 are respectively embedded inside the positive electrode active material layer 313 and the negative electrode active material layer 333, thereby obtaining the electrode assembly 30. The ion conduction column 353 is configured to have a transport channel for ion transport and to prevent the positive active material 313a in the positive active material layer 313 and the negative active material 333a in the negative active material layer 333 from making electronic contact through the ion conduction column 353.

[0126] The positive current collector preform 311a is a semi-finished positive current collector 311 that has not yet been bonded to the positive current collector material 313a. It includes a positive current collector plate 3111 and multiple positive current collector structure preforms 3113a extending to one side from the positive current collector plate 3111. The positive current collector structure preform 3113a is the prototype of the positive current collector structure 3113. It can bend and deform during subsequent pressurization, or it can remain upright, eventually forming a three-dimensional current collector structure embedded inside the positive current collector material layer 313. The negative current collector preform 331a has a similar structure to the positive current collector preform 311a, including a negative current collector plate 3311 and multiple negative current collector preforms extending to one side from the negative current collector plate 3311. Its material is copper or copper alloy.

[0127] The step of combining the positive electrode active material 313a with the positive electrode current collector preform 311a to form the positive electrode unit 31 can be achieved using a filling and pressurizing process. For details, please refer to [link to relevant documentation]. Figure 12 , Figures 14 to 20 03: The positive electrode active material 313a is combined with the positive electrode current collector preform 311a to form a positive electrode unit 31, including: 031: Place the positive electrode current collector preform 311a into the processing tank 40; 033: Add positive electrode active material 313a to the processing tank 40, and fill the positive electrode active material 313a between the positive electrode current collector structure preforms 3113a of the positive electrode current collector preform 311a; and 035: Pressurize the filled structure to cause the positive electrode current collector preform 3113a to bend or remain upright, to solidify the positive electrode active material 313a into a positive electrode active material layer 313, and to form at least two first mounting channels 3130 in the positive electrode active material layer 313 to form a positive electrode unit 31.

[0128] Please see Figure 14 and Figure 15In step 031, the positive electrode current collector preform 311a includes a positive electrode current collector plate 3111 and multiple positive electrode current collector structure preforms 3113a extending from the surface of the positive electrode current collector plate 3111. The explanation of the positive electrode current collector plate 3111 is the same as before. The positive electrode current collector structure preform 3113a is a protruding structure extending vertically from the surface of the positive electrode current collector plate 3111, and its shape can be one or more of current collector lines, current collector needles, current collector columns, current collector fibers, or current collector nets. When the positive electrode current collector preform 311a is placed in the processing tank 40, the positive electrode current collector plate 3111 is located at the bottom of the processing tank 40, the positive electrode current collector structure preform 3113a is upright, and gaps are formed between each positive electrode current collector structure preform 3113a to accommodate the positive electrode active material 313a. The shape and size of the processing groove 40 are matched with the positive electrode current collector 3111. The side wall of the processing groove 40 plays a limiting role in the subsequent pressurization process, ensuring that the external dimensions of the positive electrode active material layer 313 meet the design requirements.

[0129] Please see Figure 16 and Figure 17 In step 033, the positive electrode active material 313a is added to the processing tank 40 in the form of dry powder or slurry. Dry powder refers to a dry powder formed by mixing positive electrode active material 313a powder with a conductive agent and binder in a specific ratio; no solvent is needed, and it can be cured and formed by subsequent pressure after addition. Slurry refers to a suspension formed by dispersing positive electrode active material 313a powder with a conductive agent and binder in a solvent; after addition, it needs to be dried to remove the solvent before being cured and formed by pressure. After the positive electrode active material 313a is added, it is uniformly filled into the gaps between the positive electrode current collector preforms 3113a by means of vibration, leveling, or light pressure, and covers the top of the positive electrode current collector preforms 3113a, so that the positive electrode active material layer 313 completely encapsulates the positive electrode current collector preforms 3113a in the height direction Z.

[0130] Please see Figure 18 and Figure 19 In step 035, the filled structure is pressurized. The pressurization method can be as follows: Figure 18The pressurizing device 50 shown applies pressure. The pressurizing device 50 includes a pressure head 51 and a connector 53. The pressure head 51 includes a pressure head body 511 and a plurality of columns 513 extending from the pressure head body 511. One side of the connector 53 is connected to the side of the pressure head body 511 away from the columns 513, and the other side is connected to an external drive device (not shown). Driven by the external drive device, the connector 53 moves the pressure head 51 up and down in the height direction Z to pressurize the positive electrode active material 313a and the positive electrode current collector preform 311a in the processing tank 40. As the pressurizing device 50 descends to approach the positive electrode active material 313a within the processing tank 40, the column 513 descends along with the pressure head body 511 and gradually inserts into the positive electrode active material 313a. As the pressure head body 511 continues to descend, it transmits pressure through the positive electrode active material 313a to the positive electrode current collector preform 3113a. In one example, the pressure can cause the originally upright positive electrode current collector preform 3113a to bend and deform due to the compression of the positive electrode active material 313a. The specific shape of the bending deformation depends on the original shape of the positive electrode current collector preform 3113a, its material properties, and the pressurizing parameters, and can manifest as an S-shape, C-shape, wavy shape, or irregular bend. This bending deformation significantly increases the contact area between the positive electrode current collector 3113 and the positive electrode active material 313a, forming a mechanical interlocking structure similar to that between steel bars and concrete in concrete. In another example, pressure can compact the positive electrode active material 313a, but it will not bend the originally upright positive electrode current collector preform 3113a. Instead, it will remain upright, and the diameter of the positive electrode current collector preform 3113a will be larger in this case.

[0131] While pressurizing, the positive electrode active material 313a is compressed and compacted under pressure, with particles interlocking. The binder (such as an adhesive) flows and solidifies under pressure, causing the positive electrode active material 313a to solidify into a dense positive electrode active material layer 313. The pillars 513 form the first mounting channels 3130 within the positive electrode active material layer 313. The number of first mounting channels 3130 corresponds to the number of ion conduction pillars 353 on one side of the separator 351, and the distribution of the first mounting channels 3130 corresponds to the position of the ion conduction pillars 353 on one side of the separator 351. The first mounting channels 3130 form a guiding structure within the positive electrode active material layer 313, providing a positioning reference for the subsequent precise embedding of the ion conduction pillars 353.

[0132] Please see Figure 20 and Figure 21After the positive electrode unit 31 is fabricated, the positive electrode current collector 3111, as the main channel for electron collection and conduction, is located on the outermost side of the positive electrode unit 31. In the illustrated embodiment, the positive electrode current collector structure 3113 is curved in the positive electrode active material layer 313 to form a three-dimensional electron network. The positive electrode active material layer 313 has a dense structure. The first mounting channel 3130 is distributed in the positive electrode active material layer 313, and the position of the first mounting channel 3130 corresponds precisely to the distribution position of the ion conduction column 353 on one side of the separator 351.

[0133] The method for preparing the positive electrode unit 31 in this application simultaneously achieves the construction of the positive electrode electron network, the forming of the positive electrode unit 31, and the prefabrication of the first mounting channel 3130 by applying pressure once. This not only solves the problems of easy cracking, difficult drying, and difficulty in ensuring density uniformity in traditional processes, but also provides the first mounting channel 3130 for guiding the precise embedding of the ion conduction column 353 into the positive electrode active material 313a.

[0134] The step of combining the negative electrode active material 333a with the negative electrode current collector preform 331a to form the negative electrode unit 33 can also be achieved using a filling and pressurizing process. For details, please refer to [link to relevant documentation]. Figure 13 , Figure 22 and Figure 23 05: The negative electrode active material 333a is combined with the negative electrode current collector preform 331a to form a negative electrode unit 33, including: 051: Place the negative electrode current collector preform 331a into the processing tank 40; 053: Add negative electrode active material 333a to the processing tank 40, and fill the negative electrode active material 333a between the negative electrode current collector structure preforms 3313a of the negative electrode current collector preform 331a; and 055: Pressurize the filled structure to cause the negative electrode current collector preform 3313a to bend or remain upright, to solidify the negative electrode active material 333a into a negative electrode active material layer 333, and to form at least two second mounting channels 3330 in the negative electrode active material layer 333 to form a negative electrode unit 33.

[0135] Please see Figure 13 , Figure 22 and Figure 23In step 051, the negative electrode current collector preform 331a includes a negative electrode current collector plate 3311 and multiple negative electrode current collector structure preforms 3313a extending from the surface of the negative electrode current collector plate 3311. The negative electrode current collector plate 3311 is explained as before. The negative electrode current collector structure preform 3313a is a protruding structure extending vertically from the surface of the negative electrode current collector plate 3311, and its shape can be one or more of current collector lines, current collector needles, current collector columns, current collector fibers, or current collector nets. When the negative electrode current collector preform 331a is placed in the processing tank 40, the negative electrode current collector plate 3311 is located at the bottom of the processing tank 40, the negative electrode current collector structure preform 3313a is upright, and gaps are formed between each negative electrode current collector structure preform 3313a to accommodate the negative electrode active material 333a. The shape and size of the processing groove 40 are matched with the negative electrode current collector 3311. The side wall of the processing groove 40 plays a limiting role in the subsequent pressurization process, ensuring that the external dimensions of the negative electrode active material layer 333 meet the design requirements.

[0136] Please see Figure 22 In step 053, the negative electrode active material 333a is added to the processing tank 40 in the form of dry powder or slurry. Dry powder refers to a dry powder formed by mixing negative electrode active material 333a powder with a conductive agent and binder in a specific ratio; no solvent is needed, and it can be cured and formed by subsequent pressure after addition. Slurry refers to a suspension formed by dispersing negative electrode active material 333a powder with a conductive agent and binder in a solvent; after addition, it needs to be dried to remove the solvent before being cured and formed by pressure. After the negative electrode active material 333a is added, it is uniformly filled into the gaps between the negative electrode current collector preforms 3313a by means of vibration, leveling, or light pressure, and covers the top of the negative electrode current collector preforms 3313a, so that the negative electrode active material layer 333 completely encapsulates the negative electrode current collector preforms 3313a in the height direction Z.

[0137] Please see Figure 22In step 055, the filled structure is pressurized. The pressurization can be performed using a pressurizing device 50, as explained above. The connecting piece 53, driven by an external drive device, moves the pressure head 51 up and down in the height direction Z to pressurize the negative electrode active material 333a and the negative electrode current collector preform 331a in the processing tank 40. As the pressurizing device 50 descends to approach the negative electrode active material 333a in the processing tank 40, the column 513 descends along with the pressure head body 511 and gradually inserts into the negative electrode active material 333a. As the pressure head body 511 continues to descend, it transmits pressure through the negative electrode active material 333a to the negative electrode current collector preform 3313a. In one example, the pressure can cause the originally upright negative electrode current collector preform 3313a to bend and deform due to the compression of the negative electrode active material 333a. The specific form of the bending deformation depends on the original shape, material properties, and pressure parameters of the negative electrode current collector prefabricated component 3313a, and can manifest as an S-shape, C-shape, wavy shape, or irregular bending shape. This bending deformation significantly increases the contact area between the negative electrode current collector structure 3313a and the negative electrode active material 333a, forming a mechanical interlocking structure similar to that between steel bars and concrete in concrete. In another example, pressure can compact the negative electrode active material 333a, but it will not cause the originally upright negative electrode current collector prefabricated component 3313a to bend; instead, it will remain upright, in which case the diameter of the negative electrode current collector prefabricated component 3313a is larger.

[0138] While pressurizing, the negative electrode active material 333a is compressed and compacted under pressure, with particles interlocking. The binder (such as an adhesive) flows and solidifies under pressure, causing the negative electrode active material 333a to solidify into a dense negative electrode active material layer 333. The column 513 forms a second mounting channel 3330 within the negative electrode active material layer 333. The number of second mounting channels 3330 corresponds to the number of ion conduction columns 353 on the other side of the separator 351, and the distribution position of the second mounting channels 3330 corresponds to the position of the ion conduction columns 353 on the other side of the separator 351. The second mounting channels 3330 form a guiding structure within the negative electrode active material layer 333, providing a positioning reference for the precise embedding of the subsequent ion conduction columns 353.

[0139] Please see Figure 23 and Figure 24After the negative electrode unit 33 is fabricated, the negative electrode current collector 3311, as the main channel for electron collection and conduction, is located on the outermost side of the negative electrode unit 33. In the illustrated embodiment, the negative electrode current collector structure 3313 is curved in the negative electrode active material layer 333 to form a three-dimensional electron network. The negative electrode active material layer 333 has a dense structure. The second mounting channel 3330 is distributed in the negative electrode active material layer 333, and the position of the second mounting channel 3330 corresponds precisely to the distribution position of the ion conduction column 353 on the other side of the isolation plate 351.

[0140] The preparation method of this application simultaneously achieves the construction of the three-dimensional electron network of the negative electrode, the molding of the negative electrode unit 33, and the prefabrication of the second mounting channel 3330 by applying pressure once. This not only solves the problems of easy cracking, difficult drying, and difficulty in ensuring density uniformity in traditional processes, but also provides a second mounting channel 3330 for guiding the precise embedding of the ion conduction column 353 into the negative electrode active material 333a.

[0141] Please see Figure 2 The step of placing the ion transport unit 35 between the positive electrode unit 31 and the negative electrode unit 33, and embedding the two ends of the ion conduction column 353 into the positive electrode active material layer 313 and the negative electrode active material layer 333 respectively, is the key process for assembling the above units into a complete electrode assembly 30.

[0142] Specifically, the positive electrode unit 31, the ion transport unit 35, and the negative electrode unit 33 are stacked in sequence, with one end of the ion conduction column 353 aligned with the first mounting channel 3130 of the positive electrode unit 31, and the other end aligned with the second mounting channel 3330 of the negative electrode unit 33. Pressure is then applied to press both ends of the ion conduction column 353 into the first mounting channel 3130 and the second mounting channel 3330, respectively, until the separator 351 is in close contact with the positive electrode active material layer 313 and the negative electrode active material layer 333. During the pressing process, the ends of the ion conduction column 353 may further embed into the active material layer; specifically, both ends of the ion conduction column 353 are respectively embedded into the first mounting channel 3130 and the second mounting channel 3330, ensuring good ion contact between the ion conduction column 353 and the active material layer. Meanwhile, the insulating structure of the ion conduction column 353 (insulating isolation layer 3533 or insulating isolation sheet 3535) ensures that the positive electrode active material 313a and the negative electrode active material 333a will not make electronic contact through the ion conduction column 353.

[0143] The preparation method of this application involves placing the ion transport unit 35 between the positive electrode unit 31 and the negative electrode unit 33, and embedding the two ends of the ion conduction column 353 into the first mounting channel 3130 and the second mounting channel 3330 respectively. This achieves precise alignment and assembly of the ion conduction column 353 with the positive and negative electrode active material layers 333, avoiding short circuits or ion channel failures caused by assembly deviations during the embedding process of the ion conduction column 353, and improving assembly accuracy and product yield.

[0144] It should be noted that the order of the steps in the above preparation method can be adjusted according to the actual situation. For example, the positive electrode unit 31 and the negative electrode unit 33 can be prepared first, followed by the ion transport unit 35, and finally assembled; alternatively, the ion transport unit 35 can be prepared first, followed by the positive electrode unit 31 and the negative electrode unit 33. The preparation of the positive electrode unit 31 and the negative electrode unit 33 can be carried out simultaneously or sequentially. The embedding of the ion conduction column 353 into the positive and negative electrode active material layers 333 can be performed after the positive electrode unit 31 and the negative electrode unit 33 have been prepared, or it can be performed before the positive electrode unit 31 or the negative electrode unit 33 has been completely cured, in order to enhance the embedding effect.

[0145] The preparation method of this application combines positive electrode active material 313a with positive electrode current collector preform 311a to form positive electrode unit 31, and combines negative electrode active material 333a with negative electrode current collector preform 331a to form negative electrode unit 33. Then, an ion transport unit 35 is disposed between the positive and negative electrode units 33, and the two ends of the ion conduction column 353 are respectively embedded inside the positive and negative electrode active material layers 333, thereby realizing the integrated molding of the electrode assembly 30. This method uses filling and pressurizing processes to replace the traditional multiple processes of stirring, coating, drying, rolling, and slitting, solving the problems of long process flow, large equipment investment, high production cost, and low yield in traditional electrode manufacturing processes. It greatly simplifies the process, reduces energy consumption, and improves production efficiency.

[0146] Please see Figure 25 Thirdly, this application provides a battery 100. The battery 100 includes the electrode assembly 30 of any of the above embodiments. More specifically, the battery 100 includes a housing 10, the electrode assembly 30 housed within the housing 10, and an electrolyte housed within the housing 10.

[0147] Battery 100 is a rechargeable electrochemical energy storage device. Battery 100 can be, but is not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries. Optionally, battery 100 can be a secondary battery, meaning a battery 100 that can be recharged after discharge to activate its active materials and continue to be used. Battery 100 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application does not specifically limit its use.

[0148] The casing 10 is a container that forms the internal environment of the battery 100, used to house the electrode assembly 30, electrolyte, and other functional components. The casing 10 can be made of metallic materials such as aluminum, aluminum alloy, or stainless steel, or of polymeric materials such as polypropylene or polyethylene, or a composite structure of metal and polymeric materials such as aluminum-plastic film. The shape of the casing 10 can be square, cylindrical, or other shapes suitable for housing the battery cell, specifically determined according to the shape of the electrode assembly 30 and application requirements. The casing 10 is equipped with an explosion-proof valve 15 and electrode terminals. The explosion-proof valve 15 is used to rupture and release pressure when the internal pressure of the battery 100 exceeds a safety threshold, and the electrode terminals are used to connect to an external circuit. Specifically, the casing 10 includes a casing body 11 and a top cover 13. The casing body 11 is typically an open container at one end, and the top cover 13 is used to close the open end of the casing body 11.

[0149] The electrolyte is an ion-conducting medium filled within the housing 10 to wet the electrode assembly 30, and is typically composed of lithium salts, organic solvents, and additives. During normal charging and discharging, lithium ions move back and forth between the positive and negative electrodes via the electrolyte, inserting and de-inserting.

[0150] Please combine Figure 2 and Figure 3 In the battery 100 of this application, the electrode assembly 30 constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly 30 by setting ion conduction pillars 353 extending to both sides and embedded within the positive and negative electrode active material layers 333 on the separator 351. The ion conduction pillars 353 are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers 333 to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar 353, thereby reducing ion transport impedance and solving the problem of increased internal resistance in the thick electrode assembly 30. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly 30 is more uniform, avoiding lithium plating caused by localized lithium deficiency. This ensures that the battery 100 with the thick electrode assembly 30 possesses good rate performance and cycle life.

[0151] Please see Figures 26 to 28Fourthly, this application provides an energy storage device. The energy storage device includes a housing 200 and a battery 100 according to any of the above embodiments, the battery 100 being housed in the housing 200.

[0152] In some implementations, please refer to Figure 26 The energy storage device is a battery pack 100A. The battery pack 100A includes a housing 200 and a battery 100 according to any of the above embodiments, with the battery 100 housed in the housing 200.

[0153] Battery 100 is the smallest unit for storing and releasing electrical energy. Battery pack 100A can store and release energy by connecting and controlling batteries 100. Multiple batteries 100 can be connected in series, parallel, or in a hybrid configuration, where multiple batteries 100 are connected in both series and parallel configurations. Multiple batteries 100 can be directly connected in series, parallel, or in a hybrid configuration, and then the entire assembly of multiple batteries 100 is housed within a carrier (e.g., casing 200). Battery pack 100A may also include other structures; for example, battery pack 100A may also include a busbar (not shown) for electrical connection between multiple batteries 100. It is understood that the number of batteries 100 in battery pack 100A can be adaptively adjusted according to the application scenario and capacity.

[0154] The outer casing 200 is a structure for housing the battery 100. The cross-section of the outer casing 200 may be, but is not limited to, circular, elliptical, square, or other polygonal shapes. The material of the outer casing 200 includes, but is not limited to, metal or non-metal, wherein metals include aluminum, iron, steel, aluminum alloys, or iron alloys, and non-metals include, but are not limited to, plastics. In this application, the cross-section of the outer casing 200 is rectangular. The material of the outer casing 200 is aluminum alloy, thus, while ensuring strength, it also makes the battery pack 100A lighter and easier to transport.

[0155] The outer casing 200 includes a housing 201 and a cover 203. The housing 201 and the cover 203 are combined to form a receiving cavity, in which the battery 100 is housed. The housing 201 is the component in the outer casing 200 that loads and supports the battery 100. One end of the housing 201 is closed, and the other end has an opening for the battery 100 to be inserted into the receiving cavity. The cover 203 is the component in the outer casing 200 that covers the opening. The connection between the housing 201 and the cover 203 can be detachable or non-detachable. Detachable connections include, but are not limited to, screw connections, snap-fit ​​connections, or a combination of screw connections and snap-fit ​​connections. Non-detachable connections include, but are not limited to, glued connections, welded connections, or a combination of glued connections and welded connections. In this application, the housing 201 and the cover 203 are detachably connected.

[0156] When the outer casing 200 includes a housing 201 and a cover 203, the outer casing 200 may not be made of a single material. For example, the housing 201 and the cover 203 may be made of the same material, aluminum alloy. The outer casing 200 may also have different components made of different materials. For example, the housing 201 may be made of metal, while the cover 203 may be made of plastic. Of course, the materials of the housing 201 and the cover 203 can also be combinations of other different materials, which will not be listed here.

[0157] Please combine Figure 2 and Figure 3 In the battery pack 100A of this application, the electrode assembly 30 constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly 30 by setting ion conduction pillars 353 extending to both sides and embedded within the positive and negative electrode active material layers 333 on the separator 351. The ion conduction pillars 353 are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers 333 to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar 353, thereby reducing ion transport impedance and solving the problem of increased internal resistance in the thick electrode assembly 30. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly 30 is more uniform, avoiding lithium plating caused by localized lithium deficiency. This ensures that the battery 100 with the thick electrode assembly 30 possesses good rate performance and cycle life.

[0158] In other implementations, please refer to Figure 27 The energy storage device is an energy storage system 1000. The energy storage system 1000 includes a battery cabinet 300A and a battery pack 100A according to any of the above embodiments, and the battery pack 100A is housed in the battery cabinet 300A.

[0159] The energy storage system 1000, as a large-scale electrochemical energy storage device, is an energy storage unit composed of multiple battery packs 100A. These battery packs 100A are centrally arranged and installed within a battery cabinet 300A. The battery cabinet 300A provides system-level functions such as physical support, electrical busbars, thermal management interfaces, and safety protection.

[0160] Please combine Figure 2 and Figure 3In the energy storage system 1000 of this application, the electrode assembly 30 constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly 30 by setting ion conduction pillars 353 extending to both sides and embedded within the positive and negative electrode active material layers 333 on the separator 351. The ion conduction pillars 353 are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers 333 to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar 353, thereby reducing ion transport impedance and solving the problem of increased internal resistance in the thick electrode assembly 30. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly 30 is more uniform, avoiding lithium plating caused by localized lithium deficiency, thus ensuring that the battery 100 with the thick electrode assembly 30 has good rate performance and cycle life.

[0161] In some other implementations, please refer to Figure 28 The energy storage device is the electrical equipment 10000. The electrical equipment 10000 includes a high-voltage cable 2000, a first power conversion device 3000, a second power conversion device 4000, and an energy storage system 1000 according to any embodiment provided in this application. In some embodiments of the power generation scenario, the second power conversion device 4000 can be a wind power conversion device. Since the electricity generated by wind power conversion is volatile, random, and intermittent, the unstable electricity output by the wind power conversion device can be stored in the energy storage system 1000 through grid connection. The energy storage system 1000 is connected to the high-voltage cable and outputs smooth electricity to the power consumption side of the distribution network, achieving peak shaving and frequency regulation, and stable grid operation; or, the wind power conversion... The device is always connected to the high-voltage cable. Under normal power generation conditions, the power output of the wind power conversion device is supplied to the power consumption side of the distribution network through the high-voltage cable. When the current power load is low and the wind power conversion device generates excess power, the excess power is first stored in the energy storage system 1000 to reduce wind and solar curtailment rates and improve the problem of new energy power generation consumption. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage system 1000 together with the high-voltage cable 2000 in grid-connected mode to supply power to the power consumption side. This provides the power grid with various services such as peak shaving, frequency regulation, and backup, giving full play to the peak shaving role of the power grid, promoting peak shaving and valley filling, and alleviating the power supply pressure of the power grid.

[0162] In some embodiments on the distribution network side, the first power conversion device 3000 can be a photovoltaic power conversion device. The energy storage system 1000 is connected to the high-voltage cable 2000 and installed downstream of the high-voltage cable 2000 and between the user load. The power output by the photovoltaic power conversion device is stored in the energy storage system 1000, which can respond in a timely manner and act as a backup power source when the power grid / distribution network fails. Alternatively, it can provide power supply support to alleviate line congestion when the high-voltage cable 2000 transmission line is blocked, and to delay the economic pressure caused by the expansion of the power grid / distribution capacity when the power grid is planned to be expanded.

[0163] Optionally, the first power conversion device 3000 may include, but is not limited to, a wind power conversion device, and the second power conversion device 4000 may include, but is not limited to, a photovoltaic power conversion device. The first power conversion device 3000 and the second power conversion device 4000 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy.

[0164] Please combine Figure 2 and Figure 3 In the electrical device 10000 of this application, the electrode assembly 30 constructs a penetrating liquid-phase ion transport channel within the thick electrode assembly 30 by setting ion conduction pillars 353 extending to both sides and embedded in the positive and negative electrode active material layers 333 on the separator 351. The ion conduction pillars 353 are filled with electrolyte, allowing lithium ions to migrate rapidly through the liquid phase. This reduces the effective diffusion distance from the full thickness of the positive and negative electrode active material layers 333 to a shorter distance between the positive / negative electrode active material particles and the nearest ion conduction pillar 353, thereby reducing ion transport impedance and solving the problem of increased internal resistance in the thick electrode assembly 30. Simultaneously, because the ion supply can promptly meet the reaction requirements, the current distribution within the electrode assembly 30 is more uniform, avoiding lithium plating caused by localized lithium deficiency, thus ensuring that the battery 100 with the thick electrode assembly 30 has good rate performance and cycle life.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An electrode assembly, characterized in that, include: The positive electrode unit includes a positive electrode current collector and a positive electrode active material layer; The negative electrode unit comprises a negative electrode current collector and a negative electrode active material layer; and, An ion transport unit disposed between the positive electrode unit and the negative electrode unit, the ion transport unit comprising: A separator plate is located between the positive electrode active material layer and the negative electrode active material layer to physically isolate the positive electrode unit and the negative electrode unit; and At least two ion-conducting pillars extend from the separator to both sides and are respectively embedded inside the positive electrode active material layer and the negative electrode active material layer. The ion-conducting pillars are configured to have a transmission channel for ion transport and to prevent the positive electrode active material in the positive electrode active material layer and the negative electrode active material in the negative electrode active material layer from making electronic contact through the ion-conducting pillars.

2. The electrode assembly according to claim 1, characterized in that, The thickness T1 of the positive electrode unit satisfies: 0.5mm≤T1≤15mm; and / or, the thickness T2 of the negative electrode unit satisfies: 0.5mm≤T2≤15mm.

3. The electrode assembly according to claim 1, characterized in that, At least one of the positive current collector and the negative current collector includes: manifold; and Multiple current collection structures extend from the current collector plate into the corresponding active material layer, and the current collection structures are made of the same material as the current collector plate.

4. The electrode assembly according to claim 3, characterized in that, In the height direction from the positive electrode unit to the negative electrode unit, the current collection structure is spaced apart from the separator plate and from the ion conduction column extending into the corresponding active material layer.

5. The electrode assembly according to claim 3, characterized in that, The flow area S of the current collection structure is in the range of 0.00785 mm. 2 ≤S≤3.1416mm 2 .

6. The electrode assembly according to claim 3, characterized in that, The current collector structure is vertical within the active material layer. The current collector structure includes a positive current collector structure and a negative current collector structure. The active material layer includes a positive active material layer and a negative active material layer. The length of the positive current collector structure is less than or equal to the thickness of the positive active material layer, and the length of the negative current collector structure is less than or equal to the thickness of the negative active material layer; or... The current collection structure is curved within the active material layer.

7. The electrode assembly according to any one of claims 1-6, characterized in that, The ion-conducting column comprises: A core and an insulating layer completely enclosing the outer surface of the core; the core has a porous structure, and the insulating layer is made of the same material as the isolation plate; or, The ion conduction column has a cavity with closed ends inside, and the material of the peripheral wall of the cavity is the same as that of the isolation plate.

8. The electrode assembly according to any one of claims 1-6, characterized in that, The ion-conducting column comprises: The core has a cavity or a porous structure; and An insulating separator is provided at the boundary between the positive electrode active material layer and the negative electrode active material layer of the ion conduction column, and the insulating separator is made of the same material as the separator plate.

9. The electrode assembly according to claim 1, characterized in that, The electrode assembly has a multilayer structure, including at least two positive electrode units and at least two negative electrode units, with the positive electrode units and negative electrode units stacked alternately, and the ion transport units are disposed between adjacent units.

10. A preparation method for preparing the electrode assembly according to any one of claims 1 to 9, characterized in that, The preparation method includes: We provide positive electrode current collector preforms and negative electrode current collector preforms; The positive electrode active material is combined with the positive electrode current collector preform to form a positive electrode unit, the positive electrode unit comprising a positive electrode current collector and a positive electrode active material layer; The negative electrode active material is combined with the negative electrode current collector preform to form a negative electrode unit, the negative electrode unit comprising a negative electrode current collector and a negative electrode active material layer; An ion transport unit is provided, the ion transport unit including an isolation plate and a plurality of ion conduction columns protruding from the isolation plate to both sides; The ion transport unit is disposed between the positive electrode unit and the negative electrode unit, and the two ends of the ion conduction column are respectively embedded inside the positive electrode active material layer and the negative electrode active material layer to obtain the electrode assembly. The ion-conducting column is configured to have a transmission channel for ion transport and to prevent the positive active material in the positive electrode active material layer from making electronic contact with the negative active material in the negative electrode active material layer through the ion-conducting column.

11. The preparation method according to claim 10, characterized in that, The positive current collector includes a positive current collector plate and at least two positive current collector structure preforms extending from the positive current collector plate; the step of combining the positive active material with the positive current collector preforms to form a positive electrode unit includes: The positive electrode current collector preform is placed into the processing tank; A positive electrode active material is added to the processing tank, and the positive electrode active material is filled between the positive electrode current collector structure preforms of the positive electrode current collector preform; and Pressurize the filled structure to cause the positive electrode current collector preform to bend or remain upright, to solidify the positive electrode active material into the positive electrode active material layer, and to form at least two first mounting channels in the positive electrode active material layer to form the positive electrode unit.

12. The preparation method according to claim 11, characterized in that, The negative electrode current collector includes a negative electrode current collector plate and at least two negative electrode current collector preforms extending from the negative electrode current collector plate; the step of combining the negative electrode active material with the negative electrode current collector preforms to form a negative electrode unit includes: Place the negative electrode current collector preform into the processing tank; A negative electrode active material is added to the processing tank, and the negative electrode active material is filled between the negative electrode current collector structure preforms of the negative electrode current collector preform; and Pressurize the filled structure to cause the negative electrode current collector preform to bend or remain upright, to solidify the negative electrode active material into the negative electrode active material layer, and to form at least two second mounting channels in the negative electrode active material layer to form the negative electrode unit.

13. The preparation method according to claim 12, characterized in that, The step of disposing the ion transport unit between the positive electrode unit and the negative electrode unit, and embedding both ends of the ion conduction post into the positive electrode active material layer and the negative electrode active material layer, respectively, includes: The ion transport unit is disposed between the positive electrode unit and the negative electrode unit, and the two ends of the ion conduction column are respectively embedded inside the first mounting channel and the second mounting channel.

14. A battery, characterized in that, It includes at least one electrode assembly as described in any one of claims 1 to 9.

15. An energy storage device, characterized in that, include: shell; and The battery of claim 14, wherein the battery is housed in the housing.

Images