Electrode for lithium-ion battery and method for manufacturing the same

Abstract

An electrode for a lithium ion battery includes a current collector, a binder particle group, and an active material layer. The binder particle group is attached to a surface of the current collector. The active material layer is disposed on the surface of the current collector. The active material layer includes an active material particle group. The binder particle group is interspersed at an interface between the active material layer and the current collector. The electrode for a lithium ion battery of the present disclosure can reduce an increase in interface resistance.

Description

Technical Field

[0001] This disclosure relates to electrodes for lithium-ion batteries and methods for manufacturing the same. Background Technology

[0002] Japanese Patent Application Publication No. 2016-122631 discloses the formation of an adhesive coating on a current collector. Summary of the Invention

[0003] Electrodes for lithium-ion batteries (hereinafter sometimes simply referred to as "electrodes") are manufactured by forming an active material layer on the surface of a current collector foil. To improve the peel strength between the active material layer and the current collector foil, it is considered to form an adhesive film between the active material layer and the current collector foil.

[0004] Traditionally, adhesive films are formed using a wet process. That is, an adhesive film is formed by applying an adhesive solution to the surface of the current collector foil. The adhesive film covers the surface of the current collector foil. The adhesive is a resistive component. Because the adhesive film lies between the current collector foil and the active material layer, the interfacial resistance (electronic resistance) between the current collector foil and the active material layer may increase.

[0005] This disclosure reduces the increase in interface resistance.

[0006] The technical solution and effects of this disclosure are described below. However, the mechanism of action in this specification includes conjecture. The mechanism of action does not limit the technical scope of this disclosure.

[0007] The electrode for a lithium-ion battery according to the first aspect of this disclosure includes a current collector foil, a group of binder particles, and an active material layer. The binder particles are attached to the surface of the current collector foil. The active material layer is disposed on the surface of the current collector foil. The active material layer contains a group of active material particles. The binder particles are dispersed at the interface between the active material layer and the current collector foil.

[0008] According to the first aspect of this disclosure, the adhesive particle group is dispersed at the interface between the active material layer and the current collector foil. Since the adhesive is granular rather than film-like, many active material particles can have contact points with the current collector foil at the interface between the active material layer and the current collector foil. Therefore, the increase in interfacial resistance associated with the use of the adhesive can be reduced.

[0009] It is believed that when an adhesive film is formed on the surface of a current collector foil, the number of contact points between the adhesive film (surface) and the active material particles tends to decrease. On the other hand, adhesive particles can make point contact with active material particles. Since the adhesive is granular, the number of contact points between the adhesive and the active material particles can be increased. By using a cluster of adhesive particles instead of an adhesive film, high peel strength can be expected with a small amount of adhesive coating.

[0010] In the first aspect of this disclosure, the ratio of the adhesion area of ​​the adhesive particle group to the area of ​​the current collector foil can be 11.4 to 19.3%.

[0011] According to the first aspect of this disclosure, the "ratio of the adhesion area of ​​the adhesive particle group to the area of ​​the current collector foil" can be simply referred to as the "area ratio". An area ratio of 11.4% or higher is expected to result in improved peel strength. An area ratio of 19.3% or lower is expected to result in reduced interfacial resistance.

[0012] In the first embodiment of this disclosure, the D50 of the adhesive particle group can be smaller than that of the active substance particle group.

[0013] According to the first aspect of this disclosure, by making the size of the binder particles smaller than the size of the active material particles, the contact points between the active material particles and the current collector foil can be increased. Therefore, a reduction in interfacial resistance is expected.

[0014] In the first aspect of this disclosure, the coating amount of the adhesive particle group can be 0.010 to 0.017 mg / cm³. 2 .

[0015] The method for manufacturing an electrode for a lithium-ion battery according to the second aspect of this disclosure includes the following (a) to (c).

[0016] (a) Prepare the current collecting foil.

[0017] (b) Applying adhesive particle clusters to the surface of the current collector foil using a dry method, and

[0018] (c) Following (b) above, an active material particle group is coated onto the surface of the current collector foil, thereby forming an active material layer.

[0019] According to the second aspect of this disclosure, the adhesive particle group can be dispersed without forming an adhesive film by employing a dry coating method.

[0020] In the second aspect of this disclosure, (b) above may include attaching a group of adhesive particles to the surface of the current collector foil by electrostatic force.

[0021] As an example of the dry method, it is possible to use electrostatic force to attach the adhesive particle clusters to the current collector foil.

[0022] In the second aspect of this disclosure, (c) above may include dry coating of active material particle groups.

[0023] For example, when using a wet coating method to apply the active material particle group, the configuration of the binder particle group may change. It is believed that by using a dry coating method to apply the active material particle group, it is easier to maintain the dispersion state of the binder particle group.

[0024] The following describes the implementation methods (hereinafter referred to as "the implementation methods") and embodiments of the present disclosure (hereinafter referred to as "the embodiments"). However, the implementation methods and embodiments do not limit the technical scope of the present disclosure. Attached Figure Description

[0025] Hereinafter, the features, advantages, and technical and industrial significance of embodiments of the present invention will be described with reference to the accompanying drawings, in which the same reference numerals denote the same elements.

[0026] Figure 1 This is a schematic cross-sectional view of the electrode for a lithium-ion battery according to this embodiment.

[0027] Figure 2 This is a rough top view of the adhesive particle cluster.

[0028] Figure 3 This is a rough top view of the adhesive film.

[0029] Figure 4 This is a schematic cross-sectional view of the adhesive film.

[0030] Figure 5 This is a schematic flowchart of the method for manufacturing an electrode for a lithium-ion battery according to this embodiment.

[0031] Figure 6 This is a schematic diagram illustrating an example of a coating method for adhesive particle groups.

[0032] Figure 7 It is a coordinate graph showing the relationship between adhesive coverage and interfacial resistance.

[0033] Figure 8 It is a coordinate graph showing the relationship between adhesive coverage and peel strength. Detailed Implementation

[0034] Definitions of terms, etc.

[0035] In this specification, the descriptions of "possessing," "comprising," "having," and variations thereof (e.g., "consisting of," etc.) are open-ended. Open-ended descriptions may include additional requirements in addition to essential requirements, or they may not include additional requirements. The description of "composed of," is closed-ended. However, even in closed-ended descriptions, incidental additions and incidental requirements unrelated to the technology of this disclosure are generally not excluded. "Substantially composed of," is semi-closed-ended. In semi-closed-ended descriptions, it is permissible to add requirements that do not substantially affect the basic and novel characteristics of the technology of this disclosure.

[0036] In this manual, expressions such as "may also" and "may" do not mean "must" but are used to mean "there is a possibility".

[0037] In this specification, numerical ranges such as "m~n%" include both upper and lower limits unless otherwise specified. That is, "m~n%" represents a numerical range of "m% and below n%". Furthermore, "m% and below n%" includes "greater than m% and less than n%". In addition, any value arbitrarily selected from the numerical range can be used as a new upper or lower limit. For example, a new numerical range can be set by arbitrarily combining values ​​within the numerical range with values ​​described in other parts of this specification, tables, figures, etc.

[0038] In this specification, all numerical values ​​are modified by the term "about". The term "about" may mean, for example, ±5%, ±3%, ±1%, etc. All numerical values ​​may be approximate values ​​that vary depending on the application of the technology disclosed herein. All numbers may be displayed with significant figures. The measured value may be the average of multiple measurements. The number of measurements may be 3 or more, 5 or more, or 10 or more. Generally, it is expected that the more measurements are taken, the more reliable the average value will be. The measured value may be rounded based on the number of significant figures. The measured value may include errors such as the detection limits of the accompanying measuring device.

[0039] In this specification, when a compound is represented by a stoichiometric formula (e.g., "LiCoO2"), the stoichiometric formula is merely a representative example of the compound. Compounds may also have non-stoichiometric compositions. For example, when lithium cobalt oxide is represented as "LiCoO2," unless otherwise specified, lithium cobalt oxide is not limited to a composition ratio of "Li / Co / O = 1 / 1 / 2," and can contain Li, Co, and O in any composition ratio. Furthermore, trace element doping, substitution, etc., are also permitted.

[0040] In this specification, unless otherwise specified, the order of execution of the various steps, actions, and operations included in the methods is not limited to the order in which they are described. For example, multiple steps may be performed simultaneously. For example, multiple steps may be performed consecutively.

[0041] In this instruction manual, "electrode" is a general term for both positive and negative electrodes. An electrode can be either positive or negative.

[0042] In this specification, "D50" refers to the particle size at which the cumulative frequency from the smallest particle size side reaches 50% in a volume-based particle size distribution. A volume-based particle size distribution can be obtained, for example, using laser diffraction scattering.

[0043] In this specification, "dry method" refers to a coating method in which the solid content of the coating is 90% or more. In a dry method, the solid content of the coating can be, for example, 95% to 100%. "Wet method" refers to a coating method in which the solid content of the coating is less than 90%. In a wet method, the solid content of the coating can be, for example, 50% to 85%. "Solid content ratio" refers to the mass ratio of solid content to the total mass of the coating.

[0044] Electrodes for lithium-ion batteries

[0045] Figure 1 This is a schematic cross-sectional view of the electrode for a lithium-ion battery according to this embodiment. Hereinafter, "electrode for a lithium-ion battery according to this embodiment" may be simply referred to as "this electrode". The electrode 10 is sheet-shaped. The electrode 10 includes a current collector foil 11, a group of binder particles 12, and an active material layer 13. The binder particle group 12 and the active material layer 13 may be disposed on only one side of the current collector foil 11, or they may be disposed on both sides of the current collector foil 11.

[0046] This electrode 10 can have high peel strength. For example, the peel strength between the active material layer 13 and the current collector foil 11 can be 1 N / m or higher. For example, the peel strength between the active material layer 13 and the current collector foil 11 can be 1 to 3.5 N / m. This electrode 10 can have low interfacial resistance. For example, the interfacial resistance between the active material layer 13 and the current collector foil 11 can be 0.0033 Ω / cm. 2 The interfacial resistance between the active material layer 13 and the current collector foil 11 can be, for example, 0.0011 to 0.0033 Ω / cm. 2 .

[0047] Current collector foil

[0048] The current collector foil 11 is conductive. The current collector foil 11 is sheet-like. The current collector foil 11 supports the active material layer 13. The current collector foil 11 comprises a metal foil. The current collector foil 11 may contain at least one selected from, for example, aluminum foil, aluminum alloy foil, copper foil, copper alloy foil, nickel foil, titanium foil, and stainless steel foil. The thickness of the current collector foil 11 may be, for example, 5–50 μm or 10–25 μm.

[0049] Adhesive particle clusters

[0050] Adhesive particle clusters 12 are dispersed at the interface between the active material layer 13 and the current collector foil 11. Figure 2This is a schematic top view of the adhesive particle group 12. The adhesive particle group 12 is attached to the surface of the current collector foil 11. On the surface of the current collector foil 11, the adhesive particle group 12 is distributed in an island-like pattern. Each island-like portion can be a single adhesive particle or an aggregate of multiple adhesive particles. The distribution of the island-like portions can be regular or random. It is assumed that the active material particles can contact the current collector foil 11 in the gaps between the island-like portions. The gaps between the island-like portions can also be, for example, the amount of more than one adhesive particle.

[0051] On the surface of the current collector foil 11, the coating amount of the adhesive particle group 12 can be, for example, 0.010 to 0.017 mg / cm³. 2 The coating weight represents the mass per unit area (adhesive amount). The coating weight of the adhesive particle group 12 can, for example, be 0.010–0.014 mg / cm³. 2 It can also be 0.014–0.017 mg / cm³. 2 .

[0052] On the surface of the current collector foil 11, the area ratio of the adhesive particle group 12 can be, for example, 50% or less, 30% or less, or 20% or less. The area ratio of the adhesive particle group 12 can be, for example, 11.4% to 19.3%. With an area ratio of 11.4% or more, improved peel strength is expected. With an area ratio of 19.3% or less, reduced interfacial resistance is expected. The area ratio of the adhesive particle group 12 can be, for example, 11.4% to 15.9%, or 15.9% to 19.3%.

[0053] The area ratio can be calculated using the following equations (I) to (IV).

[0054] M = c × S0…(I)

[0055] V=M÷ρ...(II)

[0056] S1=V÷T...(III)

[0057] F = S1 ÷ S0 × 100…(IV)

[0058] “M” represents the mass of the adhesive particle group [mg].

[0059] “c” indicates the coating amount of the adhesive particle group [mg / cm³]. 2 ].

[0060] “S0” indicates the area of ​​the current collector foil [cm²] 2 ].

[0061] “V” represents the volume of the adhesive particle group [cm] 3 ].

[0062] “ρ” represents the density of the binder particle cluster [g / cm³]. 3 ].

[0063] “T” indicates the coating thickness [μm] of the adhesive particle group.

[0064] “F” indicates the area ratio [%).

[0065] Figure 3 This is a schematic top view of the adhesive film. The adhesive film 14 covers the surface of the current collector foil 11. In order to form a contact between the active material particles and the current collector foil 11, the adhesive film 14 may be configured as a strip, for example.

[0066] Figure 4 This is a schematic cross-sectional view of the adhesive film. Active material particles are in contact with the current collector foil 11 through the gaps between each other in the adhesive film 14. However, it is considered that the active material particles disposed on the adhesive film 14 have difficulty contacting the current collector foil 11. Even if the adhesive film 14 is formed in a strip shape, the desired interfacial resistance cannot be obtained.

[0067] The binder particle group 12 is an aggregate of multiple binder particle groups. The D50 of the binder particle group 12 can be, for example, 10–1000 nm, 50–500 nm, or 100–200 nm. The D50 of the binder particle group 12 can be smaller than that of the active material particle group. By making the size of the binder particle group smaller than that of the active material particles, the contact points between the active material particles and the current collector foil 11 can be increased. Therefore, a reduction in interfacial resistance is expected. The D50 of the binder particle group 12 can be less than 1 / 10 or less than 1 / 20 of the D50 of the active material particle group. The D50 of the binder particle group 12 can be greater than 1 / 100 of the D50 of the active material particle group.

[0068] The adhesive particle group may contain optional components. The adhesive particle group may contain at least one selected from, for example, polyvinylidene fluoride (PVdF), polyvinylidene fluoride-hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), carboxymethyl cellulose (CMC), polyacrylic acid (PAA), polyamide (PAI), and polyimide (PI).

[0069] active material layer

[0070] An active material layer 13 is disposed on the surface of the current collector foil 11. The thickness of the active material layer 13 can be, for example, 10–500 μm or 50–200 μm. The active material layer 13 contains a group of active material particles. In addition to the group of active material particles, the active material layer 13 may also contain conductive materials, binders, solid electrolytes, etc.

[0071] Active substance particle cluster

[0072] An active substance particle swarm is an aggregate of multiple active substance particles. The D50 of an active substance particle swarm can be, for example, 1–30 μm or 3–10 μm.

[0073] The active material particles may, for example, contain a positive electrode active material. These active material particles may contain at least one selected from, for example, LiCoO2, LiNiO2, LiMnO2, LiMn2O4, Li(NiCoMn)O2, Li(NiCoAl)O2, and LiFePO4. For example, in "Li(NiCoMn)O2", "(NiCoMn)" indicates that the total proportions within the parentheses are 1. As long as the total is 1, the amounts of each component are arbitrary. Li(NiCoMn)O2 may contain, for example, Li(Ni... 1 / 3 Co 1 / 3 Mn 1 / 3 O2, Li(Ni) 0.5 Co 0.2 Mn 0.3 O2, Li(Ni) 0.8 Co 0.1 Mn 0.1 O2, etc.

[0074] The active material particles may include, for example, a negative electrode active material. These active material particles may include, for example, materials selected from graphite, soft carbon, hard carbon, silicon, silicon oxide, silicon-based alloys, tin, tin oxide, tin-based alloys, and Li₄Ti₅O. 12 At least one of them.

[0075] Other ingredients

[0076] The active material layer 13 may also include a binder. The amount of binder relative to 100 parts by weight of the active material particle group may be, for example, 0.1 to 10 parts by weight. The binder in the active material layer 13 may be granular or film-like. The binder may include, for example, PVdF, CMC, SBR, etc.

[0077] The active material layer 13 may also contain a conductive material. The amount of conductive material relative to 100 parts by mass of the active material particle group may be, for example, 0.1 to 10 parts by mass. The conductive material may include, for example, conductive carbon particles, conductive carbon fibers, etc. The conductive material may contain at least one selected from, for example, carbon black, vapor-grown carbon fibers, carbon nanotubes, and graphene sheets. The carbon black may contain, for example, at least one selected from, for example, acetylene black, furnace black, channel black, and thermal cracking black.

[0078] The active material layer 13 may also contain a solid electrolyte. The solid electrolyte may contain at least one selected from, for example, Li₂S-P₂S₅, LiI-Li₂S-P₂S₅, LiBr-Li₂S-P₂S₅, and LiI-LiBr-Li₂S-P₂S₅.

[0079] Composite

[0080] For example, active material particles can be composited with other solid materials (adhesives, conductive materials, etc.). For instance, composite particles can be formed by mixing active material particles with other solid materials under strong shear stress. In the composite particles, for example, adhesives and conductive materials can be attached to the surface of the active material particles.

[0081] Manufacturing method of electrodes for lithium-ion batteries

[0082] Figure 5 This is a simplified flowchart of the manufacturing method of the electrode for a lithium-ion battery according to this embodiment. Hereinafter, "the manufacturing method of the electrode for a lithium-ion battery according to this embodiment" may be simply referred to as "this manufacturing method". This manufacturing method includes "(a) preparation of the current collector foil", "(b) coating of the binder particle group", and "(c) coating of the active material particle group". This manufacturing method may also include, for example, "(d) fixing".

[0083] (a) Preparation of current collector foil

[0084] This manufacturing method includes the step of preparing the current collector foil 11. Details of the current collector foil 11 are as described above.

[0085] (b) Coating of adhesive particle groups

[0086] This manufacturing method includes a step of dry coating adhesive particle group 12 (powder) onto the surface of current collector foil 11. For example, electrostatic printing technology, electrostatic coating technology, or similar technologies can be used.

[0087] Figure 6 This is a schematic diagram illustrating an example of a coating method for adhesive particle groups. For example, the adhesive particle groups can be coated using electrostatic screen printing. Adhesive particle groups 12 are disposed on a screen 101. The screen 101 is conductive. Multiple through-holes are formed in the screen 101. A current collector foil 11 is disposed below the screen 101. A power source 102 applies a DC voltage between the current collector foil 11 and the screen 101. This creates an electric field (E) between the screen 101 and the current collector foil 11. Charge (q) is injected from the screen 101 into the adhesive particle groups 12. That is, the adhesive particle groups 12 become charged. The printing brush 103 flattens the adhesive particle groups 12, introducing the electric field into the adhesive particle groups 12. In the electric field, an electrostatic force (F = qE) acts on the adhesive particle groups 12. Through this electrostatic force, the adhesive particle groups 12 can be attached to the surface of the current collector foil 11. For example, the coating pattern can be controlled by the pattern of the through-holes in the screen 101. That is, the desired distribution state can be formed.

[0088] The coating thickness (packing thickness) of the adhesive particle group 12 can be, for example, 0.1 to 3 μm or 0.1 to 1 μm.

[0089] (c) Coating of active substance particle clusters

[0090] This manufacturing method includes a process of forming an active material layer 13 by coating an active material particle group (powder) onto the surface of a current collector foil 11 after coating an adhesive particle group 12.

[0091] The active material particle group can be coated using any method. For example, a slurry containing the active material particle group can be prepared. For example, the slurry can be coated onto the surface of the current collector foil 11 using a die coater or the like. For example, a wet powder containing the active material particle group can be prepared. For example, the wet powder can be coated onto the surface of the current collector foil 11 using a roller coater or the like. The wet powder can also be referred to as a granule.

[0092] Similar to the binder particle group, the active material particle group can also be dry-coated. It is believed that by also using a dry coating method for the active material particle group, it is easier to maintain the dispersion state of the binder particle group.

[0093] For example, composite particles can be formed by combining active material particles, conductive materials, and binders. By using a dry coating process to apply the composite particle group (powder), a uniformly composed active material layer 13 can be formed. This is because it is believed that the positional relationship between the active material particles, conductive materials, and binders is not easily changed during the formation process of the active material layer 13. In a wet process, during the formation of the active material layer 13, for example, the binder moves together with the solvent (liquid), which tends to cause compositional deviations.

[0094] (d) Fixed

[0095] This manufacturing method can fix the active material layer 13 to the current collector foil 11 by subjecting the active material layer 13 to at least one of heat and pressure. By fixing the active material layer 13 to the current collector foil 11, improved peel strength is expected.

[0096] Pressure and heat can be applied separately. Alternatively, pressure and heat can be applied substantially simultaneously. For example, the active material layer 13 can be compressed using hot rollers, heating plates, etc. The heating temperature of the active material layer 13 can be, for example, near the melting point of the adhesive. The heating temperature can be, for example, 80–200°C, 120–200°C, or 140–180°C.

[0097] For example, the pressure can be adjusted according to the target thickness, target density, etc. of the active material layer 13. For example, a pressure of 50 to 200 MPa can be applied to the active material layer 13.

[0098] As described above, this electrode 10 can be manufactured. This electrode 10 can be cut into a predetermined planar shape according to the specifications of the battery.

[0099] Electrode manufacturing

[0100] Electrodes No. 1 to No. 5 were manufactured in the following locations.

[0101] No.1

[0102] Prepare the following materials.

[0103] Active material particle group: Li(NiCoMn)O2, particle size range = 3~10μm

[0104] Conductive material: Acetylene black

[0105] Adhesive particle size distribution: PVdF, D50 = 150 nm, density = 1.76 g / cm³ 3

[0106] Current collector foil: Al foil, thickness = 12μm

[0107] Prepare an electrostatic screen printing machine (manufactured by Bellco Industrial Co., Ltd.). The distance between the screen 101 and the current collector foil 11 is 1 cm. An electric field is formed by applying a DC voltage of 1.5 kV between the screen 101 and the current collector foil 11. Adhesive particle clusters 12 are coated onto the surface of the current collector foil 11 using electrostatic screen printing (see reference). Figure 6 That is, the adhesive particle group 12 is applied using a dry coating method. The coating weight of the adhesive particle group 12 is 0.007 mg / cm³. 2 The coating thickness of the adhesive particle group 12 is 0.5 μm.

[0108] Prepare a mixing device called "Multipurpose Mixer" manufactured by Japan Coxs Industries, Ltd. This device includes a spherical tank (mixing vessel). Through the convection-promoting effect of the spherical tank, strong shear force is generated, causing solid materials to combine.

[0109] The active material particles, conductive material, and binder are added to a spherical container. The material ratio is "active material particles / conductive material / binder = 90 / 5 / 5 (mass ratio)". The stirring blade speed is set to 10,000 rpm. The materials are mixed for 10 minutes. Composite particles are formed by attaching the conductive material and binder to the surface of the active material particles.

[0110] The composite particle group is coated onto the surface of the current collector foil 11 using electrostatic screen printing (dry method). This forms the active material layer 13, thus fabricating the electrode 10.

[0111] The electrode 10 is held between two heating plates (flat plates). The temperature of the heating plates is 160°C. A load of 15tf is applied to the active material layer 13 through the heating plates. Thus, the active material layer 13 is fixed on the current collector foil 11.

[0112] No. 2~4

[0113] As shown in Table 1 below, except for changing the amount of adhesive particle group 12, this electrode 10 is manufactured in the same manner as No.1, and the active material layer 13 is fixed.

[0114] No. 5

[0115] The adhesive solution is prepared by dissolving adhesive particles in a solvent. The adhesive solution is then applied in strips to the surface of the current collector foil 11 (see reference). Figure 3 , Figure 4 Thus, adhesive film 14 is formed. Electrodes are fabricated in the same manner as in No. 1, except as described above.

[0116] Electrode evaluation

[0117] The peel strength between the active material layer 13 and the current collector foil 11 was determined by a 90-degree peel test.

[0118] The interfacial resistance between the active material layer 13 and the current collector foil 11 was measured using an electrode resistance measurement system (model "RM2610", manufactured by HIOKI).

[0119] Table 1

[0120]

[0121] Figure 7 This is a graph showing the relationship between adhesive coating amount and interfacial resistance. As the coating amount increases, the interfacial resistance tends to increase.

[0122] Figure 8 This is a graph showing the relationship between adhesive coating weight and peel strength. By dry-coating the adhesive particle group, a tendency to obtain high peel strength with a smaller coating weight can be observed. That is, compared to the wet method, the dry method can reduce the amount of adhesive coating. Therefore, it is believed that dry-coating the adhesive particle group can reduce the increase in interfacial resistance (see reference). Figure 7 ).

[0123] appendix

[0124] This specification also supports lithium-ion batteries. Lithium-ion batteries include this electrode. Low battery resistance is expected in lithium-ion batteries because of the low interfacial resistance between the active material layer and the current collector foil in this electrode. Lithium-ion batteries can be liquid-based or all-solid-state batteries.

[0125] This embodiment and this example are exemplary in all respects. This embodiment and this example are not restrictive. The scope of this disclosure includes all modifications within the scope and equivalent meaning of the claims made. For example, any solution extracted from this embodiment and this example and arbitrarily combined thereof is also included in the initial disclosure.

Claims

1. An electrode for lithium-ion batteries, characterized in that, Include: Current collector foil, Adhesive particle groups, and Active material layer, The adhesive particle clusters adhere to the surface of the current collector foil. The active material layer is disposed on the surface of the current collector foil. The active material layer contains a group of active material particles. The adhesive particle group is dispersed at the interface between the active material layer and the current collector foil. The D50 of the adhesive particle group is smaller than that of the active substance particle group.

2. The electrode according to claim 1, characterized in that, The ratio of the adhesion area of ​​the adhesive particle group to the area of ​​the current collector foil is 11.4 to 19.3%.

3. The electrode according to claim 1 or 2, characterized in that, The coating amount of the adhesive particle group is 0.010–0.017 mg / cm³. 2 .

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