Negative electrode material, method for producing same, and secondary battery comprising same

Abstract

Disclosed are: a negative electrode material capable of reducing the risk of explosion of a secondary battery; a method for producing same; and a secondary battery comprising same. The method for producing a negative electrode material may comprise: a step for forming a laminate in which a plurality of layers, formed by binding a negative electrode active material by means of a binder, are laminated; a step for slicing the laminate at an angle not parallel to the stacking boundary and thereby producing laminate slices; a step for pulverizing the laminate slices to form particles of the negative electrode active material; and a step for attaching the negative electrode active material particles to a negative electrode current collector.

Description

Negative electrode material, method for manufacturing the same, and secondary battery including the same

[0001] The present invention relates to a negative electrode material, a method for manufacturing the same, and a secondary battery including the same, and more specifically, to a negative electrode material capable of reducing the risk of explosion, a method for manufacturing the same, and a secondary battery including the same.

[0002] Today, with the advancement of the information age, mobile electronic devices owned by individuals are becoming widely used. These mobile electronic devices inevitably require batteries to operate.

[0003] In the past, primary batteries, such as manganese batteries and alkaline batteries, were mainly used, which were used once and discarded when discharged. However, recently, secondary batteries, which can be recharged after discharge and used repeatedly, are being widely used instead of primary batteries, which are disadvantageous in terms of environmental pollution and cost of discarded batteries.

[0004] These secondary batteries typically consist of a cathode, anode, electrolyte, and separator. Among these, the cathode and anode are the most crucial materials that determine the battery's capacity, lifespan, and charging speed. The cathode, as a lithium-ion source, determines the battery's capacity and average voltage, while the anode determines the charging speed and lifespan.

[0005] When charging, the lithium ions in the positive electrode material move toward the negative electrode material, and the negative electrode active material stores these lithium ions. When discharging, the lithium ions in the negative electrode active material move toward the positive electrode material.

[0006] At this time, when the negative electrode active material stores lithium ions, the volume increases, and conversely, when it releases them, the volume decreases. If the number of charge and discharge cycles increases in this way, the secondary battery may be damaged, increasing the risk of explosion.

[0007] [Prior Art Literature]

[0008] [Patent Document]

[0009] (Patent Document 1) Republic of Korea Publication No. 10-2022-0167669

[0010] Accordingly, the problem that the present invention seeks to solve is to provide a negative electrode material that can reduce the risk of secondary battery explosion.

[0011] Another problem that the present invention seeks to solve is to provide a method for manufacturing such a negative electrode material.

[0012] Another problem that the present invention seeks to solve is to provide a secondary battery including such a negative electrode material.

[0013] According to an exemplary embodiment of the present invention for solving these problems, a negative electrode material includes a negative electrode active material sheet and a negative electrode current collector. The negative electrode active material sheet has negative electrode active material particles and a binder on the inside, and negative electrode active material particles are bonded to neighboring negative electrode active material particles by the binder, and a gap is formed between the negative electrode active material particles. The negative electrode current collector is attached to one surface of the negative electrode active material sheet.

[0014] As an example, the negative electrode collector plate may be surface-treated to blacken.

[0015] As an example, the negative electrode active material may include at least one of graphite, silicon, and tin.

[0016] As an example, the negative electrode active material may be of flake type.

[0017] As an example, the long axis of the negative electrode active material may be perpendicular to the surface of the negative electrode collector plate or may be inclined at a certain angle.

[0018] As an example, the binder may include at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber.

[0019] As an example, the negative electrode active material sheet may be bonded to the negative electrode current collector plate through a polymer resin.

[0020] As an example, the surface of the negative electrode active material sheet in contact with the polymer resin may be surface modified.

[0021] As an example, the surface modification can be achieved by spraying a sodium-based liquid.

[0022] A method for manufacturing a negative electrode material according to an exemplary embodiment of the present invention may include a step of forming a laminate in which a plurality of layers are formed by bonding a negative electrode active material with a binder, a step of forming laminate slices by slicing at an angle that is not parallel to a laminate boundary, a step of forming negative electrode active material particles by crushing the laminate slices, and a step of attaching the negative electrode active material particles to a negative electrode current collector.

[0023] As an example, the step of forming the laminate slice may be performed by a slicing process performed in a direction perpendicular to the laminate boundary surface.

[0024] As an example, the step of forming the laminate slice may be performed by a planing operation performed in a direction forming an acute angle with the laminate boundary surface.

[0025] As an example, the step of forming a laminate in which a plurality of layers are formed by bonding a negative electrode active material with a binder may include the steps of forming a first slurry by mixing a negative electrode active material, a first binder, and a first solvent, coating the first slurry on a base film, removing the base film after drying, laminating each layer, and pressing each of the laminated layers.

[0026] As an example, the negative electrode active material may include at least one of graphite, silicon, and tin, the first binder may include at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber, and the first solvent may be NMP (N-Methyl-2-Pyrrolidone).

[0027] As an example, the step of forming a laminate in which a plurality of layers are formed by combining a negative electrode active material with a binder may include a step of forming a powder by mixing a negative electrode active material and a binder, a step of applying the powder to a base film, a step of removing the base film after heating, a step of laminating each layer, and a step of pressing each of the laminated layers.

[0028] As an example, the negative electrode active material may include at least one of graphite, silicon, and tin, and the binder may include at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber.

[0029] As an example, the method for manufacturing a negative electrode material may further include, after the step of crushing the laminate slices to form negative electrode active material particles, a step of classifying the negative electrode active material particles by size.

[0030] As an example, the step of attaching the negative electrode active material particles to the negative electrode current collector may include the step of forming a second slurry by mixing the negative electrode active material particles, a second binder, and a second solvent, the step of coating the second slurry on the negative electrode current collector, and the step of removing the second solvent by drying.

[0031] As an example, the second binder may be at least one of SBR (styrene butadiene rubber) and CMC (carboxy methylcellulose), and the second solvent may be water.

[0032] As an example, the step of attaching the negative electrode active material particles to the negative electrode current collector may include the steps of charging the negative electrode active material particles with a negative charge and spraying them onto a metal base, performing heating and pressurization to form a negative electrode active material sheet in which the negative electrode active material particles are bonded to each other, and attaching the negative electrode active material sheet to the negative electrode current collector.

[0033] As one embodiment, the method for manufacturing a negative electrode material may further include a step of surface-modifying one surface of the negative electrode active material sheet before the step of attaching the negative electrode active material sheet to the negative electrode current collector.

[0034] As an example, the step of surface-modifying one side of the negative electrode active material sheet can be performed by spraying a sodium-based liquid onto one side of the negative electrode active material sheet.

[0035] As an example, the sodium series liquid may be a sodium ammonia solution or a sodium naphthalene solution.

[0036] As an example, the step of attaching the negative electrode active material sheet to the negative electrode current collector may be performed using a polymer resin adhesive.

[0037] As an example, the step of attaching the negative electrode active material sheet to the negative electrode current collector can be performed by applying vibration while the negative electrode active material sheet is in contact with the negative electrode current collector.

[0038] At this time, the frequency of the vibration may be in the range of 10 KHz to 10 MHz.

[0039] As an example, the method for manufacturing a negative electrode material may further include, after the step of attaching the negative electrode active material particles to the negative electrode current collector, a step of performing a pressing process to control the gap between the negative electrode active material particles.

[0040] A method for manufacturing a negative electrode material according to an exemplary embodiment of the present invention includes a step of arranging a negative electrode active material sheet on top of a negative electrode current collector plate and a step of applying vibration to the negative electrode active material sheet.

[0041] For example, the frequency of the vibration may range from 10 KHz to 10 MHz.

[0042] A secondary battery according to an exemplary embodiment of the present invention includes a negative electrode material, a positive electrode material, an electrolyte, and a separator. The negative electrode material can be manufactured by any of the methods mentioned above. The positive electrode material is disposed spaced apart from the negative electrode material. The electrolyte is disposed between the negative electrode material and the positive electrode material. The separator is disposed in the electrolyte to separate the positive electrode from the negative electrode.

[0043] In one embodiment, the positive electrode material includes a positive electrode current collector plate and a positive electrode active material layer. The positive electrode current collector plate may have a plate shape. The positive electrode active material layer is formed on one surface of the positive electrode current collector plate, and a positive electrode active material, a conductive material, and a binder are mixed.

[0044] As an example, the cathode active material may be LiCoO2, LiNiCoMnO2, LiMnO4, LZO-NCM (LiNi coated with Li2O-ZrO2). X Co y Mn z O2), NMC, and may include at least one of them.

[0045] As an example, the conductive material may include at least one of carbon black, acetylene black, VGCF (Vapor grown carbon fiber), CNT, and graphene.

[0046] In this way, according to the negative electrode material of the present invention, the expansion of the negative electrode active material is accommodated by the pores, thereby preventing the explosion of the secondary battery.

[0047] Figure 1 is a flowchart illustrating a method for manufacturing a negative electrode material according to an exemplary embodiment of the present invention.

[0048] FIG. 2 is a flowchart illustrating detailed steps according to one embodiment of step S110 illustrated in FIG. 1.

[0049] FIG. 3 is a flowchart illustrating detailed steps according to another embodiment of step S110 illustrated in FIG. 1.

[0050] FIG. 4 is a flowchart illustrating detailed steps according to one embodiment of step S150 illustrated in FIG. 1.

[0051] FIG. 5 is a flowchart illustrating detailed steps according to one embodiment of step S150 illustrated in FIG. 1.

[0052] FIG. 6 is a cross-sectional view conceptually illustrating one embodiment of step S120 illustrated in FIG. 1.

[0053] FIG. 7 is a cross-sectional view conceptually illustrating another embodiment of step S120 illustrated in FIG. 1.

[0054] Figure 8 is a conceptual diagram illustrating each step illustrated in Figure 5.

[0055] Figures 9 and 10 are conceptual diagrams illustrating steps S150 and S160, respectively, illustrated in Figure 1.

[0056] Figure 11 is a conceptual diagram illustrating step S530 of Figure 5.

[0057] Fig. 12 is a conceptual diagram illustrating one embodiment of step S540 of Fig. 5.

[0058] Figure 13 is a schematic diagram of a secondary battery according to an exemplary embodiment of the present invention.

[0059] The present invention is susceptible to various modifications and takes various forms. Specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. Throughout the description of each drawing, similar reference numerals have been used to designate similar components. In the accompanying drawings, the dimensions of structures may be exaggerated to enhance clarity of the present invention.

[0060] While terms like "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0061] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. In addition, the meaning of A and B being "connected" or "coupled" includes a case where, in addition to A and B being directly connected or coupled, another component C is included between A and B so that A and B are connected or coupled.

[0062] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be construed in an idealized or overly formal sense unless explicitly defined herein. Furthermore, in the claims for method inventions, the order of the steps may be interchanged, unless the order of the steps is explicitly stated.

[0063] Additionally, the configurations individually described in each embodiment may also be applied in other embodiments.

[0064] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

[0065] Figure 1 is a flowchart illustrating a method for manufacturing a negative electrode material according to an exemplary embodiment of the present invention.

[0066] Referring to FIG. 1, according to a method for manufacturing a negative electrode material according to an exemplary embodiment of the present invention, first, a layer formed by bonding a negative electrode active material with a binder is formed to form a laminate in which multiple layers are laminated (step S110). Hereinafter, step S110 will be described in more detail with reference to FIGS. 2 and 3.

[0067] FIG. 2 is a flowchart illustrating detailed steps according to one embodiment of step S110 illustrated in FIG. 1.

[0068] Referring to FIG. 2, as an example, in order to form a laminate in which a plurality of layers are formed by combining a negative electrode active material with a binder, a negative electrode active material, a first binder, and a first solvent are first mixed to form a first slurry (step S210).

[0069] Thereafter, the first slurry is coated on the base film (step S220), and after drying, the base film is removed (step S230). Through this process, each layer can be formed, and each layer thus formed can be laminated (step S240), and each laminated layer can be pressed (step S250). Through this pressing process, the bonding strength of each layer can be strengthened. Heating may also be performed in parallel during the pressing process.

[0070] As an example, the negative electrode active material may include at least one of graphite, silicon, and tin, the first binder may include at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber, and the first solvent may be NMP (N-Methyl-2-Pyrrolidone). In this way, in addition to a wet process using a solvent, a laminate may also be formed through a dry process performed without a solvent. Hereinafter, a dry process for forming a laminate will be described with reference to FIG. 3.

[0071] FIG. 3 is a flowchart illustrating detailed steps according to another embodiment of step S110 illustrated in FIG. 1.

[0072] Referring to Fig. 3, in order to form a laminate in which a plurality of layers are formed by combining a negative electrode active material with a binder, first, a negative electrode active material and a binder are mixed to form a powder (step S310).

[0073] Thereafter, the powder is applied to the base film (step S320), and after heating, the base film is removed (step S330). In this way, the binder is melted by heating, thereby binding the negative electrode active material. Through this process, each layer can be formed, and each layer thus formed can be laminated (step S340), and each laminated layer can be pressed (step S350). Through this pressing process, the bonding strength of each layer can be strengthened. Heating may also be performed in parallel during the pressing process.

[0074] As described in the above wet process, the negative electrode active material may include at least one of graphite, silicon, and tin, and the binder may include at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber.

[0075] Referring back to FIG. 1, after forming a laminate (step S110), a laminate slice is formed by slicing at an angle that is not parallel to the laminate boundary surface (step S120). For example, the slice may be sliced ​​in a direction perpendicular to the laminate boundary surface (see FIG. 6), or alternatively, the slice may be sliced ​​at an acute angle to the laminate boundary surface (see FIG. 7).

[0076] FIG. 6 is a cross-sectional view conceptually illustrating one embodiment of step S120 illustrated in FIG. 1, and FIG. 7 is a cross-sectional view conceptually illustrating another embodiment of step S120 illustrated in FIG. 1.

[0077] Referring to FIGS. 6 and 7, the laminate (100) is formed by combining individual layers. At this time, each layer may be attached via an adhesive or glue, or may be combined by a molten binder. In addition, a negative electrode active material (110) is dispersed in each layer, and these are combined by a binder.

[0078] The above negative electrode active material (110) is not particularly limited in shape, but in an exemplary embodiment of the present invention, it can be formed in a flat disk-shaped flake type, and the planar shape is not significantly limited.

[0079] This laminate (100) can be sliced ​​along a first slice line (SL1) that is perpendicular to the lamination boundary (FIG. 6), or along a second slice line (SL2) that is at an acute angle to the lamination boundary (FIG. 7). In this case, in the negative electrode material formed through the subsequent process, the long axis of the negative electrode active material is formed to be perpendicular to the surface of the negative electrode collector plate (1100 in FIG. 12) or inclined at a certain angle. Therefore, when the negative electrode active material (110) expands, it expands in a direction parallel to the surface of the negative electrode collector plate (1100) (up-down direction in FIG. 12), and the expansion toward the positive electrode material (2000) is reduced. Accordingly, a short circuit can be prevented, thereby preventing an explosion. At this time, the thickness of the sliced ​​laminate can be formed to be 0.05 to 0.3 mm. If the thickness is too thin, the laminated sheets may separate, making vertical arrangement of the negative electrode active material impossible. If the thickness is too thick, the thickness of the active material layer may be too thick, making the insertion and de-insertion process of lithium difficult, and the contact resistance with the negative electrode current collector plate may increase.

[0080] Meanwhile, such slicing can be performed by a planing machine. In this way, when slicing is performed by a planing machine, thin slicing is possible. That is, when cutting by pressing the cutter in the direction of the first slice line (SL1) or the second slice line (SL2), it is difficult to cut below 0.3 mm.

[0081] Referring again to FIG. 1, after forming the laminate slice (step S120), the laminate slice is pulverized to form negative electrode active material particles (step S130). For example, the particles can be pulverized to a size of 5 to 50 μm.

[0082] Afterwards, the negative electrode active material particles can be optionally classified by size (step S140), and subsequent processes can be performed.

[0083] Thereafter, the above-mentioned negative electrode active material particles are attached to the negative electrode current collector (step S150).

[0084] Meanwhile, the negative electrode collector plate may be surface-treated. These general negative electrode collector plates are formed of copper, and this blackening surface treatment uses Cu2O or CuO to form a rough surface on the negative electrode collector plate. Through this blackening surface treatment, the negative electrode active material particles can be more firmly attached to the negative electrode collector plate.

[0085] Meanwhile, the process of attaching these negative electrode active material particles to the negative electrode current collector (step S150) can be performed in a wet or dry manner, as in the previous process. The process illustrated in FIG. 4 is a wet process, and the process illustrated in FIG. 5 is a dry process. Each process will be described in more detail below with reference to FIGS. 4 and 5.

[0086] FIG. 4 is a flowchart illustrating detailed steps according to one embodiment of step S150 illustrated in FIG. 1.

[0087] Referring to FIG. 4, in order to attach the negative electrode active material particles to the negative electrode current collector, first, the negative electrode active material particles, a second binder, and a second solvent are mixed to form a second slurry (step S410). In one embodiment, the second binder may be at least one of SBR (styrene butadiene rubber) and CMC (carboxy methylcellulose), and the second solvent may be water.

[0088] Thereafter, the second slurry is coated on the negative electrode current collector (step S420) and dried to remove the second solvent.

[0089] FIG. 5 is a flowchart illustrating detailed steps according to one embodiment of step S150 illustrated in FIG. 1.

[0090] Referring to Fig. 5, in order to attach the negative electrode active material particles to the negative electrode current collector, first, the negative electrode active material particles are charged with a negative charge and sprayed onto a metal base (step S510). Thereafter, heating and pressurization are performed to form a negative electrode active material sheet in which the negative electrode active material particles are bonded to each other (step S520), and the negative electrode active material sheet is attached to the negative electrode current collector (step S540).

[0091] Figure 8 is a conceptual diagram illustrating each step illustrated in Figure 5.

[0092] Referring to Fig. 8, first, negatively charged negative electrode active material particles are sprayed onto a metal base (MB) placed on top of a support (SP). At this time, a positive voltage is applied to the support (SP), so that a positive voltage is also applied to the metal base (MB), and accordingly, the negatively charged negative electrode active material particles are guided to the metal base (MB). During the falling process, the negative electrode active material particles tend to be separated from each other by repulsion, and are guided to the metal base (MB), so that the negative electrode active material particles can be relatively evenly distributed.

[0093] Afterwards, pressurization is performed by a pressurizing press (PR) and heat treatment is performed by a heater (H). Pressurization and heating may be performed by the same process.

[0094] Referring again to FIG. 5, before attaching the negative electrode active material sheet to the negative electrode collector (step S540), one surface of the negative electrode active material sheet can be surface modified (step S530).

[0095] Figure 11 is a conceptual diagram illustrating step S530 of Figure 5.

[0096] Referring to FIG. 11, surface modification can be performed by spraying a sodium-based liquid (600) onto one side (e.g., the lower side) of a negative electrode active material sheet (500) on which negative electrode active material particles are attached to each other.

[0097] As an example, the sodium series liquid (600) may be a sodium ammonia solution or a sodium naphthalene solution.

[0098] As an example, the step (S530) of attaching the negative electrode active material sheet to the negative electrode current collector (1100) can be performed using a polymer resin adhesive (700).

[0099] In this embodiment, the negative electrode active material sheet (500) is attached to the negative electrode current collector (1100) through a polymer resin adhesive (700), but the negative electrode active material sheet (500) may be directly attached to the negative electrode current collector (1100) without the polymer resin adhesive (700).

[0100] Hereinafter, a method of directly attaching a negative electrode active material sheet (500) to a negative electrode current collector (1100) will be described in more detail with reference to FIG. 12.

[0101] Fig. 12 is a conceptual diagram illustrating one embodiment of step S540 of Fig. 5.

[0102] Referring to FIG. 12, after the negative electrode active material sheet (500) is brought into contact with the negative electrode current collector (1100), vibration of 10 KHz to 10 MHz is applied to melt the binder of the negative electrode active material sheet and attach it to the negative electrode current collector (1100).

[0103] Referring again to Figure 1, after attaching the negative electrode active material particles to the negative electrode collector (step S150), a pressing process is performed to control the gap between the negative electrode active material particles (step S160). This pressing process is performed at a pressure of 40 to 200 kg / m 2 It can be carried out under pressure of , preferably 60 to 160 kg / m 2It can proceed under the pressure of .

[0104] If the pressure is low, the bonding force between particles is weak, which can cause separation during charging and discharging, leading to instability. On the other hand, if the pressure is high, the bonding force between particles can crack, leading to instability.

[0105] Figures 9 and 10 are conceptual diagrams illustrating steps S150 and S160, respectively, illustrated in Figure 1.

[0106] Referring to FIGS. 9 and 10, the pores (HO) of the negative electrode active material sheet on the negative electrode collector plate (1100) become smaller after pressing.

[0107] Figure 13 is a schematic diagram of a secondary battery according to an exemplary embodiment of the present invention.

[0108] Referring to FIG. 13, a secondary battery according to an exemplary embodiment of the present invention includes a negative electrode material (1000) manufactured by any one of the methods described above, a positive electrode material (2000) disposed spaced apart from the negative electrode material (1000), an electrolyte (EL) disposed between the negative electrode material (1000) and the positive electrode material (2000), and a separator (SM) disposed on the electrolyte (EL) to separate the positive electrode and the negative electrode.

[0109] For example, the positive electrode material (2000) may include a positive electrode current collector (2100) in a plate shape, and a positive electrode active material (2200) formed on one surface of the positive electrode current collector (2100) and containing a mixture of a positive electrode active material, a conductive material, and a binder.

[0110] For example, the positive electrode active material may be LiCoO2, LiNiCoMnO2, LiMnO4, LZO-NCM (LiNi coated with Li2O-ZrO2). X Co y Mn z O2), NMC, and may include at least one of them.

[0111] For example, the conductive material may include at least one of carbon black, acetylene black, VGCF (Vapor grown carbon fiber), CNT, and graphene.

[0112] For example, the positive electrode collector (2100) may include aluminum.

[0113] In this way, according to the negative electrode material of the present invention, the expansion of the negative electrode active material is accommodated by the pores, thereby preventing the explosion of the secondary battery.

[0114] Although the detailed description of the present invention described above has been described with reference to preferred embodiments of the present invention, it will be understood by those skilled in the art or having ordinary knowledge in the art that various modifications and changes can be made to the present invention without departing from the spirit and technical scope of the present invention as set forth in the claims to be described later.

Claims

1. A negative electrode active material sheet having negative electrode active material particles and a binder on the inside, wherein the negative electrode active material particles are bonded to neighboring negative electrode active material particles by a binder, and a void is formed between the negative electrode active material particles; and A negative electrode current collector attached to one side of the above negative electrode active material sheet; A cathode material containing .

2. In paragraph 1, The above negative electrode collector plate is characterized by having a blackened surface treatment.

3. In paragraph 1, A negative electrode material characterized in that the above negative electrode active material comprises at least one of graphite, silicon, and tin.

4. In paragraph 3, A negative electrode material characterized in that the above negative electrode active material is of flake type.

5. In paragraph 4, A negative electrode material characterized in that the long axis of the negative electrode active material is perpendicular to the surface of the negative electrode current collector or inclined at a certain angle.

6. In paragraph 1, A cathode material characterized in that the binder comprises at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber.

7. In paragraph 1, A negative electrode material characterized in that the above negative electrode active material sheet is bonded to the negative electrode current collector plate through a polymer resin.

8. In paragraph 7, A negative electrode material characterized in that the surface of the negative electrode active material sheet in contact with the polymer resin is surface-modified.

9. In paragraph 8, A cathode material characterized in that the above surface modification is achieved by spraying a sodium series liquid.

10. A step of forming a laminate in which a plurality of layers are laminated by combining a negative electrode active material with a binder; A step of forming a laminate slice by slicing at an angle that is not parallel to the laminate boundary surface; A step of crushing the laminated slices to form negative electrode active material particles; and A step of attaching the above negative electrode active material particles to a negative electrode current collector; A method for manufacturing a cathode material including:

11. In paragraph 10, A method for manufacturing a negative electrode material, characterized in that the step of forming the laminated slice is performed by a slicing process performed in a direction perpendicular to the laminated boundary surface.

12. In paragraph 10, A method for manufacturing a negative electrode material, characterized in that the step of forming the laminated slice is performed by a grinding machine performed in a direction forming an acute angle with the laminated boundary surface.

13. In paragraph 10, The step of forming a laminate in which a plurality of layers are laminated by combining a negative electrode active material with a binder is A step of forming a first slurry by mixing a negative electrode active material, a first binder, and a first solvent; A step of coating the first slurry on a base film; After drying, a step of removing the base film; Step of joining each layer; and A step of pressing each laminated layer; A method for manufacturing a cathode material, characterized by including:

14. In paragraph 13, The above negative electrode active material includes at least one of graphite, silicon, and tin, The first binder comprises at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber. A method for manufacturing a negative electrode material, characterized in that the first solvent is NMP (N-Methyl-2-Pyrrolidone).

15. In paragraph 10, The step of forming a laminate in which a plurality of layers are laminated by combining a negative electrode active material with a binder is A step of forming a powder by mixing a negative electrode active material and a binder; A step of applying the above powder to a base film; After heating, a step of removing the base film; Step of joining each layer; and A step of pressing each laminated layer; A method for manufacturing a cathode material, characterized by including:

16. In paragraph 15, The above negative electrode active material includes at least one of graphite, silicon, and tin, A method for manufacturing a negative electrode material, characterized in that the binder comprises at least one of PVDF (Polyvinylidene fluoride), PTFE (Polytetrafluoroethylene), elastomer, and silicone rubber.

17. In paragraph 10, After the step of crushing the laminated slices to form negative electrode active material particles, A method for manufacturing a negative electrode material, characterized in that it further includes a step of classifying negative electrode active material particles by size.

18. In paragraph 10, The step of attaching the above negative electrode active material particles to the negative electrode current collector is: A step of forming a second slurry by mixing the above negative electrode active material particles, a second binder, and a second solvent; A step of coating the second slurry on the negative electrode current collector; and A step of drying to remove the second solvent; A method for manufacturing a cathode material, characterized by including:

19. In paragraph 18, The second binder is at least one of SBR (styrene butadiene rubber) and CMC (carboxy methylcellulose), A method for manufacturing a negative electrode material, characterized in that the second solvent is water.

20. In paragraph 10, The step of attaching the above negative electrode active material particles to the negative electrode current collector is: A step of charging the above-mentioned negative electrode active material particles with a negative charge and spraying them onto a metal base; A step of performing heating and pressurization to form a negative electrode active material sheet in which the negative electrode active material particles are bonded to each other; and A step of attaching the above negative electrode active material sheet to a negative electrode current collector; A method for manufacturing a cathode material, characterized by including:

21. In paragraph 20, Before the step of attaching the above negative electrode active material sheet to the negative electrode current collector, A step of surface modifying one side of the above negative electrode active material sheet; A method for manufacturing a cathode material, characterized in that it further includes:

22. In paragraph 21, The step of surface modifying one side of the above negative electrode active material sheet is: A method for manufacturing a negative electrode material, characterized in that it is performed by spraying a sodium series liquid onto one surface of the above negative electrode active material sheet.

23. In paragraph 22, A method for manufacturing a cathode material, characterized in that the above sodium series liquid is a sodium ammonia solution or a sodium naphthalene solution.

24. In paragraph 21, The step of attaching the above negative electrode active material sheet to the negative electrode current collector is: A method for manufacturing a negative electrode material, characterized in that it is performed using a polymer resin adhesive.

25. In paragraph 20, The step of attaching the above negative electrode active material sheet to the negative electrode current collector is: A method for manufacturing a negative electrode material, characterized in that vibration is applied while the negative electrode active material sheet is in contact with the negative electrode current collector.

26. In paragraph 25, A method for manufacturing a cathode material, characterized in that the frequency of the vibration is in the range of 10 KHz to 10 MHz.

27. In paragraph 10, After the step of attaching the above negative electrode active material particles to the negative electrode current collector, A step of controlling the gap between the negative electrode active material particles by performing a pressing process; A method for manufacturing a cathode material, characterized in that it further includes:

28. A step of placing a negative electrode active material sheet on top of a negative electrode current collector; and A step of applying vibration to the above negative electrode active material sheet; A method for manufacturing a cathode material including:

29. In paragraph 28, A method for manufacturing a cathode material, characterized in that the frequency of the vibration is in the range of 10 KHz to 10 MHz.

30. A negative electrode material manufactured by the method according to any one of claims 10 to 29; A cathode material disposed spaced apart from the cathode material; An electrolyte disposed between the cathode material and the anode material; and A separator disposed in the electrolyte to separate the positive and negative electrodes; A secondary battery containing:

31. In paragraph 30, The above cathode material is, a positive electrode current collector in the shape of a plate; and A positive electrode active material layer formed on one surface of the positive electrode current collector, wherein the positive electrode active material, conductive material, and binder are mixed; A secondary battery characterized by including:

32. In paragraph 31, The above cathode active materials are LiCoO2, LiNiCoMnO2, LiMnO4, LZO-NCM (LiNi coated with Li2O-ZrO2) X Co y Mn z A secondary battery characterized by including at least one of O2) and NMC.

33. In paragraph 31, A secondary battery characterized in that the above conductive material comprises at least one of carbon black, acetylene black, VGCF (Vapor grown carbon fiber), CNT, and graphene.

Images