All-solid-state battery capable of preventing anode separation

Abstract

The invention discloses an all-solid-state battery capable of preventing anode separation, which comprises an anode current collector, an anode layer, a solid electrolyte layer, a cathode layer, a cathode current collector, an anode terminal part and a cathode terminal part, the content of the first adhesive in the first area is greater than the content of the second adhesive in the second area; the anode terminal portion is connected to the anode current collector in the first region. The all-solid-state battery can prevent anode separation during an ultrasonic welding process of connecting an anode terminal portion to an anode current collector.

Description

Technical Field

[0001] The present invention relates to an all-solid-state battery that can prevent anode separation during an ultrasonic welding process of connecting an anode terminal portion to an anode current collector. Background Art

[0002] In the prior art, the manufacturing process of an all-solid-state battery includes using ultrasonic wave to weld the current collector to the terminal portion of the electrode. During the welding process between the current collector and the terminal portion, the current collector may be separated from the electrode in the region adjacent to the terminal portion due to ultrasonic wave energy.

[0003] In order to prevent such separation, the content of the binder in the electrode may be increased to improve the bonding strength of the current collector to the electrode, but when the content of the binder increases, the resistance of the electrode increases, and thus, the output of the battery decreases.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art in this country. Summary of the invention

[0005] In a preferred aspect, the present invention provides an all-solid-state battery that can prevent anode separation while maintaining battery characteristics.

[0006] The term "all-solid-state battery" as used herein refers to a rechargeable secondary battery that includes a solid electrolyte for transporting ions between electrodes of the battery. In a preferred embodiment, the all-solid-state battery of the present invention may be an anode-free lithium-ion battery.

[0007] As used herein, the terms "anode-free lithium-ion cell," "anode-free lithium-ion battery," "anode-free battery," or "anode-free battery" refer to a lithium-ion battery that includes a bare current collector on its anode side, as contrasted with lithium-ion batteries that use lithium metal as the anode.

[0008] In one aspect, an all-solid-state battery is provided, comprising: (1) an anode current collector; (2) an anode layer disposed on the anode current collector; (3) a solid electrolyte layer disposed on the anode layer; (4) a cathode layer disposed on the solid electrolyte layer; (5) a cathode current collector disposed on the cathode layer; (6) an anode terminal connected to the anode current collector; (7) a cathode terminal connected to the cathode current collector, wherein the anode layer comprises: a first region, which is provided as a space between a side surface of the anode layer and a cross section spaced a predetermined distance from the side surface; and a second region, which is provided as a remaining portion of the anode layer except the first region, wherein: the content of the first binder in the first region is greater than the content of the second binder in the second region; and the anode terminal is connected to the anode current collector in the first region. In certain preferred aspects, the anode current collector has a plate-like shape, and the cathode current collector has a plate-like shape.

[0009] On the other hand, the present invention can provide an all-solid-state battery, comprising: an anode collector having a plate-like shape, an anode layer arranged on the anode collector, a solid electrolyte layer arranged on the anode layer, a cathode layer arranged on the solid electrolyte layer, a cathode collector arranged on the cathode layer having a plate-like shape, an anode terminal portion connected to the anode collector, and a cathode terminal portion connected to the cathode collector.

[0010] The term "plate-like shape" or "plate-like" as used herein refers to a three-dimensional shape of a plate, sheet, film or thin layer having a planar surface and a thickness significantly reduced (e.g., millimeter, micrometer or nanometer scale) compared to the width or length of the planar surface.

[0011] The anode layer may include: (i) a first region provided as a space between a side surface of the anode layer and a cross section spaced a predetermined distance from the side surface, and (ii) a second region provided as a remaining portion of the anode layer except the first region.

[0012] The content of the first binder in the first region may be greater than the content of the second binder in the second region.

[0013] The anode termination portion may be connected to the anode current collector in the first region.

[0014] The area of ​​the solid electrolyte layer may be equal to or larger than that of the anode layer, and the area of ​​the cathode layer may be smaller than that of the anode layer.

[0015] The first region may include the first binder in an amount of about 4 wt % to 7 wt % based on the total weight of the first region.

[0016] In a further preferred embodiment, the second region may include the second binder in an amount of about 0.1 wt % to 3 wt %, based on the total weight of the second region.

[0017] The first adhesive and the second adhesive may each independently include one or more selected from styrene butadiene rubber, nitrile rubber, and butadiene rubber.

[0018] The anode layer may further include a reaction region configured to overlap with the solid electrolyte layer and the cathode layer, and a non-reaction region provided as a remaining portion except for the reaction region.

[0019] The length of the first region may be about 50% to 75% of the distance from the side surface to the reaction region.

[0020] The length of the first region may be about 2 mm to 3 mm.

[0021] The adhesive strength between the first region and the anode current collector may be about 0.3 gf / mm to 0.5 gf / mm.

[0022] There is also provided a vehicle comprising an all-solid-state battery as described herein.

[0023] In another aspect, there is provided a method of manufacturing an all-solid-state battery as described herein. The method comprises the steps of forming an anode layer by applying a first slurry on a first region of an anode current collector and applying a second slurry on a second region of the anode current collector.

[0024] The first slurry may suitably include a first binder, a first active material and a first solid electrolyte, and the second slurry may suitably include a second binder, a second active material and a second solid electrolyte. The first slurry includes a first anode active material and a first solid electrolyte in a mass ratio of about 6:4 to 8:2, and the second slurry includes a second anode material and a second solid electrolyte in a mass ratio of about 6:4 to 8:2.

[0025] In another aspect, there is provided a vehicle comprising one or more batteries as disclosed herein.The vehicle of the invention may suitably be electric.

[0026] Other aspects of the invention are discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments shown in the accompanying drawings, which are given hereinafter by way of illustration only and are therefore non-limiting to the present invention, wherein:

[0028] Figure 1 An exemplary all-solid-state battery according to an exemplary embodiment of the present invention is shown;

[0029] Figure 2shows an exemplary anode layer according to an exemplary embodiment of the present invention;

[0030] Figure 3 Shows Figure 2 The length of the first region;

[0031] Figure 4 An exemplary method for manufacturing an anode layer according to an exemplary embodiment of the present invention is shown;

[0032] Figure 5 It shows whether the anode layer according to the comparative example is separated by visual observation;

[0033] Figure 6 It shows whether the anode layer according to the embodiment is separated by visual observation;

[0034] Figure 7 shows the bonding strength between the anode layer and the anode current collector according to the examples and the comparative examples; and

[0035] Figure 8 Shown are charging and discharging curves of the all-solid-state batteries according to the example and the comparative example.

[0036] It should be understood that the accompanying drawings are not necessarily drawn to scale, and they show various preferred features of the basic principles of the invention that are simplified to a certain extent. The specific design features of the present invention as disclosed herein (including, for example, specific dimensions, directions, locations, and shapes) will be determined in part by specific target applications and use environments.

[0037] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. DETAILED DESCRIPTION

[0038] The above objects, other objects, advantages and features of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed herein, but can be implemented in various different forms. The embodiments are provided to make the description of the present invention thorough and to fully convey the scope of the present invention to those skilled in the art.

[0039] In the following description of the embodiment, even if the same elements are depicted in different drawings, they are represented by the same reference numerals. In the accompanying drawings, for the sake of clarity, the size of the structure may be exaggerated compared to its actual size. In the following description of the embodiment, terms such as "first" and "second" can be used to describe various elements, but these elements are not limited. These terms are only used to distinguish an element from other elements. For example, without departing from the scope and spirit of the present invention, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element. Singular expressions can cover plural expressions unless they have significantly different contextual meanings.

[0040] In the following description of the embodiment, terms such as "comprise", "include" and "have" should be interpreted as indicating the presence of the features, numbers, steps, operations, elements or parts or combinations thereof stated in the description, and do not exclude the presence of one or more other features, numbers, steps, operations, elements, parts or combinations thereof, or the possibility of adding them. In addition, it should be understood that when a component (such as a layer, film, region or plate) is referred to as being "on" another component, the component can be directly "on" the other component, or other components can be inserted between the two components. In the same way, it should be understood that when a component (such as a layer, film, region or plate) is referred to as being "below" another component, the component can be directly "below" the other component, or other components can be inserted between the two components.

[0041] All numbers, values ​​and / or expressions used in the specification that represent the amount of components, reaction conditions, polymer compositions and blends are approximate values, which reflect the various uncertainties in the measurements generated when these values ​​are obtained from essentially different objects, so it should be understood that unless otherwise stated, they are modified by the term "about". In addition, unless otherwise stated or obvious from the context, the term "about" as used herein is understood to be within the normal tolerance range of the field, such as within two standard deviations of the mean value. "About" can be understood to be within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05% or 0.01% of the value. Unless the context clearly indicates otherwise, all numerical values ​​provided in this article are modified with the term "about".

[0042] In addition, it should be understood that if a numerical range is disclosed in the specification, the range includes all continuous values ​​from the minimum value of the range to the maximum value, unless otherwise stated. In addition, if such a range involves an integer, the range includes all integers from the minimum integer to the maximum integer, unless otherwise stated. In this specification, when describing the range of a variable, it will be understood that the variable includes all values, including the endpoints described in the range. For example, the range "5 to 10" will be understood to include any sub-range (e.g., 6 to 10, 7 to 10, 6 to 9, 7 to 9, etc.) and 5, 6, 7, 8, 9 and 10 individual values, and will also be understood to include any value between the valid integers in the range, such as 5.5, 6.5, 7.5, 5.5 to 8.5, 6.5 to 9, etc. In addition, for example, the range "10% to 30%" will be understood to include sub-ranges (e.g., 10% to 15%, 12% to 18%, 20% to 30%, etc.) and all integers (including values ​​of 10%, 11%, 12%, 13%, etc. up to 30%), and will also be understood to include any values ​​between the valid integers in the stated range, e.g., 10.5%, 15.5%, 25.5%, etc.

[0043] It should be understood that the term "vehicle" or "vehicle-like" or other similar terms as used herein generally include motor vehicles, such as passenger vehicles including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including various boats and ships, aircraft, etc., and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-petroleum energy sources). As mentioned herein, a hybrid vehicle is a vehicle with two or more power sources, such as a vehicle that has both gasoline power and electric power. In certain preferred aspects, the vehicle can be electric, including a hybrid vehicle, a plug-in hybrid vehicle, or a vehicle with electricity as the primary or sole power source.

[0044] Figure 1 An exemplary all-solid-state battery according to the present invention is shown. Figure 1 In the embodiment, the all-solid-state battery 100 may include: an anode collector 10, an anode layer 20 arranged on the anode collector 10, a solid electrolyte layer 30 arranged on the anode layer 20, a cathode layer 40 arranged on the solid electrolyte layer 30, a cathode collector 50 arranged on the cathode layer 40, an anode terminal portion 60 connected to the anode collector 10, and a cathode terminal portion 70 connected to the cathode collector 50.

[0045] The area of ​​the solid electrolyte layer 30 may be equal to or greater than that of the anode layer 20. In addition, the area of ​​the cathode layer 40 may be smaller than that of the anode layer 20.

[0046] Anode current collector 10 may be a plate-shaped substrate having conductivity. The plate-shaped shape may refer to a three-dimensional shape having at least two main surfaces facing each other. Specifically, anode current collector 10 may have a sheet, a film, or a foil form.

[0047] Anode current collector 10 may include a material that does not react with lithium. Specifically, anode current collector 10 may include at least one selected from nickel (Ni), copper (Cu), stainless steel, and a combination thereof.

[0048] The thickness of the anode current collector 10 is not limited to a specific value, and may be, for example, approximately 1 μm to 500 μm.

[0049] Anode terminal portion 60 may include a metal plate electrically connected to anode current collector 10. Anode terminal portion 60 may be shaped like a rectangular plate, for example. The width of anode terminal portion 60 is not limited to a specific value and may be smaller than the width of anode current collector 10.

[0050] The anode terminal portion 60 may include a metal, such as nickel (Ni) or the like.

[0051] The anode terminal portion 60 may be welded to the anode current collector 10. The welding position of the anode terminal portion 60 is not limited to a specific position, and the anode terminal portion 60 may be welded to one side surface of the anode current collector 10, or an edge of one main surface. The welding method of the anode terminal portion 60 is not limited to a specific method, and may be ultrasonic welding, spot welding, laser welding, etc. In particular, the anode terminal portion 60 may be connected to the anode current collector 10 by ultrasonic welding.

[0052] Figure 2 20 according to an exemplary embodiment of the present invention. Figure 2 In the embodiment, the anode layer 20 may be in the form of a sheet having a predetermined width and length.

[0053] The anode layer 20 may include a first region 21 and a second region 32, the first region 21 being a space between a side surface A of the anode layer 20 and a cross section B spaced a predetermined distance from the side surface A, and the second region 32 being a remaining portion of the anode layer 20 except the first region 21. Specifically, the first region 21 may be a space between the side surface A of the anode layer 20 along the length direction and the cross section B spaced a predetermined distance from the side surface A along the length direction.

[0054] The first region 21 may have a greater content of the binder than the second region 23. Specifically, the content of the first binder in the first region is greater than the content of the second binder in the second region. In order to prevent the anode current collector 10 and the anode layer 20 from being separated in the region adjacent to the anode terminal portion 60 due to ultrasonic energy when the anode terminal portion 60 is ultrasonically welded to the anode current collector 10, the content of the first binder in the first region 21 is increased.

[0055] Therefore, the anode terminal portion 60 may be connected to the anode current collector 10 in the first region 21 .

[0056] The first region 21 may include a first binder in an amount of about 4% to 7% by weight, and the remainder of the anode material, based on the total weight of the first region. The anode material may include an anode active material and a solid electrolyte in a mass ratio of about 6:4 to 8:2. When the content of the first binder in the first region 21 is less than about 4% by weight, the bonding strength between the first region 21 and the anode current collector 10 is reduced, and therefore, when the anode terminal portion 60 is ultrasonically welded to the anode current collector 10, separation of the anode layer 20 may occur. When the content of the first binder in the first region 21 is greater than about 7% by weight, the viscosity of the slurry configured to form the first region 21 may increase, and therefore, it may be difficult to form the first region 21 by coating.

[0057] The second region 23 may include about 0.1 wt % to 3 wt % of the second binder and the remainder of the anode material based on the total weight of the second region. The anode material may include an anode active material and a solid electrolyte in a mass ratio of about 6:4 to 8:2.

[0058] The first adhesive and the second adhesive may each independently include one or more selected from styrene butadiene rubber, nitrile rubber, and butadiene rubber.

[0059] The anode active material may suitably include a carbon-based active material, a silicon-based active material, or a combination thereof.

[0060] The carbon-based active material may appropriately include natural graphite, artificial graphite, and the like.

[0061] The silicon-based active material may suitably include Si, SiO x (0<x<2) etc.

[0062] The solid electrolyte may appropriately include an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or the like.

[0063] The oxide-based solid electrolyte may suitably include perovskite-type LLTO (Li 3x La 2 / 3-x TiO 3 ), phosphate-based NASICON-type LATP (Li 1+x Al x Ti 2-x (PO 4 ) 3 )wait.

[0064] The sulfide-based solid electrolyte may suitably include: Li2S-P 2 S5 , Li 2 SP 2 S 5 -LiI, Li 2 SP 2 S 5 -LiCl, Li 2 SP 2 S 5 -LiBr, Li 2 SP 2 S 5 -Li 2 O. Li 2 SP 2 S 5 -Li 2 O-LiI、Li 2 S-SiS 2 , Li 2 S-SiS 2 -LiI, Li 2 S-SiS 2 -LiBr, Li 2 S-SiS 2 -LiCl, Li 2 S-SiS 2 -B 2 S 3 -LiI, Li 2 S-SiS 2 -P 2 S 5 -LiI, Li 2 SB 2 S 3 , Li 2 SP 2 S 5 -Z m S n (m and n are positive numbers, Z is one of Ge, Zn and Ga), Li 2 S-GeS 2 , Li 2 S-SiS 2 -Li 3 PO 4 , Li 2 S-SiS 2 -Li x MO y (x and y are positive numbers, M is one of P, Si, Ge, B, Al, Ga and In), Li 10 G 2 S 12 wait.

[0065] The anode layer 20 may appropriately include a reaction region 25 and a non-reaction region 27, wherein the reaction region 25 is configured to overlap with the solid electrolyte layer 30 and the cathode layer 40, and the non-reaction region 27 is the remaining portion except for the reaction region 25. The reaction region 25 may represent a portion of the anode layer 20, and the lithium ions (Li ions) released from the cathode layer 40 + ) reaches this portion through the solid electrolyte layer 30, thereby causing an electrochemical reaction with the electrons during charging. The area of ​​the reaction region 25 may be substantially the same as the area of ​​the cathode layer 40.

[0066] Figure 3 The length L of the first region 21 is shown. The length L of the first region 21 may be about 50% to 75% of the distance D from the side surface A to the reaction region 25. The length L of the first region 21 and the distance from the side surface A to the reaction region 25 may both represent the straight-line distance from the start point to the end point in the length direction. When the length L of the first region 21 is less than about 50% of the distance D, the first region 21 is too short, and therefore, when the anode terminal portion 60 is ultrasonically welded, separation of the anode layer 20 may occur. When the length L of the first region 21 is greater than about 75% of the distance D, it may be difficult for the first region 21 not to invade the reaction region 25. Specifically, the length L of the first region 21 may be about 2 mm to 3 mm.

[0067] The bonding strength between the first region 21 and the anode current collector 10 may be equal to or greater than about 0.3 gf / mm. The upper limit of the bonding strength is not limited to a specific value and may be equal to or less than about 0.5 gf / mm. Such bonding strength may be a value measured by a universal testing machine (UTM). This will be described later.

[0068] The solid electrolyte layer 30 may be interposed between the anode layer 20 and the cathode layer 40 , and may include a solid electrolyte having lithium ion conductivity.

[0069] The solid electrolyte may include an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or the like.

[0070] The oxide-based solid electrolyte may suitably include perovskite-type LLTO (Li 3x La 2 / 3-x TiO 3 ), phosphate-based NASICON-type LATP (Li 1+x Al x Ti 2-x (PO 4 ) 3 )wait.

[0071] The sulfide-based solid electrolyte may suitably include: Li 2 SP 2 S5 , Li 2 SP 2 S 5 -LiI, Li 2 SP 2 S 5 -LiCl, Li 2 SP 2 S 5 -LiBr, Li 2 SP 2 S 5 -Li 2 O. Li 2 SP 2 S 5 -Li 2 O-LiI、Li 2 S-SiS 2 , Li 2 S-SiS 2 -LiI, Li 2 S-SiS 2 -LiBr, Li 2 S-SiS 2 -LiCl, Li 2 S-SiS 2 -B 2 S 3 -LiI, Li 2 S-SiS 2 -P 2 S 5 -LiI, Li 2 SB 2 S 3 , Li 2 SP 2 S 5 -Z m S n (m and n are positive numbers, Z is one of Ge, Zn and Ga), Li 2 S-GeS 2 , Li 2 S-SiS 2 -Li 3 PO 4 , Li 2 S-SiS 2 -Li x MO y (x and y are positive numbers, M is one of P, Si, Ge, B, Al, Ga and In), Li 10 G 2 S 12 wait.

[0072] The cathode layer 40 may include a cathode active material, a solid electrolyte, a conductive material, a cathode binder, etc.

[0073] The cathode active material can store and release lithium ions.

[0074] The cathode active material may suitably include: a rock-salt-layer-type active material such as LiCoO 2 , LiMnO 2 , LiNiO 2 , LiVO 2 or Li 1+x Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 ; a spinel-type active material such as LiMn 2 O 4 or Li(Ni 0.5 Mn 1.5 )O 4 ; an inverse-spinel-type active material such as LiNiVO 4 or LiCoVO 4 ; an olivine-type active material such as LiFePO 4 , LiMnPO 4 , LiCoPO 4 or LiNiPO 4 ; a silicon-containing active material such as Li 2 FeSiO 4 or Li 2 MnSiO 4 ; a rock-salt-layer-type active material in which a part of the transition metals are replaced by different kinds of metals, such as LiNi 0.8 Co (0.2-x) Al x O 2 (0 < x < 0.2); a spinel-type active material in which a part of the transition metals are replaced by different kinds of metals, such as Li 1+x Mn 2-x-y M y O 4 (M is at least one of Al, Mg, Co, Fe, Ni or Zn, 0 < x + y < 2); or lithium titanate, such as Li 4 Ti 5 O 12 .

[0075] The solid electrolyte may include an oxide-based solid electrolyte or a sulfide-based solid electrolyte. In particular, a sulfide-based solid electrolyte having high lithium-ion conductivity can be used. The sulfide-based solid electrolyte may suitably include: Li 2 S-P 2 S5 , Li 2 SP 2 S 5 -LiI, Li 2 SP 2 S 5 -LiCl, Li 2 SP 2 S 5 -LiBr, Li 2 SP 2 S 5 -Li 2 O. Li 2 SP 2 S 5 -Li 2 O-LiI、Li 2 S-SiS 2 , Li 2 S-SiS 2 -LiI, Li 2 S-SiS 2 -LiBr, Li 2 S-SiS 2 -LiCl, Li 2 S-SiS 2 -B 2 S 3 -LiI, Li 2 S-SiS 2 -P 2 S 5 -LiI, Li 2 SB 2 S 3 , Li 2 SP 2 S 5 -Z m S n (m and n are positive numbers, Z is one of Ge, Zn and Ga), Li 2 S-GeS 2 , Li 2 S-SiS 2 -Li 3 PO 4 , Li 2 S-SiS 2 -Li x MO y (x and y are positive numbers, M is one of P, Si, Ge, B, Al, Ga and In), Li 10 G 2 S 12The solid electrolyte included in the cathode layer 40 may be the same as or different from the solid electrolyte included in the solid electrolyte layer 30 .

[0076] The conductive material may include carbon black, conductive graphite, ethylene black, graphene, and the like.

[0077] The cathode binder may include butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, polyvinylidene fluoride, polytetrafluoroethylene, and the like.

[0078] The cathode current collector 50 may include a plate-shaped substrate having conductivity. The cathode current collector 50 may include an aluminum foil.

[0079] The thickness of the cathode current collector 50 is not limited to a specific value, and may be, for example, approximately 1 μm to 500 μm.

[0080] The cathode terminal portion 70 may include a metal plate electrically connected to the cathode current collector 50. The shape of the cathode terminal portion 70 may be, for example, a rectangular plate shape.

[0081] The width of the cathode terminal portion 70 is not limited to a specific value, and may be smaller than the width of the cathode current collector 50 .

[0082] The cathode terminal portion 70 may include metal, such as aluminum (Al) or the like.

[0083] The cathode terminal portion 70 may be welded to the cathode current collector 50. The welding position of the cathode terminal portion 70 is not limited to a specific position, and the cathode terminal portion 70 may be welded to one side surface or an edge of one main surface of the cathode current collector 50. The welding method of the cathode terminal portion 70 is not limited to a specific method, and may be ultrasonic welding, spot welding, laser welding, etc. In particular, the cathode terminal portion 70 may be connected to the cathode current collector 50 by ultrasonic welding.

[0084] The anode terminal portion 60 and the cathode terminal portion 70 may be formed at one end of the all-solid-state battery 100 along the same direction. Figure 1 as shown, or may be formed in the opposite direction.

[0085] Example

[0086] Hereinafter, the present invention will be described in more detail by the following examples. The following examples are only used to exemplarily describe the present invention and are not intended to limit the scope of the present invention.

[0087] A first slurry was prepared, which contained about 4.4 wt % of a first binder and the remainder of an anode material. A second slurry was prepared, which contained about 2 wt % of a second binder and the remainder of an anode material. Butadiene rubber was used as the first binder and the second binder. An anode active material and a sulfide-based solid electrolyte were used as the anode material.

[0088] Use a benchtop coater to coat the first slurry and the second slurry on a substrate, such as Figure 4 The dried product is punched so that the length of the first region is about 2 mm to 3 mm, thereby obtaining an anode layer, such as Figure 4 shown.

[0089] After the anode layer is adhered to the anode current collector, the anode terminal is connected to one side surface of the anode current collector by ultrasonic welding. Here, the anode terminal is connected to the side surface of the anode current collector so that the first region is located on one side of the anode terminal.

[0090] A solid electrolyte layer having the same size as the anode layer is stacked on the anode layer, and a cathode layer is stacked on the solid electrolyte layer. A cathode current collector having a cathode terminal portion welded thereto is stacked on the cathode layer, thereby obtaining an all-solid-state battery.

[0091] Comparative Examples

[0092] A slurry containing about 2 wt% of a binder and the balance of an anode material was prepared. Butadiene rubber was used as a binder. An anode active material and a sulfide-based solid electrolyte were used as the anode material.

[0093] The slurry was coated on a substrate using a table coater and dried. The dried product was punched so that the anode layer had the same area as the anode layer according to the example, thereby obtaining an anode layer.

[0094] An all-solid-state battery was manufactured in the same configuration and manner as in the example except that the above-described anode layer according to the comparative example was used.

[0095] Figure 5 It is shown whether the anode layer according to the comparative example is separated or not by visual observation. Figure 6 It is shown whether the anode layer according to the embodiment is separated or not by visual observation. During the process of ultrasonic welding the anode terminal part, the anode layer according to the comparative embodiment is separated, but the anode layer according to the embodiment is not separated.

[0096] Figure 7 The bonding strength between the anode layer and the anode current collector according to the embodiment and the comparative embodiment is shown. The anode layer and the anode current collector according to the embodiment and the comparative embodiment were placed between PET films having a thickness of about 100 μm, and were pressed at a temperature of about 60° C. and a pressure of about 6.5 MPa for about 1 second using a flat press. The obtained resultant product was adhered to a slide glass and mounted on a bracket of a UTM. The force required to separate the anode layer and the corresponding anode current collector from each other was measured by applying a force at a speed of about 300 mm / min. As Figure 7As shown, the adhesive strength between the anode layer according to the embodiment (particularly, the first region of the anode layer) and the anode collector is about 0.38 gf / mm, which is much greater than that between the anode layer according to the comparative embodiment.

[0097] Figure 8 Graphs showing the charge and discharge curves of the all-solid-state battery according to the embodiment and the comparative embodiment. Figure 8 As shown, even if the content of the binder in a predetermined area of ​​the anode layer is increased, the performance of the all-solid-state battery is not affected.

[0098] Therefore, according to various exemplary embodiments of the present invention, separation of the anode layer due to the energy of ultrasonic welding may be resolved without deteriorating the performance of the all-solid-state battery.

[0099] As is apparent from the above description, according to various exemplary embodiments of the present invention, an all-solid-state battery that can prevent anode separation while maintaining battery characteristics can be provided.

[0100] The invention has been described in detail with reference to preferred embodiments. However, those skilled in the art will appreciate that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. An all-solid-state battery, include: Anode current collector, an anode layer disposed on the anode current collector; a solid electrolyte layer disposed on the anode layer; a cathode layer disposed on the solid electrolyte layer; a cathode current collector disposed on the cathode layer; an anode terminal portion connected to the anode current collector; as well as connected to a cathode terminal portion of the cathode current collector, Wherein, the anode layer comprises: a first region provided as a space between a side surface of the anode layer and a cross section spaced a predetermined distance from the side surface; and a second region, which is provided as a remaining portion of the anode layer excluding the first region, in: The content of the first binder in the first region is greater than the content of the second binder in the second region; and The anode termination portion is connected to the anode current collector in the first region.

2. The all-solid-state battery according to claim 1, in, The anode current collector has a plate-like shape, and the cathode current collector has a plate-like shape.

3. The all-solid-state battery according to claim 1, in: The area of ​​the solid electrolyte layer is equal to or greater than the area of ​​the anode layer; and The area of ​​the cathode layer is smaller than that of the anode layer.

4. The all-solid-state battery according to claim 1, in, The first region includes the first binder in an amount of 4 wt % to 7 wt % based on the total weight of the first region.

5. The all-solid-state battery according to claim 1, in, The second region includes the second binder in an amount of 0.1 wt % to 3 wt % based on the total weight of the second region.

6. The all-solid-state battery according to claim 1, in, The first adhesive and the second adhesive each independently include one or more selected from styrene butadiene rubber, nitrile rubber and butadiene rubber.

7. The all-solid-state battery according to claim 1, in: The anode layer further includes a reaction region and a non-reaction region, the reaction region is configured to overlap with the solid electrolyte layer and the cathode layer, and the non-reaction region is configured as a remaining portion except for the reaction region; and The length of the first region is 50% to 75% of the distance from the side surface to the reaction region.

8. The all-solid-state battery according to claim 1, in, The length of the first region is 2 mm to 3 mm.

9. The all-solid-state battery according to claim 1, in, The adhesive strength between the first region and the anode current collector is 0.3 gf / mm to 0.5 gf / mm.

10. A vehicle comprising the all-solid-state battery according to claim 1.

11. A method for manufacturing an all-solid-state battery according to claim 1, wherein include: forming an anode layer by applying a first slurry on a first region of the anode current collector and applying a second slurry on a second region of the anode current collector, The first slurry comprises a first binder, a first active material and a first solid electrolyte, and the second slurry comprises a second binder, a second active material and a second solid electrolyte. 12 . The method according to claim 11 , wherein the first slurry comprises a first anode active material and a first solid electrolyte in a mass ratio of 6:4 to 8:

2. 13 . The method according to claim 12 , wherein the second slurry comprises a second anode material and a second solid electrolyte in a mass ratio of 6:4 to 8:2.

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