Electrode and rechargeable battery including the same

Abstract

Provided are an electrode and a rechargeable battery including the same, a positive electrode for a battery including a substrate and a positive active material layer on at least one surface of the substrate, in which a pore ratio of the positive active material layer is 11 vol% to 16 vol%, and an average particle diameter D50 is 8 [mu] m to 20 [mu] m.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to an electrode and a rechargeable battery including the electrode. Background Art

[0002] Based on the development and demand for mobile devices, the desire and demand for rechargeable batteries as energy sources have increased.

[0003] A rechargeable battery may be formed by impregnating an electrode assembly (an electrode assembly is formed by placing electrodes on both sides of a separator and winding them into a core shape, or an electrode assembly is formed by stacking sheet electrodes and a separator) in a case together with an electrolyte solution, and then closing and sealing the case with a cap assembly.

[0004] Currently, with the development of automobiles (eg, electric vehicles), a high-capacity design having relatively high energy density and relatively fast charging characteristics is desired / required to meet the characteristics of rechargeable batteries used in automobiles.

[0005] For high capacity characteristics, a material with a relatively high specific capacity is applied, or the amount of active material deposited on a substrate is increased by a relatively high loading to form (or provide) a thick film, but as the film thickness increases, it becomes difficult to ensure electrode adhesion or conductivity, ultimately leading to problems of degradation of battery performance and degradation of fast charging characteristics. Summary of the invention

[0006] An aspect of one or more embodiments of the present disclosure is directed to an electrode that can ensure high energy density and simultaneously (eg, concurrently) ensure fast charging characteristics, and a rechargeable battery including the electrode.

[0007] A positive electrode for a battery according to one or more embodiments of the present disclosure includes a substrate and a positive active material layer formed on at least one surface of the substrate, wherein the positive active material layer has a pore ratio of 11 volume percent (vol %) to 16 volume % and an average particle size D50 of 8 micrometers (μm) to 20 μm.

[0008] In one or more embodiments, the loading level (L / L) of the positive electrode active material layer may be 40 mg / cm 2 Up to 60mg / cm 2 .

[0009] In one or more embodiments, the positive active material layer may include first and second pores of different sizes, and a diameter of the first pore is 0.2 μm to 0.5 μm.

[0010] In one or more embodiments, the first pores may be 55 volume % to 65 volume % of the entire pore volume included in the positive active material layer.

[0011] In one or more embodiments, the compression ratio of the positive active material layer may be 69 volume % to 73 volume % (eg, 69:100 to 73:100).

[0012] In one or more embodiments, the substrate may include aluminum.

[0013] A rechargeable battery according to one or more embodiments of the present disclosure includes an electrode assembly including a positive electrode for a battery; a case accommodating the electrode assembly; an electrolyte filled in the case; and a cap assembly coupled to the case and sealing the case.

[0014] In one or more embodiments of the present disclosure, an electrode, a secondary battery cell including the electrode capable of rapid charging, and a rechargeable battery including the secondary battery cell may be provided to increase energy density by performing a high load and thus improving movement characteristics of ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic cross-sectional view of a positive electrode for a rechargeable battery according to one or more embodiments of the present disclosure.

[0016] Figure 2 is a graph of the amount of precipitation measured based on the compression ratio of the positive active material layer according to one or more embodiments of the present disclosure.

[0017] Figure 3 is a graph measuring the pore ratio and compression ratio of a positive active material layer according to one or more embodiments of the present disclosure.

[0018] Figure 4 is a schematic perspective view of a rechargeable battery according to one or more embodiments of the present disclosure.

[0019] Figure 5 According to one or more embodiments of the present disclosure, Figure 4 A cross-sectional view taken along line V-V'.

[0020] Figure 6 is a schematic exploded perspective view of a rechargeable battery according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0021] The present disclosure can be modified in many alternative forms, and therefore specific embodiments will be shown in the drawings and described in more detail. However, it should be understood that this is not intended to limit the present disclosure to the specific form disclosed, but is intended to cover all modifications, equivalents and substitutes that fall within the spirit and scope of the present disclosure. Hereinafter, the present disclosure will be more fully described with reference to the accompanying drawings, in which example embodiments of the disclosure are shown.

[0022] The drawings and description are to be considered illustrative rather than restrictive in nature. Rather, these embodiments are provided as examples so that the disclosure will be thorough and complete and will fully convey the aspects and features of the disclosure to those skilled in the art. Therefore, processes, elements, and techniques that are not necessary for a person of ordinary skill in the art to fully understand the aspects and features of the disclosure may not be described.

[0023] Throughout the specification, the same reference numerals denote the same elements, and repeated descriptions thereof may not be provided.

[0024] In the drawings, the thickness of layers, films, panels, and / or regions, etc., may be exaggerated for clarity. In addition, in the drawings, the thickness of some layers and regions may be exaggerated for better understanding and ease of description.

[0025] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on," "connected to," or "coupled to" another element, it can be directly on, directly connected to, or directly coupled to the other element, or one or more intervening elements may be present. Additionally, it will be understood that when an element is referred to as being "between" two elements, it can be the only element between the two elements, or one or more intervening elements may also be present.

[0026] It will be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the spirit and scope of the present disclosure, the first element, first component, first region, first layer or first part described below may be referred to as the second element, second component, second region, second layer or second part.

[0027] For ease of explanation, spatially relative terms such as "below", "below", "above", etc. may be used herein to describe the relationship of one element or feature to another element or feature as shown in the accompanying drawings. It will be understood that, in addition to the orientation depicted in the figures, spatially relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the accompanying drawings is turned over, the elements described as "below" or "below" other elements or features will then be oriented to be "above" the other elements or features. Therefore, the example terms "below" and "below" can cover both orientations above and below. The device can be oriented otherwise (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0028] It will also be understood that when the terms “comprises,” “includes,” and variations thereof are used in this specification, it indicates the presence of the stated features, integers (integers), steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers (integers), steps, operations, elements, components, and / or groups thereof.

[0029] As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items. Unless otherwise apparent from the disclosure, expressions such as "at least one of ...", "a plurality of ...", "a ..." and other postpositional / prepositional phrases, when followed / preceded by a list of elements, should be understood to include disjunctions if written as a list of conjunctions, and vice versa. For example, the expression "at least one of a, b, and c", "a ..." selected from the group consisting of a, b, and c", "at least one selected from a, b, and c", "at least one from a, b, and c", "from a, b, and c, one from a, b, and c", "at least one from a to c" means only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0030] In the present disclosure, when the particles are spherical, "diameter" means the particle diameter or the average particle diameter, and when the particles are non-spherical, "diameter" means the major axis length or the average major axis length. The particle diameter (or particle size) can be measured using a scanning electron microscope or a particle size analyzer. As a particle size analyzer, for example, HORIBA, LA-950 laser particle size analyzer can be used. When the particle size is measured using a particle size analyzer, the average particle diameter (or particle size) is referred to as D50. D50 refers to the average diameter (or size) of particles whose cumulative volume corresponds to 50% by volume (vol%) in a particle size distribution (e.g., cumulative distribution), and refers to a value corresponding to 50% of the particle size from the smallest particle when the total number of particles in a distribution curve accumulated in the order of the smallest particle size to the largest particle size is 100%.

[0031] Figure 1 is a schematic cross-sectional view of a positive electrode for a rechargeable battery according to one or more embodiments of the present disclosure.

[0032] like Figure 1 As shown in FIG. 1 , a positive electrode 70 for a rechargeable battery according to one or more embodiments includes a substrate 71 and a positive active material layer 72 formed on the substrate 71. The positive active material layer 72 may be formed on one or both surfaces (eg, opposite surfaces) of the substrate 71.

[0033] After the positive active material is coated on the substrate 71 to form the positive active material layer 72, the positive active material layer 72 is compressed and may include pores S. The positive active material may be 40 mg / cm 2 Up to 60mg / cm 2 The positive electrode active material layer is coated at a loading level (L / L) of 69 volume % to 73 volume % and then compressed at a compression ratio of 69 volume % to 73 volume %. The compression ratio is the ratio of the thickness of the active material layer after winding to the thickness of the active material layer before winding (e.g., the thickness of the wound electrode plate / the thickness of the coating). In one or more embodiments, the compression ratio of the positive electrode active material layer (e.g., the ratio or ratio of the volume of the positive electrode active material layer before winding to the volume after winding) is 69 volume % to 73 volume % (e.g., (69:100 to 73:100)×100).

[0034] Figure 2 is a graph measuring the amount of precipitation based on the compression ratio of the positive active material layer according to one or more embodiments of the present disclosure. Figure 3 is a graph measuring the pore ratio and compression ratio of a positive active material layer according to one or more embodiments of the present disclosure.

[0035] Reference Figure 2It can be confirmed that if the compression ratio is in the range of 69% to 73%, the amount of precipitation is 1 weight percent (wt%) or less than 1 weight percent (wt%) (for example, when the compression ratio is in the range of 69% to 73%, the amount of precipitation is 1 weight percent (wt%) or less than 1 weight percent (wt%)), and if the compression ratio is less than 69% or greater than 73%, the amount of precipitation substantially exceeds 1wt% (for example, when the compression ratio is less than 69% or greater than 73%, the amount of precipitation substantially exceeds 1wt%).

[0036] At this time, if Figure 3 As shown in , it can be seen that the pore ratio is in the range of 11 vol % to 16 vol %.

[0037] Fast charging is improved by less lithium precipitation, and in one or more embodiments, the compression ratio is set to 69 vol % to 73 vol % and the pore ratio is maintained at 11 vol % to 16 vol %, thereby maintaining the amount of lithium precipitation at less than 1 wt %.

[0038] The average particle diameter D50 of the positive electrode active material layer 72 (eg, the average particle diameter of particles in the positive electrode active material layer 72 ) may be 8 micrometers (μm) to 20 μm, and the pore ratio may be 11 volume % to 16 volume %.

[0039] The average diameter may be an average particle diameter D50, and unless otherwise defined in the present specification, the average particle diameter D50 refers to a particle diameter having a cumulative volume of 50 volume % in a particle size distribution.

[0040] The average particle diameter D50 can be measured by a method generally available and / or suitable for those of ordinary skill in the art. For example, it can be measured with a particle size analyzer, a transmission electron microscope image, or a scanning electron microscope image. As another method, it can be measured with a device using dynamic light scattering, or data analysis can be performed to count the number of particles for each size range to obtain an average particle diameter D50 value.

[0041] In the positive electrode active material layer 72, pores with a diameter of 0.2 μm to 0.5 μm are called first pores, and the remaining pores outside the diameter size of the first pores are called second pores, and the volume occupied by the first pores relative to the total volume of the pores included in the positive electrode active material layer can be in a ratio of 55 volume % to 65 volume %.

[0042] Figure 4 is a schematic perspective view of a rechargeable battery according to one or more embodiments of the present disclosure. Figure 5 According to one or more embodiments of the present disclosure, Figure 4 A view taken along line V-V'.

[0043] like Figure 4 and Figure 5 As shown in , a rechargeable battery 1000 according to one or more embodiments includes an electrode assembly 10 , a case 27 accommodating the electrode assembly 10 , and a cap assembly 30 installed in an opening of the case 27 .

[0044] The electrode assembly 10 includes a positive electrode 11 and a negative electrode 12 which are sequentially stacked (eg, stacked or wound together) and a separator 13 therebetween. The separator 13 is placed between the positive electrode 11 and the negative electrode 12 to insulate them from each other.

[0045] By placing the separator 13 between the positive electrode (or first electrode) 11 and the negative electrode (or second electrode) 12, winding them around a winding axis X, and then pressing them to be flat (substantially flat), the electrode assembly 10 may be a core type or core-like.

[0046] The separator 13 may be a polymer film that allows lithium ions to pass therethrough, and may be made of polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer of two or more layers thereof, as well as a mixed multilayer (such as a polyethylene / polypropylene double-layer separator, a polyethylene / polypropylene / polyethylene three-layer separator, and / or a polypropylene / polyethylene / polypropylene three-layer separator, etc.).

[0047] The positive electrode 11 may be Figure 1 The positive electrode shown in FIG. 1 includes an electrode active area DA1 and an electrode passivation area DA2. The electrode active area DA1 includes a substrate formed of a thin sheet metal foil and a positive electrode active material layer made of a positive electrode active material on the substrate. The electrode passivation area DA2 is an area where the substrate is exposed because the positive electrode active material layer is not formed on the substrate, and may be a portion extending from the substrate of the electrode active area.

[0048] The electrode passivation area DA2 of the positive electrode may be located at one end of the positive electrode 11 along the length of the positive electrode 11 .

[0049] The substrate of the positive electrode 11 may be aluminum, and as the positive electrode active material, a compound capable of reversibly inserting and extracting lithium ions (lithiated inserting compound) may be used. For example, one or more types (kinds) of composite oxides of metals of cobalt, manganese, nickel and / or a combination thereof (e.g., selected from cobalt, manganese, nickel and / or a combination thereof) and lithium may be used. In the positive electrode, the content (e.g., amount) of the positive electrode active material may be 90 weight percent (wt%) to 98 wt% relative to the total weight of the positive electrode active material layer.

[0050] In one or more embodiments, the positive active material may further include a binder and a conductive material. In one or more embodiments, the binder and the conductive material may be contained in an amount (eg, in an amount) of 1 wt % to 5 wt % relative to the total weight of the positive active material layer.

[0051] The binder is used to adhere the positive active material particles to each other and also to adhere the positive active material to the positive electrode substrate. Representative examples of the binder may include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers including ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, and nylon, but the present disclosure is not limited thereto.

[0052] The conductive material is used to provide conductivity to the electrode, and in the constructed battery, any material can be used as the conductive material as long as it does not cause chemical changes.

[0053] The negative electrode 12 includes an electrode active region DB1 and an electrode passivation region DB2, and the electrode active region DB1 includes a substrate formed of a thin metal foil and a negative electrode active material layer made of a negative electrode active material on the substrate (or in an intermediate layer). The electrode passivation region is a region where the substrate is exposed because the negative electrode active material layer is not formed, and may be a portion extending from the substrate of the electrode active region.

[0054] The electrode passivation region DB2 of the negative electrode may be positioned at one end of the negative electrode 12 along the length direction of the negative electrode 12. In one or more embodiments, the electrode passivation region DA2 of the positive electrode 11 and the electrode passivation region DB2 of the negative electrode may be positioned on opposite sides relative to the electrode active regions DA1 and DB1, respectively.

[0055] Of course, the electrode passivation regions of the positive electrode and the negative electrode may protrude from the substrate at regular intervals along the winding direction, or may be positioned at the tip or end of the wound electrode assembly.

[0056] The substrate of the negative electrode 12 may be a material selected from the group consisting of (e.g., consisting of) copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive material, and / or any suitable combination thereof.

[0057] The negative electrode active material included in the negative electrode active material layer may be a carbon-based active material. The carbon-based negative electrode active material may be artificial graphite or a mixture of artificial graphite and natural graphite. If the negative electrode active material is a crystalline carbon-based material obtained by mixing natural graphite with artificial graphite, the crystalline carbon-based material may have a more developed crystallization characteristic than the amorphous carbon-based active material (for example, when the negative electrode active material is a crystalline carbon-based material obtained by mixing natural graphite with artificial graphite, the crystalline carbon-based material may have a more developed crystallization characteristic than the amorphous carbon-based active material), thereby further improving the orientation characteristics of the carbon material in the electrode plate with an external magnetic field. Artificial graphite or natural graphite may be indefinite, plate-like, flaky, spherical, fibrous and / or any suitable combination thereof, without particular limitation. In addition, if a mixture of artificial graphite and natural graphite is used, the mixing ratio (in terms of weight % of artificial graphite:natural graphite) may be 70:30 (wt %) to 95:5 (wt %) (e.g., when a mixture of artificial graphite and natural graphite is used, the mixing ratio (in terms of weight % of artificial graphite:natural graphite) may be 70:30 (wt %) to 95:5 (wt %)).

[0058] In one or more embodiments, the negative electrode active material layer may include a Si-based negative electrode active material, a Sn-based negative electrode active material, and LiMO x At least one of the negative electrode active materials (M=metal). If the negative electrode active material layer further includes a carbon-based negative electrode active material as the first negative electrode active material and the above-mentioned negative electrode active material as the second negative electrode active material, the mixing ratio of the first negative electrode active material and the second negative electrode active material (in terms of weight % of the first negative electrode active material: the second negative electrode active material) may be 50:50 (wt%) to 99:1 (wt%) (for example, when the negative electrode active material layer further includes a carbon-based negative electrode active material as the first negative electrode active material and the above-mentioned negative electrode active material as the second negative electrode active material, the mixing ratio of the first negative electrode active material and the second negative electrode active material (in terms of weight % of the first negative electrode active material: the second negative electrode active material) may be 50:50 (wt%) to 99:1 (wt%)).

[0059] LiMO x The negative electrode active material (M = metal) can be lithium vanadium oxide.

[0060] Si-based negative electrode active materials can be Si, Si-C composites, SiO x(0 < x < 2) or an Si-Q alloy (Q is an element in a group (e.g., consisting of, e.g., selected from) including the following: alkali metals, alkaline earth metals, Group 13 elements, Group 14 elements, Group 15 elements, Group 16 elements, transition metals, rare earth elements, and / or any suitable combination thereof), the Sn-based negative electrode active material may include Sn, SnO 2 and / or an Sn-R alloy (R is an element in a group (e.g., consisting of, e.g., selected from) including the following: alkali metals, alkaline earth metals, Group 13 elements, Group 14 elements, Group 15 elements, Group 16 elements, transition metals, and / or rare earth elements, but not including Sn), and at least one of them may be mixed with SnO 2 The element Q and the element R may be at least one element in a group (e.g., consisting of, e.g., selected from) including the following: Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Pb, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Tl, Ge, P, As, Sb, Bi, S, Se, Te, Po, and / or any suitable combination thereof. In the present disclosure, expressions such as "not including 'component' or any 'component'", "excluding 'component' or any 'component'", and / or "not containing 'component'" mean that the said "component" is not added, selected, or used as a component in the composition, but may still include less than a suitable amount of the said "component" due to other impurities and / or external factors.

[0061] Based on the total weight of the negative electrode active material layer, the content (e.g., amount) of the negative electrode active material in the negative electrode active material layer may be 95 wt% to 99 wt%.

[0062] The negative electrode active material includes a binder and may optionally further include a conductive material. Based on the total weight of the negative electrode active material, the content (e.g., amount) of the binder in the negative electrode active material may be 1 wt% to 5 wt%. In one or more embodiments, if a conductive material is further included, the negative electrode active material may be used in an amount of 90 wt% to 98 wt%, the binder may be used in an amount of 1 wt% to 5 wt%, and the conductive material may be used in an amount of 1 wt% to 5 wt% (e.g., when a conductive material is further included, the negative electrode active material may be used in an amount of 90 wt% to 98 wt%, the binder may be used in an amount of 1 wt% to 5 wt%, and the conductive material may be used in an amount of 1 wt% to 5 wt%).

[0063] The binder is used to adhere the negative active material particles to each other and also to adhere the negative active material to the negative electrode base substrate. As the binder, a non-aqueous binder, an aqueous binder and / or any suitable combination thereof may be used.

[0064] Examples of non-aqueous binders may include polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers including ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide-imide, polyimide, and / or any suitable combination thereof.

[0065] Examples of aqueous adhesives may include styrene-butadiene rubber, acrylated styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber, acrylic rubber, butyl rubber, ethylene-propylene copolymer, polyepichlorohydrin, polyphosphazene, polyvinyl pyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, acrylate resin and / or any suitable combination thereof.

[0066] If an aqueous binder is used as a negative electrode binder, a cellulose compound capable of imparting viscosity may be further included as a thickener (for example, when an aqueous binder is used as a negative electrode binder, a cellulose compound capable of imparting viscosity may be further included as a thickener). As a cellulose compound, carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose and / or an alkali metal salt thereof may be used in combination. As an alkali metal, Na, K or Li may be used. The content (for example, amount) of the thickener may be 0.1 to 3 parts by weight based on 100 parts by weight of the negative electrode active material.

[0067] The conductive material is used to impart conductivity to the electrode, and any electronic conductive material that does not cause chemical changes in the battery can be used. Examples of the conductive material may include: carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, and carbon fiber; metal powders such as copper, nickel, aluminum, and silver; metal-based materials such as metal fibers; conductive polymers such as polyphenylene derivatives; and conductive materials containing (including) any suitable mixture thereof.

[0068] The BET specific surface area of ​​the negative electrode active material layer can be less than 3.0 m 2 / g, and can be 2 / g to 1m 2 / g. If the BET specific surface area of ​​the negative electrode active material layer is less than 3.0 m 2 / g, the electrochemical life characteristics of the battery cell can be improved (for example, when the BET specific surface area of ​​the negative electrode active material layer is less than 3.0 m 2 / g, the electrochemical life characteristics of the battery cell can be improved).

[0069] The BET measurement is performed by charging / discharging a lithium rechargeable battery including a negative electrode, cutting the negative electrode obtained by rupturing the battery in a fully discharged state into a set or predetermined size, then placing the cut negative electrode in a BET sample holder, and measuring it by a nitrogen adsorption method.

[0070] The negative electrode may have 6 mg / cm 2 Up to 65mg / cm 2 Cross-section loading level (L / L).

[0071] In one or more embodiments, the electrode assembly 10 may be accommodated in the case 27 together with an electrolyte, and the electrolyte may include a non-aqueous organic solvent and a lithium salt.

[0072] The nonaqueous organic solvent serves as a medium through which ions participating in the electrochemical reaction of the battery can move.

[0073] Lithium salts are dissolved in organic solvents and used as a supply source of lithium ions in batteries, enable basic lithium secondary battery operations, and are materials that promote the movement of lithium ions between positive electrodes and negative electrodes. Representative examples of such lithium salts include one or two or more of the following groups (e.g., consisting of the following) as supporting electrolyte salts (e.g., one or two or more selected from the following as supporting electrolyte salts): LiPF 6 , LiBF 4 、LiSbF 6 、LiAsF 6 、LiN(SO 2 C 2 F 5 ) 2 、Li(CF 3 SO 2 ) 2 N、LiN(SO 3 C 2 F 5 ) 2 ,LiC 4 F 9 SO 3 、LiClO 4 、LiAlO 2 、LiAlCl 4 、LiN((C x F 2x+1 SO 2 )、(C y F 2y+1 SO 2) (wherein x and y are natural numbers, such as integers from 1 to 20)), LiCl, LiI and / or LiB(C 2 O 4 ) 2 (Lithium bis(oxalato)borate: LiBOB). It is recommended to use a lithium salt concentration in the range of 0.1M to 2.0M. If the concentration of the lithium salt is within this range, the electrolyte has appropriate or suitable conductivity and viscosity (e.g., when the concentration of the lithium salt is within this range, the electrolyte has appropriate or suitable conductivity and viscosity), so it can exhibit excellent or suitable electrolyte performance, and lithium ions can move efficiently.

[0074] The housing 27 may be made of metal such as aluminum and may have a substantially cubic shape. One side of the housing 27 may be open, and a cover plate may be mounted on the open side of the housing 27.

[0075] The cap assembly 30 includes a cap plate 31 coupled to the case 27 and blocking an opening of the case 27 , a positive terminal 21 protruding to the outside of the cap plate 31 and electrically connected to the positive electrode 11 , and a negative terminal 22 electrically connected to the negative electrode 12 .

[0076] The cover plate 31 is in the form of an elongated plate connected in one direction, and is connected to the opening of the housing 27 .

[0077] The cover plate 31 has an injection port 32 penetrating into the interior of the housing 27. The injection port 32 is used to inject an electrolyte solution, and a sealing plug 38 may be installed. In one or more embodiments, a vent plate 39 having a notch 39a formed thereon is installed in the vent hole 34 so that the cover plate 31 can be opened at a set or predetermined pressure.

[0078] The positive terminal 21 and the negative terminal 22 are installed to protrude to (onto) the top of the cap plate 31 . The positive terminal 21 is electrically connected to the positive electrode 11 through the current collecting tab 41 , and the negative terminal 22 is electrically connected to the negative electrode 12 through the current collecting tab 42 .

[0079] The terminal connection member 25 electrically connecting the positive terminal 21 and the current collecting tab 41 is installed between the positive terminal 21 and the current collecting tab 41. The terminal connection member 25 is inserted into a hole formed in the positive terminal 21 and welded to the positive terminal 21 at the upper end and the current collecting tab 41 at the lower end.

[0080] A gasket 59 for sealing is installed between the terminal connection member 25 and the cap plate 31 by being inserted into the hole through which the terminal connection member 25 passes, and a lower insulating member 43 into which the lower portion of the terminal connection member 25 is inserted is installed below the cap plate 31. A connecting plate 58 is installed between the positive terminal 21 and the cap plate 31 to electrically connect them. The terminal connection member 25 is inserted and installed into the connecting plate 58. Therefore, the cap plate 31 and the case 27 are charged with the positive electrode 11.

[0081] A terminal connection member 26 electrically connecting the negative terminal 22 and the current collecting tab 42 is installed between the negative terminal 22 and the current collecting tab 42. The terminal connection member 26 is inserted into a hole formed in the negative terminal 22 and welded to the negative terminal 22 at an upper end and to the current collecting tab 42 at a lower end.

[0082] A gasket 59 for sealing is installed between the negative terminal 22 and the cap plate 31 by being inserted into a hole through which the terminal connection member 26 passes, and an upper insulating member 54 is installed for insulating between the negative terminal 22 and the cap plate 31. The terminal connection member 26 may be installed by being inserted into a hole of the upper insulating member 54, and the upper insulating member 54 may be formed to surround an end of the negative terminal 22.

[0083] Below the cap plate 31 , a lower insulating member 45 is installed for insulating the negative terminal 22 and the current collecting tab 42 from the cap plate 31 .

[0084] The short-circuit hole 37 is formed in the cap plate 31, and the short-circuit member 56 is installed in the short-circuit hole 37. The short-circuit member 56 includes a bent portion convexly bent downward in an arc shape and an edge portion formed on the outer side of the bent portion and fixed to the cap plate 31. The upper insulating member 54 may have a cutout overlapping the short-circuit hole 37, and the short-circuit member 56 overlaps the negative terminal 22 exposed through the cutout.

[0085] The short-circuit member 56 is electrically connected to the cap plate 31, and if the internal pressure of the rechargeable battery 1000 rises, the short-circuit member 56 is deformed (e.g., when the internal pressure of the rechargeable battery 1000 rises, the short-circuit member 56 is deformed), thereby causing a short circuit between the positive electrode and the negative electrode. For example, if gas is generated inside the rechargeable battery due to an abnormal reaction, the internal pressure of the rechargeable battery increases (e.g., when gas is generated inside the rechargeable battery due to an abnormal reaction, the internal pressure of the rechargeable battery increases). If the internal pressure of the rechargeable battery exceeds a set pressure or a predetermined pressure, the curved portion is transformed into a convex shape in an upward direction (e.g., when the internal pressure of the rechargeable battery exceeds a set pressure or a predetermined pressure, the curved portion is transformed into a convex shape in an upward direction), and the negative terminal 22 contacts the short-circuit member 56 to cause a short circuit.

[0086] To facilitate short circuiting of the negative terminal 22 and the short circuit member 56 , the negative terminal 22 may further include one or more protrusions protruding toward the short circuit member 56 , and the protrusions may be separated from the short circuit member 56 .

[0087] Figure 6 is a schematic exploded perspective view of a rechargeable battery according to one or more embodiments of the present disclosure.

[0088] like Figure 6 As shown in , a rechargeable battery 1001 according to one or more embodiments includes an electrode assembly 101 and a pouch 29 .

[0089] The electrode assembly 101 may include a positive electrode and a negative electrode and a separator between the positive electrode and the negative electrode. The electrode assembly 101 may be in the form of a core wound around a winding axis X.

[0090] The positive electrode can be Figure 1 The positive electrode shown in , and may include a substrate and a positive electrode active material layer formed on the substrate, the positive electrode active material layer having a pore ratio of 11 volume % to 16 volume % and an average particle size D50 in the positive electrode active material layer of 8 μm to 20 μm.

[0091] The first electrode tab 14 and the second electrode tab 23 may be connected to an electrode passivation region of the positive electrode and an electrode passivation region of the negative electrode, respectively.

[0092] The electrode assembly 101 may be contained in a bag-type or pouch-like case together with an electrolyte. The bag-type or pouch-like case may be formed by laminating an outer portion, and the outer portion may include a lower outer portion and an upper outer portion, and the electrode assembly 101 is placed between them and then sealed by heat fusion.

[0093] The laminated outer layer may be formed into a multi-layer structure having, for example, a first insulating layer 2, a metal layer 3, and a second insulating layer 4. Of course, one or more suitable other adhesive layers or functional layers may be added.

[0094] The first insulating layer 2 is formed of a material that is insulating and heat-bondable to the inner surface of the laminated outer portion, and can be sealed by heat-melting the edges in a state where the electrode assembly 101 is accommodated in the bag. In addition, the first insulating layer 2 is formed on one surface of the metal layer 3 and forms the inner surface of the laminated outer portion facing the electrode assembly 101. The first insulating layer 2 may be formed of cast polypropylene (CPP) and / or its equivalent that does not react with the electrolyte solution.

[0095] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It will also be understood that terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or in this specification, and should not be interpreted in an idealized or overly formal sense, unless explicitly defined as such herein.

[0096] As used herein, the terms "substantially," "approximately," and similar terms are used as terms of approximation rather than terms of degree, and are intended to account for the inherent deviations in measured or calculated values ​​that one of ordinary skill in the art would recognize. As used herein, "substantially" includes the stated value and means within an acceptable range of deviation for a particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "substantially" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the stated value.

[0097] In addition, any numerical range described herein is intended to include all sub-ranges of the same numerical precision contained in the described range. For example, the range of "1.0 to 10.0" is intended to include all sub-ranges between the described minimum value 1.0 and the described maximum value 10.0 (and including the described minimum value 1.0 and the described maximum value 10.0), that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit described herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit described in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification (including claims) to explicitly describe any sub-range contained in the range explicitly described here.

[0098] Additionally, the use of “may” when describing embodiments of the present disclosure refers to “one or more embodiments of the present disclosure.”

[0099] As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0100] The portable device, vehicle and / or battery (e.g., battery controller) and / or any other related device or component according to the embodiments of the present disclosure described herein may be implemented using any suitable hardware, firmware (e.g., application specific integrated circuit), software, or a combination of software, firmware, and hardware. For example, the various components of the device may be formed on an integrated circuit (IC) chip or on separate IC chips. In addition, the various components of the device may be implemented on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or formed on a substrate. In addition, the various components of the device may be processes or threads that run on one or more processors in one or more computing devices, execute computer program instructions, and interact with other system components to perform the various functions described herein. The computer program instructions are stored in a memory, which may be implemented in a computing device using a standard memory device such as a random access memory (RAM) as an example. The computer program instructions may also be stored in other non-transitory computer-readable media such as CD-ROMs, flash drives, etc. as examples. In addition, those skilled in the art should recognize that, without departing from the scope of the embodiments of the present disclosure, the functions of various computing devices may be combined or integrated into a single computing device, or the functions of a particular computing device may be distributed throughout one or more other computing devices.

[0101] Although embodiments of the present disclosure have been described, it is understood that the present disclosure should not be limited to these embodiments, but one or more suitable variations and modifications may be made by one of ordinary skill in the art within the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

[0102] Reference numerals 10.101: Electrode assembly 11, 70: Positive electrode 12: Negative electrode 13: Diaphragm 21: Positive terminal 14, 23: Electrode terminal block 22: Negative terminal 41, 42: Collecting lugs 27: Shell 30: Cover assembly 71: Base 72: Positive electrode active material layer 29: bag 1000, 1001: Rechargeable battery.

Claims

1. A positive electrode, comprising: substrate; as well as a positive electrode active material layer on at least one surface of the substrate and comprising particles, The positive electrode active material layer has a pore ratio of 11 volume % to 16 volume %, an average particle size D50 of 8 μm to 20 μm, and Wherein, the positive electrode is used in a battery.

2. The positive electrode according to claim 1, wherein The loading level of the positive electrode active material layer is 40 mg / cm 2 Up to 60mg / cm 2 .

3. The positive electrode according to claim 1, wherein: The positive electrode active material layer includes first pores and second pores of different sizes, and The diameter of the first hole is 0.2 μm to 0.5 μm.

4. The positive electrode according to claim 3, wherein The first pores account for 55 volume % to 65 volume % of the entire pore volume of the positive electrode active material layer.

5. The positive electrode according to claim 1, wherein The compression ratio of the positive electrode active material layer is 69 volume % to 73 volume %.

6. The positive electrode according to claim 1, wherein The substrate includes aluminum.

7. A battery comprising the positive electrode according to claim 1.

8. A rechargeable battery, comprising: An electrode assembly comprising the positive electrode according to claim 1; A shell, accommodating the electrode assembly; an electrolyte in the housing; as well as A cover assembly is coupled to the housing and seals the housing.

9. The rechargeable battery according to claim 8, wherein: The housing is bag-shaped.

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