DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after allowance or after an Office action under Ex Parte Quayle, 25 USPQ 74, 453 O.G. 213 (Comm'r Pat. 1935). Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant's submission filed on 4/3/26 has been entered.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 4/3/26 was filed. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement has been considered by the examiner.
Response to Amendment
In the amendment dated 11/5/2025, the following has occurred: Claims 1, 3, 26 have been amended; Claim 5 is cancelled; and new Claim 28 has been added.
Claims 1-4 and 6-28 are pending. Claims 1-4, 5-12, and 22-28 are examined in this office action. This communication is a Non-Final Rejection in response to the "Amendment" and "Remarks" filed on 11/5/25.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 8 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
In Claim 8, the limitation "M1 is at least one of Co, Mn, of Al" is indefinite because the use of the preposition "of" instead of the disjunctive conjunction "or" creates an ambiguous Markush group. It is unclear whether "Al" (aluminum) is intended to be a functional alternative within the group of metals (e.g., "at least one of Co, Mn, or Al") or if the term "of Al" is meant to qualify the preceding elements in a manner not described in the specification.
The specification explicitly describes M1 as being "at least one of... a cobalt precursor, a manganese precursor, or an aluminum precursor" and further defines M1 in Formula 1 as "at least one of... Co, Mn, or Al". Consequently, the claim language "of Al" does not correspond to the disclosed alternatives and leaves the boundaries of the claim subject to multiple interpretations.
Claim Rejections - 35 USC § 103
Claims 1, 2, 7, and 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2012/137391 A1 (WO’391).
As to Claim 1: WO’391 discloses a cathode active material for lithium secondary batteries (Abstract; WO’391, p. 1; p. 2); nickel-based lithium metal oxide secondary particles each comprising a plurality of large primary particles (WO’391 teaches secondary particles formed by aggregating a plurality of single-crystal primary particles of a lithium composite oxide such as Li(Ni₀.₈Co₀.₁₅Al₀.₀₅)O₂; WO’391, pp. 3-4, 7, 13-14); the nickel-based lithium metal oxide secondary particles having a structure having pores therein (WO’391 teaches secondary particles having a large number of pores V with a porosity of 3% to 30% and an average pore size of 0.1 μm to 5 μm; WO’391, pp. 4, 6-7, 17); the plurality of large primary particles having a size (WO’391 teaches primary particles having an average particle diameter of 0.01 μm or more and 5 μm or less; WO’391, pp. 1, 3-5, 17); the nickel-based lithium metal oxide secondary particles having a size (WO’391 teaches secondary particles having an average diameter of 1 μm or more and 100 μm or less; WO’391, pp. 1, 3, 6, 17); and a cobalt compound-containing coating layer on surfaces of the nickel-based lithium metal oxide secondary particles, wherein the cobalt compound-containing coating layer comprises a cobalt compound, and wherein the cobalt compound is a lithium cobalt oxide (WO’391 teaches the surface of the single-crystal primary particles or the positive electrode active material particles 222 may be coated with lithium cobaltate, which is a lithium cobalt oxide; WO’391, p. 16).
However, WO’391 does not explicitly recite that the secondary particles have a “hollow structure” (it uses the term “large number of pores”), nor does it explicitly recite the specific sub-ranges of about 2 μm to about 6 μm for primary particles or about 10 μm to about 18 μm for secondary particles.
The disclosure of WO’391 renders these limitations obvious. WO’391 acknowledges that hollow structures were known in the art for improving battery characteristics (WO’391 discusses prior positive electrode active materials in which pores/voids are formed therein; WO’391, p. 2). Furthermore, the claimed primary particle size range of 2-6 μm and secondary particle size range of 10-18 μm significantly overlap with the broader preferred ranges taught by WO’391, namely 0.01-5 μm for primary particles and 1-100 μm for secondary particles. WO’391 teaches that optimizing particle diameters within these ranges ensures the filling property is improved and that output and rate characteristics are maintained (WO’391, pp. 5-6). One of ordinary skill in the art would recognize that selecting specific sub-ranges within the broad disclosures of WO’391 is a matter of routine optimization to achieve desired electrode performance and packing density.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the specific particle size of the primary and secondary particles within the broad ranges disclosed in WO’391, and to employ a hollow morphology as known in the art, to improve the filling property of the positive electrode active material and the overall electrochemical performance of the resulting battery.
As to Claim 2:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based secondary particles formed of a plurality of primary particles with internal pores, particle sizes encompassing the claimed ranges, and a lithium cobalt oxide coating; WO’391, pp. 1, 3-7, 13-14, 16-17); and wherein at least one of the surfaces of the plurality of large primary particles comprises the cobalt compound-containing coating layer (WO’391 teaches that the “surface of the single-crystal primary particles 222a... may be coated with another material” such as “lithium cobaltate,” which is a lithium cobalt oxide; WO’391, p. 16).
However, WO’391 does not explicitly describe the coating as being present on the “grain boundaries” of the primary particles in the specific context of the coating application step.
The disclosure of WO’391 renders this limitation obvious because WO’391 teaches that the secondary particles are formed by the aggregation of single-crystal primary particles and identifies the interfaces between these adjacent primary particles as “grain boundaries” (WO’391, pp. 3-5). Furthermore, WO’391 explicitly suggests coating the individual single-crystal primary particles to improve chemical stability and rate characteristics (WO’391, p. 16). A person of ordinary skill in the art would recognize that applying a coating to primary particles which are then aggregated into a secondary particle would inherently and predictably result in the coating material being disposed at the grain boundaries between the adjacent primary particles within the resulting secondary particle structure.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to provide the cobalt compound-containing coating on the surfaces and thus the grain boundaries of the primary particles by coating the individual primary particles prior to or during aggregation into secondary particles, as suggested by the teachings of WO’391, in order to minimize grain boundary resistance and enhance lithium ion diffusivity throughout the secondary particle. WO’391 teaches that grain boundary resistance affects lithium-ion diffusion and electron conduction, and that reducing grain boundary resistance improves lithium-ion diffusivity, electron conductivity, and charge/discharge characteristics. WO’391, pp. 4-5.
As to Claim 7:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based lithium metal oxide secondary particles formed of single-crystal primary particles, having internal pores, particle sizes encompassing the claimed ranges, and a cobalt-based coating; WO’391, pp. 1, 3-7, 13-14, 16-17); and wherein the pores in the cathode active material have a size (WO’391 teaches that the secondary particles have a structure with a large number of internal pores V and explicitly discloses that “the average pore diameter is 0.1 μm or more and 5 μm or less”; WO’391, pp. 4, 6-7, 17).
However, WO’391 does not explicitly recite the specific numerical sub-range of about 2 μm to about 7 μm for the pore size.
The disclosure of WO’391 renders this limitation obvious. WO’391 teaches that the presence of pores V in the secondary particles is a critical feature that improves the rate characteristics of the battery by allowing the electrolyte to effectively enter the interior of the particle. WO’391 teaches that the pores V, together with reduced grain boundary resistance, improve lithium ion diffusibility and electron conductivity in the positive electrode active material particles, and thereby improve charge/discharge characteristics (WO’391, pp. 4-5). The claimed range of 2 μm to 7 μm overlaps with the broader range of 0.1 μm to 5 μm explicitly taught by WO’391. WO’391 further teaches that if the average pore diameter exceeds 5 μm, relatively large pores are generated, which reduces the amount per volume of positive electrode active material contributing to charge/discharge and causes stress concentration, while if the average pore diameter is less than 0.1 μm, it becomes difficult to contain conductive material and electrolyte and the stress-releasing effect becomes insufficient (WO’391, pp. 6-7). A person of ordinary skill in the art would recognize that the specific diameter of these internal pores is a result-effective variable that can be tailored to optimize the balance between the reactive surface area available to the electrolyte and the mechanical strength or filling density of the active material. Selecting an overlapping sub-range for a known parameter is generally a matter of routine optimization in the art.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the size of the pores within the claimed range of about 2 μm to about 7 μm to maximize the access of the electrolyte into the secondary particles while maintaining sufficient structural integrity, as motivated by the teaching in WO’391 to improve rate characteristics through the optimization of pore formation.
As to Claim 11:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based lithium metal oxide secondary particles formed of single-crystal primary particles, having internal pores, specific particle sizes, and a lithium cobalt oxide coating; WO’391, pp. 1, 3-7, 13-14, 16-17); and a peak intensity ratio and area ratio of the cathode active material measured by X-ray diffraction analysis (WO’391 teaches that the cathode active material has a layered rock salt structure and focuses extensively on the orientation of the (003) plane relative to other planes, such as the (104) plane, to facilitate the entry and exit of lithium ions; WO’391, pp. 2-5). Specifically, WO’391 teaches controlling the manufacturing process to ensure the orientation ratio of the (003) plane is 60% or more, and more preferably 75% or 90% (WO’391, pp. 3-5, 10-12, 17).
However, WO’391 does not explicitly recite the specific numerical values for the peak intensity ratio I(003)/I(104) of about 1.2 to about 4.0 or the area ratio A(003)/A(104) of about 1.1 to about 1.4.
The disclosure of WO’391 renders these limitations obvious. WO’391 teaches that the (003) plane orientation is the critical parameter for achieving high conductivity and superior rate characteristics in lithium secondary batteries (WO’391, pp. 3-5). In the field of X-ray diffraction (XRD) analysis for layered lithium metal oxides, the intensity and area ratios of the (003) peak to the (104) peak are the standard industry metrics used to quantify the degree of cation ordering and the specific crystallographic orientation taught by the reference. A person of ordinary skill in the art would recognize that achieving a high (003) orientation ratio of 60% to 90%—as explicitly directed by WO’391—would inherently and predictably result in I(003)/I(104) and A(003)/A(104) ratios within the claimed ranges, as the (003) peak becomes mathematically more dominant as the degree of orientation increases.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the XRD intensity and area ratios within the claimed ranges by following the orientation-controlled manufacturing process taught in WO’391, in order to verify that the target (003) orientation had been reached and to ensure high lithium-ion diffusivity throughout the cathode active material.
As to Claim 12:
WO’391 discloses a cathode active material for lithium secondary batteries (Title; Abstract; WO’391, p. 1); nickel-based lithium metal oxide secondary particles each comprising a plurality of large primary particles (WO’391 teaches secondary particles formed by aggregating a plurality of single-crystal primary particles of a lithium composite oxide such as Li(Ni₀.₈Co₀.₁₅Al₀.₀₅)O₂; WO’391, pp. 3-4, 7, 13-14); the nickel-based lithium metal oxide secondary particles having a hollow structure having pores therein (WO’391 teaches secondary particles having a large number of internal pores V with a porosity of 3% to 30%; WO’391, pp. 4, 6-7, 17); the plurality of large primary particles having a size of about 2 μm to about 6 μm (WO’391 teaches single-crystal primary particles having an average particle diameter of 0.01 μm or more and 5 μm or less, which overlaps with the claimed range; WO’391, pp. 1, 3-5, 17); and the nickel-based lithium metal oxide secondary particles having a size of about 10 μm to about 18 μm (WO’391 teaches secondary particles with an average diameter of 1 μm or more and 100 μm or less, which encompasses the claimed range; WO’391, pp. 1, 3, 6, 17); and a cobalt compound-containing coating layer on surfaces of the nickel-based lithium metal oxide secondary particles, wherein the cobalt compound-containing coating layer comprises a cobalt compound, and wherein the cobalt compound is a lithium cobalt oxide (WO’391 teaches the surface of the single-crystal primary particles or the positive electrode active material particles 222 may be coated with lithium cobaltate, which is a lithium cobalt oxide; WO’391, p. 16).
However, WO’391 does not explicitly recite that the secondary particles comprise a large primary particle layer having a “single layer or two-layer structure.”
The disclosure of WO’391 renders this limitation obvious. WO’391 teaches that the secondary particles are formed by the aggregation of single-crystal primary particles and possess a structure with internal pores V (WO’391, pp. 3-4). WO’391 further describes a modified embodiment where the orientation of the “surface layer portion” of the secondary particle is distinct from the orientation of the interior (WO’391, p. 16). A person of ordinary skill in the art would recognize that a hollow or porous aggregate of primary particles inherently possesses a shell or “layer” of those primary particles. Designing the thickness of this shell to consist of a single layer or two layers of primary particles is a matter of routine optimization in the manufacturing of hollow particles to balance the structural integrity of the secondary particle against the need for rapid lithium-ion diffusion to the interior.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to configure the aggregated primary particles of the hollow secondary particle into a single-layer or two-layer shell structure, as motivated by the teachings of WO’391, in order to maximize the surface area accessible to the electrolyte while maintaining the overall mechanical strength of the secondary particle.
Claims 6 and 28 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2012/137391 A1 (WO’391), as applied to Claim 1 above, and further in view of WO 2021/045025 A1 (WO’025).
As to Claim 6:
WO’391 discloses a cathode active material for lithium secondary batteries (WO’391, Title; Abstract; pp. 1-2); nickel-based lithium metal oxide secondary particles each comprising a plurality of large primary particles (WO’391 teaches secondary particles formed by aggregating a plurality of single-crystal primary particles of a lithium composite oxide such as Li(Ni₀.₈Co₀.₁₅Al₀.₀₅)O₂; WO’391, pp. 3-4, 7, 13-14); the nickel-based lithium metal oxide secondary particles having a structure having pores therein (WO’391 teaches secondary particles having a large number of pores V with a porosity of 3% to 30% and an average pore size of 0.1 μm to 5 μm; WO’391, pp. 4, 6-7, 17); the plurality of large primary particles having a size (WO’391 teaches an average particle diameter of 0.01 μm or more and 5 μm or less, which overlaps with the claimed range of about 2 μm to about 6 μm; WO’391, pp. 1, 3-5, 17), and the nickel-based lithium metal oxide secondary particles having a size (WO’391 teaches an average particle size of 1 μm or more and 100 μm or less, which encompasses the claimed range of about 10 μm to about 18 μm; WO’391, pp. 1, 3, 6, 17); and a cobalt compound-containing coating layer on surfaces of the nickel-based lithium metal oxide secondary particles, wherein the cobalt compound-containing coating layer comprises a cobalt compound, and wherein the cobalt compound is a lithium cobalt oxide (WO’391 teaches that the “surface of the single-crystal primary particles 222a or the positive electrode active material particles 222 may be coated with another material” such as “lithium cobaltate”; WO’391, p. 16).
However, WO’391 does not explicitly disclose that the cobalt compound-containing coating layer further comprises at least one of boron, manganese, phosphorus, aluminum, zinc, zirconium, or titanium.
WO’025 teaches a positive electrode active material for lithium ion secondary batteries containing a lithium transition metal composite oxide that can include manganese (Mn) or aluminum (Al) as an “M” element, and titanium (Ti), zirconium (Zr), or zinc (Zn) as an “X” element (WO’025, pp. 2-6, 24-25). WO’025 further teaches that the material may include “other components that coat particles” and specifically discloses that these coating components may contain a boron component or a phosphorus component (WO’025, p. 3). Additionally, WO’025 teaches that the “X” element, e.g., Ti, Zr, Zn, tends to form a concentrated layer on the surface of the primary particles, and that Ti has a strong bond with O and stabilizes the crystal structure (WO’025, pp. 5-6).
WO’391 and WO’025 are analogous arts because both are directed to the same field of endeavor, specifically positive electrode active materials for lithium secondary batteries, and both address the common technical problem of improving electrochemical performance, such as discharge capacity and cycle stability. WO’391 teaches improving charge/discharge characteristics through primary-particle/secondary-particle structure, pores, and surface coating (WO’391, pp. 4-7, 16), while WO’025 teaches high discharge capacity and good charge/discharge cycle characteristics for nickel-based lithium transition metal composite oxide positive electrode active materials (WO’025, pp. 2-6, 23-24).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to further include at least one of boron, manganese, phosphorus, aluminum, zinc, zirconium, or titanium in the cobalt compound-containing coating layer of the cathode active material taught by WO’391, because WO’025 teaches that these specific elements are effective surface modification and coating components for stabilizing high-nickel cathode active materials. One of ordinary skill in the art would have been motivated to incorporate these additional dopants into the existing coating layer of WO’391 to further stabilize the crystal structure and suppress side reactions with the electrolyte, thereby enhancing the capacity retention and life characteristics of the resulting battery.
As to Claim 28:WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based secondary particles formed of aggregated primary particles with internal pores and a lithium cobaltate coating; WO’391, pp. 1, 3-7, 13-14, 16-17); and wherein after formation of the cobalt compound-containing coating layer, a peak intensity ratio, an area ratio, and a full-width at half-maximum (FWHM) ratio of the cathode active material are measured by X-ray diffraction (XRD) (WO’391 teaches electron backscatter diffraction (EBSD) analysis to measure the crystallographic orientation and properties of the secondary particles, specifically focusing on the relationship between the (003) plane and other planes such as the (104) plane; WO’391, pp. 2-5, 11-13).
However, WO’391 does not explicitly recite the specific numerical ratios of (i) I(003)/I(104) of about 1.3 to about 1.8, (ii) A(003)/A(104) of about 1.12 to about 1.38, and (iii) FWHM(003)/FWHM(104) of about 0.80 to about 0.90.
WO’025 teaches a nickel-based cathode active material and emphasizes the importance of controlling surface crystallinity to ensure high discharge capacity and cycle life. WO’025 specifically teaches measuring and optimizing the FWHM of specific vibration peaks, such as E₉ and A₁g, to verify that the crystallinity of the active material near the surface is “sufficiently high” (WO’025, pp. 7-8, 22).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the peak intensity, area, and FWHM ratios of the (003) and (104) planes within the claimed ranges, because such ratios are the crystallographic indicators of the high degree of ordering and orientation explicitly taught as critical by WO’391. A person of ordinary skill would have been motivated to utilize these specific XRD metrics as routine diagnostic tools, as suggested by the surface crystallinity control taught in WO’025, to ensure that the orientation-controlled manufacturing process of WO’391 successfully achieved the target (003) orientation rate of 75% to 90% necessary for high-performance batteries. Selecting specific numerical values for these result-effective variables is a matter of routine optimization to verify the physical properties and performance advantages taught by the prior art.
Claims 3, 4, 8, 9, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2012/137391 A1 (WO’391), as applied to Claim 1 above, and further in view of CN 105098177 B (CN’177).
As to Claim 3:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches a cathode active material for lithium secondary batteries; nickel-based lithium metal oxide secondary particles each comprising a plurality of large primary particles; the secondary particles having a structure having pores therein; the plurality of large primary particles having an average diameter of 0.01 μm to 5 μm; the secondary particles having an average diameter of 1 μm to 100 μm; and a cobalt compound-containing coating layer comprising lithium cobaltate on the surfaces of the particles; WO’391, pp. 1, 3-7, 13-14, 16-17); and wherein a content of the cobalt compound in the cobalt compound-containing coating layer is based on a total content of the cathode active material (WO’391 teaches that the surface of the active material particles may be coated with a material such as lithium cobaltate to improve rate characteristics and chemical stability; WO’391, p. 16).
However, WO’391 does not explicitly recite the specific numerical range of about 0.1 mol% to about 5.0 mol% for the cobalt compound content in the coating layer.
CN’177 teaches a nickel-based cathode material with a surface coating of a lithium-containing transition metal compound, which may include cobalt. CN’177 teaches a secondary lithium battery positive electrode material including a lithium-containing transition metal oxide main material AᵝLiₓMᵧN₁₋ᵧO₂₋α, wherein M is at least one of Ni, Co, and Mn, and the surface of the main material is formed with a lithium-containing transition metal phosphate coating layer LiₐM_bN′₁₋bPO₄₋λBζ grown in situ on the surface of the main material. CN’177 further teaches that the coating has high lithium-ion conductivity and good structural stability, suppresses oxygen release and transition-metal valence change, prevents catalytic/oxidative electrolyte decomposition, and prevents HF corrosion of the main material (CN’177, pp. 2-4). CN’177 specifically discloses that the lithium-containing transition metal phosphate coating is present in an amount of 0.01% to 30% by mass, preferably 0.1% to 5.0% by mass, based on the total mass of the positive electrode material (CN’177, p. 4). CN’177 also discloses coating-material amounts by mass relative to the active material, including 0.05 wt%, 0.10 wt%, 0.80 wt%, and 2.00 wt% in specific examples (CN’177, pp. 12, 14-16). In the context of lithium transition metal oxide coatings on lithium nickel oxides, these weight percentage values map to a molar percentage range of approximately 0.1 mol% to 2.0 mol%, which falls within and renders obvious the claimed range of about 0.1 mol% to 5.0 mol%.
WO’391 and CN’177 are analogous arts because both are directed to the same field of endeavor—cathode active materials for lithium secondary batteries—and both address the common technical challenge of improving the rate characteristics and structural stability of high-nickel active materials through surface modification and morphological optimization. WO’391 teaches improving charge/discharge characteristics through pore-containing secondary particles, oriented primary particles, and surface coating with materials such as lithium cobaltate. WO’391, pp. 4-7, 16). CN’177 teaches improving capacity, cycle performance, safety, and thermal stability through an in-situ grown surface coating on a lithium-containing transition metal oxide positive electrode material (CN’177, pp. 2-5).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the content of the cobalt compound in the coating layer of WO’391 within the claimed range of 0.1 mol% to 5.0 mol%, as suggested by the surface modification amounts taught in CN’177, because such a range represents a routine, low-level amount used in the art to effectively stabilize the particle surface against electrolyte decomposition while maintaining the high discharge capacity and energy density of the bulk active material.
As to Claim 4:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches a cathode active material for lithium secondary batteries; nickel-based lithium metal oxide secondary particles each comprising a plurality of primary particles; the secondary particles having internal pores V; the primary particles having an average diameter of 0.01 μm to 5 μm; the secondary particles having an average diameter of 1 μm to 100 μm; and a cobalt compound-containing coating layer comprising lithium cobaltate on the surfaces of the particles (WO’391, pp. 1, 3-7, 13-14, 16-17)); and wherein the cathode active material comprises a cobalt compound-containing coating layer on surfaces of the nickel-based lithium metal oxide secondary particles (WO’391 teaches that the surface of the particles may be coated with a material such as lithium cobaltate to improve rate characteristics and stability (WO’391, p. 16)).
However, WO’391 does not explicitly recite that the cobalt compound-containing coating layer has a thickness of about 1 nm to about 50 nm.
CN’177 teaches a nickel-based cathode material with a surface coating of a lithium-containing transition metal compound. CN’177 specifically discloses that the thickness of this surface coating is 20-30 nm (CN’177, p. 11). This thickness of 20-30 nm falls squarely within the claimed range of about 1 nm to about 50 nm. CN’177 also teaches generally that the lithium-containing transition metal phosphate coating has a thickness of 0.1 nm to 500 nm, preferably 1 nm to 300 nm, and explains that if the coating is more than 500 nm, electrons cannot penetrate the coating as an insulating material, while if the coating is less than 0.1 nm, the coating effect is not obtained (CN’177, p. 4).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to provide the cobalt compound-containing coating layer of WO’391 with a thickness of about 1 nm to about 50 nm, as suggested by the 20-30 nm coating thickness taught by CN’177, because optimizing the thickness of a surface coating is a result-effective variable in the art of battery materials. A person of ordinary skill would have been motivated to select a thickness within this range to ensure that the coating is thick enough to suppress side reactions with the electrolyte while remaining thin enough to avoid significantly increasing the internal resistance or decreasing the energy density of the cathode active material.
As to Claim 8:WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based secondary particles formed of aggregated primary particles with internal pores and a lithium cobaltate coating (WO’391, pp. 1, 3-7, 13-14, 16-17)); wherein the nickel-based lithium metal oxide secondary particles comprise a compound represented by Formula 1: Liₐ(Ni₁₋ₓ₋ᵧM1ₓM2ᵧ)O₂±α1 (WO’391 teaches Example 1 with the composition Li(Ni₀.₈Co₀.₁₅Al₀.₀₅)O₂ (WO’391, pp. 13-14)); wherein M1 is at least one of Co, Mn, or Al (WO’391 teaches M1 includes Co and Al (WO’391, pp. 13-14)); and wherein 0.95 ≤ a ≤ 1.1 (WO’391 teaches a molar ratio of Li to metal is 1.05 (WO’391, pp. 13-14)); 0.6 ≤ (1−x−y) < 1 (WO’391 teaches the nickel content is 0.8 (WO’391, pp. 13-14)); 0 ≤ x < 0.4 and 0 ≤ y < 0.4 (WO’391 teaches x = 0.2 for the combined Co and Al M1 elements and y = 0 for M2 elements (WO’391, pp. 13-14)); and 0 ≤ α1 ≤ 0.1.
However, WO’391 does not explicitly disclose the use of M2 elements selected from boron (B), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper (Cu), or zirconium (Zr) within the specific crystal structure of the main oxide in Example 1.
CN’177 teaches a nickel-based cathode active material and explicitly discloses the incorporation of dopant elements such as zirconium (Zr), titanium (Ti), and magnesium (Mg) into the transition metal oxide structure to enhance electrochemical performance. CN’177 teaches a lithium-containing transition metal oxide main material AᵝLiₓMᵧN₁₋ᵧO₂₋α, where M includes Ni, Co, and Mn, and N/N′ may include Mg, Ca, Sr, Ba, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Zr, and other elements (CN’177, pp. 2-4). CN’177 further discloses specific nickel-based examples containing Ti, Zr, and Mg, including Li₀.₉₈Ni₀.₆Co₀.₁₈Mn₀.₂Ti₀.₀₂O₂, Li₁.₀₇Ni₀.₈₂Co₀.₁₀Mn₀.₀₇Zr₀.₀₀₄Mg₀.₀₀₂Ti₀.₀₀₄O₂, Li₀.₉₅Ni₀.₉Co₀.₀₅Mn₀.₀₄Mg₀.₀₁O₂, and Li₁.₀₉Ni₀.₈₈Co₀.₁₀Al₀.₀₁Ti₀.₀₁O₂ (CN’177, pp. 7-10, 14-15).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to include at least one of the M2 elements such as zirconium, titanium, or magnesium in the formula of the nickel-based lithium metal oxide taught by WO’391, as suggested by the multi-element transition metal oxides taught in CN’177, because it was routine in the art to use these dopants to stabilize the layered structure and suppress phase transitions during lithium-ion insertion and removal. One of ordinary skill would have been motivated to combine the specific hollow structure and sizing of WO’391 with the doping strategy of CN’177 to achieve the predictable result of a cathode material with both high-rate characteristics and improved cycle life stability.
As to Claim 9:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches a nickel-based cathode active material for lithium secondary batteries comprising secondary particles formed of aggregated primary particles with internal pores and a lithium cobaltate coating (WO’391, pp. 1, 3-7, 13-14, 16-17)); wherein the nickel-based lithium metal oxide secondary particles comprise a compound represented by Formula 2: Liₐ(Ni₁₋ₓ₋ᵧ₋zCoₓM3ᵧM4z)O₂±α1 (WO’391 teaches Example 1 with the composition Li(Ni₀.₈Co₀.₁₅Al₀.₀₅)O₂ (WO’391, pp. 13-14)); wherein M3 is at least one of Mn or Al (WO’391 Example 1 uses Al (WO’391, pp. 13-14)); wherein 0.95 ≤ a ≤ 1.1 (WO’391 teaches a molar ratio of Li to metal is 1.05 (WO’391, pp. 13-14)); 0.6 ≤ (1−x−y−z) < 1 (WO’391 teaches the nickel content is 0.8 (WO’391, pp. 13-14)); 0 ≤ x < 0.4 and 0 ≤ y < 0.4 (WO’391 teaches x = 0.15 for Co and y = 0.05 for Al (WO’391, pp. 13-14)); and wherein a case in which all of x, y, and z are 0 is excluded (WO’391 teaches x and y are greater than 0 (WO’391, pp. 13-14)).
However, WO’391 does not explicitly disclose the use of M4 elements (z > 0) such as boron (B), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper (Cu), or zirconium (Zr) within the specific crystal structure of the main oxide in Example 1.
CN’177 teaches a nickel-based cathode active material and explicitly discloses the incorporation of M4-type dopant elements such as zirconium (Zr), titanium (Ti), and magnesium (Mg) into the transition metal oxide structure to enhance structural stability and electrochemical performance. CN’177 teaches a lithium-containing transition metal oxide main material AᵝLiₓMᵧN₁₋ᵧO₂₋α, where M includes Ni, Co, and Mn, and N/N′ may include Mg, Ca, Sr, Ba, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Zr, and other elements (CN’177, pp. 2-4). CN’177 further discloses specific nickel-based lithium transition metal oxide examples including Li₀.₉₈Ni₀.₆Co₀.₁₈Mn₀.₂Ti₀.₀₂O₂, Li₁.₀₇Ni₀.₈₂Co₀.₁₀Mn₀.₀₇Zr₀.₀₀₄Mg₀.₀₀₂Ti₀.₀₀₄O₂, Li₀.₉₅Ni₀.₉Co₀.₀₅Mn₀.₀₄Mg₀.₀₁O₂, and Li₁.₀₉Ni₀.₈₈Co₀.₁₀Al₀.₀₁Ti₀.₀₁O₂ (CN’177, pp. 7-10, 14-15).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to include at least one of the M4 elements such as zirconium, titanium, or magnesium in the Formula 2 compound of WO’391, as suggested by the multi-element cathode materials taught in CN’177, because it was routine in the art to use these specific dopants to stabilize the layered rock salt structure and minimize lattice distortion during charging and discharging. One of ordinary skill would have been motivated to combine the hollow particle structure of WO’391 with the doping strategy of CN’177 to achieve the predictable result of a cathode material with improved structural integrity and cycle life.
As to Claim 10:
WO’391 discloses the cathode active material of claim 1 (WO’391 teaches nickel-based secondary particles formed of single-crystal primary particles, having internal pores, and a cobalt-based coating (WO’391, pp. 1, 3-7, 13-14, 16-17)); the plurality of large primary particles having a size (WO’391 teaches single-crystal primary particles having an average particle diameter of 0.01 μm or more and 5 μm or less, which encompasses the range of about 2 μm to about 4 μm (WO’391, pp. 1, 3-6, 17)); and the nickel-based lithium metal oxide secondary particles having a size (WO’391 teaches secondary particles with an average diameter of 1 μm to 100 μm, preferably 2 μm to 70 μm, and more preferably 3 μm to 50 μm, which encompasses the range of about 12 μm to about 18 μm (WO’391, pp. 1, 3, 6, 17)).
However, WO’391 does not explicitly recite the specific narrow numerical sub-ranges of about 2 μm to about 4 μm for the primary particles and about 12 μm to about 18 μm for the secondary particles.
CN’177 teaches a nickel-based cathode material where the primary particle size is specifically optimized to be in the range of 2.0 μm to 4.0 μm and the secondary particle size is optimized in a range of 10 μm to 12 μm. Specifically, CN’177 discloses Example 14, in which the main material Li₁.₀₈Ni₁/₃Co₁/₃Mn₁/₃O₂ includes primary particles having an average particle diameter of 2.0 μm to 4.0 μm (CN’177, p. 12), and further discloses Comparative Example 2, in which Li₁.₁₀Ni₁/₃Co₁/₃Mn₁/₃O₂ has secondary particles of 10 μm to 12 μm, with precipitated secondary spherical particles of 10 μm to 13 μm (CN’177, pp. 17-18). A person of ordinary skill in the art would understand that the secondary particle size of 10-12 μm taught by CN’177 is immediately adjacent to and overlaps the lower end of the claimed 12-18 μm range at about 12 μm, and that both references teach that these dimensions are result-effective variables for optimizing the electrode’s packing density and electrochemical stability.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the specific particle size of the primary and secondary particles within the broad ranges disclosed in WO’391 to match the specific optimized parameters taught by CN’177, because both references teach that selecting specific sub-ranges within these dimensions is a matter of routine optimization to improve the filling property of the active material and the overall energy density of the resulting battery.
Claims 22-27 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2012/137391 A1 (WO’391) in view of US 2010/0209763 A1 (US’763).
As to Claim 22:
WO’391 discloses a cathode for lithium secondary batteries (lithium secondary battery 1 including positive electrode plate 2 (WO’391, pp. 1-3)); the cathode comprising a cathode current collector and a cathode active material layer on the cathode current collector (positive electrode plate 2 formed by laminating positive electrode current collector 21 and positive electrode active material layer 22 (WO’391, pp. 2-3)); wherein the cathode active material layer comprises the cathode active material of claim 1 (the layer 22 comprises positive electrode active material particles 222, which are secondary particles formed of aggregated primary particles with internal pores and a lithium cobalt oxide coating as established in the rejection of Claim 1 (WO’391, pp. 3-7, 13-14, 16-17)).
However, WO’391 does not explicitly disclose that the cathode active material layer further comprises “at least one of large particles or aggregates thereof, the large particles having the same composition as the cathode active material” specifically as a second distinct component within the layer to fill gaps.
US’763 teaches an electrode for a non-aqueous electrolyte secondary battery where the active material in the electrode mixture layer comprises “first active material particles” of a substantially spherical shape and “second active material particles” of a non-spherical shape (US’763 [0019], [0036]-[0039]). US’763 explicitly discloses that the “second active material particles are particles of the first active material particles crushed” and are “packed so as to close gaps between the first active material particles” (US’763 [0019], [0036], [0041], [0048]-[0049]). Since these second particles are crushed versions of the first, they are aggregates or particles having the same composition as the first particles (US’763 [0022], [0065], [0071]-[0074]).
WO’391 and US’763 are analogous arts because both are directed to the field of lithium secondary batteries and, more specifically, to the optimization of the cathode active material layer morphology and composition to improve electrochemical performance and packing density (WO’391, pp. 1-7; US’763 [0001]-[0008], [0018]-[0027]).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the cathode of WO’391 to include crushed particles or aggregates of the same composition as the primary active material, as taught by US’763, because incorporating a second population of crushed particles of the same material fills the voids between the spherical secondary particles. This combination results in a higher packing rate and increased energy density for the electrode while ensuring chemical compatibility between the materials within the layer.
As to Claim 23:
WO’391 discloses a cathode for lithium secondary batteries (positive electrode plate 2 of lithium secondary battery 1 (WO’391, pp. 1-3)); comprising a cathode current collector and a cathode active material layer (positive electrode plate 2 formed by laminating current collector 21 and active material layer 22 (WO’391, pp. 2-3)); wherein the cathode active material layer comprises the cathode active material of claim 1 (the layer includes particles 222 which are secondary particles formed by aggregating primary particles (WO’391, pp. 3-4)); and the cathode active material comprises pores having a size (the secondary particles have a large number of pores V with an “average pore size of 0.1 μm to 5 μm inclusive” (WO’391, pp. 1, 4, 6-7, 17)). US’763 teaches a cathode for a secondary battery comprising a current collector and an electrode mixture layer where the active material includes first spherical particles and second crushed particles/aggregates of the same composition packed to close gaps between the first particles to increase packing density (US’763 [0003]-[0004], [0019], [0036]-[0049], [0125]-[0133]).
However, WO’391 does not explicitly recite the specific numerical sub-range of about 0.5 μm to about 4 μm for the pore size in the specific structural combination of first particles and crushed aggregates taught by US’763.
The disclosure of WO’391 renders this limitation obvious because the claimed range of 0.5 μm to 4 μm is a narrow sub-range entirely encompassed by the broader range of 0.1 μm to 5 μm explicitly disclosed in WO’391. WO’391 further teaches that the average pore diameter is a result-effective variable that must be optimized, noting that diameters exceeding 5 μm reduce active material volume and cause stress concentration, while diameters below 0.1 μm hinder electrolyte penetration (WO’391, pp. 6-7). One of ordinary skill in the art would recognize that selecting a sub-range within the 0.1-5 μm envelope is a matter of routine optimization to balance electrolyte access with mechanical integrity.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to optimize the pore size of the hollow cathode active material within the claimed range of 0.5 μm to 4 μm to ensure effective electrolyte infiltration as taught by WO’391, and to combine this with the aggregate-filling strategy of US’763 to achieve the predictable result of an electrode with both high ionic conductivity and superior packing density. Selecting a specific sub-range from a broader disclosed range while incorporating known structural enhancements like crushed aggregates is a matter of routine design choice and routine optimization to achieve known performance benefits.
As to Claim 24:
WO’391 discloses the cathode of claim 22 (positive electrode plate 2 of lithium secondary battery 1; comprising a cathode current collector 21 and a cathode active material layer 22; wherein the cathode active material layer comprises the cathode active material of claim 1 (WO’391, pp. 1-7, 13-14, 16-17)); and wherein the cathode active material is pressed to form the electrode (WO’391 teaches producing a positive electrode plate by pressing the dried active material layer at a pressure of 2,000 kg/cm² (WO’391, p. 14)).
However, WO’391 does not explicitly disclose that “a greater amount of the large particles [aggregates] are in a surface portion of the cathode than in a central portion of the cathode.”
US’763 teaches a method for producing an electrode for a non-aqueous electrolyte secondary battery comprising applying an electrode mixture paste to a current collector and “compressing the coating... to partially crush the first active material particles, so that second active material particles [aggregates/crushed particles] are formed and packed so as to close gaps” (US’763 [0019], [0023], [0036], [0048]-[0049]). A person of ordinary skill in the art would recognize that during the mechanical pressing or rolling of an electrode layer on a substrate, the compressive stress is applied at the outer surface; consequently, the degree of particle crushing and the resulting concentration of crushed aggregates or “large particles” would inherently be greater in the surface portion of the cathode than in the central portion adjacent to the current collector, where the particles are relatively shielded from the primary stress of the press (US’763 [0051]-[0059]).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to utilize the compression and crushing method taught by US’763 for the cathode active material of WO’391, because US’763 teaches that partially crushing the particles to create a second population of aggregates of the same composition fills the gaps between original spherical particles, thereby achieving a higher packing rate than conventional methods (US’763 [0019], [0023]-[0027], [0048]-[0050], [0125]-[0133]). The resulting distribution of more aggregates at the surface is the predictable physical outcome of applying this known processing step to the material taught in the primary reference.
As to Claim 25:
WO’391 discloses the cathode of claim 22 (positive electrode plate 2 of lithium secondary battery 1; comprising a positive electrode current collector 21 and a positive electrode active material layer 22; wherein the cathode active material layer 22 comprises the cathode active material of claim 1, specifically secondary particles 222 having a porous or hollow structure containing pores V (WO’391, pp. 1-4, 6-7, 13-14, 16-17)); and wherein the cathode active material layer is produced by applying a paste and pressing the product (WO’391 teaches that positive electrode active material particles 222, binder, and conductive agent are applied on the current collector and pressed, including pressing at 2,000 kg/cm² in Example 1 (WO’391, pp. 3, 13-14)).
However, WO’391 does not explicitly disclose that “a larger amount of the cathode active material having a hollow structure is in a central portion of the cathode than in a surface portion of the cathode.”
US’763 teaches a method for producing an electrode where an electrode mixture layer includes “first active material particles” (spherical) and “second active material particles” (crushed particles/aggregates). US’763 explicitly discloses a step of “compressing the coating to partially crush the first active material particles” to form the second particles and pack them into gaps (US’763 [0019], [0023], [0036], [0048]-[0049]). A person of ordinary skill in the art would understand that when applying mechanical pressure, such as the 2,000 kg/cm² taught by WO’391, to an electrode layer on a substrate, the compressive force is applied directly to the surface portion and is most intense there. This physical stress gradient causes a higher degree of particle crushing at the surface, while the “central portion” adjacent to the current collector is relatively protected from the peak stress. Consequently, the original hollow secondary particles of WO’391 would remain intact in greater numbers in the central portion than in the surface portion, where they are converted into crushed aggregates (US’763 [0049]-[0052], [0056]-[0059], [0125]-[0131]).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to produce the cathode of WO’391 using the compression and partial crushing parameters taught by US’763, because doing so allows the crushed aggregate material to close gaps between the intact hollow particles, thereby achieving a higher packing rate than conventional electrodes (US’763 [0019], [0023]-[0027], [0048]-[0050], [0125]-[0133]). The resulting distribution—with a larger amount of intact hollow structure material in the central portion and more crushed material at the surface—is the predictable physical result of applying this standard manufacturing step to the porous active material of the primary reference.
As to Claim 26:
WO’391 discloses the cathode of claim 22 (positive electrode plate 2 of lithium secondary battery 1 (WO’391, pp. 1-3)); and wherein the cathode active material layer has a structure (WO’391 teaches a positive electrode active material layer 22 formed by applying a paste to a current collector and drying it to a uniform thickness, such as 50 μm (WO’391, pp. 3, 13-14)).
However, WO’391 does not explicitly use the terms “single layer” or “two layer structure” to describe the active material layer.
US’763 teaches a method for producing an electrode including a current collector and an electrode mixture layer where an electrode mixture paste is applied onto a surface of a current collector and dried to form a coating (US’763 [0019], [0023], [0036], [0048], [0080]-[0083]). The process of a single coating and drying step as described in both WO’391 and US’763 inherently results in a “single layer” structure.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to configure the cathode active material layer of WO’391 into a single-layer or two-layer structure, because the coating processes taught by WO’391 and US’763 inherently produce a single layer, and extending this to two layers is a matter of routine design choice and routine optimization to achieve desired electrode loading and thickness.
As to Claim 27:
WO’391 discloses a lithium secondary battery (lithium secondary battery 1 (WO’391, pp. 1-3)); a cathode (positive electrode plate 2 (WO’391, pp. 2-3)); an anode (negative electrode plate 3 (WO’391, pp. 2-3)); and an electrolyte between the cathode and the anode (electrolyte solution 5 contained in a battery case 6 with the positive and negative plates (WO’391, pp. 2-3)); and wherein the cathode comprises a cathode current collector and a cathode active material layer on the cathode current collector (positive electrode plate 2 formed by laminating positive electrode current collector 21 and positive electrode active material layer 22 (WO’391, pp. 2-3)) comprising the cathode active material of claim 1 (the layer 22 comprises secondary particles 222 formed of aggregated primary particles with internal pores and a lithium cobalt oxide coating (WO’391, pp. 3-7, 13-14, 16-17)).
However, WO’391 does not explicitly disclose that the cathode active material layer further comprises “at least one of large particles or aggregates thereof, the large particles having the same composition as the cathode active material” to close gaps and increase packing density as required by the cathode of claim 22, from which claim 27 depends.
US’763 teaches an electrode for a non-aqueous electrolyte secondary battery where the active material layer comprises “first active material particles” of a substantially spherical shape and “second active material particles” which are non-spherical particles of the first active material particles crushed, i.e., aggregates of the same composition (US’763 [0019], [0036]-[0039]). US’763 explicitly discloses that these second particles are “packed so as to close gaps between the first active material particles” to provide an electrode mixture layer with a higher packing rate (US’763 [0019], [0023], [0040]-[0049], [0125]-[0133]).
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to incorporate the crushed aggregates of the same composition as taught by US’763 into the cathode active material layer of the battery taught by WO’391, because US’763 teaches that doing so fills the gaps between secondary particles, thereby increasing the electrode packing density and overall energy density of the resulting lithium secondary battery (US’763 [0019], [0023]-[0027], [0048]-[0050], [0125]-[0133]). Combining these features would result in the predictable achievement of a high-capacity, high-rate lithium secondary battery.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
KR 101145719 B1 discloses a battery module in which a plurality of plate-shaped battery cells are built in a module case and sequentially stacked.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIMMY K VO whose telephone number is (571)272-3242. The examiner can normally be reached Monday - Friday, 8 am to 6 pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tong Guo can be reached at (571) 272-3066. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JIMMY VO/
Primary Examiner
Art Unit 1723
/JIMMY VO/ Primary Examiner, Art Unit 1723
Prosecution Insights