DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
This is a final office action in response to Applicant’s remarks and amendments filed on 08/28/2025. Claims 1 and 9 are currently amended. Claims 10-22 remain withdrawn as being drawn to a nonelected invention. Claims 1-2, 4-9, and 23 are presented for examination.
Applicant's amendment to claim 1 has overcome the objection set forth in the pervious Office Action.
The 35 U.S.C. § 103 rejections in the previous Office Action are maintained.
Response to Arguments
Applicant's arguments filed 08/28/2025 have been fully considered but they are not persuasive.
Applicant argues (pp. 10-13) that p. 9 of the previous Office Action states that it would have been obvious to use the particles of Sun in the cathode active material of Park. But the particles of Sun must necessarily include Tungsten (W) as a dopant. Thus, to use the material of Sun in the cathode active material of Park, tungsten must be included as a dopant. However, the cathode active material of the present application does not contain Tungsten.
The Examiner respectfully disagrees. The rejection does not rely on Sun to replace the active materials of Park but rather to teach that a lithium metal oxide particle with a specific surface area of “0.25 m2/g or less” is known in the art and that the specific surface area can modified with predictable effects on the conductivity and stability of the active material. Specifically, increasing the specific surface area improves ion mobility because the active material has more contact with the electrolyte. If the surface area is too high, however, the electrolyte may permeate too far into the active material particles, causing deformation of the active material structure ([0095]). The dopant content of Sun is therefore not pertinent to the rejection of claim 1, though the Examiner notes that Sun further teaches that the specific surface area of the oxide particles increases with increasing tungsten content ([0095]).
Applicant argues (p. 14) that there is no rationale to replace the particles of Sun for the particles of Park, which are disclosed as having a specific surface area higher than the claimed range. Applicant discovered the unexpected advantageous effect of the claimed surface area.
The Examiner respectfully disagrees. A skilled artisan would be motivated to modify the specific surface area to a value lower than that disclosed by Park in order to achieve a desired balance between the tradeoffs described by Sun. As discussed in the previous Office Action, the effects disclosed in the instant specification and the Yoo declaration are predictable based on the disclosure of Sun .
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-2, 4-9, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Park (US 2018/0316009 A1; previously cited) in view of Chen (CN 108091830 A; the rejections below refer to the machine translation mailed 09/27/2024) and Sun (US 2022/0020982 A1; previously cited).
Regarding claim 1, Park discloses a cathode active material comprising a lithium metal oxide particle which includes a layered crystal structure and a cubic (spinel) crystal structure ([0044]) and a coating layer formed on at least a portion of the surface of the lithium metal oxide particle ([0079]), but does not explicitly disclose the claimed coating layer including aluminum and a metalloid (see discussion below).
Park discloses wherein the lithium metal oxide particle contains 80 mol% or more of nickel based on a total of number of moles of all elements except for lithium and oxygen. (Examples 1-4 [0114]-[0121] comprise a core of layered LiNi0.91Co0.04Mn0.05O2 and a shell formed by reacting the core with 2-6 wt% of Co-embedded N-doped carbon nanocrystals. Each core particle has a molar mass of approximately 97.5 u. Adding 6% by weight of Co would increase the molar mass to 105 u, and the resulting composite particle would have the formula LiNi0.91Co0.14Mn0.05O2 and contain 83 mol% of nickel based on a total number of moles of all elements except for lithium and oxygen. Since Co only represents a portion of the mass of Co-NC, and the organic components of the Co-NC particles are removed from the active material particles [0118], the content of nickel in the lithium metal oxide particles of Examples 1-4 is between 83 mol% and 91 mol% based on a total number of moles of all elements except for lithium and oxygen, which reads on the claimed range of “80 mol% or more.”)
Park meets the limitation “the lithium metal oxide particle includes the cubic crystal structure only in a region having a thickness of less than 200 nm from a surface thereof when analyzing a crystal structure thereof by a high-resolution transmission electron microscopy (HR-TEM).” (The lithium metal oxide particles comprise a core having a layered crystal structure and a shell having a cubic (spinel) crystal structure [0044]. The shell comprising the cubic crystal structure has a thickness between 1 to 100 nm [0052], which lies within the claimed range of “a thickness less than 200 nm.” The limitation “when analyzing a crystal structure thereof by a high-resolution transmission electron microscopy (HR-TEM)” does not receive patentable weight because the length described by “thickness” should not vary with the method of measurement. Regardless, TEM analysis of Example 4 of Park demonstrates that the cubic crystal structure was included in a region 10 nm from the surface of the lithium metal oxide particle (Fig. 1C, [0141], and therefore Park also meets the limitation “the lithium metal oxide particle includes the cubic crystal structure only in a region having a thickness of less than 200 nm from a surface thereof when analyzing a crystal structure thereof by a high-resolution transmission electron microscopy (HR-TEM).”)
Park discloses wherein the lithium metal oxide particle is doped with at least one of Ti, Zr, and Mg ([0048]) or is doped with at least one of Al, Ti, Zr, B ([0067]).
Park teaches that the lithium metal oxide particle may have a surface coating layer, which may include one or more of aluminum, boron, and arsenic ([0079]), but does not disclose a coating layer including the particular combination of aluminum and a metalloid (i.e., aluminum and boron or aluminum and arsenic). Park teaches that the active material may be modified beyond the embodiments set forth in the disclosure ([0036]).
Chen teaches a method for coating aluminum oxide and boron oxide on lithium metal oxide particles with high nickel content for use in cathodes ([0002]). Alumina coatings have been widely used to improve the cycle performance of positive electrode active material particles. The addition of boron can improve the discharge capacity and initial efficiency of the battery. Chen teaches that these two coatings, i.e., an aluminum-based coating and a boron-based coating, can be applied to positive electrode material at the same time, thereby reducing process time ([0006]). Therefore, a person having ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to have added a coating layer formed on at least a portion of the surface of the lithium metal oxide particle of Park as taught by Chen, the coating layer including aluminum and boron, a metalloid, with a reasonable expectation that doing so would improve battery performance as taught by Chen ([0006]).
Park teaches that the composite cathode active material may have a specific surface area of about 0.48 m2/g to about 1 m2/g, which is higher than the claimed range. Park teaches that a battery using the active material having a specific surface area in this range has improved cycle characteristics and thermal stability. However, Park does not describe or demonstrate the effects of lower specific surface areas. As Chen is silent as to a specific surface area of the coated lithium metal oxide particles, Park in view of Chen does not disclose wherein the lithium metal oxide particle has a specific surface area of 0.25 m2/g or less.
Sun teaches a cathode active material comprising a lithium metal oxide particle which includes a layered crystal structure and a cubic (spinel) crystal structure ([0057]-[0059]), wherein:
the lithium metal oxide particle contains 85 mol% or more of nickel based on a total number of moles of all elements except for lithium and oxygen ([0097]),
the lithium metal oxide particle includes the cubic crystal structure only in a region having a thickness of less than 50 nm from a surface thereof ([0091]), and
the specific surface area of the particle is between 0.15 m2/g to 0.6 m2/g ([0095]), which overlaps the claimed range of “0.25 m2/g or less.”
Sun further teaches that ion mobility and structural stability are variables that can be modified by adjusting the specific surface area of the active material ([0095]). Increasing the specific surface area improves ion mobility because the active material has more contact with the electrolyte. If the surface area is too high, however, the electrolyte may permeate too far into the active material particles, causing deformation of the active material structure. The precise surface area would therefore have been considered a result effective variable by one having ordinary skill in the art before the effective filing date of the invention. Without showing unexpected results, the claimed specific surface area cannot be considered critical. One of ordinary skill in the art before the effective filing date of the invention would have found it obvious to have optimized, by routine experimentation, the specific surface area of the active material of Park in view of Chen to obtain a desired balance between ion mobility and structural stability as taught by Sun. It has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art [MPEP § 2144.05].
Regarding claim 2, Park in view of Chen and Sun teaches the invention as discussed in claim 1. Park further discloses the lithium metal oxide particle includes the cubic crystal structure only in a region having a thickness of 10 nm from a surface thereof, which reads on the claim range of “a region having a thickness of 25 nm from a surface thereof- (Fig. 1C, [0141]).
Regarding claim 4, Park in view of Chen and Sun teaches the invention as discussed in claim 1. Sun discloses a specific surface area between 0.15 m2/g to 0.6 m2/g ([0095]), which overlaps the claimed range of “0.05 m2/g to 0.25 m2/g.” One of ordinary skill in the art before the effective filing date of the invention would have found it obvious to have optimized, by routine experimentation, the specific surface area of the active material of Park to obtain a desired balance between ion mobility and structural stability as taught by Sun. It has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art [MPEP § 2144.05].
Regarding claims 5 and 6, Park in view of Chen and Sun teaches the invention as discussed in claim 1. Park discloses wherein a total amount of residual lithium present in the lithium metal oxide particle is 847 ppm or less, which reads on the claimed ranges of 6000 ppm or less and 3000 ppm or less (Examples 8 and 9 in Table 6 on p. 12). The active material from examples 1 and 2 were used to prepare the coin cells of examples 8 ([0131]) and 9 ([0133]), respectively. Chen teaches that the aluminum- and boron-based coatings can be applied in the water phase, which efficiently removes impurities on the surface of the active material (Chen: [0027]). Example embodiments of coated active material particles had 700-800 ppm of residual lithium (Chen: [0088] – [0091]). As the lithium metal oxide particles of Park and the coated particles of Chen both have a total amount of residual lithium present that is less than 3000 ppm, it is the Office’s position that the coated cathode active material of modified Park would also have a total amount of residual lithium of “3000 ppm or less” as required by claim 6, which reads on the range of “6000 ppm or less” required by claim 5.
Regarding claim 7, Park in view of Chen and Sun teaches the invention as discussed in claim 1, wherein the coating layer further includes a non-metal (Chen: [0002]; aluminum oxide and boron oxide both contain oxygen, a non-metal).
Regarding claim 8, Park in view of Chen and Sun teaches the invention as discussed in claim 1, wherein the coating layer includes boron (Chen: [0002]).
Regarding claim 9, Park in view of Chen and Sun teaches the invention as discussed in claim 1. Park further discloses that the lithium metal oxide particle is represented by the formula LixNiaCobMcOy, where M is Mn and x, y, a, b and c are a range of 0.9≤x≤1.2, 1.9≤y≤2.1, 0.8≤a≤1, 0≤c/(a+b) ≤0.13 and 0≤c≤0.11. The particles of examples 1-4 have the formula LiNi0.91Co0.04Mn0.05O2 plus an additional amount of Co (see rejection of claim 1), giving x = 1, y = 2, a = 0.91, b=0.04, and c = 0.05. The value of c/(a+b) is 0.05 before any Co is added, so each value is within the claimed range. Increasing the amount of Co in the active material only decreases the value of c/(a+b), so the active material of Park necessarily has the claimed formula.
Regarding claim 23, Park in view of Chen and Sun teaches the invention as discussed in claim 1. Park further discloses a lithium secondary battery (1, Fig. 11, [0098]) comprising: the cathode (3, Fig. 11, [0098]) which comprises the cathode active material according to claim 1 ([0070]); and an anode disposed to face the cathode (2, Fig. 11, [0098]). The active materials of examples 1-4 were used in coin cells containing cathodes and lithium metal anodes ([0132]-[0133]).
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/C.C.D./Examiner, Art Unit 1723 /TIFFANY LEGETTE/Supervisory Patent Examiner, Art Unit 1723