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 .
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 2, and 8-21 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2019/146216 A1 (refer to equivalent US 2020/0350623 for paragraph numbers), both references of which were cited in the Information Disclosure Statement dated October 14, 2022, and further in view of CN 106068573 A, of which a copy of the Chinese document was provided with the Information Disclosure Statement dated February 11, 2025, and with a machine translation being provided with the Office Action mailed May 12, 2025, and further in view of WO 2012/176604 A1, of which a copy of the Japanese document with a machine translation is provided with the Office Action mailed September 30, 2025.
Regarding independent claim 1 and claim 2, WO ‘216 (US ‘623) discloses a positive electrode material that comprises the following components (see abstract; paragraphs [0020], [0023]-[0083], [0144]-[0165], [0182], and [0206]-[0212]; and Figure 1 – refer to paragraphs [0144]-[0165] and Figure 1 for positive electrode material components):
a first solid electrolyte (111);
a positive electrode active material (110);
a coating material (113) coating a surface of the positive electrode active material (110), wherein
the first solid electrolyte (111) is represented by a following compositional formula (1) … LiaMbXc, in which the compositional formula is as follows:
a, b, and c are positive real numbers and satisfy a mathematical expression:
a + b < c;
M is at least one selected from the group consisting of metallic elements excluding Li and metalloid elements (see paragraph [0033]); and
X is at least one selected from the group consisting of F, Cl, Br, and I (see paragraph [0034]).
WO ‘216 (US ‘623) does not explicitly disclose that the coating material includes an oxoacid salt of a non-metal or metalloid cation, and the oxoacid salt includes lithium silicophosphate.
However, CN ‘573 discloses a positive electrode material of a lithium ion secondary battery (abstract; and pages 2 and 12 of translation), in which the positive electrode material includes a coating film material of at least one of lithium phosphate (Li3PO4) or lithium difluorophosphate (LiPO2F2), both of which are oxoacid salts of a metalloid cation since these materials includes phosphorus (P), of which the coating film material is advantageous for improving the capacity of the lithium ion secondary battery conservation rate, and thus improving the cycle characteristics of the lithium ion secondary battery (see page 2 of translation under “invention contents”; and page 12 of translation at the 2nd paragraph above “Claims”). CN ‘573 further discloses that the oxoacid salt includes phosphorus (P), which is present in the coating film material of at least one of lithium phosphate (Li3PO4) or lithium difluorophosphate (LiPO2F2) – see page 2 of translation under “invention contents” of CN ‘573. In addition, CN ‘573 discloses that the oxoacid salt includes lithium (Li) as an element within both lithium phosphate (Li3PO4) or lithium difluorophosphate (LiPO2F2) – see page 2 of translation under “invention contents” of CN ‘573.
It would have been obvious to one of ordinary skill in the art at the time the applicants’ invention was made to modify the coating material in the positive electrode material disclosed by WO ‘216 (US ‘623), by using a coating film that comprises an oxoacid salt of a non-metal or metalloid cation, as taught by CN ‘573, in order to improve the capacity of the lithium ion secondary battery conservation rate, and to improve the cycle characteristics of the lithium ion secondary battery (CN ‘573; see page 2 of translation under “invention contents”; and page 12 of translation at the 2nd paragraph above “Claims”).
The combined teachings of WO ‘216 (US ‘623) and CN ‘573 do not disclose that the oxoacid salt includes lithium silicophosphate.
However, WO ‘604 discloses a lithium ion secondary battery (abstract; pages 3-8 of translation; and Figures 1-3), in which the lithium ion secondary battery includes a layer of an oxoacid salt in the form of lithium silicophosphate, wherein the use of lithium silicophosphate is advantageous as a material having low electron conductivity and high lithium ion conductivity (see the paragraph on page 8 of translation under the heading “(Material of solid electrolyte))”.
It would have been obvious to one of ordinary skill in the art at the time the applicants’ invention was made to modify the coating material in the positive electrode material disclosed by WO ‘216 (US ‘623), by using a coating film that comprises an oxoacid salt of a non-metal or metalloid cation, as taught by CN ‘573, in order to improve the capacity of the lithium ion secondary battery conservation rate, and to improve the cycle characteristics of the lithium ion secondary battery, and by further using lithium silicophosphate as a material of the coating film in CN ‘573, in order to obtain low electron conductivity and high lithium ion conductivity (see WO ‘604 in the paragraph on page 8 of translation under the heading “(Material of solid electrolyte))”.
Although the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest the features of independent claim 1, none of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 explicitly disclose that the surface of the positive electrode active material is “partially covered by the coating material”, as well as that a coverage rate as a proportion of a coated surface area of the positive electrode active material coated with the coating material to the whole surface area of the positive electrode active material is between about 10% and 90%. However, one of ordinary skill in the art would have recognized that an extent of the surface being “partially covered by the coating material” and at a proportion of “coverage rate” (broadly interpreted as having a rather similar meaning) would have been subject to routine optimization while being obvious to try since it would include a limited number of predictable solutions (over an entire range of from a totally coated surface to a totally exposed surface) with a reasonable expectation for success in obtaining improved performance of the battery by increasing its charge capacity (see paragraph [0020] of WO ‘216 (US ‘623)), and by improving cycle characteristics of the battery (see page 2 of translation under “invention contents” of CN ‘573).
Regarding claims 8-10, although the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest the features of independent claim 1, none of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 explicitly disclose that a mass proportion of the oxoacid salt to the positive electrode active material is between any of 0.1 to 2.3 mass%, 0.1 to 2.0 mass%, or 0.25 to 1.14 mass%. However, one of ordinary skill in the art would have recognized that selection of the ranges of mass% to be within the claimed ranges would be readily adjusted by routine experimentation to optimize performance of the battery by increasing its charge capacity (see paragraph [0020] of WO ‘216 (US ‘623)), and by improving cycle characteristics of the battery (see page 2 of translation under “invention contents” of CN ‘573). Moreover, it would have been obvious to one of ordinary skill in the art at the time of the invention to choose the instantly claimed ranges through process optimization, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. See In re Boesch, 205 USPQ 215 (1980).
Regarding claim 11, WO ‘216 (US ‘623) discloses that M includes Y (see paragraphs [0040] and [0041] of US ‘623).
Regarding claims 12-14, WO ‘216 (US ‘623) discloses that X includes at least one (and at least two) of F, Cl, and Br (including both Cl and Br – see paragraph [0034] of US ‘623).
Regarding claim 15, WO ‘216 (US ‘623) discloses that the positive electrode active material (110) includes a lithium-containing transition metal oxide in the form of Li(NiCoMn)O2, or NCM (see paragraph [0208] of US ‘623).
Regarding claims 16 and 17, the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest a battery (1000) that comprises the following structural features (refer to paragraphs [0023]-[0030] and Figure 1 of US ‘623 for battery structure):
a positive electrode (201) including the positive electrode material according to claim 1 (of the combined teachings of WO ‘216 (US ‘623) and CN ‘573);
a negative electrode (104); and
an electrolyte layer (103) disposed between the positive electrode (201) and the negative electrode (104), wherein the electrolyte layer (103) includes a sulfide solid electrolyte (see paragraphs [0138] and [0182] of US ‘623).
Regarding claims 18 and 19, although the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest the features of independent claim 1 (including that X of the compositional formula LiaMbXc is at least one selected from the group consisting of F, Cl, Br, and I (see paragraph [0034] of US ‘623)), none of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 explicitly disclose that the first solid electrolyte (111) of the compositional formula LiaMbXc includes that X consists of F and I (claim 18), as well as that X consists of at least one selected from the group consisting of F and I, and at least one selected from the group consisting of Br and Cl (claim 19). However, since WO ‘216 (US ‘623) discloses that X is at least one selected from the group consisting of F, Cl, Br, and I (see paragraph [0034] of US ‘623), one of ordinary skill in the art would have recognized that any one, any two, any three, or all four elements would be selected via routine experimentation since these elements are in the same group (halogens) of the periodic table and operably form halide salts, in which any combination of these related elements would be obvious to try since it results in a limited number of predictable solutions with a reasonable expectation of success, with such routine experimentation being advantageous to optimize performance of the battery by increasing its charge capacity via use of a halide solid electrolyte with high ion conductivity and excellent thermal stability (see paragraphs [0035] and [0036] of US ‘623).
Regarding new claim 20, although the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest the features of independent claim 1, none of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 explicitly disclose that the surface of the positive electrode active material has the coating material thereon at a thickness within a range of 1 nm to 100 nm. However, one of ordinary skill in the art would have recognized that selection of a value in the range of the coating material thickness to be within the claimed range would be readily adjusted by routine experimentation to optimize performance of the battery by increasing its charge capacity (see paragraph [0020] of WO ‘216 (US ‘623)), and by improving cycle characteristics of the battery (see page 2 of translation under “invention contents” of CN ‘573), wherein a controllable degree of suppression of electron transfer between the positive electrode active material and the first solid electrolyte would be obtained as a function of the coating material thickness. Moreover, it would have been obvious to one of ordinary skill in the art at the time of the invention to choose the instantly claimed ranges through process optimization, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. See In re Boesch, 205 USPQ 215 (1980).
Regarding new claim 21, although the combined teachings of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 disclose/suggest the features of independent claim 1, including source(s) of lithium, silicon, and phosphorus, none of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 explicitly disclose that the coating material is formed in situ by reacting a lithium source, a silicon source, and a phosphorus source on the surface of the positive electrode active material during a heat treatment. However, it is noted that the claimed “coating material” (composition) does not require any process steps from which it is made (being forming in situ and being subject to heat treatment), and how the coating material is made lacks patentable weight since the claims are not method claims that involve the heat treatment process of lithium, silicon, and phosphorus.
Response to Arguments
The examiner acknowledges the applicants’ amendment provided with the request for continued examination received by the USPTO on November 21, 2025. The applicants have cancelled claim 3 (to include its limitations into independent claim 1), and have also added new claims 20 and 21 that are addressed at the end of the above 35 USC 103 rejection (see above section 4). Claims 1, 2, and 8-21 are currently under consideration in the application.
Applicants' arguments filed November 21, 2025 have been fully considered but they are not persuasive.
With regard to the applicants’ remarks/arguments on pages 5-8 of the amendment, the applicants first argue (in the last full paragraph on page 5 of the REMARKS section) that the cited references fail to teach the feature “the coating material includes an oxoacid salt of a non-metal or metalloid cation, the oxoacid salt includes lithium silicophosphate, and a coverage rate as a proportion of a coated surface area of the positive electrode active material coated with the coating material to a whole surface area of the positive electrode active material is 10% or more and is 90% or less”. In the paragraph bridging pages 5 and 6 of the REMARKS section, the applicants summarize the manner in which the Office Action concluded that the combination of the three prior art references render obvious independent claim 1 (in this instance, the combination of independent claim 1 and (cancelled) claim 3, as amended).
In the paragraphs under the headings “1. Functional mismatch between WO ‘604 and CN ‘573” and “2. No explicit motivation to use LiSiPO4 as coating” on page 6 of the REMARKS section, the examiner respectively disagrees that “a surface coating film” of CN ‘573 cannot be combined with the teaching of “lithium silicophosphate layer” as a “solid electrolyte” rather than as a “surface coating”. Moreover, the use of lithium silicophosphate (in WO ‘604) for “bulk ionic conduction within a solid electrolyte”, rather than for “surface modification” does not preclude the obviousness of using lithium silicophosphate (LiSiPO4) therein. Although the examiner acknowledges the applicants’ statement of primary design considerations that include “interfacial compatibility, chemical stability, and surface reaction control”, the use of a specified material (LiSiPO4) as a “layer” rather than a “surface coating”, as applied in the respective references, would render obvious that lithium silicophosphate as an advantageous material in a more comprehensive manner (as a layer, surface coating, another location etc.) and not as a mere “repurpose” of an electrolyte material for a coating application, such that its use would be desirable for obtaining low electron conductivity and high lithium ion conductivity (see WO ‘604 in the paragraph on page 8 of translation under the heading “(Material of solid electrolyte))”.
In the paragraph under the heading “3. Combination requires hindsight” bridging pages 6 and 7 of the REMARKS section, the examiner respectively disagrees with the applicants’ assertion of “hindsight reconstruction” in stating that the combination of references would result in a “multi-step, layered substitution”. As stated in the above section applied to applicants’ headings 1. and 2., the use of lithium silicophosphate (LiSiPO4) as an advantageous material (oxoacid salt) would be viewed by one of ordinary skill in the art more comprehensively (for the reasons above) rather than in the specific manner that the applicants set forth in independent claim 1. In response to applicants' argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
With regard to the applicants’ arguments (on pages 7 and 8 of the REMARKS section) pertaining to the claimed “coverage rate”, and taken in view of the combined teachings of the three references (WO ‘216 (US ‘623), CN ‘573, and WO ‘604), the examiner acknowledges the applicants’ experimentation of the range of 10% to 90% in which the coating simultaneously “suppresses interfacial side reactions” and “maintains electronic conduction pathways”. However, as set forth in the above sections that address applicants’ remarks/arguments in headings 1., 2., and 3., the advantages of the material as a whole, namely lithium silicophosphate (LiSiPO4) as an oxoacid salt, would render its use obvious in the combined references per the motivation applied in view of WO ‘604. Furthermore, regarding the (broad) range of 10% to 90% in the absence of no explicit teaching by any of WO ‘216 (US ‘623), CN ‘573, and WO ‘604 (as argued by applicants in the paragraph bridging pages 7 and 8 of the REMARKS section, as well as the first two full paragraphs on page 8 of the REMARKS section), one of ordinary skill in the art would have recognized that an extent of the surface being “partially covered by the coating material” and at a proportion of “coverage rate” would have been subject to routine optimization while being obvious to try since it would include a limited number of predictable solutions (over an entire range of from a totally coated surface to a totally exposed surface) with a reasonable expectation for success in obtaining improved performance of the battery by increasing its charge capacity (see paragraph [0020] of WO ‘216 (US ‘623)), and by improving cycle characteristics of the battery (see page 2 of translation under “invention contents” of CN ‘573).
In view of the 35 USC 103 rejection and for these additional reasons, claims 1, 2, and 8-21 are rejected.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KEVIN P KERNS whose telephone number is (571)272-1178. The examiner can normally be reached Monday-Friday 8am-430pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at (571)272-3458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KEVIN P KERNS/Primary Examiner, Art Unit 1735 January 9, 2026