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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-11, in the reply filed on December 2, 2025 is acknowledged. As claims 12-16 have been cancelled, the restriction requirement filed November 20, 2025 no longer applies to this application and is withdrawn. The resulting claims pending for examination are claims 1-11.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on March 23, 2023 and April 30, 2024 have been considered by the examiner.
Claim Rejections - 35 USC § 102
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.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 3-7, and 9-11 are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Minami, et al. (US 2017/0309950 A1).
Regarding claim 1, Minami teaches a negative electrode for a secondary battery including negative electrode active material particles (lithium silicate composite oxide particles) including a lithium silicate, silicon particles, and a metallic compound (¶ [0008], Ln. 1-7). Minami teaches that the lithium silicate phase is preferably composed mainly of Li2SiO3 or Li2Si2O5 in terms of stability, manufacturability, and lithium ion conductivity (¶ [00312], Ln. 6-9), specifically teaching negative electrode active material particles including Li2SiO3, Si, and ZrO2 in Example 1 (¶ [0056], Ln. 1-6). As Example 1 teaches negative electrode active material particles including Li2SiO3, Si, and ZrO2 without the addition of Li2Si2O5, the phase fraction ratio of I(225)/I(213), wherein I(225) is the phase fraction of Li2Si2O5 and I(213) is the phase fraction of Li2SiO3, meets the limitation of 1.0 or less.
Minami further teaches that the negative electrode active material particles of Example 1 are passed through a 4.0 µm mesh sieve prior to coating with carbon, and the average particle size is adjusted to 5 µm with a sieve after coating with carbon (¶ [0056], Ln. 11-18). Thus, the negative electrode active material particles of Example 1 do not include particles having a diameter of less than 3 µm, meeting the limitation of having a content of particles having a diameter of less than 3 µm of 5 vol% or less.
Regarding claims 3-4, Minami teaches all of the limitations of claim 1 above and further teaches that the Si, Li2SiO3, and ZrO2 of Example 1 are mixed at a mass ratio of 42:58:1 (¶ [0056], Ln. 1-6). Therefore, the content of a lithium element contained in the negative electrode active material particles is approximately 8.9% by weight, within the claimed range of 2-10 wt% and 4-9 wt%.
Regarding claim 5, Minami teaches all of the limitations of claim 1 above and further teaches that the average particle size of the negative electrode active material particles is adjusted to be 5 µm using a sieve (¶ [0056], Ln. 18-19). Minami teaches that the average particle size is the particle size at which the integrated volume is 50% in the particle size distribution (D50) (¶ [0040], Ln. 1-10).
Regarding claims 6-7, Minami teaches all of the limitations of claim 1 above and further teaches that the negative electrode active material particle includes an electrically conductive layer on its surface (¶ [0045], Ln. 1-3). Minami teaches that the electrically conductive agent of the electrically conductive layer is preferably carbon, specifically carbon black, acetylene black, ketjen black, or graphite (¶ [0045], Ln. 10-20). In Example 1, the negative electrode active material particles are mixed with coal pitch and heated to form a carbon covering (amorphous carbon including soft carbon) (¶ [0056], Ln. 11-17).
Regarding claim 9, Minami teaches all of the limitations of claim 1 above and further teaches that the negative electrode may include another active material in addition to the negative electrode active material particles, teaching that the other active material is preferably a carbonaceous negative electrode active material such as graphite (¶ [0029], Ln. 9-16). Bulk graphite is included in the negative electrode of Example 1 (graphite-based particles including at least one of natural and artificial graphite) (¶ [0059], Ln. 1-4).
Regarding claim 10, Minami teaches all of the limitations of claim 9 above and further teaches that the negative electrode active material particles (lithium silicate composite oxide particles), bulk graphite powder, CMC, and SBR, are included in the negative electrode in a mass ratio of 30:70:1:1 in the negative electrode of Example 1, resulting in a content of negative electrode active material particles of 30 wt% based on the total weight of the negative electrode active material particles and bulk graphite powder, within the claimed range of 5-40 wt% (¶ [0059], Ln. 1-4).
Regarding claim 11, Minami teaches a non-aqueous electrolyte secondary battery including the negative electrode meeting the limitations of claim 1 above, a positive electrode, and a separator disposed between the positive electrode and negative electrode (anode facing the cathode) (¶ [0018], Ln. 1-6). Minami teaches that the positive electrode is a layered lithium composite oxide (lithium secondary battery) (¶ [0020], Ln. 1-2).
Claim Rejections - 35 USC § 103
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Minami, et al. (US 2017/0309950 A1) as applied to claim 1 above, and further in view of Hirose, et al. (US 11,005,095 B2).
Regarding claim 2, Minami teaches all of the limitations of claim 1 above, teaching that the lithium silicate phase is preferably composed mainly of Li2SiO3 or Li2Si2O5 in terms of stability, manufacturability, and lithium ion conductivity (¶ [00312], Ln. 6-9). Minami does not expressly teach an embodiment in which both Li2SiO3 and Li2Si2O5 are included in the negative electrode active material particles, such that the phase fraction ratio I(225)/I(213) is 0.05-0.8.
Hirose teaches a negative electrode active material including a negative electrode active material particle including a silicon compound particle (Col. 7, Ln. 29-31). The silicon compound particle includes crystalline Li2Si2O5 as the main Li silicate, and Li2SiO3 and Li4SiO4 are also present in the bulk of the silicon compound particle (Col. 10, Ln. 19-24). Hirose teaches that Li2Si2O5 has a higher water resistance than both Li2SiO3 and Li4SiO4, and the presence of Li2Si2O5 improves the water resistance and thus increases the slurry stability (Col. 7, Ln. 53-62).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the lithium silicate phase of Minami to include both Li2SiO3 and Li2Si2O5-, based on the teachings of Hirose. One of ordinary skill in the art would be motivated to include Li2Si2O5- in addition to Li2SiO3 in the negative electrode active material particles of Example 1 in order to improve the water resistance and therefore increase the stability of the slurry. It would be obvious to one of ordinary skill in the art to include Li2Si2O5- with reasonable expectation of success, as Li2Si2O5- is already taught as a by Minami to include in the lithium silicate phase. One of ordinary skill in the art would find it obvious to include small amounts of Li2Si2O5 in the negative electrode active material particle of Minami-, such that the lithium silicate phase is still composed mainly of Li2SiO3. In including Li2Si2O5 in an amount such that the lithium silicate phase is still composed mainly of Li2SiO3, it would be obvious to one of ordinary skill in the art to include an amount such that the resulting phase fraction ratio I(225)/I(213) is within the claimed range of 0.05-0.8.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Minami, et al. (US 2017/0309950 A1) as applied to claim 6 above, and further in view of Tsukigata, et al. (US 2024/0274803 A1).
Regarding claim 8, Minami teaches all of the limitations of claim 6 above and further teaches that the electrically conductive layer preferably has a thickness in the range of 1-200 nm, forming a layer thick enough to impart electrical conductivity and cover the base particle, and thin enough to allow diffusion of lithium ions into the base particle (¶ [0047], Ln. 1-11). Minami does not expressly teach that the content of the amorphous carbon is in a range of 1-25 wt% based on a total weight of the negative electrode active material particle.
Tsukigata teaches a negative electrode active material including silicon monoxide particles covered with carbon coating and doped with lithium (¶ [0064], Ln. 1-4), further teaching that the lithium doping is performed such that the lithium is present as Li2SiO3 (¶ [0082], Ln. 12-13). Tsukigata teaches that the carbon coating is preferably 1.0-5.0 mass% relative to an entirety of the coated particle (¶ [0081], Ln. 1-3). Tsukigata teaches that this range ensures sufficient conductivity without being excessive, such that charge and discharge capacities are achieved (¶ [0081], Ln. 6-12).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the electrically conductive layer of Minami to be included in a content within 1.0-5.0 mass% based on the teachings of Tsukigata. One of ordinary skill in the art would be motivated to include the carbon coating within this range in order to ensure sufficient conductivity without compromising charge and discharge capacities.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SARAH J JACOBSON whose telephone number is (703)756-1647. The examiner can normally be reached Monday - Friday 8:00am - 5:00pm.
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/SARAH J JACOBSON/Examiner, Art Unit 1785
/MARK RUTHKOSKY/Supervisory Patent Examiner, Art Unit 1785