Prosecution Insights
Last updated: April 19, 2026
Application No. 18/331,830

PASSIVATION MATERIALS ON ALKALINE EARTH METALS

Non-Final OA §102§103
Filed
Jun 08, 2023
Examiner
ESSEX, STEPHAN J
Art Unit
1727
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Massachusetts Institute Of Technology
OA Round
1 (Non-Final)
65%
Grant Probability
Favorable
1-2
OA Rounds
3y 8m
To Grant
49%
With Interview

Examiner Intelligence

Grants 65% — above average
65%
Career Allow Rate
445 granted / 683 resolved
At TC average
Minimal -16% lift
Without
With
+-16.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 8m
Avg Prosecution
27 currently pending
Career history
710
Total Applications
across all art units

Statute-Specific Performance

§101
0.5%
-39.5% vs TC avg
§103
55.6%
+15.6% vs TC avg
§102
23.0%
-17.0% vs TC avg
§112
17.1%
-22.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 683 resolved cases

Office Action

§102 §103
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 § 102 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. Claims 2-5, 7, 8, 10 and 12-18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Asada et al. (hereinafter “Asada”) (JP 2019-153582 A; see English machine translation). Regarding claims 2, 5, 7, 8, 10 and 16-18, Asada teaches a battery comprising a negative electrode (form of a layer) containing magnesium, and a sulfide solid electrolyte (see paragraph 13). The negative electrode preferably has a coating containing MgS (passivation material) on the surface thereof (form of a layer). The coating is formed by a reaction between sulfur in the sulfide solid electrolyte and magnesium contained in the negative electrode. This MgS is thought to have a narrower band gap and superior electrical conductivity compared to MgO and other materials formed at the interface with other solid electrolytes, and therefore it is presumed that this will suppress an increase in interfacial resistance and reduce the insulating nature of metallic magnesium, thereby enabling further increases in discharge capacity and charge/discharge efficiency. Absent any further teaching within Asada of the inclusion of other elements, including potential impurities, it is presumed that the MgS coating is substantially pure (greater than or equal to 90 mol. %). Regarding claims 3 and 4, Asada teaches that the negative electrode has the formula AXMgYMZ, where X and Z may be zero (see paragraph 14). Thus, the negative electrode may comprise pure magnesium. Regarding claim 12, MgS is known to be a crystalline material having a cubic crystal structure. Regarding claims 13-15, although Asada does not explicitly teach the claimed ionic conductivity, cationic transference number, or anionic transference number of the MgS coating layer, one of ordinary skill in the art would expect the MgS coating layer of Asada to exhibit these properties because the MgS coating layer is substantially identical in composition to the claimed passivation layer. It has been held by the courts that where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. See In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977) (see MPEP § 2112.01). 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. Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Asada as applied to claims 2-5, 7, 8, 10 and 12-18 above. Regarding claim 11, although Asada does not explicitly teach a thickness of the MgS coating layer, it is noted that Asada does teach that a thickness of the negative electrode mixture layer is most preferably no more than 200 µm (see paragraph 44). It is well understood within the art that it is desirable to minimize the thickness of non-active elements of a battery electrode assembly. As such, one of ordinary skill in the art would not expect the MgS coating layer of Asada to have a thickness which is greater than that of the negative electrode mixture layer. Allowable Subject Matter Claims 6 and 9 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEPHAN J ESSEX whose telephone number is (571)270-7866. The examiner can normally be reached Monday - Friday, 8:30 am - 6:00 pm. 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, Barbara Gilliam can be reached at (571) 272-1330. 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. /STEPHAN J ESSEX/Primary Examiner, Art Unit 1727
Read full office action

Prosecution Timeline

Jun 08, 2023
Application Filed
Jan 10, 2026
Non-Final Rejection — §102, §103 (current)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
65%
Grant Probability
49%
With Interview (-16.0%)
3y 8m
Median Time to Grant
Low
PTA Risk
Based on 683 resolved cases by this examiner. Grant probability derived from career allow rate.

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