Prosecution Insights
Last updated: July 15, 2026
Application No. 17/760,813

Separation Membrane for Electrochemical Device, Electrochemical Device Comprising Same Separation Membrane, and Method for Manufacturing Same Separation Membrane

Final Rejection §103
Filed
Mar 16, 2022
Priority
Oct 18, 2019 — RE 10-2019-0130071 +1 more
Examiner
ZEMUI, NATHANAEL T
Art Unit
1727
Tech Center
1700 — Chemical & Materials Engineering
Assignee
LG Energy Solution Ltd.
OA Round
6 (Final)
56%
Grant Probability
Moderate
7-8
OA Rounds
0m
Est. Remaining
80%
With Interview

Examiner Intelligence

Grants 56% of resolved cases
56%
Career Allowance Rate
264 granted / 472 resolved
-9.1% vs TC avg
Strong +24% interview lift
Without
With
+24.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 7m
Avg Prosecution
48 currently pending
Career history
530
Total Applications
across all art units

Statute-Specific Performance

§101
0.4%
-39.6% vs TC avg
§103
89.6%
+49.6% vs TC avg
§102
6.0%
-34.0% vs TC avg
§112
2.2%
-37.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 472 resolved cases

Office Action

§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 . Status of Claims Claims 1 & 15 are amended. Claims 2-3, 5, 10, 12-14 & 18-20 are canceled. Claims 1, 4, 6-9, 11, 15-17 & 21-23 are currently pending. 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. 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, 4, 6-9, 11, 15-17 & 21-23 are rejected under 35 U.S.C. 103 as being unpatentable over Ohata (US 2006/0216608 A1) in view of Yeou (US 2015/0200399 A1). Regarding claims 1, 4, 7-9, 11, 15-17 & 21-23, Ohata teaches an electrochemical device comprising a negative electrode, a positive electrode, and a free-standing separator interposed between the negative electrode and the positive electrode, wherein the separator excludes a separator substrate formed of a polymer resin film and includes an insulating porous layer alone having a thickness of 6 microns and comprising 60 wt% to 99 wt% of inorganic particles having an average particle diameter of 0.01 microns to 0.5 microns and 1 wt% to 40 wt% of a resin binder comprising an elastomer such as BM720H (i.e corresponding to a hydrogenated nitrile butadiene rubber) with the content of inorganic particles and the resin binder in certain other embodiment ranging from 92.6 wt% to 98.5 wt% and from 1.5 wt% to 7.4 wt% respectively (Table 5: Examples 1-11; [0057], [0072]-[0074], [0077]-[0079] & [0199]-[0201]). Ohata further teaches an exemplary embodiment H2 in which the binder resin includes 20 wt% of an elastomer such as BM500B (i.e a rubber including acrylonitrile) as a first binder and 80 wt% PVDF as a second binder ([0060]-[0069], [0105] & [0127]-[0134]; Table 3). While Ohata doesn’t disclose the molecular weight of BM500B, Ohata discloses another exemplary elastomer such as BM720H which has a known molecular weight of 300,000 g/mol as evidenced by Yeou ([0113]). Regarding claim 6, Ohata teaches the free standing separator of claim 1 but is silent as to the elastomer having a molecular weight (Mw) of 600,00 g/mol to 1,000,000 g/mol. Yeou teaches a battery comprising a separator comprising an insulating porous layer comprising inorganic particles and a binder ([0099]-[0100] & [0107]), wherein the binder comprises a fluoropolymer such as PVDF and a nonfluoropolymer including a repeating unit derived from an acryl monomer and a repeating unit derived from an olefin monomer ([0042]-[0052]) or a repeating unit derived from a nitrile monomer such as acrylonitrile and a linear alkylene monomer such as 1,3-butadiene ([0058]-[0060]) which reads on the claimed nitrile butadiene rubber. It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to use a nitrile butadiene rubber having a molecular weight (Mw) of 100,00 g/mol to 1,000,000 g/mol because such as material is known to be suitable for a binder which can be combined with a filler to form a freestanding separator for a battery as taught by Yeou ([0020], [0057]-[0060] & [0099]-[0100]). Moreover, it would have been obvious to one of ordinary skill in art, before the effective filing date of the present invention, to further include a nonfluoropolymer including a repeating unit derived from an acryl monomer and a repeating unit derived from an olefin monomer such as poly(propylene-acrylate), reading on the claimed olefin-based thermoplastic elastomer, along with the nitrile butadiene rubber employed in Ohata as a suitable binder for forming a free-standing separator composed of inorganic particles and a binder. "It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art." In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) (citations omitted) (Claims to a process of preparing a spray-dried detergent by mixing together two conventional spray-dried detergents were held to be prima facie obvious.). See also In re Crockett, 279 F.2d 274, 126 USPQ 186 (CCPA 1960). See MPEP 2144.06 I. Response to Arguments Applicant's arguments filed 02/10/2026 have been fully considered but they are not persuasive. In response to applicant’s arguments that Ohata as modified by Yeou does not fairly teach or suggest the subject matter of claims 1 & 15, the examiner respectfully disagrees. As noted in the above rejection of claims 1 & 15 and contrary to Applicant’s assertions, Ohata teaches an exemplary embodiment H2 (Table 3) using a 20 wt% of a first binder comprising an elastomer and 80 wt% of a second binder comprising PVDF. Accordingly, Applicant’s arguments that Ohata does not fairly teach or suggest a resin binder mixture having the claimed composition is not found to be persuasive. With regards to Applicant’s arguments that Ohata does not teach or suggest a free-standing membrane, it is noted that the inorganic porous layer of Ohata does not have any conventional polyolefin substrate. Accordingly, the inorganic porous layer of Ohata reads on the claimed free-standing separator. Specifically, the inorganic porous layer of Ohata, which can be provided as a single layer or two-layer structure, alone acts as a separator for a battery without the need for any substrates other than the positive electrode or negative electrode on which it is deposited to form the battery. Thus, in view of the foregoing, claims 1, 4, 6-9, 11, 15-17 & 21-23 stand rejected. 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. Contact Information Any inquiry concerning this communication or earlier communications from the examiner should be directed to NATHANAEL T ZEMUI whose telephone number is (571)272-4894. The examiner can normally be reached M-F 8am-5pm (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, BARBARA GILLIAM can be reached on (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. /NATHANAEL T ZEMUI/Examiner, Art Unit 1727
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Prosecution Timeline

Show 10 earlier events
Aug 12, 2025
Final Rejection mailed — §103
Oct 14, 2025
Applicant Interview (Telephonic)
Oct 14, 2025
Examiner Interview Summary
Nov 12, 2025
Request for Continued Examination
Nov 13, 2025
Response after Non-Final Action
Nov 28, 2025
Non-Final Rejection mailed — §103
Feb 10, 2026
Response Filed
Apr 14, 2026
Final Rejection mailed — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12658433
POSITIVE ELECTRODE ACTIVE MATERIAL AND LITHIUM SECONDARY BATTERY COMPRISING THE SAME
5y 2m to grant Granted Jun 16, 2026
Patent 12658468
ELECTROLYTE AND POWER STORAGE DEVICE
3y 8m to grant Granted Jun 16, 2026
Patent 12658483
BUTTON-TYPE SECONDARY BATTERY
2y 10m to grant Granted Jun 16, 2026
Patent 12633531
POSITIVE ELECTRODE AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY USING THE SAME
3y 5m to grant Granted May 19, 2026
Patent 12597636
SOLID-STATE COMPOSITE POLYMER ELECTROLYTE MEMBRANE AND ALL-SOLID-STATE LITHIUM ION BATTERY INCLUDING THE SAME
3y 0m to grant Granted Apr 07, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

7-8
Expected OA Rounds
56%
Grant Probability
80%
With Interview (+24.0%)
3y 7m (~0m remaining)
Median Time to Grant
High
PTA Risk
Based on 472 resolved cases by this examiner. Grant probability derived from career allowance rate.

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