Prosecution Insights
Last updated: April 19, 2026
Application No. 18/549,348

METHOD FOR RECOVERING LITHIUM PRECURSOR FROM LITHIUM SECONDARY BATTERY

Non-Final OA §103
Filed
Sep 07, 2023
Examiner
GREGORIO, GUINEVER S
Art Unit
1732
Tech Center
1700 — Chemical & Materials Engineering
Assignee
SK Innovation Co. Ltd.
OA Round
1 (Non-Final)
73%
Grant Probability
Favorable
1-2
OA Rounds
3y 4m
To Grant
91%
With Interview

Examiner Intelligence

Grants 73% — above average
73%
Career Allow Rate
600 granted / 825 resolved
+7.7% vs TC avg
Strong +18% interview lift
Without
With
+18.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 4m
Avg Prosecution
28 currently pending
Career history
853
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
57.7%
+17.7% vs TC avg
§102
9.7%
-30.3% vs TC avg
§112
20.0%
-20.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 825 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 . 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. 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(s) 1-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Na et al. (EP 3767737) in view of Wang (CN106848472; translation provided by Google Patents 02/04/2026). Regarding claim 1, Na et al. teaches a method for recovering an active metal of a lithium secondary batter which meets the preamble method for recovering a lithium precursor from a lithium secondary battery (paragraph 2). Na et al. teaches cathode active material mixture may be prepared in a powder form through a physical method such as grinding which meets the limitation preparing cathode powder from a cathode of the lithium secondary battery (paragraph 42). Na et al. teaches the recovered cathode may be thermally treated before the grinding treatment at a temperature of 100 to 500 ̊C (paragraph 43). Na et al. teaches the cathode active material mixture may be subjected to a hydrogen reduction to prepare the preliminary precursor mixture which meets the limitation of reducing the cathode active material mixture to form a preliminary precursor mixture (paragraph 46). Na et al. teaches premium lithium precursor may be obtained as a lithium precursor substantially consisting of lithium hydroxide which meets the limitation of recovering a lithium precursor from the preliminary precursor mixture (paragraph 55). Na et al. does not teach preparing a cathode active material mixture by mixing the cathode powder with a calcium compound. Wang teaches a method for efficiently recovering lithium from waste lithium which comprises the steps of roasting and sorting the waste lithium iron phosphate batteries to obtain lithium-containing positive electrode powder (abstract). Wang teaches spraying calcium-containing powder to absorb the generation of fluorine-containing gas in the roasting process at a roasting temperature is 200-1200 ℃ (page 2, lines 1-5; page 3). It would have been obvious to one of ordinary skill in the art at the time of filing to spray calcium powder during the thermal treatment step taught by Na et al. because calcium-containing powder absorbs the generation of fluorine-containing gas. Regarding claim 2, Na et al. teaches a used cathode which meets a broad and reasonable interpretation of wherein the cathode comprises a waste cathode derived from scrap (paragraph 40). Regarding claim 3, Na et al. teaches cathode active material mixture may be prepared in a powder form through a physical method such as grinding which meets the limitation wherein the step of preparing the cathode powder comprises dry pulverizing the cathode of the lithium secondary battery (paragraph 42). Regarding claim 4, Na et al. teaches a used cathode which meets a broad and reasonable interpretation of wherein the cathode comprises a current collector and a cathode active material layer formed on the current collector and including a binder and a cathode active material, and the cathode powder comprises components derived from the cathode active material and the binder (paragraph 40). Regarding claims 5-7, Wang teaches a method for efficiently recovering lithium from waste lithium which comprises the steps of roasting and sorting the waste lithium iron phosphate batteries to obtain lithium-containing positive electrode powder (abstract). Wang teaches spraying calcium-containing powder to absorb the generation of fluorine-containing gas in the roasting process at a roasting temperature is 200-1200 ℃ which meets a broad and reasonable interpretation of reacting a component derived from the binder with the calcium compound to at least partially remove the component (page 2, lines 1-5; page 3). Wang teaches calcium oxide (page 2). It would have been obvious to one of ordinary skill in the art at the time of filing to spray calcium powder during the thermal treatment step taught by Na et al. because calcium-containing powder absorbs the generation of fluorine-containing gas. Regarding claim 8, Wang teaches the mass ratio of the battery waste to the calcium-containing powder is 0.1-3000 which encompasses wherein reacting the calcium compound with the cathode powder comprises mixing the cathode powder with a calcium compound containing 0.5 to 1.5 times more calcium element than fluorine element contained in the cathode powder (page 2). Regarding claim 9, Wang teaches spraying calcium-containing powder to absorb the generation of fluorine-containing gas in the roasting process at a roasting temperature is 200-1200 ℃ which encompasses wherein the step of preparing the cathode active material mixture comprises performing heat treatment on the cathode powder and the calcium compound together at a temperature of 300 to 600°C (page 2, lines 1-5; page 3). Regarding claims 10, and 11, Na et al. teaches the cathode active material mixture may be subjected to a hydrogen reduction to prepare the preliminary precursor mixture which meets the limitation of wherein the reduction treatment comprises dry reduction using a hydrogen gas (paragraph 46). Na et al. taches hydrogen reduction at a temperature range of 400 to 700 ℃ which encompasses 400 to 600°C (paragraph 53). Regarding claim 12, Na et al. teaches preliminary lithium precursor may be obtained as a lithium precursor substantially composed of lithium hydroxide by the water washing treatment which meets the limitation of wherein the step of recovering the lithium precursor from the preliminary precursor mixture comprises obtaining a lithium precursor hydrate by washing the preliminary precursor mixture with water (paragraph 55). Regarding claim 13, Na et al. in view of Wang does not teach wherein a selectivity of lithium hydroxide in the lithium precursor hydrate is 97% or more. It is clear that the percentage of the lithium hydroxide taught by Na et al. in view of Wang would necessarily produce a selectivity of lithium hydroxide in the lithium precursor hydrate is 97% or more because the method of making taught by Na et al. in view of Wang is the same or similar method of claimed. 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. I, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01 (I). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to GUINEVER S GREGORIO whose telephone number is (571)270-5827. The examiner can normally be reached M-W 11 am - 9 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, Coris Fung can be reached at 571-270-5713. 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. /GUINEVER S GREGORIO/Primary Examiner, Art Unit 1732 02/04/2026
Read full office action

Prosecution Timeline

Sep 07, 2023
Application Filed
Feb 04, 2026
Non-Final Rejection — §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
73%
Grant Probability
91%
With Interview (+18.5%)
3y 4m
Median Time to Grant
Low
PTA Risk
Based on 825 resolved cases by this examiner. Grant probability derived from career allow rate.

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