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 .
Response to Amendment
The amendment filed 10/24/2025 has been entered. Claims 6-9 are pending in this application and examined herein. Claims 10-14 are cancelled.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/24/2025 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 6-9 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 6 recites “wherein Al is present in the form of aluminum oxide”, however the instant specification does not describe Al in the form of aluminum oxide, and therefore does not describe the claimed invention in a manner understandable to a person of ordinary skill in the art in a way that shows that the inventor invented the claimed invention at the time of filing. Correction is required.
Claims dependent upon claim 6, either directly or indirectly, are likewise rejected under this statute.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
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.
Claims 6-9 are rejected under 35 U.S.C. 103 as being unpatentable over He et al. (WO 2014154152 A1, machine translation supplied with Office Action mailed 21 February 2024) in view of Ishida (US 20130269484 A1, cited in Office Action mailed 1 August 2022), further in view of Cao (CN 105907983 A, machine translation, cited in Office Action mailed 1 August 2022), further in view of Furuya (JPH 1197076 A, machine translation; machine translation of family document DE 19842658 A1 used as a supplemental translation, both cited in Office Action mailed 1 August 2022), and further in view of Higuchi (JP 2016191093 A, original document and English abstract provided with IDS filed 04/19/2023, machine translation supplied by Examiner with Office Action mailed 05/10/2023).
Regarding claim 6, He teaches a process for recovering lithium comprising leaching the metallurgical composition by adding a sulfuric acid aqueous solution to the composition [0008, 0014]. He teaches obtaining a residue comprising insoluble compounds and a first leachate comprising lithium and aluminum [0032].
He does not teach leaching until a pH range of 1 to 2 is obtained and does not teach the first leachate comprises 50% or more of the lithium and aluminum from the metallurgical composition.
Ishida teaches a valuable metal leaching method and valuable metal collection method employing the leaching method, where a positive electrode of a lithium ion battery is leached by sulfuric acid at a pH of 0.5-1.5 [0089-0090], creating a leachate containing lithium and aluminum and leaving a residue [0092, 0126]; thus, He and Ishida are analogous as both are drawn to methods of recovering elements from batteries using sulfuric acid leaching. Ishida teaches when the sulfuric acid solution is made to have a pH of 0.5 to 1.5, the reactivity of the sulfuric acid is more preferable [0090].
Further, Ishida teaches that when leaching at a pH of 1.0-1.5 (which is completely within the claimed range), that 97% of lithium and 96% of aluminum are leached (i.e., “50% or more” as claimed; see Ishida Table 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the sulfuric acid leaching of the battery components of He to take place at a constant 1-1.5 pH as taught by Ishida, in order use a pH range with preferable reactivity as taught by Ishida. Doing so would have been further obvious because He teaches that when the first leachate is neutralized, the pH is raised to 3-9 (He: [0021, 0032]), but does not teach the pH of the leachate prior to neutralizing; thus, one of ordinary skill would look to Ishida for a suitable pH to perform the sulfuric acid leaching step.
The starting material of He is waste batteries as opposed to a “metallurgical slag” as claimed. Further He does not teach a first leachate comprising one or more of Ca and Si.
Cao teaches a method of extracting lithium from furnace slag generated from pyrogenic process recovery of lithium battery, where elements are recovered from metallurgical slag containing lithium and aluminum (i.e., providing a lithium- and aluminum-bearing metallurgical slag obtained from a smelting process for recycling lithium-ion batteries or their derived products) [0023] by sulfuric acid leaching [0040], and thus He and Cao are analogous as both are drawn to recovery of lithium from lithium and aluminum containing waste products by sulfuric acid leaching. Cao teaches wherein the metallurgical slag further comprises Ca and Si fluxes (i.e., slag formers selected from Ca and Si) [0005, 0046]. Cao teaches metal and compounds of batteries are oxidized in a slag [0005], which would include the aluminum present (e.g., [0005, 0023]), therefore aluminum would be present in the metallurgical slag in the form of aluminum oxide. Cao teaches such a method not only solves the problem of solid waste disposal, but also increases an important lithium extraction resource and creates huge economic benefits by valorizing slag [0009].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have also used a furnace slag containing lithium and aluminum taught by Cao as the feedstock of the process of He, in order to dispose of a solid waste by producing saleable lithium from the slag as taught by Cao. Further, doing so would increase lithium extraction resource and create economic benefits by valorizing slag as taught by Cao. It would have been further obvious that Ca would be found in the first leachate of He when modified to leach metallurgical slag according to Cao, as Cao teaches Ca to be present in the lithium solution remaining after leaching with sulfuric acid [0057-0058], and filtration [0061], where as He recites the same steps to obtain a first leachate, the lithium solution of Cao is analogous to a first leachate as claimed.
He in view of Ishida and Cao is silent to wherein the first leachate comprises one or more of Ca and Si. However, page 4 lines 10-19 and Table 1 of the present specification discloses Ca and Si to be leached from lithium slag containing slag formers when leaching with sulfuric acid at pH 1.0, 2.0, 2.5, 3.0, or 4.0, in accord with the method as presently claimed. Ishida in view of Cao discloses substantially the same process that Applicant states produces this feature; Cao teaches lithium slag containing Ca and Si flux agents (i.e., slag formers) (Cao: [0005]), leaching the slag with sulfuric acid (Cao: [0040]), and neutralizing the leachate to raise the pH of the leachate to 4-6.5 (which would require the leachate to have been at a pH of less than 4, i.e., for at least some duration either at the claimed pH values during the leaching or during the neutralizing step as the pH is increased to 4-6.5) (Cao: [0051]). Therefore, one of ordinary skill would have a reasonable assumption that the features of claim 6 would also occur when practicing the method of He in view of Ishida and Cao. See MPEP 2112 § (III-V) and 2112.01 § (I).
He teaches neutralizing the first leachate comprising lithium and aluminum to pH 3-9 by adding alkali [0021, 0032]. This overlaps the claimed range of pH 2 to 3. The overlap between the ranges taught in the prior art and recited in the claims creates a prima facie case of obviousness because there is utility over an entire range disclosed in the prior art. See MPEP § 2144.05(I).
He does not teach adding a source of phosphate ions to the first leachate.
Furuya teaches a method for processing battery such as a lithium ion battery [0001], comprising a positive electrode made of an aluminum current collector and a positive electrode active material made of LiCoO2 [0019]. Furuya teaches in Example 6 leaching a battery electrode in sulfuric acid to obtain a leachate, after which the pH is increased using sodium hydroxide [0061-0064, 0069-0070]. Thus, He and Furuya are analogous as both are directed to recovering lithium and other metals from waste lithium ion batteries by sulfuric acid leaching followed by pH neutralization with sodium hydroxide. Furuya teaches the above-mentioned leachate (analogous to a first leachate) pH is brought closer to the neutral range, and adding a source of phosphate ions to the first leachate (comprising lithium and aluminum) thereby precipitating a residue comprising a first part of the aluminum from the first leachate and obtaining a second leachate [0041]. Because Furuya is silent to precipitation of lithium, lithium must be retained in the second solution, and therefore Furuya suggests obtaining a second leachate comprising lithium. Furuya teaches in example 6 that after treatment with sodium hydrophosphate powder, 92.8% of Al is recovered by filtering, implying that 7.2 % of Al to be unrecovered, and thus must remain in the solution; thus, the second leachate also comprises aluminum (Table 5, [0069-0071]). Furuya teaches when phosphoric acid or phosphates are used as a precipitant aluminum can be almost completely precipitated [0041].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added a phosphoric acid or phosphate addition step after neutralizing to pH 3 and before separating a lithium containing solution as taught by Furuya in the process of He, because doing so would remove additional aluminum from the first leachate without coprecipitating cobalt as taught by Furuya, further purifying the leach of impurities, consistent with the objective of He to remove Al impurities and to recover Co (He: [0010]).
He does not teach precipitating a residue comprising a second part of the aluminum from the second leachate and obtaining a third leachate comprising lithium.
Higuchi teaches a method for removing iron and aluminum from lithium ion battery scrap (Title), where the battery scrap is leached with acid, maintaining pH at 4.0 or less [0011], then precipitating iron and also aluminum by adding an oxidizing agent [0011, 0014]. Therefore, He and Higuchi are analogous as both are directed to recycling lithium ion batteries by leaching with sulfuric acid and precipitating aluminum from the leachate. Higuchi teaches after precipitating, if aluminum remains in the leachate the pH may be further adjusted to between 4 and 5.5 to precipitate remaining iron and aluminum (i.e., a second part of aluminum) in the leachate [0012], where lithium remains dissolved in the leachate (analogous to a third leachate comprising lithium) [0013]. Higuchi teaches separating the residue comprising the second part of the aluminum from the third leachate by filtration [0038]. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added a step of adjusting pH to between 4 and 5.5 after adding an agent to precipitate aluminum from a leachate as taught by Higuchi after the step of adding phosphate (which is used to precipitate aluminum) in He as doing so would remove further aluminum from the leachate.
As pH is neutralized to 3 and phosphate ion addition occurs at pH 3 in the above-discussed combination of He in view of Furuya (He: [0021, 0032]), the pH is not less than 3, so the second “neutralizing” step in claim 6 need not be carried out in a method according to that combination.
Regarding claim 7, He teaches after the step of leaching and before the step of adding a source of phosphate, separating the first leachate comprising lithium and aluminum by filtration [0032].
Regarding claim 8, He teaches the first leachate is neutralized and before the step of adding a source of phosphate, filtering to remove aluminum that is precipitated (i.e., separating the second leachate comprising lithium and aluminum by filtration) [0009, 0032].
Regarding claim 9, He teaches obtaining lithium by precipitating lithium carbonate by adjusting the lithium sulfate solution (analogous to a third leachate) to pH 10-12 with sodium hydroxide and adding sodium carbonate (precipitating lithium from the third leachate; He: [0022]), but does not teach separating the lithium by filtration.
Response to Arguments
Applicant's arguments filed 10/24/2025 have been fully considered but they are not persuasive.
Regarding Applicant’s argument that the rejection of claims 6-9 under 35 USC 112(a) as failing to comply with the written description requirement should be withdrawn, as a skilled person would allegedly have understood that the aluminum present in the slag is in an oxide form, (see pg. 4-5 of remarks), the Examiner respectfully disagrees.
As noted by Applicant, the instant application discloses when batteries and flux are melted at high temperature and an oxygen potential, that more easily oxidized elements report to the slag, however the instant specification does not disclose which elements are all present, which among them would be considered “more easily oxidized”, or with respect to which element(s) the “more easily oxidized elements” are more easily oxidized than. Instead, the cited paragraph only discloses formation of a “cobalt-nickel-copper metallic phase”, and thus one of ordinary skill would only be able to determine that cobalt, nickel, and copper may be in a metallic phase, and that at least some elements are oxidized and report to the slag.
While, as Applicant notes, the instant specification discloses that upon leaching the slag, lithium aluminate may problematically precipitate from the leaching solution, where lithium aluminate is an oxide, nothing in the instant specification discloses lithium aluminate (i.e., aluminum oxide) to be present in the slag prior to leaching; instead, the lithium aluminate could be formed e.g., during the leaching or due to changes in conditions of the leachate that result in formation and in turn precipitation of the lithium aluminate.
Regarding Applicant’s argument that Cao does not teach leaching a slag with sulfuric acid to form a leachate comprising Ca or Si (see pg. 5-7 of remarks), the Examiner respectfully disagrees. While He in view of Ishida and Cao is silent to wherein the first leachate comprises one or more of Ca and Si, the instant application discloses Ca and Si to be leached from lithium slag containing slag formers when leaching with sulfuric acid at pH 1.0, 2.0, 2.5, 3.0, or 4.0, in accord with the method as presently claimed, where Ishida in view of Cao discloses substantially the same process that Applicant states produces this feature. Therefore, one of ordinary skill would have a reasonable assumption that the features of claim 6 (leaching of Si and Ca from the lithium slag) would also occur when practicing the method of He in view of Ishida and Cao.
Conclusion
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/NIKOLAS TAKUYA PULLEN/Examiner, Art Unit 1733