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 the Claims
This is a final Office action in response to Applicant’s amendments and remarks filed on 04/03/2026. Claims 1-5, 8, 10-12, 14, 16-17, 19-20, and 23-26 are pending in the current Office action. Claims 6, 9, 13, and 21-22 were cancelled by Applicant. Claims 1 and 2 were amended by applicant. Claims 23-26 are new claims.
Status of the Rejection
The rejections of claims 1-5, 8, 10-12, 14, 16-17, 19-20 under 35 U.S.C. § 112(b) are withdrawn in view of Applicant’s amendments.
The rejections of claims 1-5, 8, 10-12, 14, 16-17, 19-20 under 35 U.S.C. § 103 are withdrawn in view of Applicant’s amendments.
New rejections of claims 1-5, 8, 10-12, 14, 16-17, 19-20 and 23-26 are necessitated by Applicant’s amendments.
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.
Claims 1-5, 8, 10-12, 14, 16-17, 19-20 and 23-26 are rejected under 35 U.S.C. 112(a) as failing to comply with the written description requirement due to the inclusion of new matter. The claims contain 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, had possession of the claimed invention.
Regarding claims 1 and 2, claims 1 and 2, as currently amended, recite the limitation “maintaining the cathode at a fixed electrochemical potential within a window between about 0.6 and about -0.2 V vs. Ag/AgCl during lithium intercalation”. Support for this limitation could not be identified in the specification as originally filed.
Specifically, Applicant has indicated support for this limitation may be found on p. 5 2nd and 4th para.; p. 10 2nd para; page 12 1st para; p. 24 3rd para.; and Figs. 2 and 3 of the substitute specification dated 08/28/2025.
Of these, p. 24 3rd para. describes a constant voltage of 2.0 V for the electrodialysis step, but does not describe a fixed potential for the lithium intercalation step. None of the other indicated sections of the support describe the use of a fixed potential during the lithium intercalation step i.e., step (ii).
Page 4 of the specification reads “steps (ii) and (iii) are conducted at a voltage of between about 0.6 and about -0.2 V vs Ag/AgCl”, and p. 8 of the specification reads “the operating voltage is between about 0.6 V and about -0.2 V vs. Ag/AgCl”, however neither of these statements is considered to supply for a “fixed voltage” as recited in the claims as currently amended. No portions of the specification as originally filed could be identified describing the use of a “fixed voltage” during the intercalation step. It is therefore considered that this limitation constitutes new matter not included in the specification as originally filed.
Claims 1 and 2 are therefore rejected under 35 U.S.C. § 112(a) for failing to comply with the written description requirement due to the inclusion of new matter.
Regarding claims 3-5, 8, 10-12, 14, 16-17, 19-20 and 23-26, these claims depend from claim 1 or 2, and therefore incorporate the new matter recited in those claims. Claims 3-5, 8, 10-12, 14, 16-17, 19-20 and 23-26 are therefore rejected under 35 U.S.C. § 112(a) for failing to comply with the written description requirement due to the inclusion of new matter.
Allowable Subject Matter
Claims 1-5, 8, 10-12, 14, 16-17, 19-20 and 23-26 would be allowable if rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112(a) set forth in this Office action, or upon a showing of support for the limitations considered new matter.
Regarding claims 1 and 2, the prior art of record, alone or in combination, does not reasonably teach or disclose the cumulative limitations of claims 1 or 2, with a particular emphasis on the limitations “(ii) intercalating lithium ions onto a cathode comprising an intercalation material comprising lithium iron phosphate, iron phosphate (FePO4), or any combination thereof”, “maintaining the cathode at a fixed electrochemical potential within a window between about 0.6 and about -0.2 V vs Ag/AgCl during lithium intercalation” and “the continuous single-pass flow-by operation provides a lithium purity greater than 90%”.
The closest prior art is considered to be Cui (WO 2021/188570 A2), Kim et al. (“Rapid and selective lithium recovery from desalination brine using an electrochemical system” Environ. Sci.: Processes Impacts, 2019, 21, 667), Calvo (US Pat. Pub. 2014/0076734 A1), Vulcan (WO 2021/204375 A1), Presser (WO 2022/207449 A2 with citations to US Pat. Pub. 2024/0166535 A1 as the official English translation on file with the Office), and Mislan (US Pat. Pub. 2020/0283921 A1)/
As described more fully in the Office action mailed 01/08/2026, Cui teaches a method for recovering lithium from brine, the method comprising intercalating lithium into iron phosphate (para. 8) using an applied electrochemical potential between about -0.11 and about -0.16 V vs Ag/AgCl, a range within the claimed range (Fig. 2A), wherein a lithium purity of about 100% is achieved (para. 32).
However, Cui teaches this purity is achieved by the use of a pulsed electrochemical method, and that the use of a fixed electrochemical potential results in reduced purity (see Fig. 2D). It is therefore considered that a person having ordinary skill in the art would not have expected that a lithium purity greater than 90% could be achieved using a fixed electrochemical potential within a window between about 0.6 and about -0.2 V vs Ag/AgCl via a lithium intercalation method as claimed based on the teachings of Cui.
As more fully detailed in the Office action mailed 09/05/2025, Kim teaches a method for recovering lithium from brine via intercalation, but uses manganese oxide as the intercalation material, rather than iron phosphate as claimed. It is therefore considered that Kim would not have provided a person having ordinary skill in the art with a motivation to modify the method of Cui.
As more fully detailed in the Office action mailed 05/22/2025, Calvo teaches a method for recovering lithium from brine via intercalation, but uses manganese oxide as the intercalation material, rather than iron phosphate as claimed. It is therefore considered that Calvo would not have provided a person having ordinary skill in the art with a motivation to modify the method of Cui.
Vulcan teaches a method for recovering lithium from brine, but does not involve an electrochemical intercalation step, as described in the Office action mailed 05/22/2025.
Presser teaches a method for recovering lithium from brine (para. 35) via intercalation, wherein iron phosphate is used as the intercalation material (para. 14), and a voltage between -0.4 and 0.4 V is applied during the intercalation step (para. 77), but Presser does not use a fixed potential, but rather a fixed current (para. 77). Additional teachings of Presser are detailed in the Office action mailed 01/08/2026.
Mislan teaches a method for recovering lithium from brine via intercalation (abstract), but does not detail the electrochemical parameters used.
It is therefore considered that the prior art of record, alone or in combination, does not reasonably teach or render obvious the cumulative limitations of claims 1 or 2. Claims 1 and 2 are therefore considered patentably distinguished over the prior art of record, and would be allowable if the rejections under 35 U.S.C. § 112(a) are appropriately addressed.
Regarding claims 3-5, 8, 10-12, 14, 16-17, 19-20, and 23-26 these claims depend from claims 1 or 2, and therefore incorporate the allowable subject matter of claims 1 or 2. These claims would therefore be allowable over the prior art at least the same reasons enumerated for claims 1 or 2, above, if the rejections under 35 U.S.C. § 112(a) are addressed.
Response to Arguments
Applicant’s arguments, see Remarks p. 6-10, filed 04/03/2026, with respect to the rejections under 35 U.S.C. § 103 have been fully considered and are persuasive. The rejections under 35 U.S.C. § 103 have been withdrawn.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
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/ALEXANDER R. PARENT/Examiner, Art Unit 1795
/ALEXANDER W KEELING/Primary Examiner, Art Unit 1795
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