DETAILED CORRESPONDENCE
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
Applicant’s amendment, filed 05/11/2026, has been entered. Claims 1, 7, and 8 are amended. Claim 6 has been cancelled. Claims 1, 3-5, 7, 8, and 18 are now pending examination.
Claim Interpretation
Claim 1 recites “An anode… comprising: …an interphase layer coated on the lithium metal layer”. While the specification also states an anode including an interphase layer [0002], the interphase layer is only ever formed on the separator [0017] [0023] [0092] [0096] [0099] and placed adjacent to the anode [0017]. In accordance with the specification, an anode comprising an interphase layer coated on the lithium metal layer is interpreted to include layers within a separator coated on the lithium metal layer.
Claim 8 recites “an anode having…an interphase layer provided on the lithium metal layer” and is interpreted in the same manner as listed above
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 1, 5, and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Li (US-20200212446-A1) in view of Luan (“Stable Lithium Deposition Enabled by an Acid-Treated g‑C3N4 Interface Layer for a Lithium Metal Anode”) and Cho (KR20190141392A) (see translation mailed 12/08/2025).
Regarding claim 1,
Li teaches an anode (Fig. 2, 22; [0057]) for a lithium rechargeable battery ([0004]-[0005]; [0017]), the anode comprising:
a lithium metal layer [0057];
and an interphase layer (Fig. 2, first layer 210 of protective coating; [0064], “interphase”; [0067]) coated on (see Fig. 2 and [0064]) the lithium metal layer 22,
and wherein the interphase layer 210 is 20 nm to 2 um thick ([0067], entirely within the claimed range of 10 nm to 5um thick),
and wherein the interphase layer 210 comprises polyacrylic acid (PAA) [0067] as a binder (wherein PAA is a type of binder, wherein the limitation “as a binder” is a functional limitation wherein the positively recited structure of the claim is taught, see also [0077] describing relevant function)
but fails to teach wherein the interphase layer includes phosphorus-doped graphitic carbon nitride.
Luan teaches wherein an interphase layer includes graphitic carbon nitride (section 2.1, g-C3N4 used to coat Li foil). It would be obvious to one of ordinary skill in the art before the effective filing date of the present invention to incorporate graphitic carbon nitride into the first layer of Li, as Luan teaches that having graphitic carbon nitride in the interface layer can contribute to more uniform Li deposition and fast ion transfer (see Conclusions section). Luan fails to teach wherein graphitic carbon nitride is phosphorus-doped graphitic carbon nitride.
Cho teaches phosphorus-doped graphitic carbon nitride ([0001], phosphorous-doped graphitic carbon nitride, which is on an interphase layer [0001], “composition for coating a separator”; [0067], “Pg-CN coated separator”; wherein the coating of Cho is an interphase layer because it is a layer between different phases of an electrochemical cell). It would be obvious to one of ordinary skill in the art before the effective filing date of the present invention to use phosphorus-doped graphitic carbon nitride in place of Luan’s undoped graphitic carbon nitride, as Cho teaches phosphorus doping enables chemical adsorption of polysulfides more effectively than undoped graphitic carbon nitride. While Cho’s interphase layer is cathode-facing, the benefit of an affinity for polysulfides is expected regardless of placement on the anode or cathode side.
Regarding claim 5,
Li in view of Luan and Cho teaches the anode of claim 1 (see rejection of claim 1 above), but fails to teach wherein the phosphorus-doped graphitic carbon has a concentration of phosphorus (P) between 1 at. % to 2 at. %. Cho teaches wherein the graphitic carbon has a concentration of phosphorus (P) between 1 to 50 at% (Cho [0038], 1 to 50 at%). It would be obvious to one of ordinary skill in the art before the effective filing date of the present invention to have wherein a concentration of phosphorus (P) between 1 at. % to 2 at. % because Cho discloses an overlapping range [0038]. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. See MPEP § 2144.05.I.
Regarding claim 7,
Li in view of Luan and Cho teaches the anode of claim 6 (see rejection of claim 6 above), wherein a mass ratio of the phosphorus-doped graphitic carbon nitride and the at least one binder is 9:1 to 5:5 (Cho; 30 wt% carbon mixture and 10 wt% binder per Cho [0064], wherein a ratio of 3 to 1 (30%:10% = 3:1) falls within, and thus anticipates, the claimed range of 9:1 to 5:5).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Park (US-20210028484-A1) in view of Luan (“Stable Lithium Deposition Enabled by an Acid-Treated g‑C3N4 Interface Layer for a Lithium Metal Anode”) in view of Cho (KR20190141392A) (see translation mailed 12/08/2025) and Fina (“Structural investigation of graphitic carbon nitride via XRD and Neutron Diffraction”) (refer to enclosed translations for citations).
Regarding claim 3,
Li in view of Luan and Cho teaches the anode of claim 1 (see rejection of claim 1 above), but fails to disclose wherein the phosphorus-doped graphitic carbon nitride has a peak intensity ratio I(002)/I(100). However, phosphorus-doped graphitic carbon nitride is known in the art to have a peak intensity ratio I(002)/I(100) of 6 (see Fina, “XRD analysis” section, wherein the reciprocal of the I(100)/I(002) value .18 is approximately 6 which is substantially close to the claimed range of 7 to 8), wherein the peak intensity ratio is a ratio of a peak for a crystal plane (002) to a peak for a crystal plane (100) obtained in an X-ray diffraction (XRD) spectrum (see Fina, “XRD analysis” section).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention that the phosphorus-doped graphitic carbon nitride of Cho has a peak intensity ratio I(002)/I(100) of 7 to 8. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Park (US-20210028484-A1) in view of Luan (“Stable Lithium Deposition Enabled by an Acid-Treated g‑C3N4 Interface Layer for a Lithium Metal Anode”) in view of Cho (KR20190141392A) (see translation mailed 12/08/2025) and Ma (Phosphorus-Doped Graphitic Carbon Nitrides Grown In Situ on Carbon-Fiber Paper: Flexible and Reversible Oxygen Electrodes) (refer to enclosed translations for citations).
Regarding claim 4,
Li in view of Luan and Cho teaches the anode of claim 1 (see rejection of claim 1 above), but fails to teach wherein the phosphorus-doped graphitic carbon nitride exhibits P=N peak and P-N peak in Pp X-ray photoelectron spectroscopy (XPS). However, the bonding of the phosphorus-doped graphitic carbon nitrides has been shown in Ma (see discussion section, “(P-N bonds confirmed by XPS and FT-IR… π bonds” wherein π bonds implies the presence of P=N bonds).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention that the phosphorus-doped graphitic carbon nitride of Cho would exhibit P=N peak and P-N peak in Pp X-ray photoelectron spectroscopy (XPS) since these bonds are known to be associated with the material, as taught by Ma.
Claims 8 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Li (US-20200212446-A1) in view of Luan (“Stable Lithium Deposition Enabled by an Acid-Treated g‑C3N4 Interface Layer for a Lithium Metal Anode”) and Zhang (“Phosphorus-doped carbon nitride solid: enhanced electrical conductivity and photocurrent generation”).
Regarding claim 8,
Li teaches a lithium rechargeable battery ([0004]-[0005]; [0017]) comprising:
a cathode (Fig. 1, 24; [0017] positive electrode);
an anode (Fig. 1/2, 22; [0047]) having a lithium metal layer [0057],
a separator (Fig. 1, 26; [0047]) disposed between (see Fig. 1) the cathode 24, and the anode 22 comprising an interphase layer (Fig. 2, first layer 210 of protective layer; [0064], “interphase”; [0066])
and an electrolyte (Fig. 1, 30; [0059]) with which the separator 26 is impregnated [0059], “inside pores”),
wherein the interphase layer 210 is disposed between (see [0063-0064], “between” and Fig. 1) the separator 33 and the anode 22 (see Figs. 1 and 2, [0063-0064]),
wherein the cathode 24 comprises a cathode active material [0054], and a conductive agent [0054],
wherein the cathode active material 13 is sulfur free ([0053], see lithium transition metal oxide embodiments which do not contain sulfur),
wherein the interphase layer 210 is 20 nm to 2 um thick ([0067], entirely within the claimed range of 10 nm to 5um thick),
but fails to teach wherein the interphase layer includes phosphorus-doped graphitic carbon nitride.
Luan teaches wherein an interphase layer includes graphitic carbon nitride (section 2.1, g-C3N4 used to coat Li foil). It would be obvious to one of ordinary skill in the art before the effective filing date of the present invention to incorporate graphitic carbon nitride into the first layer of Li, as Luan teaches that having graphitic carbon nitride in the interface layer can contribute to more uniform Li deposition and fast ion transfer (see Conclusions section). Luan fails to teach wherein graphitic carbon nitride is phosphorus-doped graphitic carbon nitride.
However, Zhang teaches phosphorus-doped graphitic carbon nitride (see final paragraph). It would be obvious to one of ordinary skill in the art before the effective filing date of the present invention to dope the graphitic carbon nitride with phosphorus as Zhang teaches phosphorous doping improves conductivity (see final paragraph).
Regarding claim 18,
Park in view of Luan and Zhang teaches the lithium rechargeable battery of claim 8 (see rejection of claim 8 above), wherein the cathode active material [0053] includes lithium manganese oxide ([0053], “lithium manganese oxide”).
Response to Arguments
Applicant’s arguments, see ”Remarks”, filed 05/11/2026, have been fully considered and, due to the amendments are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Li, Luan, and Zhang.
Applicant argues that PAA is not taught. However, this argument is moot in light of updated rejection in view of Li, who teaches PAA for the interphase layer 210 [0066].
Applicant’s arguments regarding Park are moot in light of the updated rejection which no longer relies on Park.
Applicant argues that Cho does not disclose sufficient motivation for combination, because the separator functions as an insulator not a conductor. This argument is not persuasive, as this argument conflates the separator as a whole with each individual layer supported thereon. A separator assembly must electrically isolate the positive and negative electrode from one another, but it does not follow that every coating formed on one surface of the separator must itself be electronically nonconductive. Indeed, Cho itself demonstrates that an electronically functional coating may be supported on one face of a separator. The proposed combination does not require replacing the electrically insulating separator, and Applicant has not provided evidence that providing a conductive coating allows electrons to electrically connect opposed electrodes. Applicant’s position is also inconsistent with the interpretation of “anode” supported by Applicant’s own disclosure. As explained in the claim interpretation above, Applicant’s specification depicts and describes the claimed interphase layer as being formed on the separator adjacent the lithium-metal layer, yet includes that separator-supported layer within the recited anode. Under that interpretation, the fact that Cho’s PgCN-containing layer is likewise formed on a separator does not distinguish it from the claimed interphase layer. The same separator-supported layer cannot render Applicant’s layer part of an anode while categorically preventing the corresponding separator-supported layer of the prior art from satisfying the claim.
Regardless, the motivation for Cho now relies on phosphorus doping to acquire a beneficial affinity for polysulfides (see rejection of claim 1 above), such that applicant’s argument regarding motivation is moot.
Applicant’s Chen citation is also moot based off the updated motivation. Additionally, Chen was published in 2024 and does not represent what one of ordinary skill in the art would have understood at the relevant time (see MPEP 2141).
Applicant argues that all other claims should be allowed based off an allowable claim 1 and 8. However, this is not persuasive, as the rejections of claim 1 and 8 have been sustained.
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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/PAUL CHRISTIAN ST WYROUGH/Examiner, Art Unit 1728
/TIFFANY LEGETTE/Supervisory Patent Examiner, Art Unit 1723
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