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 and Claim Status
The amendment filed 25 May 2026 has been entered. Claim 4 is canceled. Claims 1–3 and 5–19 are pending in the application. Claims 15–19 are withdrawn from consideration.
Specification
The disclosure is objected to because of the following informalities:
[0048]: “short-circuit of a cell dead lithium formation” should instead read “short-circuit of a cell, dead lithium formation”.
Appropriate correction is required.
Claim Objections
Claims 1 and 12 are objected to because of the following informalities:
Claim 1: “wherein the precursor sheet having a thickness” should instead read “wherein the precursor sheet has a thickness”;
Claim 12: “in the heat-treating the precursor, the precursor is heat-treated by” should instead read “in the heat-treating the precursor sheet, the precursor sheet is heat-treated by”.
Appropriate correction is required.
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.
Claims 1, 2, and 5–11 are rejected under 35 U.S.C. 103 as being unpatentable over Cook et al. (US 2017/0350846 A1; art already of record) in view of Yang et al. (“Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes”; art already of record), further in view of Yao et al. (US 2021/0013498 A1; art already of record), and further in view of Park et al. (KR 2020/0001244 A; see provided machine translation).
Regarding Claim 1, Cook discloses a method for manufacturing a porous structure (see top electrode 302, [0057]; note [0057] discloses the top electrode 302 may have a random 3D porosity), the method comprising:
preparing a precursor (see ink, [0057]) by mixing first nanoparticles (see structural material, [0057]; note [0057] discloses the structural material can be in nanoparticle form) and second nanoparticles (see sacrificial nanoparticles, [0057]);
producing a precursor sheet by applying the precursor as an ink ([0057]–[0058]; note that one of ordinary skill in the art will understand that an “applied ink” will necessarily be in the form of a sheet);
heat-treating the precursor sheet (see sintered, [0058]); and
etching the second nanoparticles in the heat-treated precursor sheet (see removed using temperature, solvent, dry vapor phase etch, etc., [0059]).
Cook does not disclose the method for manufacturing being directed to an anode comprising the porous structure for lithium batteries, nor wherein the method comprises disposing lithium metal on the porous structure. Instead, Cook discloses that the porous structure (302) is a conductive plate having a random three-dimensional porosity that is permeable to a reagent ([0060]) and is utilized as an electrode in a capacitive sensor ([0027]–[0028]). Note that Cook is analogous to the claimed invention as it is in the same field of methods for manufacturing porous structures utilized in electrochemical devices.
Yang teaches that three-dimensional porous structures can also advantageously be utilized as current collectors in anodes of lithium metal batteries to aid in eliminating Li dendrite formation and improving lifespan (p. 2 ¶ “As a key component…”). Yang also teaches that an essential step in the formation of such anodes for lithium metal batteries is disposition, i.e. plating, of lithium metal on the porous structure (e.g. p. 2 ¶ “As a key component…” discloses growth of lithium on the porous structure to achieve the anode, p. 3 ¶ “Li-metal deposition…” discloses investigation of lithium plating behavior on the porous structure, and p. 7 ¶ “Electrochemistry. CR2032-type…” discloses deposition of lithium on the porous structure prior to regular battery cycling). Note that Yang is analogous to the claimed invention as it is in the same field of lithium batteries.
In light of the above, it would have been obvious to a person of ordinary skill in the art to use the method for manufacturing a porous structure of Cook such that it is a method for manufacturing an anode comprising a porous structure for lithium batteries, with the method comprising disposition of lithium metal on the porous structure, as Yang teaches that three-dimensional porous structures can be advantageously utilized as current collectors in anodes of lithium batteries to aid in eliminating Li dendrite formation and improving lifespan, and that disposition of lithium metal on the porous structure is an essential step of formation of such an anode.
Modified Cook does not disclose wherein the method comprises producing a precursor sheet by calendaring the precursor, and instead, as set forth above, discloses producing the precursor sheet by application of the precursor as an ink (Cook [0057]–[0058]).
Yao teaches a method for manufacturing an anode (see electrodes, [0046]) comprising a porous structure (see porosity profile, [0045]) for lithium batteries (see lithium-ion battery), [0051]). Yao teaches ([0063]) that calendaring a battery structure such as an electrode enables a desired thickness and porosity of the structure to be achieved, and is performed by compressing the structure between two rollers. Note that Yao is analogous to the claimed invention as it is in the same field of lithium batteries.
It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of modified Cook such that the method further comprises a step of calendaring the precursor in order to produce the precursor sheet, as taught by Yao, for the purpose of achieving a desired thickness and porosity for the precursor sheet.
Modified Cook does not teach wherein the precursor sheet has a thickness of 20 µm to 80 µm. However, it can be reasonably understood by a person of ordinary skill in the art based on the disclosure of Cook that the thickness of the final porous structure will essentially be the same as, and thus be the result of, the thickness of the precursor sheet used to form it (e.g. [0060] discloses that the porous structure is the result of the fused first nanoparticles with pores wherever the second nanoparticles were located; i.e. the porous structure is essentially the precursor sheet with the second nanoparticles removed and pores formed in their places, and would thus have the same thickness as the precursor sheet).
Park teaches a method for manufacturing an anode (see electrode, [0012]) comprising a porous structure (see porous current collector, [0011]) for lithium batteries (see lithium secondary battery, [0013]). Park teaches ([0060]) that when the porous structure has a thickness of 20 µm to 100 µm, battery capacity can be secured because the amount of active material filled in the porous structure is sufficient, and further no rapid resistance increase due to an overly thick electrode occurs, which would degrade battery performance.
Park is analogous to the claimed invention as it is in the same field of lithium batteries. It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of modified Cook such that the precursor sheet has a thickness of 20 µm to 100 µm, as Park teaches that this thickness of the final porous structure results in secured battery capacity due to sufficient filling of active material and undegraded battery performance because a rapid resistance increase due to an overly thick electrode will not occur, and it can be understood from the disclosure of Cook that the thickness of the final porous structure will result from and be essentially the same as the thickness of the precursor sheet.
When the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists (MPEP § 2144.05.I). It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to select the overlapping portions of the ranges for the thickness of the precursor sheet with a reasonably expectation that such selection would successfully result in a secured battery capacity due to sufficient filling of the active material and undegraded battery performance because a rapid resistance increase due to an overly thick electrode will not occur.
Regarding Claim 2, modified Cook discloses the method as set forth above. Cook further discloses ([0037]) wherein the precursor further comprises a binder.
Regarding Claim 5, modified Cook discloses the method as set forth above. Cook further discloses wherein the first nanoparticles comprise at least one of a lithiophilic material (see silver, gold, graphene, graphite, [0039]) or a conductive metal (see copper, [0039]).
Regarding Claim 6, modified Cook discloses the method as set forth above. Cook further discloses ([0039]) wherein the lithiophilic material comprises at least one of silver (Ag), gold (Au), or carbon (C).
Regarding Claim 7, modified Cook discloses the method as set forth above. Cook further discloses ([0039]) wherein the conductive metal comprises copper (Cu).
Regarding Claim 8, modified Cook discloses the method as set forth above, but does not disclose wherein a mass ratio of the first nanoparticles to the second nanoparticles ranges from about 1:0.3 to about 1:1.2.
However, Cook discloses ([0057]–[0060]) that the second nanoparticles form the random 3D porosity of the porous structure, with pores left behind in the final structure wherever the second nanoparticles were located. One of ordinary skill in the art can therefore understand that increasing the mass ratio of the first nanoparticles to the second nanoparticles will decrease the porosity of the porous structure.
A result-effective variable is a variable which achieves a recognized result. The determination of the optimum or workable ranges of a result-effective variable is routine experimentation and therefore obvious (MPEP § 2144.05.II). In the instant case, the mass ratio of the first nanoparticles to the second nanoparticles is a variable that achieves the recognized result of affecting the porosity of the porous structure, as implicitly disclosed by Cook, thus making the mass ratio of the first nanoparticles to the second nanoparticles a result-effective variable. Therefore, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of modified Cook such that a mass ratio of the first nanoparticles to the second nanoparticles ranges from about 1:0.3 to about 1:1.2 via routine experimentation, for the purpose of achieving a porous structure with a suitable level of porosity.
Regarding Claim 9, modified Cook discloses the method as set forth above. Cook further discloses wherein the second nanoparticles comprise at least one of organic particles (see PMMA (polymethyl methacrylate), PVP (polyvinylpyrrolidone), [0057]) or inorganic particles (see SiO2, SiN, ZnO, [0057]).
Regarding Claim 10, modified Cook discloses the method as set forth above. Cook further discloses ([0057]) wherein the organic particles comprise poly(methyl methacrylate).
Regarding Claim 11, modified Cook discloses the method as set forth above. Cook further discloses ([0057]) wherein the inorganic nanoparticles comprise silica (SiO2).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Cook et al. (US 2017/0350846 A1; art already of record) in view of Yang et al. (“Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes”; art already of record), further in view of Yao et al. (US 2021/0013498 A1; art already of record), and further in view of Park et al. (KR 2020/0001244 A; see provided machine translation) as applied to Claim 2 above, further in view of Tanaka et al. (US 2022/0246904 A1; art already of record).
Regarding Claim 3, modified Cook discloses the method as set forth above, but does not disclose wherein an amount of the binder ranges from about 3 to about 50% by weight based on the total amount of the precursor.
Tanaka teaches a method for manufacturing an anode (see negative electrode 1, [0025]) comprising a porous structure (see current collector 11, [0025]) for lithium batteries (see lithium-ion secondary batteries, [0025]). Tanaka teaches ([0055]) that the amount of binder included during the formation of a battery structure such as an electrode affects the ion conductivity, capacity density, and mechanical strength of the battery structure. Note that Tanaka is analogous to the claimed invention as it is in the same field of lithium batteries.
A result-effective variable is a variable which achieves a recognized result. The determination of the optimum or workable ranges of a result-effective variable is routine experimentation and therefore obvious (MPEP § 2144.05.II). In the instant case, the amount of binder is a variable that achieves the recognized result of affecting the ion conductivity, capacity density, and mechanical strength of the manufactured porous structure, as taught by Tanaka, thus making the amount of binder a result-effective variable. Therefore, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of Cook such that the amount of the binder ranges from about 3 to about 50% by weight based on the total amount of the precursor via routine experimentation, for the purpose of achieving suitable levels of ion conductivity, capacity density, and mechanical strength of the porous structure.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Cook et al. (US 2017/0350846 A1; art already of record) in view of Yang et al. (“Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes”; art already of record), further in view of Yao et al. (US 2021/0013498 A1; art already of record), and further in view of Park et al. (KR 2020/0001244 A; see provided machine translation) as applied to Claim 1 above, further in view of Khazaka et al. (US 2018/0374813 A1; art already of record).
Regarding Claim 12, modified Cook discloses the method as set forth above, but does not explicitly disclose wherein, in the heat-treating the precursor sheet, the precursor sheet is heat-treated by raising the temperature from room temperature to about 240 °C to 260 °C at a rate of about 30 °C/min so that the first nanoparticles are welded to each other. However, Cook discloses ([0042]) that sintering the first nanoparticles to form a solid structure, i.e. so that the first nanoparticles are welded to each other, can be performed by heating the first nanoparticles to an elevated temperature, but that the first nanoparticles need not be heated to the melting point of the metal that forms the nanoparticles. Note that Cook also discloses that the first nanoparticles can comprise silver ([0039]).
Khazaka teaches a precursor (see paste, [0105]) comprising silver nanoparticles ([0105]), and a method of heat-treating (see sintering, [0111]) the precursor by raising the temperature to 250 °C at a rate of 5 °C/min so that a final joint of silver is formed ([0111]; one of ordinary skill in the art will understand that forming a final joint of silver is analogous to the silver nanoparticles being welded to each other). Khazaka does not explicitly teach that the starting temperature for the heat-treating is room temperature, however one of ordinary skill in the art would reasonably assume this to be the case. Note that Khazaka is analogous to the claimed invention as it is in the same field of conductive nanoparticles.
KSR Rationale D states that it is obvious to apply a “known technique to a known method ready for improvement to yield predictable results” (MPEP § 2141). It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of modified Cook such that in the heat-treating the precursor sheet, the precursor sheet is heat-treated by raising the temperature from room temperature to 250 °C at a rate of 5 °C/min so that the first nanoparticles are welded to each other, as Khazaka teaches that this is a known technique to yield the predictable result of welding first nanoparticles to each other when the first nanoparticles comprise silver (Ag).
Claims 13 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Cook et al. (US 2017/0350846 A1; art already of record) in view of Yang et al. (“Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes”; art already of record), further in view of Yao et al. (US 2021/0013498 A1; art already of record), and further in view of Park et al. (KR 2020/0001244 A; see provided machine translation) as applied to Claim 1 above, further in view of Sugawara (US 2016/0185932 A1; art already of record) and Gardner et al. (US 2014/0078644 A1; art already of record).
Regarding Claims 13 and 14, modified Cook discloses the method as set forth above, but does not disclose wherein, in the etching the second nanoparticles, the heat-treated precursor sheet is treated with an acid solution to remove the second nanoparticles (Claim 13), nor wherein the acid solution comprises hydrofluoric acid (HF) and at least one of methyl alcohol, ethyl alcohol, isopropyl alcohol, or any combination thereof (Claim 14). Cook instead discloses ([0059]) that the second nanoparticles can be removed using temperature, solvent, dry vapor phase etch, etc., depending on the types of first and second nanoparticles. Note that Cook also discloses ([0057]) that the second nanoparticles can be silica (SiO2).
Sugawara teaches a method for manufacturing a porous structure (see polyimide resin film, [0029]) for lithium batteries (see lithium ion secondary battery, [0107]), the method comprising: preparing a precursor (see varnish, [0031]) by mixing a first component (see polyamide acid or polyimide, [0031]) and second nanoparticles (see fine particles, [0031], which can be silica, [0033]; note that [0037] discloses that the fine particles can have particle diameters ranging from 100 to 2000 nm, and therefore can be nanoparticles); heat-treating the precursor ([0082]); and dissolving and removing, i.e. etching, the second nanoparticles in the heat-treated precursor ([0086]). Sugawara teaches ([0086]) that when the second nanoparticles comprise silica, the heat-treated precursor can be treated with an acid solution to remove the second nanoparticles, and that the acid solution comprises hydrofluoric acid (HF). Note that Sugawara is analogous to the claimed invention as it is in the same field of methods for manufacturing porous structures for batteries.
Sugawara discloses that the acid solution comprises hydrofluoric acid in low concentration, but does not disclose any other components, e.g. the diluent, present in the acid solution.
Gardner teaches a method for manufacturing a porous structure (see porous silicon structure, [0029]) for batteries (see energy storage device 101, [0022], which can be e.g. a battery, [0016]). Gardner teaches ([0029]) that an acid solution for etching of silicon substrates can comprise hydrofluoric acid (HF) and an alcohol such as ethyl alcohol, methyl alcohol, or isopropyl alcohol.
KSR Rationale D states that it is obvious to apply a “known technique to a known method ready for improvement to yield predictable results” (MPEP § 2141). It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of modified Cook such that in the etching of the second nanoparticles, the heat-treated precursor sheet is treated with an acid solution to remove the second nanoparticles (Claim 13), and wherein the acid solution comprises hydrofluoric acid (HF) and at least one of methyl alcohol, ethyl alcohol, isopropyl alcohol (Claim 14), as the combined teachings of Sugawara and Gardner show that this is a known technique to yield the predictable result of removing second nanoparticles when the second nanoparticles comprise silica.
Response to Arguments
Applicant’s arguments in the Remarks filed 25 May 2026 have been fully considered but are not persuasive for the following reasons:
Applicant argues on p. 5 of Remarks that Cook does not teach or suggest the step of fabricating a precursor sheet by calendaring, and only discusses methods such as inkjet print and screen printing for manufacturing a permeable top electrode.
This argument is not persuasive. While it is the case that Cook only discloses ([0057]–[0058]) fabricating a precursor sheet by application of the precursor as an ink, as set forth in the rejection above, the reference Yao teaches ([0063]) that calendaring a battery structure such as an electrode enables a desired thickness and porosity of the structure to be achieved. Thus it would have been obvious to modify the method of modified Cook with the teachings of Yao such that the method further comprises a step of calendaring the precursor in order to produce the precursor sheet in order to reap these benefits.
Applicant argues on p. 5 of Remarks that Cook merely discusses that the thickness of the manufactured permeable top electrode may be approximately 1 µm, and that in addition, the permeable top electrode of Cook has a structure in which increasing the thickness is difficult, as the substance to be measured via the sensor must permeate through the porous structure of said top electrode. Thus, a person of ordinary skill in the art would lack any motivation to perform a modification that increases the thickness of the top electrode disclosed in Cook by 80 times or more.
This argument is not persuasive. Firstly, while Cook does appear to disclose ([0031]) an example of the top electrode having a thickness of approximately 1 µm, Cook does not appear to provide any other guidance regarding acceptable thicknesses of the top electrode, and thus it can be understood that Cook does not discourage or teach away from any other thicknesses such as the claimed 20 to 80 µm thickness. Secondly, Applicant’s statement that “the permeable top electrode of Cook has a structure in which increasing the thickness is difficult, as the substance to be measured via the sensor must permeate through the porous structure of said top electrode” appears to be a conclusory statement without any supporting evidence (see MPEP § 716.01(c)), as Cook does not appear to disclose any such relationship between thickness and performance. Finally, as set forth in detail in the rejection above, a person of ordinary skill in the art would have been motivated to modify the thickness of the precursor sheet of modified Cook such that it overlapped with the claimed thickness range, thus establishing a prima facie case of obviousness, in view of the combined teachings of Cook and Park.
Conclusion
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/J.M.F./Examiner, Art Unit 1725
/BASIA A RIDLEY/Supervisory Patent Examiner, Art Unit 1725
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