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 .
Summary
The Applicant’s arguments and claim amendments received December 15, 2025 have been entered into the file. Currently, claims 1, 3-6, 11-13, 16, and 20 have been amended, resulting in claims 1-20 pending for examination.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on December 16, 2025 has been considered by the examiner. Additionally, the IDS submitted on February 9, 2023 has been reconsidered in light of the Applicant’s filing of an English translation of foreign reference WO-2021088168 on December 15, 2025.
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.
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 1-2, 4-7, 9, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A).
Regarding claims 1, 4-5, and 7, Sha teaches an electrode sheet, which includes a current collector and a thin film (¶ [0030], Ln. 1-2). The electrode sheet further includes an electrode active material layer disposed between the current collector and the film (¶ [0031], Ln. 1-3). The film includes functional material particles, conductive agent particles, and a binder (¶ [0006], Ln. 1-4). Sha teaches that the functional particles include active ion supplements (¶ [0052], Ln. 3), and specifically can play the role of a lithium supplement (¶ [0053], Ln. 1-6). Sha provides examples of lithium-rich metal oxides including Li6CoO4 and Li5FeO4 (positive electrode lithium supplementing material with a gram capacity of ≥500 mAh/g) (¶ [0053], Ln. 9-12). Additionally, Sha teaches that the binder may be a chain polymer adhesive including one or more monomers selected from a list including polyacrylic acid and polyacrylates (¶ [0051], Ln. 1-8). The lithium-supplementing film of Example 3 includes Li6CoO4 as a lithium-supplementing agent, PTFE as a binder, and Ketjen black as a conductive agent (¶ [0112], Ln. 1-4).
Sha further teaches that the active material layer includes a positive electrode active material, a binder, and a conductive agent (¶ [0085], Ln. 5-7, 15-17, 27). Sha teaches that the binder is not limited and may include PVDF or PTFE (¶ [0085], Ln. 28-31).
Sha does not expressly teach an embodiment in which the binder included in the thin film is selected from polymers containing a first monomer unit represented by claimed formula I and a second monomer unit represented by claimed formula II or in which the binder included in the positive electrode active material layer includes PVDF or PTFE and a second binder including a polymer consisting of a monomer represented by formula III and a monomer represented by formula IV.
Koichiro teaches a binder composition for lithium secondary batteries with excellent binding ability, binding durability, that is chemically stable, and has excellent battery characteristics (¶ [0007], Ln. 1-3). Specifically, Koichiro teaches that the binder uses an acidic monomer in combination with a monomer copolymerizable with the acidic monomer, stating that an ethylenically unsaturated carboxylic acid monomer and an ethylenically unsaturated carboxylic acid ester monomer are preferred (¶ [0011], Ln. 1-9). For examples of ethylenically unsaturated carboxylic acid monomers, Koichiro teaches that unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid are preferred (¶ [0012], Ln. 6-8). For examples of monomers copolymerizable with such acidic monomers, Koichiro teaches that the preferred ethylenically unsaturated carboxylic acid ester monomers are alkyl (meth)acrylates (¶ [0013], Ln. 20-21). Koichiro teaches that a binder produced using this composition exhibits excellent binding between active materials and between the active material and the current collector, excellent binding durability, and excellent battery characteristics such as high capacity (¶ [0008], Ln. 4-6).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the binder included in the thin film of Example 3 of Sha to include a copolymer including polyacrylic acid (represented by claimed formulas I and S1) and poly(butyl acrylate) (represented by claimed formulas II and S8) based on the teachings of Koichiro. One of ordinary skill in the art would be motivated to include a copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates such as poly(butyl acrylate) based on the teaching of Koichiro that the composition exhibits excellent binding between active materials and between the active material and the current collector, excellent binding durability, and excellent battery characteristics such as high capacity. Further one of ordinary skill in the art would expect success with this composition based on the teaching of Sha that that the binder may be a chain polymer adhesive including one or more monomers selected from a list including polyacrylic acid and polyacrylates (¶ [0051], Ln. 1-8).
Further, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the positive electrode active material layer binder of Sha to include a copolymer including polyacrylic acid or poly(methacrylic acid) (represented by claimed formula III) and an alkyl (meth)acrylate such as poly(methyl methacrylate), poly(ethyl methacrylate), or poly (butyl acrylate) (represented by claimed formula IV), in addition to the PVDF or PTFE, based on the teachings of Koichiro. One of ordinary skill in the art would be motivated to include a copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid or poly(methacrylic acid) and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates based on the teaching of Koichiro that the composition exhibits excellent binding between active materials and between the active material and the current collector, excellent binding durability, and excellent battery characteristics such as high capacity.
Sha in view of Koichiro do not expressly teach that the molecular weight of the copolymer included in the thin film is 30,000 to 600,000 or that the molecular weight of the copolymer including polyacrylic acid or poly(methacrylic acid) (represented by claimed formula III) and an alkyl (meth)acrylate such as poly(methyl methacrylate), poly(ethyl methacrylate), or poly(butyl acrylate) (represented by claimed formula IV) included positive electrode active material is 50-5,000.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to try molecular weights of the binders within the claimed ranges of 30,000 to 600,000 for the copolymer included thin film and 50-5,000 for the copolymer included positive electrode active material. One of ordinary skill in the art would recognize that the molecular weight of the binder is largely dependent on the degree of polymerization of the monomers. Additionally, one of ordinary skill in the art would recognize that polymers with higher molecular weight typically have high adhesion and cycle life, however higher molecular weights also contribute to lower conductivity and high viscosity. Therefore, it would be obvious to try a range of molecular weights ranging from lower molecular weights to higher molecular weights (MPEP 2143 (I)(E)).
Regarding claim 2, Sha in view of Koichiro teaches all of the limitations of claim 1 above. Koichiro further teaches that the weight ratio of the acidic monomer to the monomer copolymerizable with the acidic monomer to the total amount of monomers used is 0.1:99.9 to 50:50, and is preferably 1:99 to 40:60 (¶ [0014], Ln. 1-3). Koichiro teaches that including the monomers within this range provides good binding properties and long-lasting binding properties (¶ [0014], Ln. 4).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to include a copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid in a weight percent of 1-40%, and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates such as poly(butyl acrylate) in a weight percent of 60-99% based on the teachings of Koichiro. One of ordinary skill in the art would be motivated to include the monomers within this range in order to provide good binding properties and long-lasting binding properties. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)).
Regarding claim 6, Sha in view of Koichiro teaches all of the limitations of claim 1 above and Sha further teaches the use of Li6CoO4 in Example 3. Although Sha does not expressly teach that the pH of Li6CoO4 is ≤13, the property is inherent to a Li6CoO4 solution prepared and tested under the claimed conditions. As Li6CoO4 is the lithium supplementing material taught by Sha and is also taught in the instant specification, the pH of a Li6CoO4 solution tested using this procedure would be within the claimed range of ≤13.
Regarding claim 9, Sha in view of Koichiro teaches all of the limitations of claim 1 above and Sha further teaches that the D50 particle size of the lithium supplement is within the range of 2-30 µm, overlapping the claimed range of 5-25 µm (¶ [0055], Ln. 9-10). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)).
Regarding claim 20, Sha in view of Koichiro teaches a positive electrode plate meeting all of the limitations of claim 1 above and Sha further teaches a secondary battery in Example 3 including an electrolyte solution that includes a 1 mol/L solution of LiPF6 (lithium hexafluorophosphate) in EC/DEC (¶ [0118], Ln. 1-3).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) as applied to claim 1 above, and further in view of Kawasaki, et al. (US 2021/0057721 A1).
Regarding claim 3, Sha in view of Koichiro teaches all of the limitations of claim 1 above. Sha in view of Koichiro do not expressly teach that the molecular weight of the copolymer including polyacrylic acid and an alkyl (meth)acrylate included in the thin film is 100,000 to 300,000.
Kawasaki teaches a lithium ion battery including polyacrylic acid in the binder (¶ [0070], Ln. 1-4). Kawasaki teaches that when polyacrylic acid is included in the binder, the molecular weight is preferably 300,000-350,000, teaching that within this range good dispersibility of the active material and the conductive assistant agent can be maintained and excessive increase in slurry viscosity can be suppressed (¶ [0077], Ln. 1-9).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the molecular weight of the copolymer including polyacrylic acid and an alkyl (meth)acrylate, as one of ordinary skill in the art would recognize that the molecular weight of the binder is largely dependent on the degree of polymerization of the monomers. Additionally, one of ordinary skill in the art would recognize that polymers with higher molecular weight typically have high adhesion and cycle life, however higher molecular weights also contribute to lower conductivity and high viscosity. Based on the teachings of Kawasaki, one of ordinary skill in the art would be motivated to include a binder that includes polyacrylic acid with a molecular weight of 300,000 in order to maintain good dispersibility of the functional material particles and the conductive agent particles, while suppressing excessive increase in slurry viscosity.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) as applied to claim 1 above, and further in view of Wang, et al. (High-Voltage “Single-Crystal” Cathode Materials for Lithium-Ion Batteries. Energy&Fuels, Vol 35 (Jan. 14, 2021), pp. 1918-1932).
Regarding claim 8, Sha in view of Koichiro teaches all of the limitations of claim 1 above. Sha in view of Koichiro do not expressly teach that the lithium supplementing material comprises monocrystal particles, and a number proportion of the monocrystal particles in the lithium supplementing material is 60-100%.
Wang teaches that the nanostructure of cathode materials in lithium-ion batteries impact the electrochemical performance, and that single-crystal cathodes result in superior electrochemical performance and are more practically available (Introduction, ¶ [0003], Ln. 1-6). Wang also teaches that lithium cobalt oxide is usually in the form of a SCC (Introduction, ¶ [0003], Ln. 8). Wang teaches that SCCs have advantages in mechanical strength, structure stability, long cycling performance, and thermal stability (Advantages of “Single-Crystal” Cathodes, ¶ [0001], Ln. 1-4).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the Li6CoO4 lithium supplementing material of Sha in view of Koichiro to have a single-crystal structure based on the teachings of Wang. One of ordinary skill in the art would recognize that the advantages of a single-crystal cathode taught by Wang would be advantageous to the lithium-supplementing film on the cathode of Sha in view of Koichiro. One of ordinary skill in the art would be motivated to include Li6CoO4 with a single-crystal structure such that 60-100% of the particles are single crystals, within the claimed range, in order to improve mechanical strength, structure stability, long cycling performance, and thermal stability of the lithium-supplementing film.
Claims 10 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) as applied to claim 1 above, and further in view of Tian, et al. (CN 112259803 A), cited on IDS.
Regarding claim 10, Sha in view of Koichiro teaches all of the limitations of claim 1 above. Sha in view of Koichiro do not expressly teach that the weight proportion of the positive electrode lithium supplementing material in the lithium supplementing film is 90-97%, that the weight proportion of the binder is 2-7%, or that the weight proportion of the conductive agent is 1-3%.
Tian teaches a lithium ion battery with a lithium ion stacked core comprising positive electrode sheets and negative electrode sheets wherein a lithium replenishing layer is provided on a surface of the positive electrode active material layer (¶ [0008]-[0009]). Tian teaches that the lithium replenishing layer includes a lithium-rich compound (¶ [0010], Ln. 1). The lithium replenishing layer further includes a conductive agent and a binder (¶ [0022], Ln. 1-2). The mass of the lithium-rich compound is 50-99% of the mass of the lithium replenishing layer (¶ [0017], Ln. 1-3). Tian specifically teaches that the lithium replenishing layer of the first embodiment is prepared using 98 parts by weight of the lithium-rich compound, 1 part by weight of binder, and 1 part by weight of conductive carbon black (¶ [0052], Ln. 4-7). Tian teaches that lithium replenishment solves the problem of low first efficiency (¶ [0005], Ln. 1-2).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the lithium supplementing film of Sha in view of Koichiro to include a weight percent of Li6CoO4 based on the teachings of Tian. One of ordinary skill in the art would recognize that a higher content of the lithium rich metal oxide would be capable of supplying more lithium ions during the batteries charging and discharging cycles. Based on the teachings of Tian, one of ordinary skill in the art would be motivated to include Li6CoO4 in a content of 50-99% in order to solve the problem of low first efficiency. More specifically, one would be motivated to include 98% Li6CoO4, 1% binder, and 1% conductive agent based on the total weight of the lithium supplementing film, based on the teachings of Tian.
Regarding claim 19, Sha in view of Koichiro teaches all of the limitations of claim 1 above. Sha further teaches that the thickness of the lithium supplementing film of Example 3 is 30 µm (¶ [0115], Ln. 10-12). Sha in view of Koichiro do not expressly teach that the thickness of the lithium supplementing film based on the total thickness of the lithium supplementing film and positive electrode active material layer is 3-22%, and optionally 8-15%.
Tian teaches that the thickness of the lithium replenishing layer is at least 5 µm so that the positive electrode sheet does not curl or break (¶ [0016], Ln. 5-8). Specifically, Tian teaches a positive electrode layer with a thickness of 150 µm and a lithium replenishing layer of 20 µm (¶ [0053], Ln. 1-5), resulting in a thickness of the lithium replenishing layer of 12% based on the total thickness of the lithium replenishing layer and positive electrode active material layer.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the thickness of the positive electrode active material layer and lithium supplementing film of Sha in view of Koichiro such that the thickness of the lithium supplementing film is 12%, within the claimed range of 3-22% and optionally 8-15%, based on the total thickness of the lithium supplementing film and positive electrode active material layer, based on the teachings of Tian. One would be motivated to modify the thicknesses to prevent the positive electrode sheet from curling or breaking.
Claims 11-12, 14, and 16-17 are rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) as applied to claim 1 above, and further in view of Bizet, et al. (US 2018/0355206 A1).
Regarding claim 11, Sha in view of Koichiro teaches all of the limitations of claim 1 above and as Sha in view of Koichiro teach including a copolymer included in the binder of the positive electrode including polyacrylic acid or poly(methacrylic acid) and an alkyl (meth)acrylate such as poly(methyl methacrylate), poly(ethyl methacrylate), or poly(butyl acrylate) in addition to the PVDF or PTFE, the combination of references teaches the inclusion of a monomer unit represented by claimed formulas S1 or S2 (polyacrylic acid or poly(methacrylic acid)) and a monomer unit represented by S4, S6, or S8 (poly(methyl methacrylate), poly(ethyl methacrylate), or poly(butyl acrylate)). Sha in view of Koichiro does not expressly teach that the content of the copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid or poly(methacrylic acid) and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates is 5-20% based on the total weight of the copolymer and PVDF or PTFE.
Bizet teaches a binder for a lithium-ion battery including at least one vinylidene fluoride polymer and at least one acrylic copolymer of methyl methacrylate and methacrylic acid (¶ [0020], Ln. 1-6). Bizet teaches that the content of the acrylic copolymer is, in particular, within 2.5-25% (¶ [0039], Ln. 4-7), specifically teaching examples of binder including PVDF and a copolymer of methyl methacrylate and methacrylic acid in ratios of 80:20 and 90:10 (Table 1, Examples 1 and 2). Bizet teaches that a binder with this composition has good adhesion of the active substance to a metal sheet and that the presence of the acrylic copolymer facilitates the application of the active substance during the manufacture of the electrode (¶ [0022]-[0023]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the binder of Sha in view of Koichiro to include PVDF in a content of 80-90% based on a total weight of the binder and the acrylic copolymer in a content of 10-20% based on the teachings of Bizet. One of ordinary skill in the art would be motivated to include the acrylic copolymer in a content of 10-20% in order to improve adhesion and to facilitate the application of the active substance during the manufacture of the electrode.
Regarding claim 12, Sha in view of Koichiro teach all of the limitations of claim 1 above. Sha further teaches that the positive electrode active material in the positive electrode active material layer for a lithium-ion battery may be at least one of a lithium transition metal phosphate or lithium transition metal oxide (¶ [0085], Ln. 17-22), specifically teaching a nickel-cobalt-manganese positive electrode active material (layered lithium transition metal oxide) in the battery of Example 3 (¶ [0116], Ln. 1-2). Sha in view of Koichiro does not expressly teach that the content of the copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid or poly(methacrylic acid) and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates is 10-20% based on the total weight of the copolymer and PVDF or PTFE.
Bizet teaches a binder for a lithium-ion battery including at least one vinylidene fluoride polymer and at least one acrylic copolymer of methyl methacrylate and methacrylic acid (¶ [0020], Ln. 1-6). Bizet teaches that the content of the acrylic copolymer is, in particular, within 2.5-25% (¶ [0039], Ln. 4-7), specifically teaching examples of binder including PVDF and a copolymer of methyl methacrylate and methacrylic acid in ratios of 80:20 and 90:10 (Table 1, Examples 1 and 2). Bizet teaches that a binder with this composition has good adhesion of the active substance to a metal sheet and that the presence of the acrylic copolymer facilitates the application of the active substance during the manufacture of the electrode (¶ [0022]-[0023]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the binder of Sha in view of Koichiro to include PVDF in a content of 80-90% based on a total weight of the binder and the acrylic copolymer in a content of 10-20% based on the teachings of Bizet. One of ordinary skill in the art would be motivated to include the acrylic copolymer in a content of 10-20% in order to improve adhesion to facilitate the application of the active substance during the manufacture of the electrode.
Regarding claim 14, Sha in view of Koichiro and further in view of Bizet teach all of the limitations of claim 12 above. Sha in view of Koichiro and further in view of Bizet further teach that the acrylic copolymer added to the binder of the positive electrode active material layer includes a copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid or poly(methacrylic acid) (containing one or more of the third monomer units).
Regarding claim 16, Sha in view of Koichiro teach all of the limitations of claim 1 above. Sha further teaches that the positive electrode active material in the positive electrode active material layer for a lithium-ion battery may be at least one of a lithium transition metal phosphate or lithium transition metal oxide, providing specific examples of lithium transition metal phosphates including lithium iron phosphate, lithium manganese phosphate, lithium manganese iron phosphate, lithium vanadium phosphate, and lithium cobalt phosphate (polyanionic materials) (¶ [0085], Ln. 17-20). Sha in view of Koichiro does not expressly teach that the content of the copolymer including an ethylenically unsaturated carboxylic acid monomer such as polyacrylic acid or poly(methacrylic acid) and an ethylenically unsaturated carboxylic acid ester monomer including alkyl (meth)acrylates is 5-10% based on the total weight of the copolymer and PVDF or PTFE.
Bizet teaches a binder for a lithium-ion battery including at least one vinylidene fluoride polymer and at least one acrylic copolymer of methyl methacrylate and methacrylic acid (¶ [0020], Ln. 1-6). Bizet teaches that the content of the acrylic copolymer is, in particular, within 2.5-25% (¶ [0039], Ln. 4-7), specifically teaching examples of binder including PVDF and a copolymer of methyl methacrylate and methacrylic acid in ratios of 80:20 and 90:10 (Table 1, Examples 1 and 2). Bizet teaches that a binder with this composition has good adhesion of the active substance to a metal sheet and that the presence of the acrylic copolymer facilitates the application of the active substance during the manufacture of the electrode (¶ [0022]-[0023]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the binder of Sha in view of Koichiro to include PVDF in a content of 90% based on a total weight of the binder and the acrylic copolymer in a content of 10% based on the teachings of Bizet. One of ordinary skill in the art would be motivated to include the acrylic copolymer in a content of 10% in order to improve adhesion and to facilitate the application of the active substance during the manufacture of the electrode.
Sha in view of Koichiro and further in view of Bizet do not expressly teach that the weight-average molecular weight of the acrylic copolymer is 100-3,000.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to try molecular weights of the acrylic copolymer within the claimed range of 100-3,000. One of ordinary skill in the art would recognize that the molecular weight of the copolymer is largely dependent on the degree of polymerization of the monomers. Additionally, one of ordinary skill in the art would recognize that polymers with higher molecular weight typically have high adhesion and cycle life, however higher molecular weights also contribute to lower conductivity and high viscosity. Therefore, it would be obvious to try a range of molecular weights ranging from lower molecular weights to higher molecular weights (MPEP 2143 (I)(E)).
Regarding claim 17, Sha in view of Koichiro and further in view of Bizet teach all of the limitations of claim 16 above. As described above, Sha in view of Koichiro teaches including a copolymer including polyacrylic acid or poly(methacrylic acid) (represented by claimed formulas S1 and S2) and an alkyl (meth)acrylate such as poly(methyl methacrylate), poly(ethyl methacrylate), or poly(butyl acrylate) (represented by claimed formulas S4, S6, and S8, respectively), in addition to the PVDF or PTFE.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) and further in view of Bizet, et al. (US 2018/0355208 A1) as applied to claim 12 above, and further in view of Shibata, et al. (US 2024/0097135 A1).
Regarding claim 13, Sha in view of Koichiro and further in view of Bizet teach all of the limitations of claim 12 above. Sha in view of Koichiro and Bizet do not expressly teach that the molecular weight of the copolymer including an alkyl (meth)acrylate such as poly(methyl methacrylate), poly(ethyl methacrylate), or poly(butyl acrylate) included in the positive electrode binder is 1,000 to 3,000.
Shibata teaches a binder for a secondary battery electrode with a reduced slurry viscosity that brings about better binding ability (¶ [0012], Ln. 1-6). Shibata teaches that the binder includes block polymer A and block polymer B (¶ [0040], Ln. 1-6), teaching that preferred monomers of the monomer that makes up polymer block B are alkyl methacrylate ester compounds, such as methyl methacrylate and ethyl methacrylate (¶ [0069], Ln. 1-5, ¶ [0071], Ln. 1-3). Shibata teaches that the average molecular weight of the polymer block B ranges from 1,000-1,000,000, teaching that with a molecular weight of 1,000 or higher, the binding ability in the electrode is improved, and that lower molecular weights have better flowability and are easier to handle (¶ [0081], Ln. 1-10).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the molecular weight of the copolymer including an alkyl (meth)acrylate such as poly(methyl methacrylate) or poly(ethyl methacrylate), or poly(butyl acrylate), as one of ordinary skill in the art would recognize that the molecular weight of the binder is largely dependent on the degree of polymerization of the monomers. Additionally, one of ordinary skill in the art would recognize that polymers with higher molecular weight typically have high adhesion and cycle life, however higher molecular weights also contribute to lower conductivity and high viscosity. Based on the teachings of Shibata, one of ordinary skill in the art would be motivated to modify the copolymer including an alkyl methacrylate ester compound to have a molecular weight of 1,000 or higher, such as 1,000-3,000, in order to improve the binding ability in the electrode while being low enough to ensure good flowability.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) and further in view of Bizet, et al. (US 2018/0355208 A1) as applied to claim 12 above, and further in view of Chen, et al. (US 2023/0299281 A1).
Regarding claim 15, Sha in view of Koichiro and further in view of Bizet teach all of the limitations of claim 12 above and Sha further teaches that the D50 particle size of the electrode active material particles may be 1-20 μm (¶ [0061], Ln. 6-8), overlapping the claimed range of 2-10 µm. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)). Sha in view of Koichiro and further in view of Bizet do not expressly teach that the compacted density of the positive electrode active material layer is 3.5-3.8 g/cm3.
Chen teaches a composite positive electrode material including a ternary material (¶ [0053], Ln. 1-3). The ternary material is a lithium nickel cobalt material (¶ [0055], Ln. 1-7). Chen further teaches that the positive electrode plate has a high compacted density, ensuring the energy density of the battery. The electrode compacted density of the plate having the ternary material is generally above 3.0 g/cm3 and Chen teaches that due to the possibility of material crushing, the electrode compacted density does not exceed 3.8 g/cm3 (¶ [0120], Ln. 1-6). Specifically, Chen teaches examples of NCM electrode materials with compacted density of 3.62 g/cm3 (Table 1, Experiment 4).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the compacted density of the positive electrode active material layer of Sha to be within 3.0-3.8 g/cm3, such as 3.62 g/cm3, based on the teachings of Chen. One of ordinary skill in the art would be motivated to have a high compacted density for a NCM positive electrode to ensure the energy density. Further one would be motivated to keep the compacted density of the NCM positive electrode below 3.8 g/cm3 in order to avoid material crushing.
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) and further in view of Bizet, et al. (US 2018/0355208 A1) as applied to claim 16 above, and further in view of Chen, et al. (Effects of Particle Size Distribution on Compacted Density of Lithium Iron Phosphate 18650 Battery. Journal of Electrochemical Energy Conversion and Storage, Vol. 15 Issue 4 (Nov. 2018), pp. 041011-1 – 5), hereinafter “Lei Chen.”
Regarding claim 18, Sha in view of Koichiro and further in view of Bizet teach all of the limitations of claim 16 above. Sha in view of Koichiro and further in view of Bizet do not expressly teach that the compacted density of the positive electrode active material layer is 2.4-2.7 g/cm3 or that the D50 particle size of the positive electrode active material is 0.2-1.5 µm.
Lei Chen teaches the use of lithium iron phosphate (LFP) as a lithium-ion battery cathode material due to its low price, high theoretical capacity, stable operating voltage, safety, stability, and cycle life (Introduction, ¶ [0002], Ln. 1-5). Lei Chen teaches that LFP particles with a small particle size means small diffusion length and large surface reaction sites for lithium ions, improving the lithium-ion intercalation kinetics (Results and Discussion, ¶ [0001], Ln. 15-18). Specifically, Lei Chen teaches examples including LFP-3 with a D50 particle size of 1.46 µm LFP-4 with a D50 particle size of 1.02 µm (Table 1). Lei Chen further teaches that the compacted density of LFP-3 and LFP-4 range from 2.38-2.52 g/cm3 and 2.32-2.47 g/cm3, respectively (Table 5). Lei Chen teaches that it is advantageous to prepare electrodes with high compaction density as it results in larger volumetric capacity (Results and Discussion, ¶ [0004], Ln. 4-6, 15-16, 20-21).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the lithium iron phosphate positive electrode active material of Sha to have a small particle size such as 1.46 or 1.02 µm, allowing for a high compaction density ranging from 2.38-2.52 g/cm3 and 2.32-2.47 g/cm3, respectively, overlapping the claimed ranges. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)). One of ordinary skill in the art would be motivated to modify the lithium iron phosphate positive electrode active material of Sha in order to improve the lithium-ion intercalation kinetics and improve volumetric capacity.
Response to Arguments
Response-Claim Objections
The previous objection to claim 4 for minor informalities is overcome by the Applicant’s amendment to the claim in the response filed December 15, 2025.
Response-Claim Rejections – 35 U.S.C. 112
The previous rejections of claims 5-6 and 20 as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention are overcome by the Applicant’s amendments to claims 5-6 and 20 in the response filed December 15, 2025.
Response-Claim Rejections – 35 U.S.C. 103
In light of the Applicant’s amendment to claim 1 to incorporate limitations of claims 3 and 11, the previous rejections of record under 35 U.S.C. 103 over Sha, et al. (WO 2022/012357 A1) in view of Koichiro, et al. (JPH 11-149929 A) are modified to address the added limitations and the references are used in the rejections above.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SARAH J JACOBSON whose telephone number is (703)756-1647. The examiner can normally be reached Monday - Friday 8:00am - 5:00pm.
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, Mark Ruthkosky can be reached at (571) 272-1291.
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.
/SARAH J JACOBSON/Examiner, Art Unit 1785
/MARK RUTHKOSKY/Supervisory Patent Examiner, Art Unit 1785