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 .
Election/Restriction
Amended claim 21, in now requiring polyacrylamide (PAM) rather than fumaric acid, maleic acid, and/or citric acid, is directed to an invention that is independent or distinct from the invention originally claimed for the following reasons:
Claim 21 is drawn to a secondary battery including a negative electrode with organic binders A and B cross-linked with inorganic binder C, where organic binder B is PAM, classified in H01M 4/622.
Applicant has received an action on the merits for the originally presented invention of, inter alia, claim 21, drawn to an organic binder B of fumaric acid, maleic acid, and/or citric acid, classified in H01M 4/621.
The originally presented species, fumaric acid, maleic acid, and/or citric acid, are distinct from the species PAM because they are mutually exclusive (as implied at least in Table 1’s exs. including different embodiments of binder B—specifically citric acid in Ex. 10—which yield different performance results (Table 2)). Further, there is no evidence or admission of record showing PAM to be an obvious variant of the above species. Thus, an examination burden is present because prior art relevant to fumaric acid, maleic acid, and/or citric acid may not necessarily be relevant to PAM.
Because applicant has received an action on the merits for the originally presented invention, this invention has been constructively elected by original presentation for prosecution on the merits. Accordingly, claim 21 is withdrawn from consideration as being directed to a non-elected invention. See 37 CFR 1.142(b) and MPEP 821.03.
To preserve a right to petition, the reply to this action must distinctly and specifically point out supposed errors in the restriction requirement. Otherwise, the election shall be treated as a final election without traverse. Traversal must be timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are subsequently added, applicant must indicate which of the subsequently added claims are readable upon the elected invention.
Should applicant traverse on the ground that the inventions are not patentably distinct, applicant should submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. In either instance, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention.
Status of Claims
Applicant’s amendment and arguments, filed 10/20/2025, have been fully considered. Claim(s) 1, 7, 15, and 21 is/are amended; claim(s) 3–6, 11–14, 16, 18, and 22–25 stand(s) as originally or previously presented; claim(s) 2, 8–10, 17, 19, and 20 is/are canceled; and claim 26 is added without entering new matter. Additionally, as noted above, claim 21, in now being drawn to PAM, is withdrawn from consideration as being directed to a distinct, non-elected invention, pursuant to 37 CFR 1.142(b) and MPEP 821.03. Examiner affirms that the original disclosure provides adequate support for the amendment.
Upon considering said amendment and arguments, the previous 35 U.S.C. 112(b) rejection set forth in the Office Action mailed 08/18/2025 has/have been withdrawn. However, the pending 35 U.S.C. 103 rejection has been maintained and altered as necessitated by Applicant’s amendment.
Claim Rejections - 35 USC § 103
The text forming the basis for the rejection under 35 U.S.C. 103 may be found in a prior Office Action.
Claim(s) 1, 3–7, 11–14, 22, 23, 25, and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yushin et al. (US 20210313617 A1; EFD 04/03/20) (Yushin) in view of Kay (US 20110117432 A1) and Huang et al. (Partially Neutralized Polyacrylic Acid/Poly(vinyl alcohol) Blends as Effective Binders for High-Performance Silicon Anodes in Lithium Ion Batteries) (Huang).
Regarding claims 1, 3–7, 11, and 14, Yushin discloses an apparatus (e.g., EV, ¶ 0003) comprising a secondary battery (lithium battery, e.g., Title), comprising a negative electrode plate (anode, e.g., ¶ 0007), wherein the negative electrode plate comprises a negative-electrode active material (e.g., ¶ 0101, 0103) and a binder (e.g., ¶ 0102).
Yushin further discloses that the negative electrode may include a blend of intercalation-type active material such as natural graphite for higher electrode density and first-cycle coulombic efficiency (¶ 0058, 0086), as well as conversion-type active material such as Si-containing materials for higher gravimetric and volumetric capacity (¶ 0057, 0058), though Yushin fails to explicitly disclose an embodiment containing graphite.
Yushin is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery electrode active material and binders.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to routinely incorporate a blend of natural graphite and Si-containing materials as Yushin’s negative active material—so that the active material comprises graphite—with the reasonable expectation of providing higher electrode density first-cycle coulombic efficiency, and gravimetric and volumetric capacity, as suggested by Yushin.
Yushin further discloses several exemplary binders, including several water-soluble polymers such as polyacrylic acid (PAA), polyvinyl alcohol (PVA), alginate salts such as sodium alginate, and so on (¶ 0104, 0106), as well as a particular desire for water-soluble co-polymer binders (¶ 0106–0110), but fails to explicitly articulate such a co-polymer of at least two of the above-referenced polymers.
As Yushin recognizes polymers such as PAA and PVA as equivalent water-soluble binders, alongside the desire for a co-polymer, it would have been obvious to one of ordinary skill in the art, before the claimed invention’s effective filing date, to routinely incorporate a co-polymer of, e.g., PVA and PAA with a reasonable expectation of forming a successful co-polymer binder (MPEP 2144.06 (I) and 2143 (A.)).
Accordingly, Yushin would disclose a co-polymer of a first organic binder A with at least two hydroxyl groups (PVA) and a second organic binder B with at least two –C(O)R groups, where R represents –OX, where X is H (PAA).
Yushin further desires to cross-link such water-soluble binders to, e.g., reduce swelling (¶ 0107) but is silent to the cross-linker as well as fails to explicitly articulate a cross-linked embodiment of at least two of these polymers and, thus, fails to explicitly disclose the recited organic binders A and B in a cross-linked structure alongside an inorganic binder C.
Kay, in teaching inorganic binders for battery electrodes (Title), teaches an inorganic binder of preferably lithium phosphate (e.g., ¶ 0015). Kay teaches that the inorganic binder preferably combines with an organic polymer binder to form a protective coating on the active material’s surface and acts as primer binder to strongly attach the organic binder, which provides more flexible binding over larger distance (¶ 0020). Kay teaches that the inorganic binder preferably cross-links with water-soluble organic binders such as PVA and polyhydroxyl polymers to further reduce swelling as well as improve mechanical strength and chemical resistance (¶ 0021).
Kay is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery electrode binders.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to cross-link Yushin’s co-polymeric, water-soluble binder via an inorganic binder of lithium phosphate, as desired by Yushin and taught by Kay, with the reasonable expectation of providing more flexible binding over larger distance, further reducing swelling, as well as improving mechanical strength and chemical resistance, as taught by Kay.
Thus, modified Yushin would disclose an inorganic binder C of a phosphate (lithium phosphate from Kay); and the polymer comprises a first condensation unit between at least one of the at least two –C(O)R groups and at least one of the at least two hydroxyl groups (between binders A and B, as in instant specification, ¶ 0136), an inorganic polymerization unit (from phosphate binder C, as in instant spec.’s ¶ 0136), and a second condensation unit between the inorganic polymerization unit and at least one of the at least two –C(O)R groups (between binders C and B, as in instant spec.’s ¶ 0136), wherein the inorganic polymerization unit comprises a polyphosphate oxygen unit (by cross-linking with the phosphate, as in instant spec., e.g., ¶ 0136).
Modified Yushin, as noted above, generally discusses the benefits of the organic/inorganic binder, as well as the ability to employ a PVA:PAA copolymer (as binders A and B), but fails to explicitly articulate each binder’s weight ratio and, thus, based on a total weight of binders A–C, 10–49% organic binder A, 50–89% organic binder B, and 0.5–10% inorganic binder C.
Huang, in teaching cross-linked PVA-PAA blends for battery anodes (Abstract), teaches that a PAA:PVA ratio of 60:40, i.e., 1.5:1, exhibits the highest stiffness with optimal flexibility and displays the best electrochemical performance relative to similar ratios (e.g., p. 6892, right col., first para. under Results and Discussion).
Huang is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely PVA/PAA-based anode binders.
It would have been obvious to one of ordinary skill in the art, before the claimed invention's effective filing date, that, if selecting PVA-PAA as Yushin’s copolymer binder (binders A and B), these polymer units must necessarily be incorporated at some weight ratio, and, as demonstrated by Huang, the skilled artisan would find it obvious to employ, e.g., a 60:40 PAA:PVA ratio.
More importantly, though, Huang teaches that PAA is effective for Si-based electrodes due to H-bonding with Si, also displaying high capacity and long cyclability compared to traditional binders such as PVDF (p. 6890, right col., first full ¶). Huang further teaches that to improve PAA’s mechanical flexibility, PVA, which is nontoxic and mechanically robust, can connect to the PAA through H-bonding and cross-linking (p. 6891, left col., first ¶). One skilled in the art, meanwhile, would further recognize that the inorganic binder must necessarily be included at a content sufficient for Kay’s cross-linking and protective coating atop the active material’s surface without diminishing the other binders’ effects. To balance these effects, then, it would have been obvious to arrive at the respectively recited ranges by routinely optimizing the A:B:C binder ratio (MPEP 2144.05 (II)).
It is submitted that the above disclosure further reads on the following:
(claims 3 and 4) the first organic binder A comprises a side hydroxyl group represented by the first structure, where R1–R3 are each H, and is polyvinyl alcohol (Yushin’s PVA);
(claims 5 and 6) the second organic binder B comprises a structure segment represented by B1, where each of Ra–Rc is H, and is polyacrylic acid (Yushin’s PAA);
(claim 7) the phosphate is lithium phosphate (Kay’s lithium phosphate);
(claim 11) a weight ratio of the first organic binder A to the second organic binder B is 1:1.5 (per Huang), falling within 0.9:1–1:9.
Regarding claim 12, modified Yushin discloses the secondary battery according to claim 1.
Yushin further discloses that it may be advantageous to use elastic nanoparticles such as styrene-butadiene rubber (SBR) alongside the more brittle and/or water-soluble polymers to overcome their brittleness and allow utility with both small and large composite particles (¶ 0107) but fails to explicitly disclose an embodiment of such.
It would have been obvious to one of ordinary skill in the art, before the claimed invention’s effective filing date, to routinely incorporate SBR into modified Yushin’s binder composition with a reasonable expectation that such would overcome the water-soluble polymers’ brittleness and allow utility with both small and large composite particles, as suggested by Yushin (see also MPEP 2144.06 (I) and 2143 (A.)).
Regarding claims 13 and 25, modified Yushin discloses the secondary battery according to claim 12.
As noted in claim 1, Kay teaches that the cross-linked organic-inorganic binder provides more flexible binding over larger distance, reduces swelling, and improves mechanical strength and chemical resistance (¶ 0020 and 0021). Meanwhile, as further outlined above, Huang teaches that PVA and PAA work together to respectively provide mechanical flexibility alongside high capacity and long cyclability (see claim 1). Yushin further discloses that, depending on the type of active material, the content of the elastic nanoparticles such as SBR based on the total binder’s content may vary (see generally 5~70 wt%, 15~50 wt% in purely intercalation-type anodes, and 55~95 wt% in conversion-type anodes, ¶ 0106), where, again, the SBR overcomes the water-soluble polymers’ brittleness and enables utility with both small and large composite particles (¶ 0106).
Though modified Yushin fails to explicitly articulate the recited weight ratio of the binder composition to SBR, to balance the above effects, it would have been obvious to arrive at the recited ratio by routinely optimizing the binder composition:SBR ratio (MPEP 2144.05 (II)).
Regarding claim 22, modified Yushin discloses the secondary battery according to claim 1 but fails to explicitly articulate that inorganic binder C further comprises a borate and, thus, that the inorganic polymerization unit comprises a polyboroxide unit.
Kay further teaches that other materials such as borates may also be included alongside the phosphate binder for strong cohesion and adhesion to the electrode materials (¶ 0018).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to incorporate a borate—and, thus, polyboroxide polymerization unit (as implied in instant spec., e.g, ¶ 0136)—into modified Yushin’s cross-linked binder, as taught by Kay, with the reasonable expectation of further improving the binder’s cohesion and adhesion to the electrode materials, as taught by Kay.
Regarding claim 23, modified Yushin discloses the secondary battery according to claim 1, wherein the first organic binder A is polyvinyl alcohol (Yushin’s PVA), and the second organic binder B is polyacrylic acid (Yushin’s PAA).
Modified Yushin further discloses the inorganic binder C cross-linking the above binders (per Kay, from claim 1) but fails to explicitly articulate that inorganic binder C further comprises sodium silicate and, thus, that the inorganic polymerization unit comprises a polysiloxane unit.
Kay further teaches that other materials such as silicates may also be included alongside the phosphate binder for strong cohesion and adhesion to the electrode materials (¶ 0018). Kay teaches sodium as a suitable counterion for the silicate (e.g., claim 9).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to incorporate sodium silicate—and, thus, a polysiloxane polymerization unit (as implied in instant spec., e.g., ¶ 0136)—into modified Yushin’s cross-linked binder, as taught by Kay, with the reasonable expectation of further improving the binder’s cohesion and adhesion to the electrode materials, as taught by Kay.
Regarding claim 26, modified Yushin discloses the secondary battery according to claim 1.
As noted in claim 1’s PVA:PAA as binder A/B, Huang teaches that the 60:40 blend of PVA:PAA provides the greatest stiffness/flexibility and electrochemical performance, but, as seen in fig. 2, Huang tests other ratios and appears to achieve similar tensile strength/recovery at comparable ratios. Importantly, then, as discussed above, one skilled in the art would recognize that enough PAA must be present for suitable H-bonding to Si for high capacity and cyclability (Huang, p. 6890, right col., first full ¶), while enough PVA must be present for suitable mechanical strength and flexibility (Huang’s p. 6891, left col., first ¶). The skilled artisan would further understand, meanwhile, that any addition of Kay’s inorganic binder necessarily reduces the relative contents of PVA and PAA but that enough inorganic binder must be present for Kay’s protective coating atop the active material’s surface. To balance these effects, then, it would have been obvious to arrive at the recited range by routinely optimizing the A:B:C binder ratio, absent demonstrated criticality (MPEP 2144.05 (II)).
Claim(s) 15, 16, and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yushin et al. (US 20210313617 A1) (Yushin) in view of Kay (US 20110117432 A1), Huang et al. (Partially Neutralized Polyacrylic Acid/Poly(vinyl alcohol) Blends as Effective Binders for High-Performance Silicon Anodes in Lithium Ion Batteries) (Huang), and Choi et al. (US 20090136845 A1) (Choi).
Regarding claim 15, Yushin discloses a preparation method of a negative electrode plate, the method comprising: forming an initial negative-electrode film layer on a surface of a negative-electrode current collector (see anode of, e.g., ¶ 0007, which is producible via conventional electrode manufacturing method involving electrode-slurry casting on current collector foils, e.g., ¶ 0100), wherein the initial negative-electrode film layer comprises a negative-electrode active material (e.g., ¶ 0101, 0103) and a binder (in anode slurry, e.g., ¶ 0102).
Yushin further discloses that the negative electrode may include a blend of intercalation-type active material such as natural graphite for higher electrode density and first-cycle coulombic efficiency (¶ 0058, 0086), as well as conversion-type active material such as Si-containing materials for higher gravimetric and volumetric capacity (¶ 0057, 0058), though Yushin fails to explicitly disclose an embodiment containing graphite.
Yushin is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery electrode active material and binders.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to routinely incorporate a blend of natural graphite and Si-containing materials as Yushin’s negative active material—so that the active material comprises graphite—with the reasonable expectation of providing higher electrode density first-cycle coulombic efficiency, and gravimetric and volumetric capacity, as suggested by Yushin.
Yushin discloses several exemplary binders, including several water-soluble polymers such as polyacrylic acid (PAA), polyvinyl alcohol (PVA), alginate salts such as sodium alginate, and so on (¶ 0104, 0106), as well as a particular desire for water-soluble co-polymer binders (¶ 0106–0110), but fails to explicitly articulate such a co-polymer of at least two of the above-referenced polymers.
As Yushin recognizes polymers such as PAA and PVA as equivalent water-soluble binders, alongside the desire for a co-polymer, it would have been obvious to one of ordinary skill in the art, before the claimed invention’s effective filing date, to routinely incorporate a co-polymer of, e.g., PVA and PAA with a reasonable expectation of forming a successful co-polymer binder (MPEP 2144.06 (I) and 2143 (A.)).
Accordingly, Yushin would disclose a co-polymer of a first organic binder A with at least two hydroxyl groups (PVA) and a second organic binder B with at least two –C(O)R groups, where R represents –OX, and X is hydrogen (PAA).
Yushin further desires to cross-link such water-soluble binders to, e.g., reduce swelling (¶ 0107) but is silent to the cross-linker as well as fails to explicitly articulate a cross-linked embodiment of at least two of these polymers and, thus, fails to explicitly disclose the recited organic binders A and B in a cross-linked structure alongside an inorganic binder C.
Kay, in teaching inorganic binders for battery electrodes (Title), teaches an inorganic binder of preferably lithium phosphate (e.g., ¶ 0015). Kay teaches that the inorganic binder preferably combines with an organic polymer binder to form a protective coating on the active material’s surface and acts as primer binder to strongly attach the organic binder, which provides more flexible binding over larger distance (¶ 0020). Kay teaches that the inorganic binder preferably cross-links with water-soluble organic binders such as PVA and polyhydroxyl polymers to further reduce swelling as well as improve mechanical strength and chemical resistance (¶ 0021).
Kay is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery electrode binders.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to cross-link Yushin’s co-polymeric, water-soluble binder via an inorganic binder of lithium phosphate, as taught by Kay, with the reasonable expectation of providing more flexible binding over larger distance, further reducing swelling, as well as improving mechanical strength and chemical resistance, as taught by Kay.
Thus, modified Yushin would disclose an inorganic binder C of a phosphate (lithium phosphate from Kay) and, thus, that the negative-electrode film layer—formed after Yushin’s process of casting and calandering, ¶ 0100—comprises a polymer obtained by crosslinking (via Kay), and the polymer comprises a first condensation unit between at least one of the at least two –C(O)R groups and at least one of the at least two hydroxyl groups (between binders A and B, as in instant specification, ¶ 0136), an inorganic polymerization unit (from phosphate binder C, as in instant spec., ¶ 0136), and a second condensation unit between the inorganic polymerization unit and at least one of the at least two –C(O)R groups (between binders C and B, as in instant spec., ¶ 0136), wherein the inorganic polymerization unit comprises a polyphosphate oxygen unit (by cross-linking with the phosphate, as in instant spec., e.g., ¶ 0136).
Modified Yushin, as noted above, generally discusses the benefits of the organic/inorganic binder, as well as the ability to employ a PVA:PAA copolymer (as binders A and B), but fails to explicitly articulate each binder’s weight ratio and, thus, based on a total weight of binders A–C, 10–49% organic binder A, 50–89% organic binder B, and 0.5–10% inorganic binder C.
Huang, in teaching cross-linked PVA-PAA blends for battery anodes (Abstract), teaches that a PAA:PVA ratio of 60:40, i.e., 1.5:1, exhibits the highest stiffness with optimal flexibility and displays the best electrochemical performance relative to similar ratios (e.g., p. 6892, right col., first para. under Results and Discussion).
Huang is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely PVA/PAA-based anode binders.
It would have been obvious to one of ordinary skill in the art, before the claimed invention's effective filing date, that, if selecting PVA-PAA as Yushin’s copolymer binder (binders A and B), these polymer units must necessarily be incorporated at some weight ratio, and, as demonstrated by uang, the skilled artisan would find it obvious to employ, e.g., a 60:40 PAA:PVA ratio.
More importantly, though, Huang teaches that PAA is effective for Si-based electrodes due to H-bonding with Si, also displaying high capacity and long cyclability compared to traditional binders such as PVDF (p. 6890, right col., first full ¶). Huang further teaches that to improve PAA’s mechanical flexibility, PVA, which is nontoxic and mechanically robust, can connect to the PAA through H-bonding and cross-linking (p. 6891, left col., first ¶). One skilled in the art, meanwhile, would further recognize that the inorganic binder must necessarily be included at a content sufficient for Kay’s cross-linking and protective coating atop the active material’s surface without diminishing the other binders’ effects. To balance these effects, then, it would have been obvious to arrive at the respectively recited ranges by routinely optimizing the A:B:C binder ratio (MPEP 2144.05 (II)).
Yushin further discloses that such cross-linking may occur after casting the slurry onto the electrode (¶ 0107), as well as that that the slurry may be dried after casting (¶ 0045), and Kay further teaches that a condensate of lithium polyphosphate forms upon heating above 150°C (¶ 0015); yet, in being unconcerned with the specifics of such a cross-linking reaction, modified Yushin fails to explicitly articulate triggering a crosslinking reaction between the first organic binder A, the second organic binder B, and the inorganic binder C in the initial negative-electrode film layer at a temperature of at least 150°C to form the negative-electrode film layer, so as to obtain the negative electrode plate.
Choi, in teaching a negative electrode binder formed by cross-linking a first hydroxyl- or amino-functionalized polymer with a second carboxylated polymer (Abstract), teaches, after coating the electrode slurry onto the collector and evaporating the solvent, performing a second heat treatment at 150–200°C (¶ 0087). Choi teaches that this range drives sufficient condensation reactions while preventing the binder’s decomposition (¶ 0087).
Choi is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery anode binders.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, that Yushin’s slurry drying must necessarily be performed at some temperature, and, as demonstrated by Choi, the skilled artisan would find it obvious to perform Choi’s second heat treatment/elevated drying at 150–200°C with the reasonable expectation of driving sufficient condensation reactions while preventing the binder’s decomposition, as taught by Choi.
Regarding claim 16, modified Yushin discloses the preparation method according to claim 15, wherein forming the initial negative-electrode film layer on the surface of the negative-electrode current collector comprises: dispersing a negative-electrode active material, a conductive agent, the first organic binder A, the second organic binder B, and the inorganic binder C in a solvent to prepare a negative electrode slurry (mixing anode active material, conductive additive, and binder(s)—and, thus, modified Yushin’s cross-linked binder structure—in solvent in substantially liquid phase in Yushin, e.g., ¶ 0045 or 0100, which the skilled artisan would appreciate would constitute dispersing versus complete solvation, as in instant spec.’s ¶ 0127); and applying the negative electrode slurry on the surface of the negative-electrode current collector, followed by drying at the temperature of 150–200°C to trigger the crosslinking reaction—satisfying at least 150°C—to form the initial negative-electrode film layer (drying in Yushin’s ¶ 0100/second heat treatment from Choi’s ¶ 0087).
Regarding claim 18, modified Yushin discloses the preparation method according to claim 15.
Yushin further discloses that it may be advantageous to use elastic nanoparticles such as styrene-butadiene rubber (SBR) alongside the more brittle and/or water-soluble polymers to overcome their brittleness and allow utility with both small and large composite particles (¶ 0107) but fails to explicitly disclose an embodiment of such.
It would have been obvious to one of ordinary skill in the art, before the claimed invention’s effective filing date, to routinely incorporate SBR into modified Yushin’s binder composition—and, thus, mix the SBR into the initial film layer, i.e., slurry pre-drying and cross-linking—with a reasonable expectation that such would overcome the water-soluble polymers’ brittleness and allow utility with both small and large composite particles, as suggested by Yushin (MPEP 2144.06 (I) and 2143 (A.)).
Claim(s) 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yushin et al. (US 20210313617 A1) (Yushin) in view of Kay (US 20110117432 A1) and Huang et al. (Partially Neutralized Polyacrylic Acid/Poly(vinyl alcohol) Blends as Effective Binders for High-Performance Silicon Anodes in Lithium Ion Batteries) (Huang), as applied to claim 4, further in view of Bae et al. (US 20190067699 A1) and Park et al. (US 20150243997 A1) (Park).
Regarding claim 24, modified Yushin discloses the secondary battery according to claim 4, wherein the second organic binder B is polyacrylic acid (Yushin’s PAA, per claim 1).
However, in being unconcerned with PVA and PAA’s molecular weights, modified Yushin fails to explicitly disclose a weight-average molecular weight of 1) 16,000–67,000 g/mol and 2) 2,000–450,000 g/mol, respectively.
Regarding 1), Bae, in teaching an electrode binder that may comprise PVA (Abstract), teaches that PVA may exhibit a weight-average molecular weight of 10,000~500,000 Da, i.e., 10,000~500,000 g/mol, because this range improves the electrode’s physical properties (¶ 0093).
Bae is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery binders.
It would have been obvious to one of ordinary skill in the art, before the claimed invention's effective filing date, that Yushin’s PVA must necessarily be incorporated with some molecular weight, and, as demonstrated by Bae, the skilled artisan would find it obvious to employ a weight-average molecular weight of 10,000~500,000 g/mol as an appropriate weight. This range overlaps the recited range such that the skilled artisan could have routinely selected within the overlap with a reasonable expectation of forming a successful PVA binder with suitable physical properties (MPEP 2144.05 (I)).
Regarding 2), Park, in teaching a battery negative electrode (Abstract), teaches a polyacrylate binder with a weight-average molecular weight of 450,000 Da (¶ 0120–0123), i.e., 450,000 g/mol.
Park is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely battery binders.
It would have been obvious to one of ordinary skill in the art, before the claimed invention's effective filing date, that Yushin's PAA must necessarily be incorporated with some molecular weight, and, as demonstrated by Park, the skilled artisan would find it obvious to employ a weight-average molecular weight of 450,000 g/mol as an appropriate weight, which satisfies 2,000–450,000 g/mol.
Regarding the molecular weights of sodium carboxymethyl cellulose, sodium alginate, and polyacrylamide, Examiner notes that such are directed to alternative options of parent claim 4 as well as claim 24 and, thus, not positively required by the claim. Claim 4 recites that “the first organic binder A is selected from one or more of polyvinyl alcohol, sodium carboxymethyl cellulose, polyethylene oxide, and polyethylene glycol”, while claim 24 recites that “the second organic binder B is selected from one or more of polyacrylic acid, polyacrylamide, fumaric acid, maleic acid, citric acid, and sodium alginate”, and, therefore, the remaining compounds’ molecular weights are reasonably considered optional, alternative limitations depending on selecting sodium carboxymethyl cellulose, sodium alginate, and polyacrylamide in claim 4/24, which, in this case, are unselected because Yushin discloses PVA and PAA, as established in claims 1 and 4.
Response to Arguments
Applicant’s arguments with respect to claims 1, 15, 21, and 26 have been fully considered but are unpersuasive.
Applicant argues that Kay fails to teach using the inorganic binder with graphite. Examiner respectfully notes that 1) Kay is not used to teach this feature, as Yushin discloses or renders obvious a graphite-Si blend, and 2) as Applicant notes, Kay teaches utility with carbonaceous anode materials, of which graphite is the most common. Although Applicant further argues that Kay fails to disclose the A:B:C ratio, Examiner respectfully reiterates the rationale from claim 1, where the skilled artisan would recognize that each of the binders must necessarily be present in an amount to perform its respective function without compromising the other binders’ effects, and, thus, in accounting for each binder’s effects, it appears that the skilled artisan would have routinely optimized the A:B:C ratio based on MPEP 2144.05 (II) (see also MPEP 2145 (IV) for lack of persuasiveness in attacking references individually when the rejection is based on the combination of references).
Applicant further argues that Huang fails to teach the inorganic binder, and neither Yushin nor Huang teaches or discloses the claimed, cross-linked polymer. Again, Examiner respectfully submits that Huang was only used to teach the ratio of binders A and B, and Yushin’s general disclosure of cross-linked organic polymers was modified with Kay’s inorganic, cross-linking binder to achieve claim 1’s binder. Regarding Applicant’s auxiliary argument that Huang only relates to Si anodes versus the claimed graphite active material, Examiner respectfully echoes that Yushin renders obvious a graphite-Si mixture as well as the ability to select a PVA:PAA copolymer. As each component of the copolymer must necessarily exist at some concentration, it appears that the skilled artisan would have consulted Huang’s ratio for the benefits discussed in claim 1, both in relation to H-bonding with Si materials as well as general mechanical strength and flexibility.
Applicant next argues that it is hindsight to assert that the skilled artisan would routinely optimize A:B:C because none of Yushin, Kay, or Huang specifies this ratio or identifies these contents as result-effective. Examiner respectfully disagrees and underscores that the question is what the prior art would have reasonably suggested to one skilled in the art (MPEP 2145 (IV)). Yushin discloses a cross-linked organic copolymer; Kay teaches benefits of using an inorganic binder as the cross-linker; and Huang teaches the benefits of each of PAA and PVA. As the skilled artisan would understand that each binder must be present to perform its function without sacrificing the other binders’ effects, Kay and Huang implicitly recognize each binder’s content as result-effective and, thus, optimizable under MPEP 2144.05 (II).
Regarding claim 21, as established above, this claim is withdrawn, rendering arguments against it moot.
Regarding claim 26, specifically that Huang’s 60:40 is outside the claimed range, Examiner respectfully reiterates the above response and notes that Huang does not teach away from other ranges by teaching the preferred embodiment (note comparable tensility at similar ratios in fig. 2 and see MPEP 2123 (I) and (II)). Indeed, the skilled artisan would recognize that any modification necessarily includes advantages and trade-offs (see also MPEP 2143.01 (V.)), yet, more broadly, it still appears that the skilled artisan must necessarily account for each binder’s content and, thus, would have reached the instant ratio by optimizing the A:B:C ratio to balance above considerations such as strength, flexibility, capacity, and cyclability.
Conclusion
The prior art made of record but not relied upon is considered pertinent to Applicant’s disclosure:
CN 114341304 A (citation to English equivalent US 20230141592 A1): binder composition containing copolymer of carboxylic-acid monomer and amide-containing monomer, which may be cross-linked with, e.g., a phosphate salt.
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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/J.S.M./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 1/12/2026
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