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
The amendment filed on 2 March 2026 has been entered. Claims 1 and 13 are currently amended and claims 2-5 are canceled. Claims 1 and 6-13 are currently pending and examined herein.
The rejections of claims 2-5 are obviated by cancellation of the claims.
The rejection of claims 1 and 8-13 under 35 USC 103 as unpatentable over Hayashi et al in view of Togashi et al is withdrawn due to applicant’s amendment.
The rejection of claims 6 and 7 as unpatentable over Hayashi et al in view of Togashi et al and Umehara is withdrawn due to applicant’s amendment.
New rejections follow.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries 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.
Claims 1 and 8-13 are rejected under 35 U.S.C. 103 as being unpatentable over Hayashi et al (JP2020181636A) in view of Togashi et al (JP2020161426A), Liu et al (CN111139002A) and Kang et al. (US 2012/0183848 A1).
Regarding claims 1 and 13, Hayashi teaches an electronic apparatus such as an electric vehicle or a portable power source for personal computers ([0002]), wherein the electronic apparatus comprises an electrochemical apparatus such as a secondary battery (machine translation [0013]) comprising: a positive electrode 50, wherein the positive electrode comprises a current collector 52; the current collector comprises a coated region provided with an active material 54, and an uncoated region (Fig. 2, reproduced below shows a region to the left that is uncoated with the active material); the uncoated region is at least partially provided with an insulation layer 56 (Fig. 2 shows the region uncoated with active material 54 at least partially covered with insulation layer 56, [0019]), the insulation layer comprises a binder and inorganic particles ([0020] teaches the insulation layer 56 contains an inorganic filler (inorganic particles), a binder, and a thickener).
Additionally, Hayashi teaches in paragraphs [0007] and [0021] the mass ratio (A:B+C) of the inorganic filler (A) to the binder (B) and the thickener (C) is characterized by being 98:2 to 60:40; i.e., 60%-98% of the insulation layer is inorganic filler. Paragraph [0020] teaches the filler can be alumina Al2O3; given the molar mass of Al2O3 as 101.96 g/mol and the mass% of Al in alumina as 53.96/101.96 or about 53%, the mass percentage of element aluminum in the corresponding insulation layer would be 32% to 52%, which overlaps with the claimed range. Alternatively, paragraph [0020] also teaches the filler can be boehmite, which has a molecular weight of approximately 59.99 g/mol and the mass% of Al in boehmite is about 45%, therefore the mass percentage of element aluminum in the corresponding insulation layer would be 27% to 44%, which also overlaps with the claimed range).
Fig. 2 of Hayashi:
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Hayashi further teaches the binder preferably contains an acrylic resin, wherein examples of the acrylic resin include monomers, copolymers, oligomers, and polymers of acrylic acid, methacrylic acid, and the like ([0020]).
Hayashi does not teach that an adhesion between the insulation layer and the current collector is not less than 300 N/m.
In a similar field of endeavor, Togashi teaches an electrode which can be a positive or negative electrode with an insulation layer 44 formed on the electrode substrate 42 (Fig. 2, reproduced below, machine translation [0031], [0072]) wherein the lower limit of the peel strength between the insulation layer and the electrode base material can be set to 0.2 N/mm or more ([0058]). Togashi further teaches by setting the peel strength between the insulation layer and the electrode base material as described above, it is possible to prevent the insulation layer from peeling off. Primary Hayashi teaches the importance of having an insulation layer that has improved adhesion to the exposed portion of the current collector and improved physical strength in preventing short circuits ([0005]). One of ordinary skill in the art would have been motivated to modify Hayashi’s electrochemical apparatus such that its peel strength is at least 0.2 N/mm or more (i.e., 200 N/m) as taught by Togashi, to prevent the insulation layer from peeling off, thereby overlapping with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05.
Figure 2 of Togashi:
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Modified Hayashi does not teach that the binder specifically comprises a polymer formed by polymerization of monomers of acrylonitrile (25-70 mass%), acrylate (10-60 mass%), acrylamide (10-60 mass%), or acrylic ester at a mass percentage that is more than 0% and less than or equal to 10%.
In the same field of endeavor, Liu teaches a water-soluble adhesive for lithium-ion batteries comprising a monomer of formula 1, a monomer of formula 2, and a monomer of formula 3, forming a multi-component copolymer ([0007]), and wherein the monomers of the formulas can be the following species ([0019] with the following mass percentages within the water-soluble adhesive in parentheses ([0007]): the monomer of Formula 1 of the present invention can be acrylic acid, methacrylonitrile, or acrylonitrile (5-75% monomer); the monomer of Formula 2 is N,N-diethylacrylamide, acrylamide, or 2-acrylamide-2-phenylethanesulfonic acid (1-35% monomer); and the monomer of Formula 3 is acrylonitrile, sodium acrylate, acrylic acid, or methacrylic acid (5-65% monomer).
Primary reference Hayashi teaches a goal to provide a secondary battery equipped with an insulating layer that has improved adhesion to the exposed portion of the current collector and improved physical strength ([0005]). One of ordinary skill in the art would have thus been motivated to modify modified Hayashi’s electrochemical apparatus to utilize Liu’s water-soluble adhesive as the binder within the insulating layer to improve bonding strength as taught by Liu, which would be expected to improve adhesion to the exposed portion of the current collector, a feature taught as important by Hayashi.
Although the teachings of Liu lack the presence of an acrylic ester in this class of binders (i.e. binders including an acrylic resin, as contemplated by Hayashi et al. [0020]), Kang et al is cited as showing inclusion of acrylic ester at a level of e.g. 10% within a binder for secondary batteries having excellent adhesive force, among other binder components of the types used by Liu. [0016]-[0017] It is considered that in the absence of a showing of anything unexpected by its inclusion, selection of such conventional binder polymer monomers at levels known to be suitable for the application would be within the level of skill of one having ordinary skill in that art at the time the invention was made. The addition of acrylic ester would have predictably resulted in a suitable binder. See MPEP 2143(I)(A).
Accordingly, the combination of prior art teaches the limitation wherein the polymer is formed by polymerization of monomers of acrylonitrile, acrylate, acrylamide and acrylic ester, wherein the taught ranges overlap wherein based on a total mass of the polymer, a mass percentage of the acrylonitrile is 25%-70%, a mass percentage of the acrylate is 10% to 60%, a mass percentage of the acrylamide is 10% to 60%, and a mass percentage of the acrylic ester is more than 0% and less than or equal to 10%.
Regarding claim 8, the combination above teaches the electrochemical apparatus of claim 1 and further teaches wherein based on the total mass of the insulation layer, a mass percentage of the binder is 2% to 50%, and a mass percentage of the inorganic particles is 50% to 98% (Hayashi teaches in [0021]: Regarding the mass ratio of the materials constituting the insulation layer 56, if the total (A+B+C) of the inorganic filler (A), binder (B), and thickener (C) is 100, it is preferable that the mass ratio of the binder (B) be, for example, approximately 1.5 to 35, i.e. 1.5% - 35%, which overlaps with the claimed range for the mass percentage of the binder. Hayashi further teaches in the same paragraph that the preferred mass ratio (A:B+C) of the inorganic filler to the binder and thickener is 98:2 to 60:40, i.e. 60% - 98%, which is within the claimed range for the mass percentage of the inorganic particles).
Regarding claim 9, the combination above teaches the electrochemical apparatus of claim 1 and Hayashi further teaches that preventing the insulation layer from falling off of the current collector can more reliably prevent short circuit ([0003] para 2) and that preventing damage such as cracks or breaks in the insulation layer can also more reliably prevent short circuit ([0005]). Therefore, one of ordinary skill in the art at the time of filing would have found it obvious and have been motivated to form the insulation layer of modified Hayashi with sufficient adhesion to avoid the layer from falling off of the current collector and to avoid cracks and breaks in the insulation layer to thereby avoid the risk of short circuit. If the insulation layer neither falls off the current collector nor has cracks or breaks, then it has continuous film coverage over its region on the current collector and would overlap with a cover rate of not less than 90%.
Regarding claim 10, the combination above teaches the electrochemical apparatus of claim 1. Togashi of the combination teaches the average thickness of the insulating layer can be between 3 µm to 30 µm ([0068]). Togashi also teaches by setting the average thickness of the insulating layer to the above upper limit or less, it is possible to make the energy storage element thinner and improve the energy density ([0068]). It would have been obvious to one of ordinary skill in the art at the time of filing to have modified the electrochemical apparatus of modified Hayashi to use an insulation layer with a thickness between 3 µm to 30 µm for the benefit of making the energy storage element thinner and improve the energy density, as taught by Togashi, and thereby overlapping with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05.).
Additionally, as demonstrated by Togashi’s teaching above, thickness of the insulation layer is a result-effective variable. One of ordinary skill in the art would have also been motivated to utilize routine experimentation to adjust the thickness of the insulation layer of modified Hayashi to optimize the energy density, as taught by Togashi, and arrived at the claimed range of thickness as a result.
Regarding claim 11, the combination above teaches the electrochemical apparatus of claim 1.
Togashi of the combination teaches particle size of the inorganic filler affects the electrolyte permeability and the non-conductivity of the insulating layer, specifically disclosing “By setting the particle size of the filler within the above range, it is possible to further increase the electrolyte permeability while maintaining sufficient nonconductivity” ([0061]). Particle size distribution is correspondingly expected to be a result-effective variable. Togashi further teaches a range for average particle size such as between 0.5 µm and 10 µm ([0061]). One of ordinary skill in the art at the time of filing would have been motivated to apply routine experimentation to adjust the particle size distribution of the inorganic particles of the modified electrochemical apparatus of Hayashi to optimize the electrolyte permeability and nonconductivity of the insulating layer as taught by Togashi and would have arrived at the claimed range.
Regarding claim 12, the combination above teaches the electrochemical apparatus of claim 1 and Hayashi further teaches the inorganic particles can be boehmite or alumina ([0020]), which includes the claimed species.
Claims 6-7 are rejected under 35 U.S.C. 103 as being unpatentable over Hayashi et al (JP2020181636A) in view of Togashi et al (JP 2020161426 A), Liu et al (CN111139002A) and Kang et al. (US 2012/0183848 A1) as applied to claim 1 above, and further in view of Umehara (JP2020047506A).
Regarding claim 6, the combination above teaches the electrochemical apparatus of claim 1, but does not teach wherein the binder has a weight-average molecular weight of 100,000 to 2,000,000.
In the same field of endeavor, Umehara teaches an insulating layer with binder molecular weight in the range of 500,000 to 1,500,000 (machine translation [0043], Fig. 6). Umehara teaches the taught range of binder molecular weight, in addition to weight ratios of the binder and solid contents within the electrode mixture paste and insulating material paste ([0032]), provides a variable for adjusting the viscosity of the insulating paste 230 forming the insulating layer such that it is approximately the same as that of the electrode mixture paste 220, which has been found to suppress coating defects and thickness variations, making it possible to form the active material layer and insulating layer with the desired uniform thickness ([0033]). One of ordinary skill in the art at the time of filing would have found it obvious to have modified the modified electrochemical apparatus of Hayashi to use Umehara’s binder of molecular weight in the range of 500,000 to 1,500,000 and adjust the solids content and binder weight ratios within the electrode mixture paste and the insulating material paste to match their viscosities and form active material layer and insulating layers free of coating defects and thickness variations. Accordingly, within the combination, the molecular weight range of 500,000 to 1,500,000 taught by Umehara is within the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05.
Regarding claim 7, the combination above teaches the electrochemical apparatus of claim 1, but does not teach wherein the binder has a weight-average molecular weight of 300,000 to 800,000.
In the same field of endeavor, Umehara teaches an insulating layer with binder molecular weight in the range of 500,000 to 1,500,000 (machine translation [0043], Fig. 6). Umehara teaches the taught range of binder molecular weight, in addition to weight ratios of the binder and solid contents within the electrode mixture paste and insulating material paste ([0032]), provides a variable for adjusting the viscosity of the insulating paste 230 forming the insulating layer such that it is approximately the same as that of the electrode mixture paste 220, which has been found to suppress coating defects and thickness variations, making it possible to form the active material layer and insulating layer with the desired uniform thickness ([0033]). One of ordinary skill in the art at the time of filing would have found it obvious to have modified the modified electrochemical apparatus of Hayashi to use Umehara’s binder of molecular weight in the range of 500,000 to 1,500,000 and adjust the solids content and binder weight ratios within the electrode mixture paste and the insulating material paste to match their viscosities and form active material layer and insulating layers free of coating defects and thickness variations. Accordingly, within the combination, the molecular weight range of 500,000 to 1,500,000 taught by Umehara overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05.
Response to Arguments
Applicant's arguments filed 2 March 2026 have been fully considered but they are not persuasive.
Applicant alleges criticality of the limitation that the adhesion between the insulation layer and the current collector is not less than 300 N/m, pointing out that in the examples of the specification, 300 N/m is the point at which the pass rate of the side nail penetration test becomes 100%.
While this observation is true, the evidence offered falls short of demonstrating criticality, at least because the evidence offered is not commensurate in scope with the claimed invention.
As an initial matter, among the 28 examples and 7 comparative examples presented in Table 1, there is only one example in which acrylic ester is present (Example 12), and this example is shown to have an adhesion strength of 230 N/m and an 80% pass rate of the side nail penetration test. There is no example shown in Table 1 that actually corresponds to all limitations of instant claim 1.
In addition, the adhesion strength is not demonstrated to be a critical parameter in determining the pass rate for the full breadth of the claim. For example, all examples of table 1 are disclosed as having the same insulation layer thickness (6 µm), while the claim is not so limited. While adhesion corresponding to claim 1 is reported for other thicknesses in Table 2, no nail penetration test results are reported. Whether a battery fails nail penetration tests is known within the art to depend on numerous factors that are not recited within the claims (e.g. battery geometry, state of charge, etc.). The data presented fail to demonstrate that adhesion of 300 N/m is the critical threshold for a 100% nail penetration test pass rate for an electrochemical apparatus according to the claims.
Applicant’s further arguments regarding the lack of an acrylic ester in the binder provided by the prior art is moot in view of the new ground of rejection relying on the further teaching of Kang et al.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/JEFFREY T BARTON/Supervisory Patent Examiner, Art Unit 1726 25 June 2026
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