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 .
The Applicant’s amendment filed on 3/27/2026 was received. Claims 1, 16 were amended. Claims 17, 18 were newly added.
The text of those sections of Title 35, U.S.C. code not included in this action can be found in the prior Office action issued on 12/29/2025.
Claim Rejections - 35 USC § 102/103
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-4, 7-10, 12, 13, 15-18 remain rejected under 35 U.S.C. 102 (a) (1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as being obvious over Hatanaka (CN 1728439 A). The rejections are restated below to address the amendment.
Regarding to claims 1, 16: Hatanaka discloses lithium-ion secondary batteries (par. 2). The lithium-ion secondary batteries (equivalent to an electrochemical apparatus) comprise: a positive electrode (11) (par. 46, fig. 2) (equivalent to an electrode), wherein the positive electrode (11) comprises a positive current collector (11a) (par. 46, fig. 2) and a positive electrode flux layer (11b) (par. 46, fig. 2). The positive electrode flux layer (11b), containing an active material (par. 70), is on the positive current collector (11a) (equivalent to a coated region). A porous heat-resistant layer (14) (par. 47, fig. 2) (equivalent to an insulation layer) is provided along the boundary between the positive electrode flux layer and the exposed portion of the positive electrode current collector (par. 47, fig. 2) (equivalent to an uncoated region provided with no active material). (fig. 2). The porous heat-resistant layer (14) comprises a binder and insulating fillers (equivalent to inorganic particles) (par. 61). The binder contains acrylonitrile (par. 65). The insulating fillers can be bauxite, magnesium oxide, titanium dioxide, and/or silica (par. 64). The amount of binder contained in the porous heat-resistant layer is preferably 1 to 5 parts by weight relative to 100 parts by weight of insulating filler (par. 69) (equivalent to a mass percentage of the binder is 0.99% to 4.7%, and a mass percentage of the inorganic particles is approximately 95% to 99% based on a total mass of the insulation layer). Hatanaka further discloses the lithium-ion secondary battery comprise an electrolyte which is a solution containing EC, DEC, and DMC (dimethyl carbonate) in Example 1 (par. 119).
Hatanaka does not specifically disclose a swelling rate of the insulation layer is not higher than 8% after the insulation layer is immersed in dimethyl carbonate as an electrolyte at 85°C for 24h. However, it is the position of the examiner that such properties are inherent, given that both Hatanaka and the present application utilize the same binder (acrylonitrile) and have similar mass percentage of the binder in the porous heat-resistant layer (14). A reference which is silent about a claimed invention’s features is inherently anticipatory if the missing feature is necessarily present in that which is described in the reference. In re Robertson, 49 USPQ2d 1949 (1999).
Alternatively, Hatanaka recognizes the binders swell after absorbing the electrolyte. Therefore, the less binder added to the porous heat-resistant layer (14), the less the porous heat-resistant layer (14) swells (par. 65). Hatanaka further recognizes less binder leads to better ion conductivity but poor mechanical strength of the porous heat-resistant layer (par. 69). Therefore, one of ordinary skill in the art before the effective filing date of the claimed invention can adjust the weight percentage of the binder in the porous heat-resistant layer (14) to yield more or less swelling rate of the porous heat-resistant layer (14), thereby achieving an optimal balance between ion conductivity and poor mechanical strength. Discovery of optimum value of result effective variable in known process is ordinarily within skill of art. In re Boesch, CCPA 1980, 617 F.2d 272, 205 USPQ215.
Regarding to claim 2: Hatanaka discloses lithium-ion secondary batteries as described above. Hatanaka does not specifically disclose a swelling rate of the insulation layer is not higher than 5% after the insulation layer is immersed in as an electrolyte at 85°C for 24h. However, it is the position of the examiner that such properties are inherent, given that both Hatanaka and the present application utilize the same binder (acrylonitrile) and have similar mass percentage of the binder in the porous heat-resistant layer (14). A reference which is silent about a claimed invention’s features is inherently anticipatory if the missing feature is necessarily present in that which is described in the reference. In re Robertson, 49 USPQ2d 1949 (1999).
Alternatively, Hatanaka recognizes the binders swell after absorbing the electrolyte. Therefore, the less binder added to the porous heat-resistant layer (14), the less the porous heat-resistant layer (14) swells (par. 65). Hatanaka further recognizes less binder leads to better ion conductivity but poor mechanical strength of the porous heat-resistant layer (par. 69). Therefore, one of ordinary skill in the art before the effective filing date of the claimed invention can adjust the weight percentage of the binder in the porous heat-resistant layer (14) to yield more or less swelling rate of the porous heat-resistant layer (14), thereby achieving an optimal balance between ion conductivity and poor mechanical strength. Discovery of optimum value of result effective variable in known process is ordinarily within skill of art. In re Boesch, CCPA 1980, 617 F.2d 272, 205 USPQ215.
Regarding to claim 3: Hatanaka discloses the binder contains acrylonitrile (par. 65).
Regarding to claim 4: Hatanaka discloses the binder contains acrylonitrile (par. 65). It is noted that limitation of “formed by polymerization of monomers” in claim 4 is a product-by-process limitation. “Even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F. 2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
Regarding to claims 7, 8: Hatanaka discloses the binder contains acrylonitrile (par. 65). The weight average molecular weight of an acrylonitrile polymer can be 50,000 to 1,000,000 as evidenced by Tatsuno et al. (US 20190148739 A1) (par. 118 in Tatsuno). 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(I).
Regarding to claim 9: Hatanaka discloses the amount of binder contained in the porous heat-resistant layer is preferably 1 to 5 parts by weight relative to 100 parts by weight of insulating filler (par. 69) (equivalent to a mass percentage of the binder is 0.99% to 4.7%, and a mass percentage of the inorganic particles is approximately 95% to 99% based on a total mass of the insulation layer).
Regarding to claim 10: Hatanaka discloses the porous heat-resistant layer should be applied to where the cutting burrs are generated in the electrode to prevent short circuit (par. 48, 49, 50, 58). 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 porous heat-resistant layer insulation layer of Hatanaka with sufficient coverage on the uncoated region of the collector to 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 95%.
Regarding to claim 12: Hatanaka discloses the insulating fillers have an average particle diameter of 0.5 μm (par. 116, 124).
Regarding to claim 13: Hatanaka discloses the thickness of the porous heat-resistant layer is set to 0.8μm, 1μm, 10μm or 12μm (par. 122).
Regarding to claim 15: Hatanaka discloses lithium-ion secondary batteries (par. 2) as described above. Hatanaka fails to explicitly disclose compared with another electrochemical apparatus of the same specifications without the insulation layer and stored at 85°C for 24h or 60°C for 30 days, the electrochemical apparatus stored at 85°C for 24h or 60°C for 30 days satisfies at least one of the following characteristics: (a) a difference between thickness growth rates of the electrochemical apparatus and the another electrochemical apparatus being within ±8%; or (b) a difference between internal resistance growth rates of the electrochemical apparatus and the another electrochemical apparatus being within ±8%. Hatanaka recognizes the binders swell after absorbing the electrolyte. Therefore, the less binder added to the porous heat-resistant layer (14), the less the porous heat-resistant layer (14) swells (par. 65) (the less the porous heat-resistant layer (14) swells, the lower the thickness growth rate of the batteries is). Hatanaka further recognizes less binder leads to better ion conductivity but poor mechanical strength of the porous heat-resistant layer (par. 69). Therefore, one of ordinary skill in the art before the effective filing date of the claimed invention can adjust the weight percentage of the binder in the porous heat-resistant layer (14) to yield more or less swelling rate of the porous heat-resistant layer (14) (which influences the thickness growth rate of the batteries), thereby achieving an optimal balance between ion conductivity and poor mechanical strength. Discovery of optimum value of result effective variable in known process is ordinarily within skill of art. In re Boesch, CCPA 1980, 617 F.2d 272, 205 USPQ215.
Regarding to claims 17, 18: Hatanaka discloses the binder contains acrylonitrile (par. 65). The weight average molecular weight of an acrylonitrile polymer can be 50,000 to 1,000,000 as evidenced by Tatsuno et al. (US 20190148739 A1) (par. 118 in Tatsuno). 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(I).
Claim Rejections - 35 USC § 103
Claims 5, 6 remain rejected under 35 U.S.C. 103 as being unpatentable over Hatanaka (CN 1728439 A) as applied in claim 4 above, and further in view of Liu et al. (CN 111139002 A), hereinafter Liu 002.
Regarding to claim 5: Hatanaka discloses the binder contains acrylonitrile (par. 65) as described in paragraph 2 above. Hatanaka fails to explicitly disclose the polymer is formed by polymerization of the monomers of the acrylonitrile, the acrylate, acrylamide, and the acrylic ester; and based on a total mass of the polymer, a mass percentage of the acrylonitrile is 25% to 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 0% to 10%. However, Liu 002 discloses a water-soluble binder for lithium-ion batteries (par. 6). The water-soluble binder comprises a monomer of formula 1, a monomer of formula 2, and a monomer of formula 3, forming a multi-component copolymer (par. 7, 35), and wherein the monomers of the formulas can be the following species (with the following mass percentages within the water- soluble adhesive in parentheses ): 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) (par. 7, 19, 20). The copolymer does not include acrylic ester, therefore the mass percentage is 0%. It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to use the water-soluble binder of Liu 002 in the porous heat-resistant layer (14) of Hatanaka because Liu 002 teaches that the water-soluble binder has low electrolyte swelling characteristics and can improve high-temperature cycling performance (par. 48, 128). 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(I).
In addition, it is noted that limitation of “formed by polymerization of monomers” in claim 5 is a product-by-process limitation. “Even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F. 2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
Regarding to claim 6: Hatanaka discloses the binder contains acrylonitrile (par. 65) as described in paragraph 2 above. Hatanaka fails to explicitly disclose a swelling rate of the binder in the electrolyte is 0% to 5%. However, Liu 002 discloses a water-soluble binder for lithium-ion batteries (par. 6). The water-soluble binder comprises a monomer of formula 1, a monomer of formula 2, and a monomer of formula 3, forming a multi-component copolymer (par. 7, 35). The water-soluble binder for lithium-ion batteries of the present invention has an electrolyte swelling degree of <10% after soaking at 70°C for 7 days (par. 128). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to use the water-soluble binder of Liu 002 in the porous heat-resistant layer (14) of Hatanaka because Liu 002 teaches that the water-soluble binder has low electrolyte swelling characteristics and can improve high-temperature cycling performance (par. 48, 128). 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(I).
In addition, Liu 002 recognizes that the lower electrolyte swelling characteristics result in better adhesion (par. 48). Liu 002 further recognizes the swelling degree can be controlled by the mass percentage of the three types of monomers (par. 102). Therefore, one of ordinary skill in the art before the effective filing date of the claimed invention can adjust the mass percentage of the three types of monomers to yield a desired swelling rate of the binder and a desired adhesion. Discovery of optimum value of result effective variable in known process is ordinarily within skill of art. In re Boesch, CCPA 1980, 617 F.2d 272, 205 USPQ215.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Hatanaka (CN 1728439 A) as applied in claim 1 above, and further in view of Liu et al. (US 20220123444 A1), hereinafter Liu 444 et al.
Regarding to claim 11: Hatanaka discloses the insulating fillers (equivalent to inorganic particles) can be bauxite, magnesium oxide, titanium dioxide (par. 64). Hatanaka fails to explicitly disclose the inorganic particles comprise at least one of boehmite, diaspore, aluminum oxide, barium sulfate, calcium sulfate, or calcium silicate. However, Liu 444 et al. disclose an electrode assembly including an insulation layer (abstract). The insulation layer (113) is coated on a surface without active material layer (112) (par. 98, fig. 7, 8). The insulation layer (113) comprises an inorganic filler and a binder (par. 12). The binder can be polyacrylonitrile (par. 99). The inorganic fillers can be one or more of boehmite, aluminum oxide, magnesium oxide, titanium dioxide, zirconium oxide, silicon dioxide, silicon carbide, boron carbide, calcium carbonate, aluminum silicate, calcium silicate, potassium titanate, or barium sulfate (par. 99). Since the Liu 444 et al. recognizes the magnesium oxide, titanium dioxide and boehmite, aluminum oxide, calcium silicate, barium sulfate are functionally equivalent inorganic fillers used in the insulation layer, it would have been obvious to one of ordinary skill in the art at the time of the invention to substitute the magnesium oxide, titanium dioxide of Hatanaka with the magnesium oxide, titanium dioxide and boehmite, aluminum oxide, calcium silicate, barium sulfate of Liu 444 et al. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
Claim 14 remains rejected under 35 U.S.C. 103 as being unpatentable over Hatanaka (CN 1728439 A) as applied in claim 1 above, and further in view of Togashi et al. (JP 2020161426 A).
Regarding to claim 14: Hatanaka discloses lithium-ion secondary batteries as describe in paragraph 2 above. Hatanaka fails to explicitly disclose an adhesion between the insulation layer and the current collector is not less than 201 N/m. However, Togashi et al. disclose a method for manufacturing an electrode and an electrode (par. 1). The electrode (41) includes a strip-shaped electrode substrate (42) (equivalent to a current collector) (par. 31, fig. 8). A mixture layer (43) (equivalent to an active material) is formed on the electrode substrate (42) (par. 31, fig. 8). An insulating layer (44) (equivalent to an insulation layer) is formed on the uncoated portion of the electrode substrate (42) (par. 31, fig. 8). The peel strength between the insulating layer and the electrode base material is 0.2 N/mm or more (equivalent to 200 N/m). In addition, Togashi et al. recognizes the high peeling strength can be achieved by induction heating method (par. 22). Therefore, one of ordinary skill in the art before the effective filing date of the claimed invention can modify the heating method to enhance the pealing strength between the insulation layer and the current collector. Discovery of optimum value of result effective variable in known process is ordinarily within skill of art. In re Boesch, CCPA 1980, 617 F.2d 272, 205 USPQ215.
Response to Amendment
Applicant’s arguments filed on 03/27/2026 have been fully considered but they are not persuasive. Applicant primarily argues:
None of the cited prior art references teach or suggest using dimethyl carbonate as the electrolyte for measuring the swelling rate of the insulation layer.
The prior art does not recognize dimethyl carbonate or the specific test conditions (85°C for 24h) as result-effective variables.
In response:
Applicant’s arguments are not persuasive. It is the position of the examiner that swelling rate of the insulation layer is an inherent property, given that Hatanaka discloses the same binder (acrylonitrile) and has similar mass percentage of the binder in the insulation layer to the instant application. Dimethyl carbonate is a common solvent in an electrolyte as evidence by Example 1 in Hatanaka. Thus, one of ordinary skill in the art could choose dimethyl carbonate as the electrolyte for swelling rate test.
Applicant’s arguments are not persuasive. The swelling rate is the result-effect variable to the ion conductivity and mechanical strength. The test conditions (dimethyl carbonate, 85°C for 24h) do not change the structural feature of the insultation layer.
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 PIN JAN WANG whose telephone number is (571)272-7057. The examiner can normally be reached M-F 9am-5pm.
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/PIN JAN WANG/Examiner, Art Unit 1717
/Dah-Wei D. Yuan/Supervisory Patent Examiner, Art Unit 1717
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