DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/02/2026 has been entered.
Response to Amendment
In response to the amendment received 02/02/2026, the 35 U.S.C. 103 rejection of claim 9 has been withdrawn from the previous office action.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1, 8, 10-12, and 14-15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Foreign Publication KR20130045601A (used attached machine translation), hereafter Kim, in view of Published Application US20060078791A1, hereafter Hennige, and further in view of Foreign Publication EP3429015A1, hereafter Min.
Regarding claim 1, Kim discloses a separator (100) for an electrochemical device ([0001]), comprising:
a porous polymer substrate ([0022] porous substrate 110; [0028] polyolefin-based) having a first surface and a second surface opposite to the first surface (Fig 1, first and second surfaces);
a first porous coating layer (120) on the first surface of the porous polymer substrate (110) ([0022], Fig 1),
wherein the first porous coating layer (120) comprises first inorganic particles, and a first binder polymer on all or part of a surface of the first inorganic particles to connect and hold the first inorganic particles together ([0022] mixture of inorganic particles and first binder polymer), wherein an interstitial volume is formed between the first inorganic particles in contact with each other and the interstitial volume is a void space which forms pores ([0023] interstitial volume between inorganic particle forms pores);
the first porous coating layer comprising:
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a plurality of nodes comprising second inorganic particles and a second binder polymer coating at least part of a surface of the second inorganic particles ([0022] mixture of inorganic particles and first binder polymer) (see annotated Fig 4); and
a plurality of filaments formed from the second binder polymer, each filament having a thread shape, each filament extending between a pair of nodes of the plurality of nodes, wherein the plurality of filaments define a 3-dimensional network structure in which the plurality of filaments cross each other (see annotated Fig 4); and
an electrode adhesion layer (130) on a surface of the first porous coating layer (120) opposite to the porous separator substrate (110) (Fig 1, [0024] electrode adhesive layer 130 on porous coating layer 120),
wherein the electrode adhesion layer (130) comprises a third binder polymer ([0024] electrode adhesive layer 130 includes second binder polymer),
wherein the first porous coating layer and the second porous coating layer have different pore structures (implicit, since the term “different” is a broad term, and each porous layer will necessarily have a slightly different pore structure due to natural variation imparted by the manufacturing process),
wherein the first binder polymer comprises carboxymethylcellulose ([0032] carboxymethylcellulose), or wherein the second binder polymer comprises poly(vinylidene fluoride-co-hexafluoropropylene) ([0032] poly(vinylidene fluoride-co-hexafluoropropylene)).
Kim is silent on a specific embodiment where the porous coating layer (120) is formed on both surfaces of the porous separator substrate (110), but Kim does suggest the addition a second porous coating layer on the second surface of the porous polymer substrate ([0022] porous coating layer 120 formed on at least one surface, suggesting it may be formed on the other surface as well),
In the analogous art of layered battery separators, Hennige discloses two porous layers, one on either side of the substrate, where one layer has a smaller pore size than the other layer ([0020-0024] porous layers on either side of support with different pore sizes). Hennige further discloses this structure combines the advantages of large pores, which produce low internal resistances, and small pores in contact with the electrodes, which help avoid short circuiting ([0155]).
It would however have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to modify the invention of Kim to also apply the porous coating layer to the other side of the porous separator substrate with a different pore size as disclosed by Hennige, since Kim suggests as much by the use of the phrase “at least one surface” as stated above, since the separator necessarily contacts both electrodes, the benefits supplied by the porous coating layer being between the porous separator substrate and one electrode will also necessarily be beneficial to the other side of the separator and the second electrode, and finally, in order to combine the advantages of large pores, which produce low internal resistances, and small pores in contact with the electrodes, which help avoid short circuiting, as suggested by Hennige.
Kim is further silent on the first binder polymer comprising at least one of styrene butadiene rubber, acrylic polymer, carboxymethylcellulose, or polyvinylalcohol, and wherein the second binder polymer comprises a poly(vinylidene fluoride)-based copolymer.
In the analogous art of layered battery separators, Min discloses a similar multilayer separator with different binders in each of the layers on either side of the substrate ([0048] each layer can use the same binder or a different resin). Further, Min also discloses the use of both polyvinylidene fluoride-co-hexafluoropropylene and carboxymethylcellulose as binders ([0049]).
It would however have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to modify the invention of Kim to select different binders such as polyvinylidene fluoride-co-hexafluoropropylene and carboxymethylcellulose as disclosed by both Kim and Min for each of the first binder polymer and the second binder polymer in the layers on either side of the separator substrate as disclosed by Min, as a selection of a known material based on its suitability for the intended purpose (MPEP 2144.07), that purpose being separator layer binders.
Regarding claim 8, Kim further discloses wherein the third binder polymer has a radius of gyration of 150 nm to 500 nm (the present specification discloses: page 23 lines 19-21, radius of gyration of the third binder polymer may differ depending on interaction between the binder polymer and the solvent, and may differ depending on the weight average molecular weight of the binder polymer; page 34 lines 18-19, third solvent for third binder polymer may be acetone; page 25 lines 1-4, third binder polymer comprises PVDF-co-HFP, and obtains the best effect. Since Kim discloses the third binder polymer to be PVDF-co-HFP ([0037]) and discloses the solvent to be acetone ([0012]), and since the weight average molecular weight of PVDF-co-HFP overlaps with the preferred range as shown in the rejection of claim 7, the examiner considers the radius of gyration to be inherently met by the disclosure of Kim).
Regarding claim 10, Kim further discloses wherein the second binder polymer comprises poly(vinylidene fluoride-co-hexafluoropropylene) ([0032] poly(vinylidene fluoride-co-hexafluoropropylene)).
Regarding claim 11, Kim further discloses wherein the third binder polymer comprises poly(vinylidene fluoride-co-hexafluoropropylene) ([0037] poly(vinylidene fluoride-co-hexafluoropropylene)).
Regarding claim 12, Kim further discloses wherein the separator for the electrochemical device has a thermal shrinkage of 20% or less in each of a machine direction and a transverse direction ([0023] thermal shrinkage is prevented (i.e. 0% thermal shrinkage)).
Regarding claim 14, Kim further discloses an electrochemical device ([0001] electrochemical device), comprising:
a positive electrode (necessarily present in the electrochemical device),
a negative electrode (necessarily present in the electrochemical device), and
a separator interposed between the positive electrode and the negative electrode (the separator is necessarily interposed between the positive and negative electrode, since that is its express purpose for existence),
wherein the separator is the separator for the electrochemical device according to claim 1 (see above rejection of claim 1).
Regarding claim 15, Kim further discloses wherein the electrochemical device is a lithium secondary battery ([0001]).
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Foreign Publication KR20130045601A (used attached machine translation), hereafter Kim, in view of Published Application US20060078791A1, hereafter Hennige, and further in view of Foreign Publication EP3429015A1, hereafter Min, as stated above for claim 1, and further as evidenced by Table 1: Handbook of Polymers Physical Properties and Synthesis. Retrieved from https://app.knovel.com/hotlink/itble/rcid:kpHPE00045/id:kt012QUL83/handbook-polymers-3rd/table-handbook-polymers.
Regarding claim 7, Kim discloses the invention as stated above for claim 1.
Kim further discloses the third binder polymer is polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) ([0037]).
According to Table 1 the mass average molecular weight for PVDF-HFP to be 98000-480000 g/mol, which overlaps with the claimed range of 250,000 to 500,000. 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)).
Claim(s) 2-6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Foreign Publication KR20130045601A (used attached machine translation), hereafter Kim, in view of Published Application US20060078791A1, hereafter Hennige, and further in view of Foreign Publication EP3429015A1, hereafter Min, as stated above for claim 1, and further in view of Foreign Publication KR20130123568A (supplied by applicant, used attached machine translation), hereafter Park.
Regarding claim 2, Kim is silent on wherein an average particles size of the first inorganic particles is smaller than an average particle size of the second inorganic particles.
In the analogous art of secondary battery separators, Park discloses wherein an average particles size of the first inorganic particles is smaller than an average particle size of the second inorganic particles ([0014] inorganic particles on first surface are different size from inorganic particles on second surface) in order to increase the battery output by the increase of porosity resulting from the larger particle size ([0012]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to modify the invention of Kim to use first inorganic particles that are of smaller size than the second inorganic particles, in order to increase battery output and reduce manufacturing cost, as suggested by Park ([0012]), and further because changes in size are not sufficient to patentably distinguish over the prior art (MPEP 2144.04 (IV) (A)).
Regarding claim 3, Park further discloses wherein the average particle size of the first inorganic particles is 0.01 to 0.99 times smaller than the average particle size of the second inorganic particles ([0016] first inorganic particles may be 10-200nm, second inorganic particles may be 0.5-2µm; therefore a first inorganic particle size of e.g. 200nm is 0.4 times smaller than a second inorganic particle size of 0.5µm).
Regarding claim 4, Park further discloses wherein the average particle size of the first inorganic particles is 10nm to 800nm ([0016] 10-200nm).
Regarding claim 5, Park further discloses wherein the average particle size of the second inorganic particles is 500nm to 2000nm ([0016] 0.5-2µm), which overlaps with the claimed range of 200nm to 1000 nm. 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, Kim is silent on wherein an average pore size of the first porous coating layer is 40 nm to 150 nm.
In the analogous art of secondary battery separators, Park discloses that increased porosity in the separator results in increased battery life and increased battery output.
As the battery life and battery output is/are variable(s) that can be modified, among others, by adjusting the porosity (pore size) of the separator, with the battery life and battery output increasing as the porosity of the separator is increased, the pore size of the first porous coating layer would have been considered a result effective variable by one having ordinary skill in the art before the effective filing date of the present invention. As such, without showing unexpected results, the claimed average pore size of the first porous coating layer cannot be considered critical. Accordingly, one of ordinary skill in the art, before the effective filing date of the present invention, would have optimized, by routine experimentation, the average pore size of the first porous coating layer in the invention of Kim to obtain the desired battery life and battery output (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223).
Claim(s) 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Foreign Publication KR20130045601A (used attached machine translation), hereafter Kim, in view of Published Application US20060078791A1, hereafter Hennige, and further in view of Foreign Publication EP3429015A1, hereafter Min, as stated above for claim 1, and further in view of Published Application US20150303003A1, hereafter Ha.
Regarding claim 13, Kim is silent on wherein the separator for the electrochemical device has an adhesion strength with an electrode ranging from 70 gf/25 mm or more.
In the analogous art of secondary battery separators, Ha discloses wherein the separator for the electrochemical device has an adhesion strength with an electrode ranging from 70 gf/25 mm or more (Table 2, examples 1-6, 120, 85, 95, 105, 101, 108 gf/25 mm adhesiveness between layers of adhesion and electrodes).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to modify the invention of Kim to have an adhesion strength with an electrode ranging from 70 gf/25 mm or more, as disclosed by Ha, in order to provide the desired amount of bond between the separator and the electrode.
Response to Arguments
Applicant's arguments filed 02/02/2026 have been fully considered but they are not persuasive.
In response to applicant’s argument regarding claim 1 on page 6 of applicant’s remarks that claim 1 requires the first porous coating layer and the second porous coating layer have different pore structures, the rejection relies on Hennige for the disclosure as stated above.
In response to applicant’s argument regarding claim 1 on page 7 of applicant’s remarks that the different binders and manufacturing methods of the claimed first and second porous coating layers result in different pore structures, the examiner notes that the patentability of a product does not depend on its method of production (MPEP 2113 (I)).
In response to applicant’s argument regarding claim 1 on page 7 of applicant’s remarks in reference to the examiner’s previously proposed modification, this argument is rendered moot in view of the new 35 U.S.C. 103 rejection of claim 1 over Kim, Hennige and Min.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TIMOTHY HEMINGWAY whose telephone number is (571)272-0235. The examiner can normally be reached M-Th 6-4.
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/T.G.H./Examiner, Art Unit 1754
/SUSAN D LEONG/Supervisory Patent Examiner, Art Unit 1754
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