Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Election/Restrictions
Claims 13, 19 and 20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 6 November 2025.
Status of Claims
Claims 1-12, 15-18, and 21 as filed 6 November 2025 are examined herein. No new matter is included.
Claim Objections
Claims 8 and 9 are objected to because of the following informalities: an article (“a” or “the”) is required before “silane crosslinking reaction”. Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claims 1-12, 15-18, and 21 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Claim 1 includes the limitation “a separator… that is capable of forming a crosslinked structure … wherein the heat shrinkage factor at 150°C after formation of the crosslinked structure is 0.02 to 0.91 times the heat shrinkage factor at 150°C before formation of the crosslinked structure.” It is unclear if there is antecedent basis for "the crosslinked structure" since a modified polyolefin that is "capable of forming a crosslinked structure" appears to be an intended use limitation, and does not necessarily require the presence of a crosslinked structure. Regarding the broadest reasonable interpretation, as long as the modified polyolefin is capable of forming a crosslinked structure with the claimed heat shrinkage factor, the “the heat shrinkage factor at 150°C after formation of the crosslinked structure is 0.02 to 0.91 times the heat shrinkage factor at 150°C before formation of the crosslinked structure” will be interpreted as being met. Referring to the instant specification at [0083] a microporous membrane where the content of the polyolefin 50 wt% to 100 wt%, and the polyolefin having a weight-average molecular weight of 100,000 or higher and less than 1,000,000 would have the right heat shrinkage factor.
The limitations "capable of forming a crosslinked structure" and "heat shrinkage factor..." can also be considered intended use limitations such that under the broadest reasonable interpretation, this limitation will be met a microporous membrane where the content of the polyolefin is 50 wt% to 100 wt% and the polyolefin having a weight-average molecular weight of 100,000 or higher and less than 1,000,000. (See instant specification at [0083])
It is also not clear if the shrinkage factor of claim 1 applies to both layers or just to the first porous layer.
Claims 2, 12, and 15-18 stand rejected due to dependency.
Claim 8 includes the limitation “wherein silane crosslinking reaction of the silane-modified polyolefin is initiated when the separator for an electricity storage device contacts with an electrolyte solution.” This limitation is indefinite because the instant claim is a product claim not a process claim, and therefore is not clear what chemistry, structure or properties are associated with a separator meeting this limitation. Referring to the instant specification at [0033] a microporous separator comprising silane-modified polyolefin will meet the instant claim limitation.
Claim 9 includes a limitation related to storage modulus before and after crosslinking. This limitation is indefinite because the instant claim is a product claim not a process claim, and therefore is not clear what chemistry, structure or properties are associated with a separator meeting this limitation. Referring to the instant specification at [0024] a microporous separator where the polymer fraction of the separator comprises 5 to 40 weight% of a silane-modified polyolefin and 60 to 95 weight% of a polyolefin other than the silane-modified polyolefin will meet the instant claim limitation. It is noted that, as claimed, as long as the prior art discloses a separator comprising 5 to 40 weight% of a silane-modified polyolefin and 60 to 95 weight% of a polyolefin other than the silane-modified polyolefin, it will have been considered to have the requirements of the claim
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter 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 pre-AIA 35 U.S.C. 103(a) are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims under pre-AIA 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of pre-AIA 35 U.S.C. 103(c) and potential pre-AIA 35 U.S.C. 102(e), (f) or (g) prior art under pre-AIA 35 U.S.C. 103(a).
Claims 1-2, 12, and 15-18 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Ryu (KR 20160146134A, as cited by Applicant in an IDS, with references to the paragraph numbering of the English translation provided herewith).
Regarding claim 1, Ryu teaches a separator for an electricity storage device ([0001-0002]) comprising
a first porous layer (layer A) that includes a silane-modified polyolefin and is capable of forming a crosslinked structure, ([0003] separator … high porosity; [0011] polyolefin impregnated with silane) and
Regarding the limitation a second porous layer (layer B) that includes inorganic particles, Ryu discloses ([0005] (emphasis added) “to improve these low thermal properties, … improve the heat shrinkage phenomenon at high temperatures by coating the surface of polyethylene with inorganic substances”). A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to coat Ryu’s separator with an inorganic substance (e.g. inorganic particles) with a reasonable expectation of successfully creating a separator with improved thermal properties and reduced heat shrinkage at high temperatures.
Regarding the limitation wherein the heat shrinkage factor at 150°C after formation of the crosslinked structure is 0.02 to 0.91 times the heat shrinkage factor at 150°C before formation of the crosslinked structure, the broadest reasonable interpretation as set forth above includes “a microporous membrane where the content of the polyolefin 50 wt% to 100 wt%, and the polyolefin having a weight-average molecular weight of 100,000 or higher and less than 1,000,000 would have the right heat shrinkage factor.” (Refer to the instant specification at [0083].) Ryu at [0073] teaches the use of a silane master batch powder (3.34 wt%), HDPE (35 wt%), and liquid paraffin oil (65 wt%), where the liquid paraffin in subsequently extracted. Ryu at [0073] teaches that the HDPE has a weight-average molecular weight of 300,000. Examiner notes that HDPE is an example of a polyolefin. Therefore, Ryu’s separator meets the instant heat shrinkage factor limitations.
Regarding claim 2, Ryu teaches all of the limitations as set forth above, and Ryu further teaches wherein the crosslinked structure in layer A is formed by an acid, a base, swelling, or a compound generated inside the electricity storage device. ([0060] “crosslinking catalyst … organic bases, inorganic acids, and organic acids”)
Regarding claim 12, Ryu teaches all of the limitations as set forth above. Ryu further teaches an electricity storage device comprising an electrode, the separator for an electricity storage device according to claim 1, and a nonaqueous electrolyte solution. ([0003], [0068] “salts containing ions … dissolved or dissociated in organic solvents including … propylene carbonate”)
Regarding claim 15, Ryu teaches all of the limitations as set forth above. Ryu does not explicitly teach an electricity storage device assembly kit, comprising the following two elements:(1) an exterior body housing a laminated stack or wound body of electrodes and the separator for an electricity storage device according to claim 1; and (2) a container housing a nonaqueous electrolyte solution. However, Ryu teaches [0003] a battery comprising all of these components. A person of ordinary skill would understand that a product that is typically sold fully assembled (e.g. a battery) can be sold in an unfinished state (e.g. a battery with casing where the electrolyte in not yet installed.)
Regarding claim 16, Ryu teaches all of the limitations as set forth above. Ryu further teaches wherein the nonaqueous electrolyte solution includes a fluorine (F)-containing lithium salt. ([0069] PF6-)
Regarding claim 17, Ryu teaches all of the limitations as set forth above. Ryu further teaches wherein the nonaqueous electrolyte solution includes lithium hexafluorophosphate (LiPF6).
Regarding claim 18, Ryu teaches all of the limitations as set forth above. Ryu further teaches wherein the nonaqueous electrolyte solution is an acid solution and/or a base solution. ([0069] PF6-)
Claims 3-7, 9, 12 and 21 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Ryu (KR 20160146134A, as cited by Applicant in an IDS, with references to the paragraph numbering of the English translation provided herewith) in view of Murata (JP 2011000832A).
Regarding claim 3, Ryu teaches separator for an electricity storage device ([0001-0002]), which comprises:
a microporous membrane that includes a silane-modified polyolefin; ([0003] separator … high porosity; [0011] polyolefin impregnated with silane) and
Regarding the limitation an inorganic porous layer that includes inorganic particles and a resin binder, disposed on at least one surface of the microporous membrane. ([0005] (emphasis added) “to improve these low thermal properties, … improve the heat shrinkage phenomenon at high temperatures by coating the surface of polyethylene with inorganic substances”). A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to coat Ryu’s separator with an inorganic substance (e.g. inorganic particles) with a reasonable expectation of successfully creating a separator with improved thermal properties and reduced heat shrinkage at high temperatures. However, Ryu does not explicitly teach that the inorganic porous layer that includes a resin binder.
Murata, in the field (abstract) of battery separators, teaches [0006-0007] a multilayer porous film containing inorganic particles and a resin binder on at least one surface, for the purpose of suppressing thermal shrinkage. A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to Ryu’s inorganic substance coated separator with the resin binder of Murata, with a reasonable expectation of successfully suppressing thermal shrinkage.
Regarding claim 4, Ryu in view of Murata teaches all of the limitations as set forth above. Ryu does not explicitly teach wherein the content of the inorganic particles in the inorganic porous layer is 5 wt% to 99 wt%. Murata discloses [0032] that the mass percent of inorganic particles is preferably 50% to 99%, … from the viewpoint of permeability and heat resistance. (falls within the claimed range)
A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, modify Ryu’s separator with a mass percent of organic particles as taught by Murata, with a reasonable expectation of successfully balancing permeability and heat resistance.
Regarding claim 5, Ryu in view of Murata teaches all of the limitations as set forth above, and Ryu further teaches wherein the content of the silane-modified polyolefin in the microporous membrane is 0.5 wt% to 40 wt%. ([0073] silane master batch powder (3.34 wt%). HDPE (35 wt%))
Regarding claims 6 and 21, Ryu in view of Murata teaches all of the limitations as set forth above. However Ryu does not teach wherein the inorganic particles are one or more selected from the group consisting of alumina (Al2O3), silica, titania, zirconia, magnesia, ceria, yttria, zinc oxide, iron oxide, silicon nitride, titanium nitride, boron nitride, silicon carbide, aluminum hydroxide oxide (AIO(OH)), talc, kaolinite, dickite, nacrite, halloysite, pyrophyllite, montmorillonite, sericite, mica, amesite, bentonite, asbestos, zeolite, diatomaceous earth, quartz sand and glass fibers.
Murata discloses [0029] the use of aluminum oxide (also known as alumina) from the viewpoint of electrochemical stability and heat resistance. A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to select Murata’s alumina for the inorganic material coating of Ryu’s separator, with a reasonable expectation of successfully balancing permeability and heat resistance.
This also renders obvious the limitation of claim 21, wherein the inorganic particles are oxide-based ceramics.
Regarding claim 7, Ryu in view of Murata teaches all of the limitations as set forth above. However, Ryu does not teach wherein the glass transition temperature (Tg) of the resin binder is -50°C to 100°C. Ryu in view of Murata has rendered obvious the composition of the claimed separator. Because Ryu’s separator has the same composition as the claimed separator, it therefore is expected to have the claimed glass transition temperature, thus rendering obvious the claimed limitations.
Regarding claims 9 -11, Ryu in view of Murata teaches all of the limitations as set forth above. However Ryu does not teach wherein the separator meets specific storage modulus ratios and transition temperature. Referring to the instant specification at [0024], a microporous separator where the polymer fraction of the separator comprises 5 to 40 weight% of a silane-modified polyolefin and 60 to 95 weight% of a polyolefin other than the silane-modified polyolefin will meet the instant claim limitation.
Ryu at [0073] teaches the use of a silane master batch powder (3.34 wt%), HDPE (35 wt%), and liquid paraffin oil (65 wt%), where the liquid paraffin in subsequently extracted. The removal of the liquid paraffin creates a mixture having 8.7 weight % silane masterbatch, 93% HDPE. Because Ryu’s separator falls withing the ranges taught by the instant specification to meet the modulus limitations, it therefore is expected to meet the modulus limitations and transition temperature, thus rendering obvious the claimed limitations.
Claims 8 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Ryu (KR 20160146134A, as cited by Applicant in an IDS, with references to the paragraph numbering of the English translation provided herewith) in view of Murata (JP 2011000832A), as set forth in claim 3, above, and in further view of Satsuma (JP 2006179279A, using the translation provided by Applicant).
Regarding claim 8, Ryu in view of Murata teaches all of the limitations as set forth above. Regarding the limitation wherein silane crosslinking reaction of the silane-modified polyolefin is initiated when the separator for an electricity storage device contacts with an electrolyte solution, Ryu discloses [0006] that crosslinking may be initiated by peroxide initiators, water crosslinking using silane, and electron beam crosslinking. However, Ryu does not explicitly disclose initiation of the reaction by contact with an electrolyte solution.
Satsuma, in the field of electrolyte separators, discloses [0045] that an electrolyte solution containing a crosslinking agent may be injected into the battery container, further crosslinking the reactive polymer and causing the electrode sheet to be permanently bonded to the separator.
A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to use Satsuma’s in situ crosslinking with the separator of Ryu in view of Murata, with a reasonable expectation of successfully achieving the desirable result of causing the electrode sheet to be permanently bonded to the separator.
Conclusion
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CLAIRE A. RUTISER
Examiner
Art Unit 1751
/C.A.R./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 12/16/2025