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 .
Claim Rejections - 35 USC § 102
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)(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 1-5, 8-13, and 15 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by U.S. Patent Application Publication No. 2024/0347784 to Zhang ("Zhang" having an earliest effective filing date of August 20, 2021). Regarding claims 1-5, Zhang discloses a separator for use in a lithium ion battery. The separator includes a microporous membrane substrate upon which is coated one or more heat absorption layers. Zhang at Abstract and paragraph [0024]. In some embodiments the separator
further includes a ceramic coating on the microporous membrane. Id. at paragraphs [0024] and [0039].
In some embodiments the heat absorption layer is a phase change material, such as polyethylene wax (a polyolefin) Id. at paragraph [0029]. Zhang doesn't expressly state that the phase change material will fill the pores in the surface of the microporous substrate. Nonetheless, because it is a phase change material as those disclosed by Applicant to achieve this purpose and because Zhang discloses that its separator can perform a shutdown function the Office finds that this is an inherent property of Zhang. Zhang at paragraph [0020]. Finally, because Zhang is silent regarding any encapsulation of the phase change material, the Office finds that the phase change material particles of Zhang are unencapsulated.
Further regarding claim 8, the melting point of polyethylene wax is 100-150 C.
Further regarding claims 9-13 and 15, Zhang expressly states the batteries in which its separator
are provided include anode and cathode with the separator placed therebetween. Although Zhang
doesn't expressly disclose that the microporous separator is saturated wit an electrolyte, the person of
ordinary skill in the art at the time of invention would understand that this is a necessary element
inherently present in the battery because without it the battery would not function.
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.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang. Zhang is applied as described above. Zhang does not expressly disclose a thickness for its heat absorption layer. Nonetheless, Zhang discloses that the separator must sufficiently enable ionic transport between anode and cathode with the heat absorption layer being present to mitigate thermal propagation in the battery
during a short circuit or other overheating event. Id. at paragraph [0020] and [0023]. Thus, the thickness of the heat absorption layer of Zhang is found to be nothing more than an obvious design choice in arriving at a separator that sufficiently mitigates thermal propagation while maintaining excellent ion transport.
Claims 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Zhang in view of
2019/0245182 to Liao ("Liao"). Zhang is applied as described above. Although Zhang discloses providing ceramic coating on the microporous separator either as a composite with the heat absorption material or as an underlayer with the heat absorption layer applied on the ceramic, it does not state details of the ceramic layer. Liao is directed to similar microporous separators coated with ceramic teaching that such ceramic coatings are provided in order to improve electrolyte wettability of the separator thereby improving ion conductivity (permeability). Liao at Abstract and paragraph [0036]. It achieves this using as the ceramic alumina, silica, and/or boehmite having D50 ranging from 0.02 to 2 microns. Thus, the person of ordinary skill in the art in implementing the teachings of Zhang would have been motivated to use as ceramic particles alumina, silica, and/or boehmite having a D50 from 0.1-2 microns in order to arrive at a separator having excellent electrolyte wettability and permeability.
Allowable Subject Matter
Claims 6 and 14 are allowed for the reasons of record.
Response to Arguments
Applicant's arguments filed July 8, 2026, have been fully considered but they are not persuasive. Applicant first alleges that the inherency of pore-filling has not been established. The Office disagrees. The Office’s basis for inherency is the similarity of the materials of Zhang to those used by Applicant to achieve the recited property. That is, like Applicant, Zhang discloses the use of polyolefin phase change material having a melting point in the range of 100-150 applied to a polyolefin separator. This similarity of structure is sufficient to shift the burden to Applicant to establish that the claimed property is not present in Zhang despite it being present in Applicants substantially similar materials. MPEP 2112 (citing In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not."). Applicant provides no evidence rebutting this finding, instead making attorney argument that pore filling would prevent the battery from performing as intended. This argument, however, ignores the fact that the heat absorption material of Zhang is intended to prevent propagation of heat throughout the remainder of a battery by absorbing heat being generated in a region where battery operation has already failed via short circuit. See, e.g., Zhang at paragraphs [0036] and [0040].
Applicant next argues structural distinctions. First, Applicant alleges that Zhang merely discloses ceramic layers and heat absorption layers without disclosing the specific arrangement claimed. The Office disagrees: “the heat absorption layer and the ceramic layer can be combined into a single layer or combined layer.” Zhang at paragraph [0033] (further disclosing the ceramic layer on both surfaces of the porous substrate). Finally, Applicant alleges that Zhang does not sufficiently disclose that its phase change particles are unencapsulated. The Office disagrees. Zhang discloses polyethylene wax as a phase change material. It does not disclose any material to be combined with the polyethylene wax, nor does it disclose ensuring that the polyethylene wax is modified to become encapsulated or specifically obtained in an encapsulated form. Applicant provides no evidence that polyethylene wax is understood to those of ordinary skill in the art to be encapsulated, or that the person of ordinary skill in the art would otherwise have reason to read “polyethylene wax” as an encapsulated material. Thus, the fairest reading of the Zhang reference is that its phase change material is exactly what it says it is: polyethylene wax. Without disclosure of an encapsulating layer around that polyethylene wax, there is no basis in the record to find it to be anything other than unencapsulated.
Conclusion
THIS ACTION IS MADE FINAL. 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 WYATT P MCCONNELL whose telephone number is (571)270-7531. The examiner can normally be reached 9am to 5pm M-F.
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/WYATT P MCCONNELL/Examiner, Art Unit 1727
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