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 .
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 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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-9, 15 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (US 2020/0185676; hereinafter “Lee”) in view of Kim et al. (US 2022/0029244; hereinafter “Kim”).
In regard to claims 1-2, 4-9, Lee discloses a separator 100 for a rechargeable lithium battery ([0086]), the separator comprising a substrate (porous substrate 110); a heat resistant layer 120 on the substrate; and an adhesive layer 130 on the heat resistant layer, wherein: the heat resistant layer includes: inorganic particles which includes alumina (Al2O3), titania (TiO2), MgO, Mg(OH)2, or a combination thereof (see [0049]) as recited in claim 2, and a heat resistant binder (first binder resin; [0051]), the adhesive layer includes: a first adhesive binder (heat resistant layer can include a fluorinated binder resin and a non-fluorinated binder resin; [0062]) which is PVdF (fluorinated binder resin can include polyvinylidene fluoride; see [0065]), and a cyano group (-CN)-containing acrylic second adhesive binder (“the non-fluorinated polymer resin preferably includes a cyano group;” see [0067]). See Figure 1 and paragraphs [0046], [0062], [0065] and [0067].
Lee is silent in regard to wherein the heat resistant binder is salt-based.
Kim discloses a separator for a lithium secondary battery comprised of a separator and a heat-resistant layer (coating layer 30; see [0039]) which includes inorganic particles 2 and a heat-resistant binder which is comprised of an acrylic salt-based binder including nitrogen having a first structural unit of (meth)acrylic acid or meth(acrylate) which is represented by instant chemical formula 1 (see Chemical Formula 3 in [0054]), a second structural unit of (meth)acrylamide which is represented by instant chemical formula 4 (see Chemical Formula 1 in [0052] and a third structural unit of (meth)acrylamidosulfonic acid or a salt thereof as represented by instant chemical formulas 5, 6 and 7 (see Chemical Formulas 6, 4 and 5, respectively, in [0060]) as recited in claims 4-6. Kim teaches wherein the R, L, M, a, b and c variables are as recited in paragraphs [0053], [0055] and [0061]-[0062]. Kim teaches that the heat resistant binder can be prepared from a poly(acrylic acid-co-acrylamide-co-2-acrylamido-2-methylpropanesulfonic acid)sodium salt which meets the limitation of claim 7. Kim discloses wherein the coating layer can include an adhesive binder 1 which has a core-shell structure (see [0077]) and is swellable (see [0095]-[0099]) as recited in claim 8. Kim further discloses wherein the heat resistant layer includes a weight ratio of binder to inorganic particles of 1:20 to 1:40 which would necessarily include the weight percentages of 2.44 to 4.76 wt% of binder and 95.24 to 97.56 wt% of inorganic particles which are within the recited ranges of claim 9. See [0039], [0042], [0053], [0055], [0060]-[0062], [0077], [0095], [0099], [0113], [0115], [0117] and Figure 4.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the coating layer of Kim for the heat resistant layer of Lee as the layers are functionally equivalent as they are both coated on the substrate and would achieve predictable results. 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. __,__, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
In regard to claim 3, Lee discloses wherein the inorganic particles can have a diameter of “500 nm or less” and “100 nm or more” in [0048] which is viewed to capture the recited range of “about 100 nm to about 500 nm.”
Nonetheless, it would have been within the ambit of one of ordinary skill in the art before the effective filing date of the claimed invention to have determined an optimal or workable range of D50 particle diameter of the inorganic particles through routine experimentation and without the creation of any new or unexpected results. It is further noted that the specification does not provide criticality of the recited D50 particle diameter range. “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).
In regard to claim 15, Lee discloses wherein the non-fluorinated binder can include a structural unit of (meth)acrylic polymer or a (meth)acrylate, and a cyano group-containing structure. See [0067].
Lee is silent in regard to the further inclusion of (meth)acrylamidosulfonic acid or a salt thereof.
Kim discloses that (meth)acrylamidosulfonic acid or a salt thereof is useful as an additional structural unit with a structural unit of (meth)acrylic acid or a (meth)acrylate as the additional structural unit includes a bulky functional group which reduces the mobility of the copolymer to enhance the heat resistance of the separator. See [0045].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have further included the structural unit of Kim in the non-fluorinated binder composition of Kim for the purpose of adding a bulky functional group to increase the heat resistance of the binder.
In regard to claim 18, Lee discloses wherein the adhesive layer includes 1-20 wt% of the non-fluorinated binder with the remainder of the binder being the fluorinated binder, thus 99-80 wt%, which meets the recited range of claim 18.
In regard to claim 19, Lee discloses wherein the heat resistant layer 120 and the adhesive layer 130 are respectively on two opposite surfaces of the substrate 110. See Figure 1.
In regard to claim 20, Lee discloses a lithium secondary battery that includes a positive electrode, a negative electrode and a separator interposed between the negative and positive electrodes. See [0087].
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the combined separator as disclosed in the rejection of claim 1 above in a lithium rechargeable battery without any new or unexpected results.
Claims 10-14 are rejected under 35 U.S.C. 103 as being unpatentable over Lee in view of Kim as applied to claim 1 above and further in view of Song et al. (EP 2624333; hereinafter “Song”).
In regard to claims 10-14, Lee discloses wherein the PVdF first adhesive binder includes a co-polymer of hexafluoropropylene. See [0054].
Lee and Kim do not explicitly disclose the inclusion or absence of a COOH functional group nor is the crystallinity of the binder disclosed.
Song discloses a binder for a separator which includes inorganic particles for heat resistance, wherein the binder is made from poly(vinylidene-hexafluoropropylene) (PVdF-HFP) copolymer, thus not including a COOH functional group, and poly(vinylidene-hexafluoropropylene) including COOH as a functional group in a ratio of 1:9 (5g to 45g; see [0103], which is within the recited range of claim 14. See [0010]-[0014], [0038], [0045], and [0103].
Song is silent in regard to the crystallinity of the binders. However, it is noted that the criticality of the crystallinity of either components was not disclosed and it is well understood by one of ordinary skill in the art that PVDF is semi-crystalline. Therefore, it would have been within the ambit of one of ordinary skill in the art to have determined an optimum or workable range of crystallinity for both P(VdF-HFP) binder components through routine experimentation to deliver desirable properties and operation of the separator without creating any new or unexpected results.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the (PVdF-HFP) copolymer of Song for the PVdF first adhesive in the above combined separator of Lee and Kim for the purpose of increasing the adhesion to the current collector and increasing the rigidity of the layer to improve the thermal stability of the battery.
Claims 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Lee in view of Kim as applied to claims 1 or 15 above and further in view of Seo et al. (US 2017/0338461; hereinafter “Seo”).
In regard to claims 15-17, Lee and Kim are silent in regard to the specific compositions of claims 16-17. Additionally, this rejection is included in case it is viewed that claim 15 is not obviated by the above combination of Lee and Kim.
Seo discloses a separator 10 with a heat resistant layer 30 comprised of inorganic particles and an acryl-based copolymer including a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit and further include a non-cross-linkable binder in addition to the acryl-based copolymer such as polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP). Seo teaches that the structural unit of (meth)acrylate or (meth)acrylic acid can be represented by the instant chemical formulas 11-13 (see Chemical Formulas 3, 1 and 2, respectively, in [0045]), the structural unit of the cyano group-containing unit can be represented by the instant chemical formula 14, and the a sulfonate group-containing unit can be a (meth)acrylamidosulfonic acid which can be represented by the instant chemical formulas 15-17 (see Chemical formulas 7, 5 and 6, respectively, in [0054]). Seo teaches that the recited variables are equivalent and disclosed in [0046], [0051] and [0055]-[0056]. Seo teaches wherein the binder can be derived from poly(acrylic acid-co-acrylonitrile-co-2-acrylamido-2-methylpropane sulfonic acid) sodium salt which is equivalent to the limitation of claim 17. See [0044]-[0060], [0077]-[0078] and [0115].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the compositions of Seo for the binder of the heat resistant layer of the above combination of Lee and Kim as one of ordinary skill in the art would have looked to the prior art to determine appropriate compositions to use to form the binder as disclosed.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TIMOTHY C CLEVELAND whose telephone number is (571)270-5041. The examiner can normally be reached M-F 7:30 AM - 3:30 PM ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Claire Wang can be reached at (571) 270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/TIMOTHY C CLEVELAND/Primary Examiner, Art Unit 1774
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