DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 May 1, 2026, has been entered. Claims 1, 3, 5, and 13-15 are pending in the application.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1, 2, 5, and 13-15 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 1 recites “the binder has a bonding force of 2 gf/cm or more”. This limitation appears to contain new matter. Applicant references Figure 2 for support of the preceding limitation; however, Example 4 of Figure 2 appears to suggest a bonding force above 2.5 gf/cm, while Example 5 appears to suggest a bonding force of less than 3 gf/cm. In Example 8 of Figure 3, the bonding force is less than 4 gf/cm, and in Example 9, the bonding force is about 2 gf/cm. The Figures reasonably provide support for 2 gf/cm, but there does not appear to be support for the scope of the “or more” language, because the highest bonding force value supported by the Figures appears to be Example 8, which is less than 4 gf/cm. As presently claimed, the limitation of the bonding force in claim 1 reads on a binder that has a bonding force greater than 4 gf/cm, such as 6 gf/cm, 10 gf/cm, etc., which exceeds the scope of support set forth in the Figures.
Claims 2, 5, and 13-15 are rejected for being dependent upon a rejected base claim.
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.
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, 5, 13, 14, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over US 20040048154 A1 (Jung ‘154) in view of US 20190157665 A1 (Pope ‘665).
Regarding claim 1, Jung ‘154 teaches a positive electrode of a lithium secondary battery (an additive used in a positive electrode of a lithium-sulfur battery, wherein the additive physically and chemically interacts with a binder to enhance adhesion of the binder; [0023]) comprising:
a positive electrode active material (the positive electrode includes a positive active material including elemental sulfur, a sulfur-based compound, or a mixture thereof; [0027]),
a conductive material (the positive electrode includes a conductor, wherein the conductor is a conductive material, for example, a carbon-based material; [0027] – [0028]),
and a binder comprising a polymer comprising a carboxylate group wherein the polymer comprising the carboxylate group comprises poly(acrylic acid) (the polymer comprising a carboxylate group corresponds to the binder being polyacrylic acid in [0029] of Jung ‘154; see also [0016] of the published patent application, i.e., US 20220209237); and a cationic polymer (a polymer that is cationic; [0023]),
wherein a content of the cationic polymer is 5% by weight to 25% by weight based on a total weight of the binder (the positive electrode preferably includes 5 to 50 parts by weight of the additive based on 100 parts by weight of the binder, wherein the additive improves adhesion of the binder; [0030]),
wherein the polymer comprising the carboxylate group and the cationic polymer are present in a weight ratio of 85:15 to 93:7 (in example 2 of Jung ‘154, [0047] - [0049], the positive electrode includes 1 g of polyvinyl pyrrolidone and 0.1 g of polyethyleneimine, such that, the 1 g of polyvinyl pyrrolidone ([0029]) constituting the polymer comprising a carboxylate group and the 0.1 g of polyethyleneimine constituting the cationic polymer are present in a weight ratio of 91:9 because 1 g out of a total 1.1 g times 100% equates to about 91% for the polymer comprising the carboxylate group and 0.1 g out of a total 1.1 g times 100% equates to about 9% for the cationic polymer, which falls within the claimed range), and
wherein the positive electrode active material is present in the form of a sulfur-carbon composite (in example 1, carbon black and elemental sulfur were added to the mixed binder liquid and were distributed to prepare a composite slurry for the positive electrode of a lithium-sulfur battery; [0047]).
As set forth in MPEP 2144.05, 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)).
Therefore, prior to the effective filing date of the claimed invention, it would have been obvious to a person of ordinary skill in the art, to include the cationic polymer in an amount of 5% by weight to 25% by weight based on a total weight of the binder, to improve adhesion of the binder in the electrode of a lithium secondary battery, as taught by Jung ‘154.
Jung ‘154 discloses that polyethyleneimine is an example of the cationic polymer additive ([0023]), however, Jung ‘154 does not disclose that the cationic polymer comprises poly(diallyldimethylammonium chloride).
Pope ‘665 discloses a cathode for use in a lithium-sulfur (Li—S) battery comprising a graphene material (GM) ([0004]). The cathode also comprises a nitrogen-containing polymer (N-polymer) and sulfur (S) ([0004]). The N-polymer(s) include a high density of nitrogen-containing groups such as polyethyleneimine (PEI), poly (diallyl dimethyl ammonium chloride), or poly(vinylamine)hydrochloride ([0004]; [0025]; & [0026]).
Therefore, it would have been obvious to a person of ordinary skill in the art, prior to the effective filing date of the claimed invention, to select poly (diallyl dimethyl ammonium chloride) as the cationic polymer, as suggested by Pope ‘665, in the binder for the electrode of the lithium secondary battery, as taught by Jung ‘154, because the selection of a known material, which is based upon its suitability for its intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
Jung ‘154 in view of Pope ‘665 does not explicitly disclose that the binder has a bonding force of 2 gf/cm or more.
However, [0143] of the PG Pub (US 20220209237 A1) states that the positive electrodes of the examples comprising the binder produced by mixing a small amount of cationic polymer with the polymer including the carboxylate group have excellent positive electrode bonding force, as compared to the positive electrode of the comparative examples that do not contain the cationic polymer.
Likewise, Jung discloses that an additive improves adhesion of the binder by allowing an amount of the binder to decrease and allowing an amount of the positive active material to increase ([0030]). Thus, the lithium-sulfur battery exhibits high capacity ([0030]). However, excess additive prevents an increase in the amount of the positive active material, and hence limits capacity ([0030]). Therefore, Jung recognizes that a binder including a controlled amount of an additive (not in excess) for a lithium-sulfur battery has improved adhesion and high capacity. The binder may be polyacrylic acid, and the additive may be an additive which physically and chemically interacts with a binder to improve the adhesion of the binder ([0078]).
Therefore, in view of the disclosure of Jung and Pope, the claimed product would reasonably be expected to include a binder having a bonding force of 2 gf/cm or more, when a cationic polymer additive, such as polyethyleneimine or poly(diallyldimethylammonium chloride), is included in the binder comprising poly(acrylic acid) in a weight ratio of 91:9, because the addition of the additive in a small amount improves adhesion of the binder, i.e., bonding force of the binder is improved.
Regarding claim 5, Jung ‘154 teaches the binder for the electrode of the lithium secondary battery according to claim 1, wherein the cationic polymer has a weight average molecular weight of 3,000 to 1,000,000 (the N-polymer can have a molecular weight between about 100 daltons (DA) and about 10 MDa; for example, a polyethyleneimine dendrimer containing a large amount of branching with many end groups of primary amines can form the most interactions with both the graphene surface and the most active sites for bonding with polar lithium polysulfides (LiPSs); other amine-containing polymers, such as poly(dially dimethyl ammonium chloride), are suitable materials known to those skilled in the art; [0024] & [0026] of Pope ‘665).
Jung’ 154 discloses that the weight-average molecular weight of the polyethyleneimine is 20,000 to 150,000 ([0024]), but does not disclose poly(dially dimethyl ammonium chloride) with a weight-average molecular weight of 3,000 to 1,000,000.
Pope ‘665 discloses that the N-polymers, such as polyethyleneimine and poly(dially dimethyl ammonium chloride) can have a molecular weight between about 100 DA and about 10 MDa, but does not disclose the molecular weight as a weight average molecular weight.
Nevertheless, it would have been obvious to a person of ordinary skill in the art, prior to the effective filing date of the claimed invention, to select poly(dially dimethyl ammonium chloride) with a weight average molecular weight within the claimed range of 3,000 to 1,000,000, because amine-containing polymers, such as polyethyleneimine and poly(dially dimethyl ammonium chloride), having a molecular weight between about 100 DA and about 10 MDa, are used to mitigate the shuttle effect of LiPSs by interactions between nitrogen-containing groups and LiPS ([0026]), as suggested by Pope ‘665, in the positive electrode of the lithium secondary battery, as taught by Jung ‘154.
Further, the selection of a known material, which is based upon its suitability for its intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
Regarding claim 13, Jung ‘154 teaches the positive electrode for the lithium secondary battery according to claim 1, wherein a content of the binder is 2% by weight to 10% by weight based on a total weight of a base solid content included in the positive electrode for the lithium secondary battery (in example 1 of [0047] of Jung ‘154, the base solid content of the positive electrode includes 1 g of polyvinyl pyrrolidone, 0.05 g of polyethyleneimine, 2 g of carbon black, and 16 g of elemental sulfur, such that, the 1 g of polyvinyl pyrrolidone ([0029]) constituting the polymer comprising a carboxylate group together with the 0.05 g of polyethyleneimine constituting the cationic polymer is equal to 5.5% of the total weight of the solid content included in the positive electrode, because the binder makes up 1.05 g out of the total 19.05 g of base solid content).
As set forth in MPEP 2144.05, 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)).
Regarding claim 14, Jung ‘154 teaches the positive electrode for the lithium secondary battery according to claim 1, wherein the binder comprises the polymer comprising the carboxylate group and the cationic polymer, and a content of the cationic polymer is 0.1% by weight to 3% by weight based on a total weight of a base solid content included in the positive electrode for the lithium secondary battery (in example 1 of [0047] of Jung ‘154, the base solid content of the positive electrode includes 1 g of polyvinyl pyrrolidone, 0.05 g of polyethyleneimine, 2 g of carbon black, and 16 g of elemental sulfur, such that, the 0.05 g of polyethyleneimine constituting the cationic polymer is equal to 0.26% of the total weight of the solid content included in the positive electrode, because the cationic polymer makes up 0.05 g out of the total 19.05 g of base solid content).
As set forth in MPEP 2144.05, 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)).
Regarding claim 15, Jung ‘154 teaches a lithium secondary battery comprising the positive electrode (a lithium-sulfur battery having a positive electrode; [0036] of Jung ‘154) for the lithium secondary battery according to claim 1 (see the rejection of claim 10 above), a negative electrode (a negative electrode 12; [0036] of Jung ‘154), a separator interposed between them (a separator 13 interposed between the positive electrode 11 and the negative electrode 12; [0036] of Jung ‘154), and an electrolyte (an electrolyte; [0036] of Jung ‘154).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over US 20040048154 A1 (Jung ‘154) in view of US 20190157665 A1 (Pope ‘665) or Polycation Binders: An Effective Approach toward Lithium Polysulfide Sequestration in Li–S Batteries (Su 2017), and further in view of US 20170324094 A1 (Sugiyama ‘094).
Regarding claim 3, Jung ‘154 teaches the positive electrode of the lithium secondary battery according to claim 1, but does not specifically disclose that the polymer comprising the carboxylate group has a weight average molecular weight of 50,000 to 5,000,000.
Sugiyama ‘094 discloses a polymer compound for use as a binder (abstract). The polymer compound includes polyacrylic acid having a weight average molecular weight in a range of 50,000 to 1,500,000 ([0035] – [0036]).
Therefore, it would have been obvious to a person of ordinary skill in the art, prior to the effective filing date of the claimed invention, for the polymer comprising the carboxylate group (polyacrylic acid) in the binder, as taught by Jung ‘154, to have a weight average molecular weight of 50,000 to 1,500,000, which overlaps with the claimed range of claim 3 (50,000 to 5,000,000), as suggested by Sugiyama ‘094.
As set forth in MPEP 2144.05, 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)).
Response to Arguments
Applicant's arguments filed on May 1, 2026, have been fully considered.
Applicant argues that Jung does not disclose a weight ratio of 85:15 to 93:7, as required in amended claim 1. However, applicant’s argument is not persuasive. In example 2 of Jung, [0047] - [0049], the positive electrode includes 1 g of polyvinyl pyrrolidone and 0.1 g of polyethyleneimine, such that, the 1 g of polyvinyl pyrrolidone ([0029]) constituting the polymer comprising a carboxylate group and the 0.1 g of polyethyleneimine constituting the cationic polymer are present in a weight ratio of 91:9, because 1 g out of a total 1.1 g times 100% equates to about 91% for the polymer comprising the carboxylate group and 0.1 g out of a total 1.1 g times 100% equates to about 9% for the cationic polymer, which falls within the claimed range.
Applicant additionally argues that the applied references do not disclose the binder has a bonding force of 2 gf/cm or more, as required by amended claim 1. Moreover, applicant suggests that the claimed bonding force should not be reasonably expected from Jung, because Jung does not disclose a substantially similar product. However, applicant’s argument is not persuasive.
Jung does disclose the claimed weight ratio in Example 2, as discussed above. While Jung does not disclose that the additive, corresponding to the cationic polymer, may be poly(diallyldimethylammonium chloride), Jung discloses that the additive may be polyethyleneimine, which is a polymer containing primary, secondary, and tertiary amino nitrogen ([0023] – [0024]).
Pope discloses polymers with a high density of nitrogen-containing groups such as polyethyleneimine (PEI), poly (diallyl dimethyl ammonium chloride), or poly(vinylamine)hydrochloride, which are suitable for use in a cathode of a lithium-sulfur (Li—S) battery ([0004]; [0025]; & [0026]). Thus, a skilled artisan would have found it obvious to select poly(diallyldimethylammonium chloride) as the additive, corresponding to the binder containing a cationic polymer, instead of polyethyleneimine, because the selection of a known material, which is based upon its suitability for its intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
Therefore, Jung in view of Pope discloses a substantially similar product.
In particular, [0143] of the PG Pub (US 20220209237 A1) states that the positive electrodes of the examples comprising the binder produced by mixing a small amount of cationic polymer with the polymer including the carboxylate group have excellent positive electrode bonding force, as compared to the positive electrode of the comparative examples that do not contain the cationic polymer.
Likewise, Jung discloses that an additive improves adhesion of the binder by allowing an amount of the binder to decrease and allowing an amount of the positive active material to increase ([0030]). Thus, the lithium-sulfur battery exhibits high capacity ([0030]). However, excess additive prevents an increase in the amount of the positive active material, and hence limits capacity ([0030]). Therefore, Jung recognizes that a binder including a controlled amount of an additive (not in excess) for a lithium-sulfur battery has improved adhesion and high capacity. The binder may be polyacrylic acid, and the additive may be an additive which physically and chemically interacts with a binder to improve the adhesion of the binder ([0078]).
Therefore, in view of the disclosure of Jung and Pope, the claimed product would reasonably be expected to include a binder having a bonding force of 2 gf/cm or more, when a cationic polymer additive, such as polyethyleneimine or poly(diallyldimethylammonium chloride), is included in the binder comprising poly(acrylic acid) in a weight ratio of 91:9, because the addition of the additive improves adhesion of the binder, i.e., the bonding force of the binder is improved.
Applicant additionally argues that Examples 4 and 5 correspond to the claimed embodiments, have superior positive electrode bonding force, and produce unexpected results over Example 6, which has a weight ratio of 79:21. However, applicant’s arguments are not persuasive, because Jung discloses a weight ratio of 91:9, which falls within the claimed weight ratio of 85:15 to 93:7, as discussed above. Further, the bonding force limitation of claim 1 is not commensurate in scope with the Examples, because the scope of the binder having a bonding force of 2 gf/cm or more exceeds the highest bonding force value set forth in the Figures.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Quaternary ammonium cationic polymer as a superior bifunctional binder for lithium–sulfur batteries and effects of counter anion (Liao 2017) discloses the potential of a quaternary ammonium cationic polymer, polydiallyldimethylammonium (PDADMA-X, X = T, B, P, and Cl) with different counter anions (TFSI-, BF4-, PF6-, and Cl-, respectively) as a bifunctional binder with both strong binding and superior polysulfide trapping properties for the fabrication of sulfur cathodes with suppressed polysulfide shuttling in Li-S batteries (abstract). The PDADMA-X polymers bearing other counter anions can be easily obtained from commercially available, cheap PDADMA-Cl having a chloride counter anion by anion exchange (middle of column 1, page 627).
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/TAYLOR HARRISON KRONE/Examiner, Art Unit 1725
/NICOLE M. BUIE-HATCHER/Supervisory Patent Examiner, Art Unit 1725
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