Prosecution Insights
Last updated: October 02, 2026
Application No. 16/652,035

BINDER FOR LITHIUM ION BATTERIES, AND ELECTRODE AND SEPARATOR USING SAME

Final Rejection §103
Filed
Mar 28, 2020
Priority
Sep 29, 2017 — nonprovisional of PCTJP2017035626
Examiner
MARTIN, MATTHEW T
Art Unit
1728
Tech Center
1700 — Chemical & Materials Engineering
Assignee
The Japan Steel Works Ltd.
OA Round
9 (Final)
44%
Grant Probability
Moderate
10-11
OA Rounds
0m
Est. Remaining
83%
With Interview

Examiner Intelligence

Grants 44% of resolved cases
44%
Career Allowance Rate
266 granted / 599 resolved
-20.6% vs TC avg
Strong +38% interview lift
Without
With
+38.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 9m
Avg Prosecution
35 currently pending
Career history
601
Total Applications
across all art units

Statute-Specific Performance

§101
0.5%
-39.5% vs TC avg
§103
53.7%
+13.7% vs TC avg
§102
16.6%
-23.4% vs TC avg
§112
22.2%
-17.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 599 resolved cases

Office Action

§103
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 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. Claims 1, 4-9 & 22-25 are rejected under 35 U.S.C. 103 as being unpatentable over Masafumi (JP2002260663, see Machine Translation for citations) (Provided in Applicant’s IDS filed on March 28th, 2020) in view of Saito et al (“Cellulose Nanofibers Prepared by TEMP-Mediated Oxidation of Native Cellulose”) further in view of Hirano (US20150093625). Regarding Claim 1, Masafumi discloses a composite nonaqueous binder, comprising a matrix of a thermoplastic fluororesin and a cellulose nanofiber present in the matrix in a dispersed state, (cellulose fiber and binder suspended in solvent together with active material-[0024], cellulose fiber, with nano sizes, used in both electrodes- [0010], cellulose nanofiber used in conjunction with binder for the same purpose, therefore it is the examiner’s position that a cellulose nanofiber is part of the overall binder structure-[0024], binder includes PVdf- [0026], PVdF is thermoplastic-[0049]), Wherein the cellulose nanofiber is a cellulose having a fiber diameter of 0.002 um or more and 1 um or less (thickness of cellulose fibers can be from 0.01 to 50 um - [0010], preferable thickness of the cellulose fibers is 0.1 or more and 1 um or less-[0017]), a fiber length of 0.5 um or more and 1 mm or less (preferred length range is 0.1 um to 500 um-[0020]) and an aspect ratio, fiber length of the cellulose nanofiber/fiber diameter of the cellulose nanofiber, of 2 or more and 100,000 or less (ratio of length/thickness is more than 5 times-[0011], the most preferred range for this ratio is 10 to 50-[0018]). Masafumi does not directly disclose wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic resin. Masafumi discloses cellulose fibers present in the electrode, where the electrode active material, the cellulose fiber, the conductive agent and the binder are mixed together with a solvent to create the electrode mixture slurry ([0024]). Masafumi further discloses that the positive electrode active material and cellulose nanofiber can be formed into a pellet together with the conductive agent and a binder ([0024]). Masafumi further discloses wherein the binder has a wt% of at least double the cellulose nanofiber ([0024]). Masafumi further teaches that the cellulose fibers are optimized to achieve a uniform distribution of the cellulose fibers in the electrode ([0018],[0036]). Therefore it is the examiner’s position that because the cellulose fibers of Masafumi are uniformly mixed with the binder, made of thermoplastic resin, to make the positive electrode active material mixture, that Masafumi discloses wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic resin. Therefore it would be obvious to one of ordinary skill in the art using the disclosure of Masafumi to have the cellulose nanofibers present in a dispersed state in the thermoplastic resin. Masafumi is silent to the cellulose nanofiber comprises a cellulose nanofiber subjected to polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. Saito discloses a TEMPO-Mediated Oxidation of native cellulose for cellulose nanofibers (Introduction). Saito further discloses wherein this method allows for the removal of hydroxyl groups with carboxyl groups (Introduction). Saito teaches that this replacement allows for improved stable dispersion states of the cellulose nanofibers (TEM Observation of the TEMP-Oxidized cellulose Fibrils). The examiner notes that applicant is claiming a product (composite nonaqueous binder) and therefore the limitation is a product by process limitation, and because Saito provides motivation to replace the hydroxyl groups with carboxyl groups, specifically teaching that this replacement provides improved mechanical strength and improved thermal properties, that it would be obvious to one of ordinary skill in the art to modify the cellulose nanofibers of Masafumi with the teachings of Saito to have the cellulose nanofiber comprising a cellulose nanofiber subjected to polybasic acid semiesterification treatment to replace some of hydroxoyl groups with carboxyl groups. Therefore, it would be obvious to one of ordinary skill in the art to modify the cellulose nanofiber of Masafumi with the teachings of Saito to have a cellulose nanofiber that is subjected polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. This modified structure would yield the expected results of improved mechanical strength and improved thermal properties. Masafumi further discloses wherein when the total amount of solid contents of the cellulose nanofiber and the thermoplastic fluororesin is taken as 100 mass%, the cellulose nanofiber is contained in an amount of 5 mass% or more and 50 mass% or less, and the thermoplastic fluroresin is contain in an amount of 50 mass% or more and 95 mass% or less (the blending ratios of the cellulose fiber in regards to the overall positive electrode is 0.1 to 5 wt% and the binder is preferably 80 to 95% of the positive electrode, and therefore these ranges substantially overlap the instant claim range of when 100 mass% is equal to the total mass of the cellulose nanofiber and thermoplastic fluroresin together, [0023],[0027][0043]). Masafumi does not directly disclose wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic fluororesin using a dispersion liquid. Hirano discloses a separator for a lithium-ion battery ([002]) that Is formed of cellulose fibers and thermoplastic fibers where the cellulose fibers and thermoplastic resin are mixed ([006]). Hirano further discloses wherein the thermoplastic fibers can be formed from resin ([0033]). Hirano further discloses that a dispersion liquid is used to mix the cellulose fibers and thermoplastic fibers ([0040], [0057]). Hirano teaches that this structure provides a separator that sufficiently prevents occurrences of internal short circuits ([007]). Therefore, it would be obvious to one of ordinary skill in the art to modify Masafumi with the teachings of Hirano to have wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic fluororesin using a dispersion liquid. This modified structure would yield the expected result of providing a separator that sufficiently prevents occurrences of internal short circuits. Masafumi does not directly disclose wherein an aspect ratio of the cellulose nanofiber is 110 or more and 100,000 or less. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985) (Court held as proper a rejection of a claim directed to an alloy of "having 0.8% nickel, 0.3% molybdenum, up to 0.1% iron, balance titanium" as obvious over a reference disclosing alloys of 0.75% nickel, 0.25% molybdenum, balance titanium and 0.94% nickel, 0.31% molybdenum, balance titanium. "The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties."). See also Warner-Jenkinson Co., Inc. v. Hilton Davis Chemical Co., 520 U.S. 17, 41 USPQ2d 1865 (1997) (under the doctrine of equivalents, a purification process using a pH of 5.0 could infringe a patented purification process requiring a pH of 6.0-9.0); Masafumi further discloses wherein the cellulose nanofiber can have a thickness of cellulose fibers from 0.01 to 50 um ([0010]) and a fiber length of length range is 0.1 um to 500 um ([0020]) which provides an overall aspect ratio range of 50,000 to 10, which overlaps the instant claim range of 110 to 100,000. Therefore, it would be obvious to one of ordinary skill in the art using the disclosure of Masafumi to have wherein an aspect ratio of the cellulose nanofiber is 110 or more and 100,000 or less. Regarding Claim 4, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi is silent to the cellulose nanofiber comprises a cellulose nanofiber subjected to ethylene oxide addition treatment or propylene oxide addition treatment. Saito discloses a propylene oxide addition treatment (secondary propylene oxide addition treatment-[0018], example 1-[0048]). Saito teaches that this treatment allows for the cellulose nanofibers to have improved mechanical strength and improved thermal properties ([0016]). Therefore, it would be obvious to one of ordinary skill in the art to modify the cellulose nanofiber of Masafumi with the teachings of Saito to have a cellulose nanofiber that is subjected to ethylene oxide addition treatment or propylene oxide addition treatment. This modified structure would yield the expected results of improved mechanical strength and improved thermal properties. Regarding Claim 4, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi is silent to the cellulose nanofiber comprises a cellulose nanofiber subjected to ethylene oxide addition treatment or propylene oxide addition treatment. Saito discloses a propylene oxide addition treatment (secondary propylene oxide addition treatment-[0018], example 1-[0048]). Saito teaches that this treatment allows for the cellulose nanofibers to have improved mechanical strength and improved thermal properties ([0016]). Therefore, it would be obvious to one of ordinary skill in the art to modify the cellulose nanofiber of Masafumi with the teachings of Saito to have a cellulose nanofiber that is subjected to ethylene oxide addition treatment or propylene oxide addition treatment. This modified structure would yield the expected results of improved mechanical strength and improved thermal properties. Regarding Claim 5, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses wherein the thermoplastic resin comprises polyvinylidene fluoride ([0026]). Regarding Claim 6, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses wherein the thermoplastic fluororesin is dissolved in N-methyl-2-pyrrolidone, and the cellulose nanofibers are dispersed in N-methyl-2-pyrrolidone ([0074]), Wherein when the total mass of the cellulose nanofibers, the thermoplastic fluororesin, and the N-methyl-2-pyrrolidone in the binder is taken as 100 mass%, a total amount of solid contents of the cellulose nanofibers and the thermoplastic fluororesin is 3 mass% or more and 30 mass% or less (for positive electrode-[0074],for negative electrode-[0075]). Regarding Claim 7, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses an electrode comprising the binder according to claim 1 (binder according to claim 1 is disclosed by Masafumi as shown above in claim 1 rejection, both positive and negative electrode contain the composite binder of claim 1,[0027],[0040],[0074-0075]). Regarding Claim 8, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi does not directly disclose the use of a polymer gel. However, Masafumi discloses wherein the electrode of claim 7, comprises a polymer gel electrolyte comprising a lithium hexafluorophosphate, a cyclic carbonate, and a chain carbonate, wherein the polymer gel is a composite cellulose nanofiber (electrode group impregnated with non-aqueous electrolyte, and then plasticized to form gel-like nonaqueous electrolyte-[0049], electrolyte includes a nonaqueous solvent, a lithium salt and a polymer-[0049], where the solvent includes a combination of a cyclic carbonate and a chain carbonate-[0050-0051], and the lithium salt is lithium hexafluorophosphate- [0052], cellulose fibers in electrode absorb the non-aqueous electrolyte-[0017]). Therefore, it would be obvious to one of ordinary skill in the art using the disclosure of Masafumi to have an electrode that comprises a polymer gel comprising a lithium hexafluorophosphate, a cyclic carbonate, and a chain carbonate, wherein the polymer gel is a composite cellulose nanofiber. Regarding Claim 9, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses wherein the electrode of claim 7, comprises a Li-containing active substance ([003], positive electrode active material containing Li-[0015]). Regarding Claim 22, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi does not directly disclose wherein the dispersion liquid is NMP. Hirano discloses wherein the dispersion liquid can be NMP ([0057]). Therefore, it would be obvious to one of ordinary skill in the art to modify Masafumi with the teachings of Hirano to have wherein the dispersion liquid can be NMP. This modified structure would yield the expected result of providing a separator that sufficiently prevents occurrences of internal short circuits. Regarding Claim 23, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses wherein when the total amount of solid contents of the cellulose nanofiber and the thermoplastic fluororesin is taken as 100 mass%, the cellulose nanofiber is contained in an amount of 5 mass% or more and 50 mass% or less, and the thermoplastic fluroresin is contain in an amount of 50 mass% or more and 95 mass% or less (the blending ratios of the cellulose fiber in regards to the overall positive electrode is 0.1 to 5 wt% and the binder is preferably 80 to 95% of the positive electrode, and therefore these ranges substantially overlap the instant claim range of when 100 mass% is equal to the total mass of the cellulose nanofiber and thermoplastic fluroresin together, [0023],[0027][0043]). Regarding Claim 24, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi is silent to the cellulose nanofiber comprises a cellulose nanofiber subjected to polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. Saito discloses a TEMPO-Mediated Oxidation of native cellulose for cellulose nanofibers (Introduction). Saito further discloses wherein this method allows for the removal of hydroxyl groups with carboxyl groups (Introduction). Saito teaches that this replacement allows for improved stable dispersion states of the cellulose nanofibers (TEM Observation of the TEMP-Oxidized cellulose Fibrils). The examiner notes that applicant is claiming a product (composite nonaqueous binder) and therefore the limitation is a product by process limitation, and because Saito provides motivation to replace the hydroxyl groups with carboxyl groups, specifically teaching that this replacement provides improved mechanical strength and improved thermal properties, that it would be obvious to one of ordinary skill in the art to modify the cellulose nanofibers of Masafumi with the teachings of Saito to have the cellulose nanofiber comprising a cellulose nanofiber subjected to polybasic acid semiesterification treatment to replace some of hydroxoyl groups with carboxyl groups. Therefore, it would be obvious to one of ordinary skill in the art to modify the cellulose nanofiber of Masafumi with the teachings of Saito to have a cellulose nanofiber that is subjected polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. This modified structure would yield the expected results of improved mechanical strength and improved thermal properties. Regarding Claim 25, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi further discloses wherein the binder according to claim 1 is for an electrode or a separator wherein the lithium ion battery comprises an electrode active substance layer, the binder (binder according to claim 1 is disclosed by Masafumi as shown above in claim 1 rejection, both positive and negative electrode contain the composite binder of claim 1,[0027],[0040],[0074-0075]), and an electrolytic solution comprising a lithium hexafluorophosphate and an aprotic carbonate ([0052], [0050]). Claim(s) 10-14 are rejected under 35 U.S.C. 103 as being unpatentable over Masafumi (JP2002260663, see Machine Translation for citations) (Provided in Applicant’s IDS filed on March 28th, 2020) in view of Saito et al (“Cellulose Nanofibers Prepared by TEMP-Mediated Oxidation of Native Cellulose”) further in view of Hirano (US20150093625) further in view of Hirano’ (US20160156008) (Provided in Applicant’s IDS filed on March 28th, 2020). Regarding Claim 10, Masafumi in view of Saito further in view of Hirano discloses the limitations as set forth above. Masafumi disclose a separator but does not disclose the separator having the same binder as claim 1. Hirano’ disclose a separator for a secondary battery ([0011]) where the separator is made of cellulose fibers and fluororesin particles ([0029]). Hirano further discloses wherein the separator can include thermoplastic resin fibers ([0029]), and where the fluoresin particles can include PVdF ([0034]). Hirano’ teaches that the inclusion of these compounds allows for satisfactory air permeability ([008]), which in turn improves ion conductivity ([0011]). Therefore, it would be obvious to one of ordinary skill in the art to modify the separator of Masafumi with the teachings of Hirano to have a separator with the same binder as claim 1. This modified structure would yield the expected result of improved ion conductivity. Regarding Claim 11, Masafumi in view of Saito further in view of Hirano further in view of Hirano’ discloses the limitations as set forth above. Masafumi in view of Hirano discloses the same binder of claim 1, and claim 7 into the separator. Masafumi discloses a polymer gel electrolyte comprising a lithium hexafluorophosphate, a cyclic carbonate, and a chain carbonate, wherein the polymer gel is a composite cellulose nanofiber (electrode group impregnated with non-aqueous electrolyte, and then plasticized to form gel-like nonaqueous electrolyte-[0049], electrolyte includes a nonaqueous solvent, a lithium salt and a polymer-[0049], where the solvent includes a combination of a cyclic carbonate and a chain carbonate-[0050-0051], and the lithium salt is lithium hexafluorophosphate- [0052], cellulose fibers in electrode absorb the non-aqueous electrolyte-[0017]). However, Masafumi does not disclose the use of this electrolyte in the separator. Hirano’ discloses a Secondary battery with a nonaqueous electrolyte that has a separator with excellent electrolyte retention ([008]). Hirano’ teaches that this structure allows for satisfactory air permeability ([008]), which in turn improves ion conductivity ([0011]). Therefore, it would be obvious to one of ordinary skill in the art using the disclosure of Masafumi in view of Hirano to have a separator that comprises a polymer gel comprising a lithium hexafluorophosphate, a cyclic carbonate, and a chain carbonate, wherein the polymer gel is a composite cellulose nanofiber. This modified structure would yield the expected results of improved ion conductivity. Regarding Claim 12 & 13, Masafumi in view of Saito further in view of Hirano further in view of Hirano’ discloses the limitations as set forth above. Masafumi further discloses a lithium ion battery comprising the electrode of claim 7 and the separator of claim 10, wherein the separator is integrated with an electrode in the battery (positive and negative electrode are laminated with separator inbetween them-[0063]), and wherein the separator is bonded and integrated with the electrode. Although, Masafumi does not directly discloses wherein the binder contained in the separator is what integrates the separator with the electrode, because Masafumi in view of Hirano discloses a structure with integrated electrodes with a separator, all which share the same binder composition, therefore it would be obvious to one of ordinary skill in the art to modify the battery of Masafumi with the teachings of Hirano to have the separator integrated and bonded with the electrode through the binder contains in the electrode. This modified structure would yield the expected results of improved ion conductivity. Regarding Claim 14, Masafumi in view of Saito further in view of Hirano further in view of Hirano’ discloses the limitations as set forth above. Masafumi does not directly discloses the use of the battery of claim 12 being used in an electrical device. However Masafumi teaches that various electronic devices use secondary batteries as their power source ([002]). Therefore, it would be obvious to one of ordinary skill in the art using Masafumi’s disclosure with the teachings of Hirano to have the battery of claim 12 in an electrical device. Response to Arguments Applicant's arguments filed April 17th, 2026 have been fully considered but they are not persuasive. Applicant argues that Masafumi teaches away from the claimed aspect ratio. Masafumi discloses wherein the cellulose nanofiber is a cellulose having a fiber diameter of 0.002 um or more and 1 um or less (thickness of cellulose fibers can be from 0.01 to 50 um - [0010], preferable thickness of the cellulose fibers is 0.1 or more and 1 um or less-[0017]), a fiber length of 0.5 um or more and 1 mm or less (preferred length range is 0.1 um to 500 um-[0020]) and an aspect ratio, fiber length of the cellulose nanofiber/fiber diameter of the cellulose nanofiber, of 2 or more and 100,000 or less (ratio of length/thickness is more than 5 times-[0011], the most preferred range for this ratio is 10 to 50-[0018]). Therefore it is the examiner’s position that Masafumi does not teach away from the claimed aspect ratio. Applicant further argues that the “product-by process” rejection is not appropriate because the structure that is implied by the “process” of the instant creates a different structure than the prior art. The applicant states that the structural properties are not present in the prior art. The examiner notes that the claim language only requires that “a cellulose nanofiber subjected to polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups”. Masafumi is silent to the cellulose nanofiber comprises a cellulose nanofiber subjected to polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. Saito discloses a TEMPO-Mediated Oxidation of native cellulose for cellulose nanofibers (Introduction). Saito further discloses wherein this method allows for the removal of hydroxyl groups with carboxyl groups (Introduction). Saito teaches that this replacement allows for improved stable dispersion states of the cellulose nanofibers (TEM Observation of the TEMP-Oxidized cellulose Fibrils). The examiner notes that applicant is claiming a product (composite nonaqueous binder) and therefore the limitation is a product by process limitation, and because Saito provides motivation to replace the hydroxyl groups with carboxyl groups, specifically teaching that this replacement provides improved mechanical strength and improved thermal properties, that it would be obvious to one of ordinary skill in the art to modify the cellulose nanofibers of Masafumi with the teachings of Saito to have the cellulose nanofiber comprising a cellulose nanofiber subjected to polybasic acid semiesterification treatment to replace some of hydroxoyl groups with carboxyl groups. Therefore, it would be obvious to one of ordinary skill in the art to modify the cellulose nanofiber of Masafumi with the teachings of Saito to have a cellulose nanofiber that is subjected polybasic acid semi-esterification treatment to replace some of hydroxyl groups with carboxyl groups. This modified structure would yield the expected results of improved mechanical strength and improved thermal properties. Therefore, absent claim language defining the structural properties created by the “acid-esterification” process, applicant’s arguments regarding the structural differences in the TEMPO oxidation and acid semi-esterification are not commensurate in scope with the claim language. Applicant further argues that the prior art does not teach or disclose wherein “the cellulose nanofibers are represent in a dispersed state in the thermoplastic fluororesin using a dispersion liquid” The examiner notes that Masafumi discloses cellulose fibers present in the electrode, where the electrode active material, the cellulose fiber, the conductive agent and the binder are mixed together with a solvent to create the electrode mixture slurry ([0024]). Masafumi further discloses that the positive electrode active material and cellulose nanofiber can be formed into a pellet together with the conductive agent and a binder ([0024]). Masafumi further discloses wherein the binder has a wt% of at least double the cellulose nanofiber ([0024]). Masafumi further teaches that the cellulose fibers are optimized to achieve a uniform distribution of the cellulose fibers in the electrode ([0018],[0036]). Therefore Masafumi discloses wherein the cellulose nanofibers are present in a dispersed state. However, Masafumi does not directly disclose wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic fluororesin using a dispersion liquid. Hirano discloses a separator for a lithium-ion battery ([002]) that Is formed of cellulose fibers and thermoplastic fibers where the cellulose fibers and thermoplastic resin are mixed ([006]). Hirano further discloses wherein the thermoplastic fibers can be formed from resin ([0033]). Hirano further discloses that a dispersion liquid is used to mix the cellulose fibers and thermoplastic fibers ([0040], [0057]). Hirano teaches that this structure provides a separator that sufficiently prevents occurrences of internal short circuits ([007]). The examiner notes that Hirano is only brought in to teach that the same thermoplastic fibers formed from cellulose can be dispersed using a dispersion liquid. The structural differences of Hirano to the instant claim language, are not present in the claim language. Therefore applicant’s arguments are not commensurate in scope with the claim language. Therefore, it would be obvious to one of ordinary skill in the art to modify Masafumi with the teachings of Hirano to have wherein the cellulose nanofibers are present in a dispersed state in the thermoplastic fluororesin using a dispersion liquid. This modified structure would yield the expected result of providing a separator that sufficiently prevents occurrences of internal short circuits. 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 ANKITH R SRIPATHI whose telephone number is (571)272-2370. The examiner can normally be reached Monday - Friday: 7:30 am - 5:00pm. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matthew Martin can be reached at 571-270-7871. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ANKITH R SRIPATHI/Examiner, Art Unit 1728 /MATTHEW T MARTIN/Supervisory Patent Examiner, Art Unit 1728
Read full office action

Prosecution Timeline

Show 22 earlier events
Apr 15, 2025
Response Filed
Jul 30, 2025
Final Rejection mailed — §103
Oct 29, 2025
Response after Non-Final Action
Dec 10, 2025
Request for Continued Examination
Dec 11, 2025
Response after Non-Final Action
Dec 17, 2025
Non-Final Rejection mailed — §103
Apr 17, 2026
Response Filed
Jul 28, 2026
Final Rejection mailed — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12592409
APPARATUS FOR A PRISMATIC BATTERY CELL WITH BUILT-IN SPRINGS
3y 6m to grant Granted Mar 31, 2026
Patent 12548860
ELECTRODE PLATE FOR SECONDARY CELL, AND SECONDARY CELL USING SAME
4y 8m to grant Granted Feb 10, 2026
Patent 12494547
APPARATUS FOR MANUFACTURE OF ELECTRODE ASSEMBLY AND ELECTRODE ASSEMBLY MANUFACTURED BY THE SAME
3y 3m to grant Granted Dec 09, 2025
Patent 12394802
POWER STORAGE CELL
1y 5m to grant Granted Aug 19, 2025
Patent 11271162
FULLERENE DERIVATIVES, AND ORGANIC PHOTOELECTRIC DEVICE, IMAGE SENSOR, AND ELECTRONIC DEVICE INCLUDING THE SAME
2y 3m to grant Granted Mar 08, 2022
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

10-11
Expected OA Rounds
44%
Grant Probability
83%
With Interview (+38.5%)
3y 9m (~0m remaining)
Median Time to Grant
High
PTA Risk
Based on 599 resolved cases by this examiner. Grant probability derived from career allowance rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month