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 .
Response to Amendment
The amendments filed 1/30/2026 have been entered. Claim 19 and 31 are amended and Claim 25 is cancelled.
Support for the amendments can be found in Table 2 pf the instant specification.
Claims 19, 22-24, and 26-31 are pending, of which Claims 31-36 are withdrawn.
Response to Arguments
On pages 7 and 8, Applicant argues unexpected results when the content of the TFE polymer is between 1 and 7.5 wt%. Tables 1 and 2 are provided as evidence: Examples 1-4, which comprise the TFE polymer in the claimed range, have a good tensile strength while maintaining a higher conductivity compared to Examples 5-7, which have a higher wt% of TFE polymer, and Comparative Examples 1-3, which have a lower wt% of TFE. Examples 5-7 have good tensile strength but low conductivity and Comparative Examples 1-3 have high conductivity but low tensile strength. Examiner notes that the exact tensile strengths of each example are not provided.
However, Burchardt (US 20080096061 A1), which teaches the use of PTFE as a binder in an electrode. Burchardt teaches that PTFE in an amount between 5 wt% and 20 wt% establishes a sufficiently high mechanical stability without reducing ionic conductivity.
Although Burchardt is directed to a metal-air battery electrode rather than a free-standing electrolyte film, it has been held that known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art (See MPEP 2143 F).
In this case, both Burchardt and the present invention use TFE polymers as a binder to increase mechanical properties (Burchardt: 0061; instant specification: Summary of the Invention). Burchardt teaches that PTFE used as a binder (which is a TFE polymer) in an overlapping amount as the present invention (5-20 wt% vs. 1-7.5 wt%) provides the same benefits as the present invention (sufficiently high mechanical stability without reducing ionic conductivity). Therefore, one of ordinary skill in the art would not find the results disclosed in Tables 1 and 2 to be new or unexpected as, “where 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” and “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (See MPEP 2144.05 II. A.).
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.
Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li (CN 105489931 A, machine translation provided) in view of Lee (US 20160336618 A1), Bankaitis (US 20150062779 A1, cited in 2/21/23 IDS), and Burchardt (US 20080096061 A1), and as evidenced by AoKeray (What are the FEP characteristics of polyfluoroethylene propylene (FEP)?).
Regarding Claim 19, Li teaches a method of preparing an electrolyte layer/film comprising the steps of mixing a sulfide-based electrolyte and a binder (step a) and then pressing the mixture into a foil to obtain the electrolyte layer/film (step b) (0028, 0053). The binder contains at least one tetrafluoroethylene (TFE) (co)polymer (0032). The mixing step involves fully mixing, which is equivalent to homogenizing, the sulfide-based electrolyte and the binder containing at least one TFE (co)polymer to obtain a mixed dry powder (step a1) and blending/grinding the mixed dry powder into a viscous powder, which is equivalent to a paste, (step a2) to fibrillate/fiberize the PTFE (0028, 0053, 0061-0062). The electrolyte viscous powder/paste is pressed into a foil/film at a temperature of between 60°C and 200°C (0028), which can specifically be 150°C (0063). 150°C falls within the claimed range of 30°C to 150°C.
Li does not teach that the electrolyte layer/film is pressed by calendaring or extruding, disclose the temperatures of the mixing/homogenizing (a1) or grinding/blending (a2), or disclose the crystallinity of the at least one TFE (co)polymer.
Lee teaches that extruding is a known method to form a solid electrolyte sheet/film (0182).
Li and Lee are considered analogous to the claimed invention as they relate to the same field of endeavor, mainly solid electrolyte sheets/films.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have modified the pressing step of Li to be extruding as Lee teaches it as a known method for forming a solid electrolyte film and would lead to nothing more than the predictable results of a solid electrolyte sheet/film being formed. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. (see MPEP § 2143, B.).
Modified Li does not disclose the temperatures of the mixing/homogenizing (a1) or grinding/blending (a2) or disclose the crystallinity of the at least one TFE (co)polymer.
Bankaitis teaches the use of PTFE as a binder in an electrode. Bankaitis teaches that a PTFE mixing step, which is equivalent to the homogenizing step of the claimed invention (a1) and the mixing step of Li, conducted at temperatures lower than 19°C allows for fibrillation to be avoided during the mixing/homogenizing (0033) and results in a powder that can be easily fed into a mill or extruder (0034) for more effective fibrillation (0031).
Bankaitis also teaches that a fibrillation step, which is equivalent to the blending step (a2) of the claimed invention or the grinding step of modified Li (which causes the PTFE to fiberize/fibrillate), can be conducted at a temperature of at least 25°C, e.g., at least 30°C (0041). This would overlap the claimed range of 30°C or higher.
Although Bankaitis is directed towards an electrode rather than electrolyte film, the teachings regarding the temperature of PTFE would still be applicable to any application that uses PTFE as a binder. Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art. (see MPEP § 2143, F.).
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 modified the mixing/homogenization (a1) temperature of modified Li to be lower than 19°C as taught by Bankaitis in order to avoid fibrillation during the step and allow for more effective fibrillation later.
It would also have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the grinding/blending (a2) temperature of modified Li to be above 25°C as taught by Bankaitis as it is a known temperature for PTFE fibrillation and would result in nothing more than a grinding/blending step conducted at a temperature suitable for PTFE fibrillation. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. (see MPEP § 2143, B.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have routinely selected the overlapping portions of the disclosed grinding/blending/fibrillation temperature ranges as selection of overlapping portions of ranges has been held to be a prima facie case of obviousness (see MPEP 2144.05).
Bankaitis also teaches that the PTFE can be crystalline (0032), which displays a well-ordered, hexagonal crystal structure below about 19°C (0032) (step a1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the at least one TFE (co)polymer of modified Li to be crystalline PTFE as Bankaitis teaches it as a suitable form of PTFE for a binder and the simple substitution of one known element for another is likely to be obvious when predictable results are achieved (see MPEP 2143 B).
Additionally, it would be obvious to one of ordinary skill in the art that the Amorphous Index of the crystalline PTFE of modified Li would satisfy the claimed Amorphous Index (less than or equal to 0.22) as the Amorphous Index measures the degree of amorphousness of the material (higher value means more amorphousness) and crystalline PTFE would have low amorphousness (lower Amorphous Index value) as it is crystalline. Applicant is invited to provide evidence showing that the crystalline PTFE of modified Li would not have an Amorphous Index less than or equal to 0.22.
Li teaches that the binder (TFE polymer) can be added in an amount from 1-10 parts by mass/weight (0053), which overlaps the claimed range of 1.0 to 7.5 wt%.
Burchardt teaches the use of PTFE as a binder in an electrode. Burchardt further teaches that PTFE in an amount between 5 wt% and 20 wt% establishes a sufficiently high mechanical stability without reducing ionic conductivity, which also overlaps the claimed range of 1.0 to 7.5 wt%.
Although Burchardt is directed to a metal-air battery electrode rather than a free-standing electrolyte film, it has been held that known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art (See MPEP 2143 F).
In this case, both Burchardt and modified Li use PTFE as a binder (Burchardt: 0061; Li: 0015) and the benefits disclosed by Burchardt regarding the PTFE binder amount (high mechanical stability without reducing ionic conductivity) in an electrode would also be beneficial in a free-standing electrolyte film.
Therefore, it would have been obvious to one of ordinary skill in the art to include the PTFE binder of modified Li in the amount taught by Burchardt in order to provide high mechanical stability without reducing ionic conductivity.
It would also have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have routinely selected the overlapping portions of the disclosed ranges as selection of overlapping portions of ranges has been held to be a prima facie case of obviousness (see MPEP 2144.05).
Claim(s) 19 and 26-28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li (CN 105489931 A, machine translation provided) in view of Lee (US 20160336618 A1) and Bankaitis (US 20150062779 A1, cited in 2/21/23 IDS), and as evidenced by AoKeray (What are the FEP characteristics of polyfluoroethylene propylene (FEP)?).
Regarding Claim 19, Li teaches a method of preparing an electrolyte layer/film comprising the steps of mixing a sulfide-based electrolyte and a binder (step a) and then pressing the mixture into a foil to obtain the electrolyte layer/film (step b) (0028, 0053). The binder contains at least one tetrafluoroethylene (TFE) (co)polymer (0032) added in an amount from 1-5 parts by mass/weight (0053). This falls within the claimed range of 1.0 to 7.5 wt%. The mixing step involves fully mixing, which is equivalent to homogenizing, the sulfide-based electrolyte and the binder containing at least one TFE (co)polymer to obtain a mixed dry powder (step a1) and blending/grinding the mixed dry powder into a viscous powder, which is equivalent to a paste, (step a2) to fibrillate/fiberize the PTFE (0028, 0053, 0061-0062). The electrolyte viscous powder/paste is pressed into a foil/film at a temperature of between 60°C and 200°C (0028), which can specifically be 150°C (0063). 150°C falls within the claimed range of 30°C to 150°C.
Li does not teach that the electrolyte layer/film is pressed by calendaring or extruding, disclose the temperatures of the mixing/homogenizing (a1) or grinding/blending (a2), or disclose the crystallinity of the at least one TFE (co)polymer.
Lee teaches that extruding is a known method to form a solid electrolyte sheet/film (0182).
Li and Lee are considered analogous to the claimed invention as they relate to the same field of endeavor, mainly solid electrolyte sheets/films.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have modified the pressing step of Li to be extruding as Lee teaches it as a known method for forming a solid electrolyte film and would lead to nothing more than the predictable results of a solid electrolyte sheet/film being formed. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. (see MPEP § 2143, B.).
Modified Li does not disclose the temperatures of the mixing/homogenizing (a1) or grinding/blending (a2) or disclose the crystallinity of the at least one TFE (co)polymer.
Bankaitis teaches the use of PTFE as a binder in an electrode. Bankaitis teaches that a PTFE mixing step, which is equivalent to the homogenizing step of the claimed invention (a1) and the mixing step of Li, conducted at temperatures lower than 19°C allows for fibrillation to be avoided during the mixing/homogenizing (0033) and results in a powder that can be easily fed into a mill or extruder (0034) for more effective fibrillation (0031).
Bankaitis also teaches that a fibrillation step, which is equivalent to the blending step (a2) of the claimed invention or the grinding step of modified Li (which causes the PTFE to fiberize/fibrillate), can be conducted at a temperature of at least 25°C, e.g., at least 30°C (0041). This would overlap the claimed range of 30°C or higher.
Although Bankaitis is directed towards an electrode rather than electrolyte film, the teachings regarding the temperature of PTFE would still be applicable to any application that uses PTFE as a binder. Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art. (see MPEP § 2143, F.).
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 modified the mixing/homogenization (a1) temperature of modified Li to be lower than 19°C as taught by Bankaitis in order to avoid fibrillation during the step and allow for more effective fibrillation later.
It would also have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the grinding/blending (a2) temperature of modified Li to be above 25°C as taught by Bankaitis as it is a known temperature for PTFE fibrillation and would result in nothing more than a grinding/blending step conducted at a temperature suitable for PTFE fibrillation. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. (see MPEP § 2143, B.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have routinely selected the overlapping portions of the disclosed grinding/blending/fibrillation temperature ranges as selection of overlapping portions of ranges has been held to be a prima facie case of obviousness (see MPEP 2144.05).
Bankaitis also teaches that the PTFE can be crystalline (0032), which displays a well-ordered, hexagonal crystal structure below about 19°C (0032) (step a1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the at least one TFE (co)polymer of modified Li to be crystalline PTFE as Bankaitis teaches it as a suitable form of PTFE for a binder and the simple substitution of one known element for another is likely to be obvious when predictable results are achieved (see MPEP 2143 B).
Additionally, it would be obvious to one of ordinary skill in the art that the Amorphous Index of the crystalline PTFE of modified Li would satisfy the claimed Amorphous Index (less than or equal to 0.22) as the Amorphous Index measures the degree of amorphousness of the material (higher value means more amorphousness) and crystalline PTFE would have low amorphousness (lower Amorphous Index value) as it is crystalline. Applicant is invited to provide evidence showing that the crystalline PTFE of modified Li would not have an Amorphous Index less than or equal to 0.22.
Regarding Claim 26, modified Li teaches the process of Claim 19. Li teaches that the binder can be one of polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer (ETFE) and polyperfluoroethylene propylene (PFEP) (0022). These would be considered as a TFE homopolymer or a blend between a TFE homopolymer and a TFE copolymer.
Regarding Claim 27, modified Li teaches the process of Claim 26. Li teaches that the binder can be polyperfluoroethylene propylene (PFEP/FEP), which is a copolymer of tetrafluoroethylene and hexafluoropropylene (AoKeray, pg. 1). PFEP can be considered a blend between a TFE homopolymer and a TFE copolymer.
Regarding Claim 28, modified Li teaches the process of Claim 19. Li teaches that the sulfide-based electrolyte has the formula [(100-x)Li2--S-xP2S5]-yM, where 0<x<50, 0≤y<2, and M is one or more of germanium sulfide, lithium phosphate, lithium oxide, germanium oxide, silicon oxide or aluminum oxide (0019). This formula would be considered as part of the Li2S-P2S5 system.
Claim(s) 22-23 and 29-30 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li, Lee, and Bankaitis as applied to claim 19 above, and further in view of Dandrea (US 20140127570 A1).
Regarding Claim 22, modified Li teaches the process of Claim 19. Modified Li teaches the blending/grinding step a2) but does not teach adding at least one lubricant.
Dandrea teaches that fibrillated PTFE binder particles will agglomerate with other fibrillated PTFE particles unless a lubricant is used (0004). The agglomeration reduces the effectiveness of PTFE as a binder (0004). Known lubricants include naptha (naphtha) (0004).
Although Dandrea is directed towards an electrode rather than an electrolyte film, the teachings regarding the behavior of unlubricated fibrillated PTFE binder particles would still be applicable to any application that uses PTFE as a binder. Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art. (see MPEP § 2143, F.).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have added a lubricant in the blending/grinding step in order to prevent agglomeration of fibrillated PTFE binder particles and any resulting decrease in binder effectiveness.
Regarding Claim 23, modified Li teaches the process of Claim 22. Modified Li does not teach a drying step to remove the lubricant.
Dandrea teaches that a drying step can be performed to prevent contamination as well as remove any lubricants/surfactants (Fig. 1; 0024).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of modified Li by adding a drying step as taught by Dandrea to prevent contamination as well as remove any lubricants/surfactants.
Regarding Claim 29, modified Li teaches the process of Claim 22. Modified Li does not teach that the lubricant is selected from the group consisting of isoparaffinic hydrocarbon compounds and petroleum fractions.
Dandrea teaches that naphtha is a known lubricant for PTFE (0004). Naphtha is a petroleum fraction.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the lubricant of modified Li to be naphtha as it is a known lubricant for PTFE.
Regarding Claim 30, modified Li teaches the proves of Claim 22. Modified Li does not disclose the amount of lubricant added.
Dandrea teaches that a mixture comprising a PTFE binder can contain 1-10 wt% of a processing aid (surfactant/lubricant). This would overlap the claimed amount of 5 to 35 parts by weight.
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, 191USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05
It would have been obvious to one of ordinary skill in the art before the effective filing date of to have modified the amount of lubricant added to be the amount taught by Dandrea as it is a known amount of lubricant for a mixture comprising a PTFE binder. It would also have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have routinely selected the overlapping portions of the disclosed ranges because selection of overlapping portions of ranges has been held to be a prima facie case of obviousness (see MPEP 2144.05 (I)).
Claim(s) 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li, Lee, and Bankaitis as applied to claim 19 above, and further in view of Visco (US 20160190640 A1).
Regarding Claim 24, modified Li teaches the process of Claim 19. Modified Li does not teach an additional calendaring step.
Visco teaches that a process for forming a sulfide (abstract) solid electrolyte sheet can comprise a second set of rollers (additional calendaring step) (0253; Fig. 6C). This allows the electrolyte sheet to be further shaped into the final product (0253; Fig. 6C).
Visco is considered analogous to the claimed invention as it relates to the same field of endeavor, namely sulfide solid electrolytes.
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 modified the process of modified Li to include a second pair of rollers (additional calendaring step) in order to further shape the electrolyte film.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Takahashi (US 20050008936 A1) teaches the use of PTFE as a binder in a cathode (0022). Conductivity decreases when the amount of PTFE exceeds 1 wt% (0139).
Burchardt `744 (US 20060257744 A1) teaches the use of PTFE as a binder in an electrode (0061). The PTFE can be added in an amount of less than 4 wt% to maintain high electronic conductivity of the electrode (0061).
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 ZIHENG LU whose telephone number is (703)756-1077. The examiner can normally be reached Monday-Friday 8:30 - 5 ET.
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, Nicholas Smith can be reached at (571) 272-8760. 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.
/ZIHENG LU/ Examiner, Art Unit 1752
/NICHOLAS A SMITH/ Supervisory Primary Examiner, Art Unit 1752