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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement filed January 17, 2024 has been placed in the application file and the information referred to therein has been considered as to the merits.
With respect to foreign language references and foreign language patent office communications with no translation of the document: “If no translation is submitted, the examiner will consider the information in view of the concise explanation and insofar as it is understood on its face, e.g., drawings, chemical formulas, English language abstracts, in the same manner that non-English language information in Office search files is considered by examiner in conducting searches.” See MPEP §609.04(a)(II) (D) and 37 CFR 1.98(a)(3)(ii).
Drawings
The drawings received January 17, 2024 are acceptable for examination purposes.
Specification
The specification received January 17, 2024 has been reviewed for examination purposes.
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, 2 and 6-10 are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al. (U.S. Patent Application Publication No. 2020/0161635) in view of Takeshita et al. (JP2021-077592A).
As to claim 1, Liu discloses a negative electrode active material comprising:
a porous silicon particle 30; and
a carbon material 18,
wherein the porous silicon particle has a plurality of pores 16,
the carbon material 18 cover at least a part of an inner surface of each of the pores 16 (see Fig. 2 below, for example).
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296
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As to claims 6 and 7, Liu teaches that the carbon material 18 has the shape of a thin film that covers at least a part of an inner surface of each of the pores 16 (Fig. 2 above and para. [0017]) with the coating thickness being between 2-5nm (para. [0017]).
As to claim 10, Liu discloses the active material particles above in the construct of a battery, the battery 200 (paras. [0059]-[0062], Fig. 16) comprising:
an anode 202 (negative electrode);
a cathode 208 (positive electrode);
an electrolyte layer 214 disposed between the electrodes; wherein
the anode (negative electrode) includes the carbon-coated porous silicon active material according.
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Liu does not teach of the negative electrode active material including a solid electrolyte, the solid electrolyte covering at least part of an inner surface of the pores and the solid electrolyte in contact with the carbon material in the pores (claim 1); the particular volume ratio of solid electrolyte to silicon (claim 2); of the solid electrolyte being the shape of a thin film (claim 8) of 30nm or less (claim 9) or the battery including the active material according to claim 1 (claim 10).
As to claims 1-2 and 8-10 and the solid electrolyte covering at least part of an inner surface of the pores and the solid electrolyte in contact with the carbon material in the pores, Liu teaches that the electrolyte of the battery can be any conventionally recognized electrolyte including solid electrolyte systems (para. [0062]).
Takeshita is drawn to the same field of endeavor, porous active materials for battery applications. Takeshita teaches that the inclusion of solid electrolyte 102 into the pores 101 of the active material 100 can be applied to any number of conventionally recognized active materials including porous silicon based materials (para. [0074]). The inclusion of electrolyte within the pores of the active material was shown by Takeshita to improve electrochemical performance such as improved cycling, suppressed volumetric expansion, energy density and improve safety of the battery (Figs. 1 and 2, claims 1-2 and 8-10).
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Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the carbon-coated porous silicon particles of Liu to further include a solid electrolyte layer within the pores and thus in contact with the carbon coating within the pores as the inclusion of the solid electrolyte to the porous silicon active material would have predictably and expectedly achieved benefits of such inclusion as taught by Takeshita including, but not limited to, improved electrochemical performance such improved cycling, suppressed volumetric expansion, energy density and improve safety of the battery.
As to the solid electrolyte having a shape of a thin film with an average thickness of 30nm or less (claims 8-9):
As the pores of Liu are on the order of 2-5nm, upon providing the solid electrolyte of Takashita to the active material pores of Liu, the thickness of the solid electrolyte will be on the order of 2-5nm in order to effectively form in the pores, thus constituting a thin film having a shape of a thin film (i.e., formed thinly) covering at least a part of an inner surface of each of the pores and with an average thickness of 30nm or less (claims 8 and 9). Generally, differences in ranges will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such ranges is critical. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969).
As to claim 2, modified Liu does not explicitly teach of the volume ratio of solid electrolyte to silicon in a range from 0.5% to 15%.
Takeshita teaches that the solid electrolyte in the active material ranges from 10-60% (para. [0059]) to provide sufficient ion conductivity within the porous active material. Takeshita further teaches of the pore content from 15-80%, preferably 35-60% with the pores having at least 10% solid electrolyte therein.
As to meeting a ratio of volume of solid electrolyte to Si in the range from 0.5-15% of claim 2, it would have been of routine optimization in the art to vary the amount of solid electrolyte within this range while still achieving good ion conductivity within the silicon pores.
Electrolyte or ion conducting coatings applied to and within active materials are commonly adopted to improve ionic conductivity. Takeshita itself teaches that the solid electrolyte in the active material ranges from 10-60% in the pores of silicon based active material (paras. [0059] and [0074]). Takeshita further teaches of a broad pore volume and a broad mass ratio of solid electrolyte to active material. The mass ratio of porous active material to inorganic solid electrolyte (porous active material / inorganic solid electrolyte) or the mass ratio of porous active material to organic polymer solid electrolyte (porous active material / organic polymer solid electrolyte) is 5 / It is preferably 95 or more and 95/5 or less (para. [0055]). The pore volume is preferably, but not Iimited to 10% or more of all pores (paras. [0053]-[0059]). Inclusion of a solid electrolyte to the pores of Liu would have been obvious in light of the further teachings of Takashita for reasons previously discussed and the optimization of the amounts of carbon, solid electrolyte, active material and porosity would have been routine tuning to effectively optimize and tune an active material to have good mechanical properties, electron conductivity, ion conductivity and electrochemical performance.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of modified Liu to have the amount of solid electrolyte present in a minor amount (lower weight and lower volume percent) as further taught by Takeshita and since it would have provided for an active material having sufficiently good ion conductivity within the porous active material itself while effectively tuning the active material including carbon and solid electrolyte therein to have good mechanical properties, electron conductivity, ion conductivity and electrochemical performance. It is also noted that differences in ranges will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such ranges is critical. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969).
Furthermore, restricting the solid electrolyte amount to a particular lower range appears to be nothing more than routine optimization of a known parameter. Takeshita already teaches of porous nanostructured silicon particle with internal pores provided with an amount of solid electrolyte therein which only partially occupies the pores. Given the teachings above a person of ordinary skill in the art would have had ample knowledge and motivation with predictable success to adjust the solid electrolyte loading within known effective ranges thereby arriving at and including lower volume fractions as a straightforward and routine optimization rather than as a result of an inventive step.
Generally, differences in ranges will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such ranges is critical. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Liu et al. (U.S. Patent Application Publication No. 2020/0161635) in view of Takeshita et al. (JP2021-077592A) as applied to claim 1 above, and further in view of Park et al. (U.S. Patent Application Publication No. 2017/0133665).
Modified Liu does not teach of the volume ratio of carbon to silicon in a range from 0.01% to 20%.
Liu teaches of a porous silicon particle having 50-60% porosity prior to carbon coating and 20-30% porosity after carbon coating. Liu further teaches that the pore volume prior to coating is about 0.6-0.7 cm3/g (para. [0040]). Liu further teaches that the weight % of carbon ranges from 10-45% (para. [0045]). The porosity before coating ranges from 50-60vol% (50-40 vol% Si) and then 20-30vol% after carbon coating (para. [0040]) which would suggest about 20-30vol% pores, 40-50 vol% Si, 20-40% C. The inclusion of carbon is shown to improve stability of the porous silicon while improving electron conductivity.
As to meeting a ratio of volume of C to Si in the range from 0.01-20% of claim 3, it would have been of routine optimization in the art to vary the amount of carbon within this range while still achieving good stability and electron conductivity of the carbon coating.
Carbon coating is commonly adopted to improve electrical conductivity and mitigate volume expansion during the modification of silicon- based active material. Park, being drawn to the same field of endeavor silicon active material with carbon coatings recognized that the amount of carbon can be lowered to 10-25wt% to achieve sufficient electron conductivity and material stability. Park thus further shows that silicon to carbon tuning was understood for obtaining an active material with good mechanical and electrochemical performance characteristics was well known in the art.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of modified Liu to have the amount of carbon present in a lower weight and lower volume percent, including volume percents in the range from 0.5-20%, as further taught by Park since it would have predictably provided for an active material having sufficiently good mechanical and electrochemical performance characteristics. In addition, differences in ranges will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such ranges is critical. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969).
Restricting the carbon amount to a particular lower range appears to be nothing more than routine optimization of a known parameter. Liu already teaches of porous nanostructured silicon particle with internal pores provided with an amount of carbon therein which only partially occupies the pores. Given the teachings above a person of ordinary skill in the art would have had ample knowledge and motivation with predictable success in adjusting the carbon loading within known effective ranges thereby arriving at and including lower volume fractions as a straightforward and routine optimization rather than as a result of an inventive step.
Claims 4-5 are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al. (U.S. Patent Application Publication No. 2020/0161635) in view of Takeshita et al. (JP2021-077592A) as applied to claim 1 above, and further in view of Yang et al. (U.S. Patent Application Publication No. 2014/0147751).
Modified Liu does not teach of the carbon material including nanoparticles (claim 4) having an average diameter of 50nm or less (claim 5).
As discussed above, Liu teaches that the carbon material 18 has the shape of a thin film that covers at least a part of an inner surface of each of the pores 16 (Fig. 2 above and para. [0017]) with the coating thickness being between 2-5nm (para. [0017]).
While Liu obtains the coating via vapor deposition, it was well known in the art to apply coatings via vapor deposition, liquid deposition or by dispersing a solid carbon source in solvent (Yang, paras. [0014]-[0021]). Yang is drawn to the same field of endeavor, silicon-carbon anode materials for lithium batteries. Again, Yang teaches that providing a carbon material can be achieved by providing a solid carbon material in a solvent as much as it can be achieved via vapor or liquid deposition (claim 4). In keeping with Liu, the relative size of the carbon particles would expectedly be retained in the dimension sought by the carbon coating of Liu, 2-5nm (para. [0017], to claim 5).
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of Liu to form the carbon coating by any number of conventional suitable means including providing a solid carbon material in a solvent as taught by Yang since it would have predictably provided for suitable carbon deposition within the porous silicon particle.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. U.S. Patent Application Publication No. 2009/0029256 discloses a porous silicon particle with carbon inside some of the pores.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GREGG CANTELMO whose telephone number is (571)272-1283. The examiner can normally be reached Mon-Thurs 7am to 5pm.
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/GREGG CANTELMO/Primary Examiner, Art Unit 1725
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