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 § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Independent claims 1 and 12 recite a plurality of porous graphene sheets comprising graphene oxide, reduced graphene oxide, graphite oxide, or a combination thereof. Initially, it is unclear how a “graphite oxide” can be considered a “graphene sheet.” The terms “graphite” and “graphene” are considered to be separate and distinct in the art and it is not clear how graphite can be a species of graphene as recited by the claim language. Further, the specification discloses the following in reference to Figure 8: “reduced graphene oxide (e.g., porous carbon sheet(s) (PCS).” The specification does not make it clear how a graphite oxide could be a porous carbon sheet (porous graphene sheet).
The claims further recite “wherein a portion of edges of a portion of the plurality of porous graphene sheets are oxidized and comprise an oxygen content of about 0.5% to about 10%”. It is unclear what portion(s) of the porous graphene sheets comprise the recited oxygen content. In one interpretation, which appears to be supported by the specification, the porous graphene sheets, as a whole, contain the recited oxygen content. In another interpretation, the “portion of edges” of the sheets contain the recited oxygen content. Correction is required.
Claims 13 and 14 recite that the oxygen content is less than about 5% (less than about 2%). This is indefinite as it fails to properly further limit the recitation in the parent claim of “about 0.5% to about 10%” because it extends beyond the scope of the parent 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.
Claims 1-8, 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over CN 104617300.
Regarding claim 1, the reference is directed to an energy storage device comprising an anode (negative electrode) that comprises a reduced graphene oxide product (abstract). Although the reference does not disclose that the reduced graphene oxide is a “porous graphene sheet,” it is submitted that the reduced graphene oxide of the reference would inherently be a porous sheet since it is made in a substantially identical manner to the claimed product. In particular, the product of the reference is made by oxidizing graphite (page 4, 6th paragraph of translation), exfoliating the graphite oxide to produce graphene oxide, and then chemically reducing the graphene oxide to produce a reduced graphene oxide (page 4, 4th and 5th paragraphs). The claimed product is made by chemically oxidizing graphite and exfoliating to produce graphene oxide, then chemically reducing the graphene oxide to form the porous carbon sheets (par. [0048] of publication of instant application). This is substantially identical to the method of CN ‘300. Further regarding claim 1, the anode further comprises a conductive additive and a binder (page 13, first paragraph). The battery of Example 5 (page 13) would inherently comprise a separator. The battey also comprises a positive electrode that appears to comprise a “lithium tablet” (Example 5). Regarding claims 2 and 3, the binder of the anode is PVDF and the additive is carbon black (page 13, first paragraph).
The reference does not expressly teach that “a portion of edges of a portion of the plurality of porous graphene sheets are oxidized” as recited in claim 1. It is further not taught that the porous graphene sheets (or a portion of the plurality of graphene sheets) comprise an oxygen content of about 0.5 to about 10%, as claim 1 is interpreted as reciting.
However, the limitation of “a portion of edges of a portion of the plurality of porous graphene sheets are oxidized” would be met by the reference as the processes of manufacture are identical as noted above. That is to say, the process of CN ‘300 would result in a portion of edges of a portion of the sheets being oxidized (at least some of the sheets would have a portion of the edges oxidized). Further, the reference teaches that the reduced graphene oxide comprises an amount of oxygen-containing functional groups that can be “adjusted and controlled” (page 8, 4th paragraph). Yet further, on page 3, it is disclosed that it is the aim of the invention is to “remove most of the oxygen-containing groups to improve its electrical conductivity, and retain a part of the oxygen-containing group to undergo redox reaction with lithium ion as an active site for deintercalating lithium ions.” It would have been obvious to use an amount of oxygen in the reduced graphene oxide that falls within the claimed range of about 0.5 to about 10% as claimed. It has been held that the discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art. In re Boesch, 205 USPQ 215 (CCPA 1980).
The reference further does not expressly teach that the positive electrode in Example 5 comprises an active material and a binder, as recited in claim 1 (the electrode is disclosed to be “Lithium tablets”).
However, the invention as a whole would have been obvious to one skilled in the art at the time of filing because a positive electrode with an active material and a binder is a structure that is conventionally used in a lithium ion battery. For example, a cathode comprising lithium cobalt oxide and a binder would be known to one skilled in the art. Therefore, claims 1 and 4 would be rendered obvious.
Regarding claims 6 and 7, a battery employing an electrode having the reduced graphene oxide would be expected to have a cycle life and equivalent series resistance within the claimed ranges. With respect to claim 5, the storage capacity (in mAh) is a parameter that represents the absolute size of the battery and can be scaled up or down according to the needs of the artisan.
Regarding claim 8, the separator permeability (Gurley value) is a parameter that can be optimized to affect porosity and subsequently ion mobility/conductivity when the separator is infused with electrolyte. It has been held that the discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art. In re Boesch, 205 USPQ 215 (CCPA 1980).
Regarding claim 10, this claim recites that the porous graphene sheets comprise about 2 to about 10 sheets. On page 8 of CN ‘300, it is disclosed that a multi-pleated sheet like structure of the graphene oxide can be observed. It would have been obvious to have the porous graphene sheets (or an arbitrary portion thereof) comprise 2 to 10 sheets as claimed.
Regarding claim 11, the pore size of the porous graphene sheets could be expected to be in the range of 1-10 nm, based on the process of CN ‘300 being identical to the process disclosed in the instant specification. Further it is disclosed on page 8 that the product “exhibits many nanometer to micrometer-scale pores.” Accordingly, the limitation is rendered obvious.
Claims 12-20 are rejected under 35 U.S.C. 103 as being unpatentable over Lim et al (US 20140370383) in view of CN 1004617300.
Regarding claim 12, Lim et al. is directed to an electrode (either an anode or a cathode) for a lithium ion battery ([0090], [0091]), which is made by a process of: combining a binder and a solvent ([0079]), heating the binder and solvent ([0079]), mixing an active material into the binder mixture to form a slurry ([0088]), roll coating the slurry onto a foil ([0097]), drying the slurry ([0097], [0104]), calendering (roll pressing) the slurry on the foil ([0104]) and slitting (punching) to form the electrode ([0105]). Regarding claim 15, the binder can be PVDF, among others ([0080], [0084]). Regarding claim 16, the active material (in the case of a cathode) may comprise a lithiated metal compound such as LiNiCoAl oxide, LiNiMnCo oxide, or LiMnPO4 ([0090]). Regarding claim 12, in the case of an anode the active material may be a carbon material ([0091]). Both electrodes may comprise a carbonaceous conductive material such as carbon black ([0092], Table 1).
Lim et al. do not expressly teach that the active material comprises porous graphene sheets as recited in claim 12, or that the active material is a combination of porous graphene sheets and lithiated metal compound (claim 16). It is also not taught that “a portion of edges of a portion of the plurality of porous graphene sheets are oxidized” as recited in claim 12. It is further not taught that the porous graphene sheets (or a portion of the plurality of graphene sheets) comprise an oxygen content of about 0.5 to about 10%, as claim 12 is interpreted as reciting.
CN ‘300 is directed to an energy storage device comprising a cathode or an anode that comprises a reduced graphene oxide product (abstract). Although the reference does not disclose that the reduced graphene oxide is a “porous graphene sheet,” it is submitted that the reduced graphene oxide would inherently be a porous sheet for the reasons set forth in the rejection above.
Therefore, the invention as a whole would have been obvious to one skilled in the art at the time of filing because the artisan would be motivated to use the porous graphene sheets of CN ‘300 as the active material and/or conductive material of the anode or cathode of Lim et al. In the abstract, CN ‘300 teaches that when used as an anode material, “the relatively high specific discharge capacity can be achieved, up to 280 mAh/g, and good circulation stability and excellent rate performance are achieved” (abstract). Further, when used as a cathode material, “the specific discharge capacity can be kept being 900 mAh/g and more than 900 mAh/g after 100 rounds of charge discharge circulation can the circulation stability is relatively good” (abstract). Therefore, the artisan would be motivated to use the porous graphene sheets of CN ‘300 as the active material and/or conductive material of the anode or cathode of Lim et al.
Further, the limitation of “a portion of edges of a portion of the plurality of porous graphene sheets are oxidized” in claim 12 would be met by the CN ‘300 as the processes of manufacture are identical as noted above. Further, it would have been obvious to use an amount of oxygen in the reduced graphene oxide that falls within the claimed range of about 0.5 to about 10% (less than 5%, less than 2%) as claimed. The discussion of the CN ‘300 reference in the rejection above as it relates to oxygen-containing functional groups is incorporated herein. Claims 12-14 are therefore rendered obvious.
Regarding claim 16, which recites that the active material is a combination of porous graphene sheets and lithiated metal compound, it would be obvious to either (a) replace only a portion of the lithiated metal compound of Lim et al so as to result in the combination, or (b) use the porous graphene sheets as the conductive carbon material combined with the lithiated metal compound active material. Note: the label “active material” is considered to be functional in nature and not structural, that is, a material present in the electrode may have functionality as an active material but not be disclosed as such. Such a designation also depends on the specific counterelectrode material and the emf between the relevant material pair(s).
Regarding claim 18, a plurality of the porous graphene sheets of CN ‘300 would have a pore diameter of 1-10 nm as claimed (note rejection above). Regarding claim 17, the sheets would inherently have a single layer of graphene (graphene is one layer by definition).
Regarding claim 19, it would be obvious to apply a metal tab to the finished electrode as this is a conventional step of construction in prismatic or wound lithium ion batteries. Accordingly, claim 19 would also be rendered obvious.
Allowable Subject Matter
Claim 9 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Claim 9 recites that carboxylic acid functional groups are bonded only to one or both of a top sheet or a bottom sheet of the porous graphene sheets. CN ‘300, the closest prior art, teaches that the reduced graphene oxide contains various functional groups including carboxyl groups (page 5) but does not teach or fairly suggest the claimed subject matter.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Jonathan Crepeau whose telephone number is (571) 272-1299. The examiner can normally be reached Monday-Friday from 9:30 AM - 6:00 PM EST.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Basia Ridley, can be reached at (571) 272-1453. The phone number for the organization where this application or proceeding is assigned is (571) 272-1700. Documents may be faxed to the central fax server at (571) 273-8300.
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/Jonathan Crepeau/
Primary Examiner, Art Unit 1725
March 7, 2026