DETAILED ACTION
Application 16/120875, “METHOD OF EXTENDING CYCLE-LIFE OF A LITHIUM METAL SECONDARY BATTERY”, was filed on 9/4/18, and is a CIP of application 16/014623 filed on 6/21/18.
This Office Action on the merits is in response to claims and amendments filed 6/16/26.
First Inventor to File Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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.
Response to Arguments
Applicant's arguments filed on 6/16/26 have been fully considered but are moot in view of the new ground(s) of rejection necessitated by amendment.
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 of this title, 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.
Claims 1-2, 4-7, 11-14 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Lee’185 (US 2019/0058185), Zhamu’656 (USP 9564656), Viner (US 2019/0088958), Rao (USP 4322317) and Wietelmann (USP 6506516).
Regarding claims 1-2, 4-7, 11-14 and 20, Lee’185 teaches a method comprising implementing two anode-protecting layers (item 120, 130) between an anode active material layer (item 110) and a porous separator/electrolyte (Figures 1 and 2; paragraph [0089]), wherein said two anode-protecting layers comprise:
a) a first anode-protecting layer (item 130) having a thickness from 1 nm to 100 micrometers (paragraph [0054]) and comprising a thin layer of electron-conducting material selected from graphene sheets, carbon nanotubes, carbon nanofibers, carbon or graphite fibers, expanded graphite flakes, metal nanowires, conductive polymer fibers, or a combination thereof (paragraph [0041, 0022, 0069]); and
b) a second anode-protecting layer (item 120) in physical contact with said first anode-protecting layer (see Figure 2), having a thickness from 1 nm to 100 micrometers (paragraph [0052]) and comprising a composite including an ionically conductive polymer and electron-conducting material [carbon nanotube] (paragraph [0041]),
c) wherein said ionically conductive polymer of the second anode-protecting layer comprises a lithium ion-conducting additive dispersed therein (paragraph [0062-0064] where the “lithium salt” is the lithium-ion conducting additive).
The requirement that the method is a method of improving cycle-life on a lithium metal secondary battery contained in the preamble is found to be a non-limiting statement of intended purpose. For completeness of record, it is noted that Lee’185 teaches the same or a similar lithium metal secondary battery life cycle improvement (paragraph [0013]).
Lee’185 teaches the first anode protecting layer being a membrane formed of carbon nanotubes and conductive polymer (paragraph [0048]), but does not expressly teach the first anode layer is comprised of fibrous material, such as carbon nanofibers, such that the layer is in a form of a paper sheet, membrane, foam, fabric, non-woven or aggregate of conductive material and has a specific surface area of 50 m2/g or greater.
In the battery art, Zhamu’656 teaches that a conductive layer for supporting an anode active material is desirably formed from a fibrous material agglomerate configured to have ultra-high specific surface area for the benefit of inhibiting dendrite formation and enabling high re-charge rates (c24:53-c25:28). Zhamu further teaches that the fibrous material may include such as carbon nanotube and/or carbon nanofiber (c25:2-4). Zhamu’656 suggests specific surface area of at least 500 m2/g as exemplary high specific surface area values (c8:7-15).
It would have been obvious to a person having ordinary skill in the art at the time of invention to provide the first anode-protecting layer in a form comprised of fibrous material, such as carbon caron nanotubes and/or nanofibers, such that the layer is in a form of a paper sheet, membrane, foam, fabric, non-woven or aggregate of conductive material and having a specific surface area of 50 m2/g or greater for the benefit of providing a of inhibiting dendrite formation and enabling high re-charge rates for a battery as taught by Zhamu’656.
Lee’185 further teaches that the layer 120 has ionic conductivity (paragraph [0051]), but does not expressly teach the layer having a lithium ion conductivity from 10-8 S/cm to 5 x 10-2 S/cm when measured at room temperature.
However, the claimed conductivity ranges represent, or substantially overlap with, the ranges conventionally understood to embody good ionic conductivity, respectively. For example, in the battery art, Viner teaches a protective layer having ionic conductivity ranges substantially overlapping that claimed (see paragraphs [0033, 0054]).
It would have been obvious to a person having ordinary skill in the art at the time of invention to configure second anode-protecting layer conductive layer to have conductivity values lying within the claimed range for the benefit of ensuring adequate ionic conductivity as was known in the art at the time of invention.
Lee’185 does not expressly teach that the ionically conductive polymeric material comprises an elastomer having a fully recoverable tensile elastic strain, as claimed. Additionally, Lee does not appear to teach wherein the ion conductive polymer is an ethylene propylene diene rubber [EPDM], which is an elastomer mentioned as having desirable elasticity in applicant’s specification.
Although Lee does not teach an ethylene propylene diene rubber [EPDM] as the ion conducting polymer, Lee does further teach sulfonated or non-sulfonated ethylene propylene diene polymer as a binder material for the positive electrode (paragraph [0085]).
Additionally, in the battery art, Rao teaches that EPDM rubber is well known and desirable as an ionomer [ion conducting elastomer] with binding property (c4:1-30).
It would have been obvious to a person having ordinary skill in the art at the time of invention to utilize EPDM as the ion conductive polymer for the protective layer of Lee for the benefit of providing a polymer known to have both desirable ion conductivity and binding properties in view of the cited art.
As to the 6/16/26 amendment, Lee teaches the second anode-protecting layer comprises a lithium ion-conducting additive dispersed therein (“lithium salt” of paragraph [0062-0064]), and further teaches that “any material used as a lithium salt in a battery field may be used as the lithium salt, and typical examples thereof may include… LiPF6…”, but does not teach the lithium salt being one of the presently claimed species such as lithium bis(oxalate) borate [LiBOB].
However, each of Zhamu’656 (c22:32-38) and Viner (paragraph [0134]) teach lithium bis(oxalate)borate as a suitable alternative lithium salt to LiPF6.
Moreover, in the battery art, Wietelmann teaches lithium bis(oxalate)borate as an alternative lithium conducting salt to more conventional LiPF6, and that lithium bis(oxolato)borate specifically has advantages over other salts in terms of desirable thermal stability, handling, manufacturability, high voltage stability, ion conductivity safety and/or economy (c1:5-c2:49).
Thus, it would have been obvious to a person having ordinary skill in the art at the time of invention to utilize lithium bis(oxalate)borate in place of the lithium salt of Lee’185 as a matter of simple substitution of one known lithium salt for another to yield predictable results. Additionally, a teaching-suggestion-motivation rationale for replacing LiPF6 with LiBOB exists as Wietelmann teaches lithium bis(oxalate)borate as an inventive salt with advantages in terms of desirable thermal stability, handling, manufacturability, high voltage stability, ion conductivity safety and economy, useful for replacing more conventional salts such as LiPF6.
The materials recited in claims 2, 11-14 and 20 are the same or substantially the same as those cited in the prior art and thus do not distinguish the claimed invention from the prior art. (Lee’185 [0089] liquid electrolyte; Lee’185 [0015] carbon nanotube; Lee’185 [0083] lithium cobalt oxide; Rao for elastomer).
The deposition/stacking sequence described in claims 4-6 is found to be a matter of obvious design choice considering that the selection of any order of performing processing steps is prima facie obvious, absent new or unexpected results associated with the steps (MPEP 2144.04 IVC). In this case, the product produced is substantially the same regardless of order of manufacture, thus the selection of any order is prima facie obvious.
Regarding claims 7, the prior art further suggests that the ionomer may include 0.1 to 50% of the ion conductivity enhancing species recited in claim 10 at Lee’185 paragraph [0020] and/or Rao, considering that the disclosed species may be utilized in combination. Alternatively, the claimed limitations are suggested by the nonpreferred embodiment disclosed by Lee’185 as Comparative Example 7.
Claims 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Lee’185 (US 2019/0058185), Zhamu’656 (USP 9564656), Viner (US 2019/0088958), Rao (USP 4322317) and Weitelmann (USP 6506516) and further in view of Yushin (US 2015/0064568).
Regarding claim 7, Lee’185 does not expressly teach that the ionically conductive material contains 0.1 to 50% of the inorganic ion conductive additives recited in claim 1.
In the battery art, Yushin teaches that the ion conductivity of battery components may be increased by including in the components inorganic additives, such as those claimed, which have donor metal ions for increasing ion conductivity (paragraphs [0008-0010, 0034]). Yushin further teaches that the amount of additive can be determined based on the amount of lithium needed to provide a desired capacity (paragraph [0010, 0012]) making the concentration added a result-effective variable obvious to optimize in accordance with MPEP 2144.05.
Thus, the modification of Lee’185 to include an inorganic ion conduction improving additive at the claimed concentration range is found to be prima facie obvious in view of Yushin.
Claims 15-21 is/are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Lee’185 (US 2019/0058185), Zhamu’656 (USP 9564656), Viner (US 2019/0088958), Rao (USP 4322317) and Weitelmann (USP 6506516) and further in view of Takeyama (US 2011/0143211).
Regarding claim 15-21, Lee’185 does not expressly teach that the inorganic material of the cathode active material may be a species selected from each of the listed Markush groups.
However, each of the listed Markush groups represent known types of inorganic material useful as cathode active material for lithium battery applications. For example, in the energy storage device art, Takeyama at paragraphs [0230-0234] teaches species among the listed as conventional cathode electrode active material alternatives.
The substitution of species among those claimed in claims 15-21 for those expressly disclosed by Lee’185 merely requires the simple substitution of one known cathode active material for another to yield predictable results; therefore, a prima facie case of obviousness exists in accordance with MPEP 2141.
Conclusion
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 JEREMIAH R SMITH whose telephone number is (571)270-7005. The examiner can normally be reached on Mon-Fri: 9 AM-5 PM (EST).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Milton Cano can be reached on 313-446-4937. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JEREMIAH R SMITH/Primary Examiner, Art Unit 1723
