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 .
Status of Claims
Applicant’s amendment and arguments, filed 06/18/26, have been fully considered. Claim(s) 9 and 13 is/are amended; claim(s) 27 and 28 stand(s) as originally or previously presented; claim(s) 1–4, 6, 8, 17, 18, and 22–26 remain(s) withdrawn; claim(s) 5, 7, 10–12, 15, 16, and 19–21 is/are canceled; and claim 29 is added without entering new matter. Examiner affirms that the original disclosure provides adequate support for the amendment.
Upon considering said amendment and arguments, the previous claim objections set forth in the Office Action mailed 03/18/26 have been withdrawn, but the pending 35 U.S.C. 103 rejection has been maintained and altered as necessitated by amendment.
Claim Objections
Claims 9 and 29 are objected to for the following informalities: in lines 24 and 1, respectively, “the conductive material” is suggested to read “the electrode conductive material” for consistent claim terminology based on claim 9’s prior recitation. Appropriate correction is required.
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 9, 13, 14, and 27–29 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.
A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, claim 9 recites the broad recitation “the electrode conductive material comprises carbon nanotubes (CNT)” (line 8), and the claim also recites “wherein the conductive material consists essentially of the CNT” (line 24), which is the narrower statement of the range/limitation. The claim(s) are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims.
As Applicant has amended claim 9 so that “the conductive material consists essentially of the CNT”, for this Office Action claim 9 will be interpreted to require that “the conductive material consists essentially of the CNT” rather than the broader “comprises”.
The dependent claims fail to correct this deficiency and are rejected likewise. Appropriate correction is required.
Claim Interpretation
Claim 9’s “dry electrode” (line 1) will be interpreted as one using no solvent during manufacturing, as specially defined on p. 9, line 12.
Claim 9 further recites “wherein the electrode active material layer includes a free-standing type film” (line 3). For this Office Action the “free-standing type film” will be interpreted as “an object which can maintain its own shape without relying on other members and can be transferred or handled by itself,” as specially defined on pp. 16 and 17.
Claim Rejections - 35 USC § 103
The text forming the basis for the rejection under 35 U.S.C. 103 may be found in a prior Office Action.
Claim(s) 9, 13, 14, and 27–29 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mashtalir et al. (WO 2023183754 A1) (Mashtalir) in view of Nagai et al. (WO 2022270361 A1, with EFD 06/25/21; citation to English equivalent US 20240290971 A1) (Nagai).
Regarding claims 9, 13, 14, 27, and 28, Mashtalir discloses an electrochemical device (battery, e.g., ¶ 00200) comprising a positive electrode, a negative electrode and a separator layer interposed between the positive electrode and the negative electrode (e.g., ¶ 00201–0204), wherein at least the positive electrode is a dry electrode (e.g., ¶ 0065 and Ex. 5 (produced without solvent), ¶ 00252–00256 and Table E with exs. such as E2) comprising a current collector (e.g., ¶ 00255); and an electrode active material layer formed on at least one surface of the current collector (e.g., ¶ 00253–00255), wherein the electrode active material layer includes a free-standing type film (e.g., ¶ 00254);
wherein the electrode active material layer comprises an electrode active material, an electrode conductive material and an electrode binder (NCM622, carbon black (CB) additive, and fibrillated PTFE, respectively, e.g., ¶ 00253 and Table E, Ex. E2), wherein the electrode binder has a fibrilized structure which binds the electrode active material and the electrode conductive material (e.g., ¶ 0036, 00253).
Mashtalir further discloses, as noted above, a high-surface-area carbon black electrode conductive material, i.e., a dot-like conductive material (instant spec., p. 4, line 20), yet, while further disclosing that the carbon black is usable alongside other conductive carbon additives (e.g., ¶ 0157–0159), fails to explicitly disclose that the electrode conductive material consists essentially of carbon nanotubes (CNT) having a BET specific surface area of 80 m2/g.
Nagai, in teaching a battery positive electrode composition (Title), teaches that the conductive material is carbon black and carbon nanotubes (CNTs) (Abstract), where the carbon black exhibits similarly high surface area of 100–400 m2/g (¶ 0016). Nagai teaches that this composition allows the conductive material to be uniformly dispersed, efficiently form a conductive path, and maintain excellent battery characteristics even when the conductive material’s content is reduced (¶ 0019). Nagai further teaches that the CNTs exhibit a BET specific surface area of 170–320 m2/g because this range allows more electrical contact points with the active and conducting materials to form while uniformly dispersing the CNTs (¶ 0054), further teaching preferably 180–300 m2/g to reduce internal resistance and achieve higher discharge-rate and cycle characteristics (¶ 0055).
Nagai and Mashtalir are analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely conductive material in battery electrodes.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use a mixture of CNTs and carbon black as Mashtalir’s conductive material, as taught by Nagai, with the reasonable expectation of allowing the conductive material to be uniformly dispersed, efficiently form a conductive path, and maintain excellent battery characteristics even when the conductive material’s content is reduced, as taught by Nagai. It would have been further obvious to configure the CNTs to exhibit a BET specific surface area of 180–300 m2/g—falling within 80 m2/g or more (claim 9) and 80–800 m2/g (claim 13)—with the reasonable expectation of increasing electrical contact points between the active and conductive materials, uniformly dispersing the CNTs, reducing internal resistance, and achieving higher discharge-rate and cycle characteristics, as taught by Nagai.
Examiner notes that “consists essentially of” requires the claims or specification to clearly indicate the basic and novel characteristics of the relevant component to determine whether any coincident component(s) would fundamentally alter such characteristics, or, else, “consists essentially of” is to be treated as “comprising” under 103 (see MPEP 2111.03 (III); note also that both Mashtalir and Nagai allow as little as 0.1 wt% CB in the electrode (see ¶ 0148 of Mashtalir, ¶ 0031 of Nagai)). As the specification and claims appear devoid of such an indication, the limitation “the electrode conductive material consists essentially of the CNT” appears open to other conductive material alongside the CNT. Thus, modified Mashtalir’s CB/CNT mixture reasonably satisfies the aforementioned limitation.
Additionally or alternatively, claim 9’s preamble employs the open-ended term “comprising”, meaning the claim is open to the electrode conductive material as, e.g., a first conductive material alongside any number of other conductive materials as, e.g., second or third conductive materials. Thus, modified Mashtalir’s CNT could be considered the (first) electrode conductive material—such that “the electrode conductive material consists essentially of the CNT”—while modified Mashtalir’s CB could be considered a second electrode conductive material and still satisfy the limitation.
In either case, such also further satisfies claim 14’s “the electrode conductive material further comprises a dot-like conductive material” (per instant spec. at p. 4, line 20, CB is a dot-like conductor, which is further supported by granulated CB in Mashtalir, e.g., ¶ 0125; see also Ketjenblack EC-600J, i.e., granulated/dot-like CB, in Mashtalir’s exs. in ¶ 0219).
Mashtalir further discloses, as noted above, a PTFE binder (e.g., ¶ 0085 and electrode C4, Table C), as well as the ability to include an additional, non-fibrillizable binder such as PVDF (¶ 0088, 0089, 0091), disclosing that this additional binder can serve as a glue to connect the active material together and provide adhesion to the current collector (¶ 0088; see also separate embodiments partially substituting PTFE with PVDF in ¶ 0260), though Mashtalir fails to explicitly disclose, within Ex. 4, using each binder.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to incorporate PVDF alongside Mashtalir’s PTFE binder with the reasonable expectation of connecting the active material together and providing adhesion to the current collector, as suggested by Mashtalir.
Regarding the crystallinity values of 0% for PVDF and greater than 0% to 15% for PTFE, Mashtalir further discloses that the binder polymer may initially be semi-crystalline (¶ 0027) but discloses that the binder (such as PTFE in Ex. E2 above) is pre-blended with conductive and active materials and then extruded via twin screw at 100°C and 400 rpm to disperse the carbon and fibrillate the binder (¶ 00253; note that the “non-fibrillizable binder” such as PVDF may undergo the same processing even if it does not fully fibrillate, as seen in Mashtalir’s ¶ 0087 and 0089). Importantly, the spec.’s p. 25, lines 15–24, explains that forming the binder-containing extrudate via twin-screw extruder at, e.g., 100–300°C and 50–600 rpm allows each of the PVDF-based and PTFE binders to achieve ≤ 30% crystallinity—and, ultimately, the recited 0% and greater than 0% to 15%, respectively (see examples).
As Mashtalir discloses a substantially similar twin-screw extrusion of PTFE (alongside the ability to extrude PVDF) at substantially similar conditions as the instant specification, the skilled artisan would have reasonably expected each of Mashtalir’s PVDF and PTFE’s crystallinity values to fall within or at least overlap 0% and greater than 0% to 15% (claim 9) or 0% and greater than 0% to 10% (claim 28), respectively, absent evidence otherwise (MPEP 2112.01 (I)), such that the skilled artisan could have routinely selected within each respective overlap with a reasonable expectation of forming a successful binder with suitable crystallinity and physical properties (MPEP 2144.05 (I)).
Alternatively, based on this rationale, the skilled artisan would have expected Mashtalir’s process to produce crystallization values close to the respectively recited values (MPEP 2112.01 (I)), and the skilled artisan would have expected substantially similar performance from the prior-art values absent demonstrated criticality to each of the recited values (MPEP 2144.05 (I). Specifically, the spec.’s p. 15, lines 2–17, appears to indicate no criticality by generally disclosing that each binder’s crystallinity may be ≤ 30% (see also p. 16, lines 8–14, where each crystallinity value may be as low as 0%), and Mashtalir never attributes inferior performance to crystallinity values outside the range. Thus, absent demonstrated criticality, each crystallization range appears obvious over Mashtalir.
Regarding the electrode conductive material’s being 0.1–0.8 wt% based on a total weight of the electrode active material layer, Mashtalir further exemplifies, in example E2 above, 1% carbon black conductive material (Table E) but more broadly allows preferably 0.3~3 wt% (¶ 00148). Similarly, for further reducing internal resistance and improving discharge rate and cycling, Nagai teaches a content of 0.01–5 mass% carbon black in the electrode and 0.01–3 mass% CNTs in the electrode (¶ 0031 and 0058, respectively). More broadly, the skilled artisan would recognize that each of Mashtalir’s carbon black and Nagai’s CNTs—the components constituting the conductive material—must necessarily be included at weights sufficient to perform their respective functions (conductivity and mechanical strength for carbon black (Mashtalir’s ¶ 0093) and increasing electrical contact points between active and conductive materials for CNTs (Nagai’s ¶ 0054)) without detracting from the active material’s necessary effect of providing capacity through ion (de)intercalation and the binder’s effects of affording mechanical stability and holding the active material together, as well as providing adhesion to the collector (Mashtalir, e.g., ¶ 0062 and 0036/0088, respectively).
To balance all these effects, it would have been obvious to arrive at the recited (total) weight percentage of conductive material by routinely optimizing the carbon black and CNTs’ weight ratios in the active layer (MPEP 2144.05 (II)).
Mashtalir further discloses that a content of the electrode active material is, e.g., 97 wt% based on a total weight of the electrode active material layer (Ex. E2, Table E), falling within ≥ 97%.
Mashtalir further discloses that the dry electrode has an in-plane electrode resistivity of, e.g., 15~20 ohm-cm (electrode C4 (manufactured without solvent and using fibrillated binder, ¶ 00245–00248), FIG. 6; see also ¶ 0051 for in-plane) and, while further disclosing that electrode performance can be tested by other procedures such as thru-plane conductivity—which is reflected in the instant testing conditions—in failing to specify the recited testing conditions, Mashtalir fails to explicitly disclose a resistivity of 1–55 ohm•cm under these conditions.
The instant specification notes, though, that the instant resistance is calculated as Rt = Cw*Rw, where Cw represents the content of the conductive material based on the total weight of the active material layer in the target electrode, and Rw represents the electrode resistance value of the target electrode (e.g., p. 26, lines 3–12). Importantly, as seen in the formula, one skilled in the art would recognize that the electrode’s thru-plane resistivity correlates to the electrode’s 1) composition (as such determines conductive-material content and, thus, Cw) and 2) thickness (as such affects Rw by dictating distance electrons must travel).
Regarding 1), as noted above, Mashtalir exemplifies 97 wt% active material and 1% carbon black conductive material in electrode E2 but more broadly allows preferably 0.3~3 wt% (¶ 00148). Moreover, as further seen above, each of the active material, carbon black, CNTs, and PVDF and PTFE binders performs specific functions. Regarding the relation between the binder and conductive material, specifically, the skilled artisan would understand that Mashtalir’s PTFE and PVDF are electrically insulating, and, thus, too much binder would necessarily increase electrode resistance, but enough binder is needed for the above adhesion and mechanical stability. Conversely, the conductive materials would necessarily improve conductivity and, thus, reduce resistance, but too much conductive material would necessarily diminish the other components’ relative contents and, thus, effects. To balance these effects, it would have been obvious to routinely optimize the active material:binder:conductive material ratio (MPEP 2144.05 (II)).
Regarding 2), Mashtalir discloses that the dry electrode film may be 50–300 μm thick (¶ 0198) and, specifically, e.g., 110–120 μm (Ex. E2, ¶ 00254), which is identical to or falls within the spec.’s embodied thickness (p. 41, lines 19 and 20). More importantly, though, the skilled artisan would recognize that the film, i.e., active layer, must be thick enough for suitable capacity without being too thick to excessively increase the distance electrons must travel and, thus, resistance. To balance these effects, then, it would have been obvious to routinely optimize the electrode film’s thickness, including within the apparent overlap/correspondence with the instant disclosure’s embodied thickness (MPEP 2144.05 (II)).
Therefore, in optimizing both 1) the conductive material and binder’s contents as well as 2) the electrode film’s thickness, the skilled artisan would necessarily have to control and, thus, optimize Cw and Rw and, thereby, arrive at the instant resistivity as evaluated by the recited conditions (MPEP 2144.05 (II)).
Regarding claim 29, modified Mashtalir discloses the electrode according to claim 9, wherein the electrode conductive material includes the carbon nanotubes and a dot-like conductive material (Nagai’s CNT plus Mashtalir/Nagai’s CB, respectively; note also that, per instant spec.’s p. 4, line 20, the CB is a dot-like conductor, which is further supported by Mashtalir’s granulated CB in ¶ 0125 (see also Ketjenblack EC-600J, i.e., granulated/dot-like CB, in Mashtalir’s exs. in ¶ 0219)).
Nagai further teaches that, from the viewpoint of reducing internal resistance and achieving more excellent discharge rate and cycle characteristics, the content of CB may be 40–90 mass% relative to the total of the CB and CNT (¶ 0032), yielding a CNT:CB weight ratio of 60:40 to 10:90. Specifically, Nagai teaches that, within this range, CB easily forms a conductive path between active materials, and electrolyte is likely to be maintained near the active material, while the CNT easily form a conductive path on the surface of the active material to enhance both electrical and ion conductivity (¶ 0032).
It would have been obvious to incorporate the CNT-CB mixture at a CNT:CB weight ratio of 60:40 to 10:90 with the reasonable expectation of reducing internal resistance and achieving more excellent discharge rate and cycle characteristics by more easily forming a conductive path on the active material’s surface to enhance (electrical) conductivity and ion conductivity, as taught by Nagai. It would have been further obvious to arrive at the recited range by routinely optimizing the CNT:CB ratio (including within the overlap of 60:40 to 10:90 and the instant 99:1–50:50) to balance the CB’s conductive path between active materials and electrolyte localization with the CNTs’ conductive path atop the active material to achieve optimal electrical and ion conductivity (MPEP 2144.05 (II)).
Response to Arguments
Applicant’s arguments with respect to claim(s) 9 and 29 have been fully considered but are unpersuasive.
Applicant argues that Mashtalir’s process is not substantially similar enough to the instant disclosure’s to support inherency of the binders’ crystallinity values, alleging that Mashtalir blends all electrode components and then extrudes via twin screw, whereas the instant disclosure first mixes the binders and CNT, followed by twin-screw extruding and melt kneading, followed by pulverizing, followed finally by mixing with active material.
Examiner respectfully disagrees that such rebuts the presumed inherency. The instant specification appears to plainly describe that the twin-screw extrusion conditions in themselves may impart the binders’ crystallinity values (see, e.g., p. 25, lines 15–24, which notes that forming the binder-containing extrudate via twin-screw extruder at, e.g., 100–300°C and 50–600 rpm (both of which Mashtalir satisfies, as established above) allows each of the PVDF-based and PTFE binders to achieve ≤ 30% crystallinity—and, ultimately, the recited 0% and greater than 0% to 15%, respectively (see examples)). It is logical that the twin-screw extrusion conditions themselves could afford the recited (low/zero) crystallinities because extrusion is well known to denature crystalline and semi-crystalline polymers. Further, the specification appears devoid of comparative examples showing that Mashtalir’s process would not necessarily achieve the respective crystallinities. Thus, absent additional evidence, the case of inherency appears to remain proper under MPEP 2112.01 (I), making this argument unpersuasive.
Applicant further argues that Mashtalir is silent on a crystallinity percentage, whereas the instant crystallinity improves the CNTs’ dispersion to improve energy density. Examiner first respectfully reiterates that Mashtalir’s process would be expected to yield encompassing or substantially similar crystallinity values for the above reasons. Second, there seems to be no evidence of record demonstrating that 0% crystalline PVDF-based binder and greater than 0% to 15% crystalline PTFE binder are critical to achieving such enhanced dispersion (note, again, that the specification (e.g., p. 16, lines 8–14) appears to treat every value within ≤ 30% crystallinity for each binder the same for achieving the desired effects). Third, it is unclear that such dispersibility would be unexpected given Mashtalir recognizes that twin-screw extrusion, alongside fibrillating/denaturing the binder, also uniformly disperses the conductive carbon through high shear forces (e.g., ¶ 0167, 0170–0172, 0253), and Nagai designs the CNTs’ high BET SSA for uniform dispersibility (¶ 0054). Thus, this argument is unpersuasive.
Regarding Applicant’s argument that the skilled artisan would not have reasonably expected to successfully arrive at the instant crystallization degree due to unpredictable factors affecting crystallinity, like cooling rates and mechanical stretching, such language appears absent from the specification. Such makes this argument appear speculative and, thus, unpersuasive (see MPEP 2145 (I), where Applicant’s arguments cannot substitute for evidence).
Applicant further argues that Mashtalir does not suggest the use of a conductive material besides CB and, thus, fails to motivate the skilled artisan to achieve a CNT-centered conductive network. Examiner respectfully disagrees because Mashtalir plainly allows other conventional conductive aids (¶ 0157–0159). Examiner further echoes that both Nagai and Mashtalir allow as little as 0.1 wt% CB in the electrode (see claim 1), so Examiner respectfully maintains that the skilled artisan would have reasonably expected to successfully arrive at claim 1’s “conductive material consists essentially of the CNT” and achieve improved electrical conductivity and internal resistance as well as higher discharge-rate and cycle characteristics.
Applicant further argues that Mashtalir is directed toward dry electrodes, whereas Nagai uses wet electrodes, where CNT dispersibility is not considered in the same manner. Examiner respectfully disagrees because 1) Mashtalir recognizes that other conductive aids may be used alongside CB and is concerned with conductive-material dispersibility, while Nagai was used to merely teach the benefits of combining CB and CNTs, and 2) Nagai’s electrode is ultimately dried (e.g., ¶ 0089) and, thus, appears compatible with Mashtalir (see MPEP 2145 (IV), where obviousness is based on the prior art’s combined suggestions versus individual teachings).
Applicant further argues that Nagai still fails to motivate replacing CB with CNT such that CNT could be used as the main conductor. Examiner respectfully disagrees because claim 9 appears broader than this argument for the reasons explained above. Namely, it is unclear from the instant disclosure what basic and novel characteristics of CNT may be altered by including other conductive material such that “consists essentially of” seems to effectively be “comprising”, and, independent of this reasoning, the claim’s preamble, with “comprising”, is open to other conductive material like CB regardless of whether “the conductive material consists essentially of the CNT”.
Applicant further argues that Nagai requires both CB and CNT such that the skilled artisan would not be motivated to reach claim 9. Examiner respectfully disagrees for the reasons immediately above.
For new claim 29, see the new grounds of rejection.
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.
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/J.S.M./
Examiner, Art Unit 1751
/Haroon S. Sheikh/Primary Examiner, Art Unit 1751
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