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 .
Response to Arguments
Applicant's arguments filed 1/23/2026 have been fully considered but they are not persuasive.
Applicant argues the present application discloses a positive electrode including a double layer structure where the first mixture layer and the second mixture layer are sequentially stacked on the current collector. In contrast, Han does not teach a first mixture layer and a second mixture layer in the final electrode. In contrast, Han teaches applying a first electrode slurry and then a second electrode slurry on top of the first electrode slurry, drying and pressing the slurries to form a preliminary electrode, and then scraping off the second electrode slurry layer to form the final electrode. The claimed invention recites “a positive electrode for a lithium secondary battery” comprising a “first mixture layer and a second mixture layer,” not a preliminary electrode as taught in Han.
However, Applicant’s arguments are unpersuasive. The Examiner deems that Han teaches a first mixture and a second mixture layer in its final electrode. In Han’s Example 1, Han discloses that a slurry is coated on a current collector and dried. The dried electrode was pressed to a thickness of 114 μm. Then, the 10% upper layer portion based on the thickness of the electrode layer was removed (i.e. only a portion). The resultant electrode is shown schematically in Fig. 5 (i.e. the final product) (Please see paragraph [0066]). This electrode layer has a thickness of 106 μm, and in the electrode, there is an upper layer portion and a lower layer portion having distinct porosities [0067]. That is, Han’s upper and lower layer portions corresponds to Applicant’s first and second mixed layers.
In Han’s Example 2 disclosed in paragraph [0070], a first slurry and a second slurry were coated on a current collector to a thickness of 100 μm and 40 μm, respectively, and dried. The dried electrode was pressed to a thickness of 114 μm. In the resultant preliminary electrode layer, the upper portion formed from the second slurry had a porosity of 18% (i.e. the resultant preliminary electrode is before the partial removal of the electrode layer (i.e. before step S50 in Fig. 1)). Then the first slurry portion was removed. The electrode layer had a thickness of 106 μm. In the electrode (i.e. final product), Han discloses an upper layer portion and a lower layer portion, which corresponds to Applicant’s first and second mixed layers. Please also see paragraph [0072], in which Han discloses that the obtained electrodes have a difference in porosity between the upper layer portion and the lower layer portion. While Han discloses preliminary electrode (i.e. an intermediate product), Han still discloses a finished electrode product.
Please note that the patentability of a product does not depend on its method of production, and thus Han meets the limitation of “a positive electrode for a lithium battery, comprising “a current collector; and a mixture layer formed on one surface or both surfaces of the current collector, wherein the mixture layer is a double-layer structure in which the first mixture layer and a second mixture layer are stacked”.
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.
Claims 1-5, 10, and 11 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20200212428 (“Han et al.”) in view of US Pub. No. 20150372304 (“Hasegawa et al.”)
With regards to Claims 1 and 4, Han et al. teaches a positive electrode for a lithium secondary battery comprising a current collector (320) and a mixture layer (310) formed on one surface or both surfaces of the current collector, wherein the mixture layer is a double-layer structure in which a first mixture layer (310a) and a second mixture layer (310b) are stacked (Abstract, Fig. 5, [0030], and [0031]).
Han et al. teaches the first mixture layer includes a positive electrode active material, a conductive material, and a binder [0030]. Han et al. teaches a porosity of its mixture layer is 20%-70%, wherein the difference in porosity of the first mixture layer and the second mixture layer is 10% or less ([0009]-[0011], [0026], and [0068]-[0072]). It would have been obvious to one of ordinary skill in the art to optimize the porosity of the first mixture layer to be at 40% and a porosity of the second mixture layer to be at 40-44%, for example, in order to have excellent impregnation with an electrolyte ([0012] and [0028]).
Han et al. does not teach the first mixture layer includes a positive electrode additive represented by Chemical Formula 1.
However, Hasegawa et al. teaches a positive electrode for a lithium secondary battery comprising a mixture layer, wherein the mixture layer comprises a positive electrode active material, a positive electrode additive of Li6CoO4, a conductive material, and a binder. The content of the positive electrode additive is 0.1% by mass or more and less than 10% by mass based on a total weight of the first mixture layer (Abstract, [0018]-[0020], [0023], [0024], [0027], and [0029]). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to incorporate Li6CoO4 positive electrode additive in Han et al.’s positive electrode in order to increase the capacity while suppressing degradation of load properties ([0020]-[0022]).
With regards to Claims 2 and 3, Han et al. teaches an average thicknesses of the first and second mixture layers overlap with Applicants claimed thickness ranges and ratio (please see Fig. 5, [0026], and [0070]).
With regards to Claim 5, Han et al. teaches the positive electrode active material is a lithium metal composite oxide of LiNi0.6Mn0.2Co0.2O2 ([0031] and [0068]).
With regards to Claim 10, Han et al. teaches a lithium secondary battery comprising the positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode [0056].
With regards to Claim 11, Han et al. teaches the negative electrode includes a negative electrode current collector and a negative electrode mixture layer which is located on the negative electrode current collector and contains a negative electrode active material. Han et al. further teaches the negative electrode active material includes a carbon material or a silicon material ([0030], [0032], [0047], [0056], and [0066]).
Han et al. does not explicitly teach the negative electrode active material includes a carbon material and a silicon material.
However, Hasegawa et al. teaches its negative electrode active material includes carbon active material and silicon active material [0033]. It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to use a known negative electrode active material of carbon and silicon materials in order to enhance charge/discharge capacity of the battery [0033].
Conclusion
THIS ACTION IS MADE FINAL. 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 LISA CHAU whose telephone number is (571)270-5496. The examiner can normally be reached Monday-Friday 11 AM-730 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Mark Ruthkosky can be reached at (571) 272-1291. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/LC/
Lisa Chau
Art Unit 1785
/Holly Rickman/ Primary Examiner, Art Unit 1785
Prosecution Insights