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
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application No. JP2023-028713, filed on February 27, 2023.
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- 11 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.
The term “periphery” in claims 1 and 11 does not point to a specific area of the negative electrode active material layer and leaves the claims indefinite.
The term “resistance” in claims 1, 10, and 11 is not clearly defined as being either electronic or ionic resistance and leaves the claims indefinite.
Claims 2-22 are indefinite because of their dependence on claim 1.
For the purposes of examination, the “periphery” is interpreted to include points on the electrode active material layer that fall in none of the first high-resistance region A1, the second high resistance region A2, or the central part high-resistance region AM. The term “resistance” is interpreted to include all forms of electronic resistance in the negative electrode active material layer.
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.
Claim(s) 1-4, 6-8, and 10-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sakurai (U.S. Patent Application Publication No. 2017/0222263 A1) in view of Zhao (U.S. Patent Application Publication No. 2025/0070219), further in view of Müller (Journal of Power Sources 440 (2019) 227148).
Regarding claim 1, Sakurai teaches a nonaqueous electrolyte solution secondary battery comprising: a wound electrode body in which a positive electrode with a band shape and a negative electrode with a band shape are stacked across a separator with a band shape and wound (Figures 1 and 2 and [0043] electrode assembly 20, positive electrode 30, separator 50, negative electrode 40); a nonaqueous electrolyte solution ([0043]); a battery case that accommodates the wound electrode body and the nonaqueous electrolyte solution (Figure 1 battery case 10); a positive electrode terminal that is electrically connected to the positive electrode through a positive electrode current collecting part (Figure 1 and [0053] positive current collector 32, positive terminal 60); and a negative electrode terminal that is electrically connected to the negative electrode through a negative electrode current collecting part (Figure 1 and [0045] negative current collector 42, negative terminal 70), wherein the negative electrode includes a negative electrode active material layer including a negative electrode active material (Figure 2 negative electrode active material layer 44).
Sakurai does not explicitly teach a plurality of negative electrode tabs provided at one end part in a winding axis direction, the plurality of negative electrode tabs are connected to the negative electrode current collecting part in a state of being stacked and bent.
To solve the problem of providing a wound battery, Zhao teaches a battery comprising a plurality of negative electrode tabs provided at one end part in a winding axis direction, the plurality of negative electrode tabs (Figures 5-7 plurality of tabs 16A) are connected to the negative electrode current collecting part in a state of being stacked and bent ([0093] describes the tab portion 11A being bent and welded to the current collecting plate 230).
Zhao teaches using a plurality of negative electrode tabs that are stack and bent results in improved electrical contact with the negative terminal and a more compact battery cell ([0096]). Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to have combined the battery assembly of Sakurai with the stacked and bent tab structure of Zhao.
Modified Sakurai does not explicitly teach the negative electrode active material layer includes a first high-resistance region extending from the one end part toward a central part in the winding axis direction and having a resistance value that is 1.5 times or more higher than that in a periphery, and when a length of the negative electrode active material layer is La and a length of the first high-resistance region is L1 in the winding axis direction, a ratio (L1/La) of the length L1 of the first high-resistance region to the length La of the negative electrode active material layer is 0.35 or less.
However, Sakurai teaches that the negative electrode of his invention should be designed to avoid non-uniformity in structure (as shown in Figure 6 and [0013] and [0022]). Sakurai specifically recognizes that non-uniformity in a negative electrode surface results in electrode deterioration, increased resistance, and a decrease in battery performance ([0013] and [0022]).
To solve the same problem of providing a lithium-ion battery, Müller teaches that applying mechanical pressure to an electrode stack assembly after formation suppresses resistance in the high frequency region of an impedance measurement (Figure 5 a and c), especially when initially charging to a state of charge of 10%. Müller also teaches that applying mechanical pressure to the electrode assembly results in a more uniform negative electrode surface (Figure 8). Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to apply mechanical pressure to the electrode assembly of modified Sakurai, in order to create a more uniform electrode and suppress resistance, as taught by Müller.
Further, because Müller teaches that the amount of mechanic pressure applied to the electrode assembly affects uniformity and resistance of the electrode (Figures 5 a,c and 8), it is the examiner’s position that one of ordinary skill in the art would have been motivated to optimize the pressure applied to the assembly of modified Sakurai, based on the disclosure of Müller that such pressure improves the uniformity of the negative electrode active material layer. It is the examiner’s position that this routine optimization of applied pressure would have lead one of ordinary skill in the art at the time the instant application was filed to have arrived at a pressing pressure that would result in a structure in which a first high-resistance region extending from the one end part toward a central part in the winding axis direction and having a resistance value that is 1.5 times or more higher than that in a periphery, and when a length of the negative electrode active material layer is La and a length of the first high-resistance region is L1 in the winding axis direction, a ratio (L1/La) of the length L1 of the first high-resistance region to the length La of the negative electrode active material layer is 0.35 or less, without undue experimentation.
It is further noted that paragraphs [0052] and [0080]as well as Table 1 of the instant specification recognize that the application of pressure to the electrode stack of the instant invention is critical for forming the claimed invention.
Regarding claim 2, the length of the negative electrode active material layer in the winding axis direction represents a mere scaling up/change in proportion of the prior art and is not patentably distinct from the prior art, Gardner v. TEC Syst., Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984).
Regarding claim 3, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described above does not teach the negative electrode necessarily includes a negative current collector containing copper or a copper alloy.
Sakurai goes on to teach the negative electrode may include a negative current collector containing copper or a copper alloy ([0063] copper is given as an example of a suitable negative current collector material).
Sakurai teaches that copper foil is a suitable material for a negative electrode current collector. Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to use copper as a negative current collector.
Regarding claim 4, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described above does not teach the positive electrode necessarily includes a lithium manganese containing complex oxide as a positive electrode material.
Sakurai goes on to teach the positive electrode may include a lithium manganese containing complex oxide as a positive electrode active material ([0055] describes LiNi1/3Co1/3Mn1/3O2 as a positive electrode material).
Sakurai teaches that LiNi1/3Co1/3Mn1/3O2 is a preferred positive electrode material for its excellent thermal stability and high energy density ([0055]). Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to use LiNi1/3Co1/3Mn1/3O2 as a positive electrode active material.
Regarding claim 6, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described does not teach the nonaqueous electrolyte solution necessarily includes a lithium salt containing a phosphorous element.
Sakurai goes on to teach the nonaqueous electrolyte solution may include a lithium salt containing a phosphorous element ([0076]-[0078] describes multiple phosphorous containing lithium salts).
Sakurai teaches that a phosphorous containing lithium salt would be suitable to be used in a nonaqueous electrolyte. Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to use a phosphorous containing lithium salt in the nonaqueous electrolyte.
Regarding claim 7, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described does not teach the nonaqueous electrolyte solution necessarily includes a lithium salt containing a boron element.
Sakurai goes on to teach the nonaqueous electrolyte solution may include a lithium salt containing a boron element ([0076]-[0078] describes multiple boron containing lithium salts).
Sakurai teaches that a boron containing lithium salt would be suitable to be used in a nonaqueous electrolyte. Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to use a boron containing lithium salt in the nonaqueous electrolyte.
Regarding claim 8, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described does not teach the nonaqueous electrolyte solution necessarily includes a lithium salt containing a sulfur element.
Sakurai goes on to teach the nonaqueous electrolyte solution may include a lithium salt containing a sulfur element ([0076] describes multiple sulfur containing lithium salts).
Sakurai teaches that a sulfur containing lithium salt would be suitable to be used in a nonaqueous electrolyte. Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to use a sulfur containing lithium salt in the nonaqueous electrolyte.
Regarding claim 10, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described does not teach when a resistance distribution is measured along the winding axis direction in a part of the negative electrode active material layer where the first high-resistance region is not formed, a resistance value at a central position that is 0.5La from the one end part is 1.5 times or less a resistance value at a reference position that is 0.25La from the one end part.
Sakurai indicates only a limited amount of electrolyte solution is able to access the center of the electrode assembly in the winding axis (middle region of Figure 6). This limited amount of electrolyte would inherently lead to a thinner solid electrolyte interface film, causing a higher resistance in the center of the negative electrode in the winding axis. Therefore, a tightly wound electrode assembly of sufficient size would inherently include a high resistance region in the central portion of the electrode. It is the examiner’s position that one having ordinary skill in the art at the time the instant application was filed would have arrived at a structure in which when a resistance distribution is measured along the winding axis direction in a part of the negative electrode active material layer where the first high-resistance region is not formed, a resistance value at a central position that is 0.5La from the one end part is 1.5 times or less a resistance value at a reference position that is 0.25La from the one end part.
Regarding claim 11, Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai as described does not teach the positive electrode includes a plurality of positive electrode tabs provided at the other end part in the winding axis direction, the plurality of positive electrode tabs are connected to the positive electrode current collecting part in a state of being stacked and bent.
To solve the problem of providing a wound battery, Zhao teaches the positive electrode includes a plurality of positive electrode tabs provided at the other end part in the winding axis direction (Figures 5-7 plurality of tabs 16B), the plurality of positive electrode tabs are connected to the positive electrode current collecting part in a state of being stacked and bent collector ([0093] describes the tab portion 11B being bent and welded to the current collecting plate 230).
Zhao teaches using a plurality of positive electrode tabs that are stack and bent results in improved electrical contact with the positive terminal and a more compact battery cell ([0096]). Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to have combined the battery assembly of modified Sakurai with the stacked and bent tab structure of Zhao.
It is the examiner’s position that one of ordinary skill in the art, as similarly described with regard to claim 1, would have been motivated to optimize the pressure applied to the assembly of modified Sakurai, based on the disclosure of Müller that pressure improves the uniformity of the negative electrode active material layer. It is the examiner’s position that this routine optimization of applied pressure would have lead one of ordinary skill in the art at the time the instant application was filed to have arrived at a pressing pressure that would result in a structure in which the negative electrode active material layer includes a second high-resistance region extending from the other end part toward the central part in the winding axis direction and having a resistance value that is 1.5 times or more higher than that in a periphery, and when a length of the second high-resistance region is L2 in the winding axis direction, a ratio (L2/La) of the length L2 of the second high-resistance region to the length La of the negative electrode active material layer is 0.35 or less, without undue experimentation.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sakurai in view of Zhao, further in view of Müller, further in view of Minami (U.S. Patent Publication No. 2014/0045013).
Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 4 as described above.
Modified Sakurai does not teach the positive electrode active material contains a zirconium element.
Minami does teach the positive electrode active material contains a zirconium element ([0069] recites the incorporation of zirconium in a positive electrode material).
Minami is analogous to the present application as it relates to a wound electrode assembly of a battery. Minami teaches that a zirconium element may be incorporated into a lithium containing transition metal composite oxide for suitable use as a positive electrode active material. Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to incorporate a zirconium element into the positive electrode active material.
Claim(s) 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sakurai in view of Zhao, further in view of Müller, further in view of Takami (U.S. Patent No 6465125).
Sakurai in view of Zhao, further in view of Müller meets all limitations of claim 1 as described above.
Modified Sakurai does not teach the negative electrode and the separator are attached to each other by an adhesive layer.
Takami does teach the negative electrode and the separator are attached to each other by an adhesive layer (Col. 2 lines 40-45 describes the adhesion of a negative electrode and separator).
Takami is analogous to the present application as it related to a wound electrode assembly of a battery. Takami teaches that a negative electrode and separator may be adhered to each other in a wound electrode assembly in order to reduce the risk of a short circuit in the cell (Col. 10 lines 23-29). Therefore, it would have been obvious to a person having ordinary skill in the art at the time of filing to incorporate an adhesive layer between the negative electrode and separator.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Mok (KR 100824869 B1) describes performing the initial charging of a wound battery electrode assembly under mechanical pressure.
Domoto (US 20250062425) describes performing the initial charging of a battery electrode assembly under mechanical pressure in order to improve the quality of the solid electrolyte interface.
McCleary (David A.H. McCleary et al 2013 J. Electrochem. Soc. 160 A1931) describes the impact on heat and current density of having a plurality of electrode tabs in a wound electrode assembly.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRIAN G. DIAMOND whose telephone number is (571)270-5888. The examiner can normally be reached Monday - Friday 8:30 am - 5 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sam Xiao Zhao can be reached at (571) 270-5343. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/B.G.D./ Examiner, Art Unit 1744
/SADIE WHITE/ Primary Examiner, Art Unit 1721
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