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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on December 9, 2025 has been entered.
Summary
The Applicant’s arguments and claim amendments received on December 9, 2025 are entered into the file. Currently, claims 1 and 17-19 are amended; claims 5 and 11-15 are withdrawn; claim 6 is cancelled; resulting in claims 1-4, 7-10, and 16-19 pending for examination.
Claim Rejections - 35 USC § 103
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 (i.e., changing from AIA to pre-AIA ) 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.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 4, 7-9, and 16-19 are rejected under 35 U.S.C. 103 as being unpatentable over Yokoshima et al. (US 2020/0106126, previously cited) in view of Zheng et al. (US 2017/0338471, newly cited), Fukumoto et al. (JP 2019-029205, machine translation previously provided), and Pytlik et al. (US 2023/0352765, previously cited).
Regarding claims 1 and 17-19, Yokoshima et al. teaches an electrochemical device (100; non-aqueous electrolyte secondary battery), for example, a lithium-ion secondary battery, comprising an electricity storage device (110; electrode assembly) and a container (120) ([0056]-[0057], Figs. 1-3). The container (120) includes an exterior can (121; bottomed cylindrical exterior) having a cylindrical shape and a sealing body (122; sealing assembly) which is joined to a side wall portion (121b) of the exterior can at an upper end thereof to seal the internal space of the can ([0058]-[0060]), Figs. 1-2).
As shown in Figs. 3-6, the electricity storage device (110) comprises a band-shaped positive electrode (140) and a band-shaped negative electrode (130) which are wound with a separator (150) interposed therebetween [0062]. The positive electrode (140) includes a positive electrode current collector (141) and a positive electrode active material layer (142; positive electrode mixture layer) formed on a surface of the positive electrode current collector ([0071]-[0071], Fig. 6). As shown in Figs. 6-8, the positive electrode further includes three positive electrode lead plates (143) which extend out from the electricity storage device and which serve to electrically connect the sealing body (122) and the positive electrode (140) [0075].
Although Yokoshima et al. generally teaches that the electrochemical device may be a lithium secondary battery comprising a positive electrode active material layer (142) formed on a surface of a positive electrode current collector (141) ([0070]), the reference does not expressly teach that the positive electrode mixture layer contains a positive electrode active material and a phosphorous compound, wherein the active material includes a lithium-containing composite oxide having a layered rock-salt structure, the lithium-containing composite oxide includes secondary particles formed by aggregation of primary particles, and the phosphorous compound adheres to an outer surface of the secondary particles and to a surface of the primary particles located in an interior of the secondary particles.
Zheng et al. teaches high energy density cathode materials, such as NMC cathode materials, with improved discharge capacity and enhanced cycle life (Abstract). Zheng et al. teaches that these NMC cathode materials are layered structured materials according to the R-3m space group (layered rock-salt structure) [0061]. Zheng et al. further teaches that the NMC cathode materials are infused with lithium phosphate, wherein the secondary particles include a coating of lithium phosphate on an outer surface, and the lithium phosphate is diffused into inner cores of the secondary particles [0006]. In particular, Zheng et al. teaches that the lithium phosphate is substantially uniformly distributed along grain boundaries of the primary particles within the secondary particles, thus forming an integrated surface layer that prevents electrolyte diffusion into the inside of secondary particles of the NMC ([0007], [0032], [0054]). Zheng et al. teaches that the internal strain and subsequent electrolyte penetration into secondary particles is a key facilitator of crack formation in cathode materials during electrochemical cycling ([0005], [0032]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the lithium secondary battery of Yokoshima et al. by using the positive electrode active material including a lithium-containing composite oxide having a layered rock-salt structure and having a phosphate compound adhered to both an outer surface of the of the positive electrode active material secondary particles and to a surface of the primary particles located in an interior of the secondary particles, as taught by Zheng et al., given that such lithium-containing composite oxides having a layered rock-salt structure are known to have improved discharge capacity and enhanced cycle life, and given that the application of a phosphorous compound such as lithium phosphate to surfaces of primary and secondary particles as claimed is known to suppress crack formation in cathode materials caused by electrolyte penetration into secondary particles during electrochemical cycling.
Yokoshima et al. and Zheng et al. differ from the claimed invention in that the combination of references does not expressly teach a basis weight of the positive electrode mixture layer. However, Fukumoto et al. teaches a positive electrode for a non-aqueous electrolyte secondary battery comprising a positive electrode mixture layer including a positive electrode active material made of a lithium composite oxide ([0001], [0019]-[0021]). Fukumoto et al. teaches that the basis weight of the positive electrode mixture layer is preferably 30 mg/cm2 or more and 80 mg/cm2 or less ([0032]), equivalent to 300 g/m2 to 800 g/m2, which falls within or overlaps the ranges of claims 1 and 19. Fukumoto et al. teaches that the basis weight is set within this range in order to suppress heat generation in the battery during an internal short circuit, while increasing the capacity and output of the non-aqueous electrolyte secondary battery [0032].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the secondary battery of Yokoshima et al. in view of Zheng et al. by setting a basis weight of the positive electrode mixture layer within the ranges of claims 1 and 19, as taught by Fukumoto et al., in order to suppress heat generation during an internal short circuit, while increasing the capacity and output of the battery.
Although Yokoshima et al. teaches that the electrochemical device may, for example, have a diameter of 18 mm and a length of 65 mm ([0057]), the combination of references does not teach an outer diameter of the cylindrical exterior within the ranges of greater than or equal to 25 mm and less than or equal to 60 mm.
Pytlik et al. teaches an energy storage cell (100) in the form of a cylindrical round cell having an outside diameter of at least 30 mm, comprising an electrode-separator composite (104; electrode assembly) including an anode, a separator, and a cathode (Abstract, Figs. 1-3). Pytlik et al. teaches that cylindrical round cells are particularly suitable for applications with high energy requirements, such as in the automotive sector or for e-bikes or power tools [0189]. The diameter of cylindrical round cells is preferably in the range from 10 mm to 60 mm, where form factors (diameter x height, in mm) of 18x65, 21x70, 32x75, or 32x91 are preferred for applications in supplying power to electric drives in motor vehicles [0190]. Pytlik et al. teaches that larger size cylindrical cells, such as 32x75, 32x91, or 67x172, are particularly effective in applications where temperature management and temperature control capabilities are particularly critical [0193].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the secondary battery of Yokoshima et al. in view of Zheng et al. and Fukumoto et al. by increasing the size of the electrode assembly and the exterior casing such that the outer diameter of the exterior casing is within the ranges of claims 1 and 17, as taught by Pytlik et al., in order to achieve a larger battery with greater energy storage capacity, as desired for particular applications such as supplying power to electric vehicles.
Regarding claim 4, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above, and Yokoshima et al. further teaches that the positive electrode lead plates (143; positive electrode leads) are connected to the positive electrode current collector (141) at areas (positive electrode current collector exposed portions) along an upper end of the current collector where the positive electrode active material layer (142; positive electrode mixture layer) is not applied ([0075], Fig. 6). As shown in Fig. 6, the positive electrode active material layer (142) is present between the exposed portions.
Regarding claim 7, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above. As noted above, Yokoshima et al. does not teach the limitations directed to the phosphorous compound, and Zheng et al. is relied upon to address these features.
As noted above, Zheng et al. teaches lithium phosphate infused into open spaces within the secondary particles of the cathode material, wherein a significant portion (e.g. at least 90%) of grain boundaries between primary particles inside of an infused secondary particle are diffused or filled with lithium phosphate, thus blocking electrolyte diffusion paths, strengthening grain connection, and mitigating cathode degradation ([0052], [0078]). Zheng et al. further teaches that the total weight percentage of the lithium phosphate infused in the secondary particles may be from 0.01 to 5%, or from 0.1 to 0.5% [0052].
Zheng et al. therefore teaches a content of lithium phosphate in the positive electrode mixture layer which overlaps the claimed range of 0.05 to 1 parts by mass relative to 100 parts by mass of an amount of the positive electrode active material. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists. See MPEP 2144.05(I).
Regarding claims 8 and 9, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above. As noted above, Yokoshima et al. does not teach the limitations directed to the phosphorous compound, and Zheng et al. is relied upon to address these features. In particular, as noted above, Zheng et al. teaches that the phosphate compound may be lithium phosphate (Li3PO4), wherein the lithium ion conductive coating can comprise materials that are capable of diffusing into the secondary particles at a temperature below the sintering temperature of the cathode material, such as Li3PO4, Li2HPO4, LiH2PO4, Na3PO4, K3PO4, or the like ([0032], [0058], [0065]).
Regarding claim 16, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above. As noted above, Zheng et al. teaches that the cathode material includes primary and secondary particles, and further teaches that the secondary particles generally have an average diameter of from 2 to 15 microns ([0057]), which falls squarely within the claimed range of 1 to 30 µm. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists. See MPEP 2144.05(I).
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Yokoshima et al. (US 2020/0106126, previously cited) in view of Zheng et al. (US 2017/0338471, newly cited), Fukumoto et al. (JP 2019-029205, machine translation previously provided), and Pytlik et al. (US 2023/0352765, previously cited) as applied to claim 1 above, and further in view of Watanabe et al. (US 2002/0068217, previously cited).
Regarding claims 2 and 3, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above. Although Yokoshima et al. illustrates an embodiment in which the positive electrode lead plates (143) are equally spaced along the positive electrode current collector (141) (Fig. 6), the combination of references does not expressly teach a specific configuration of the positive electrode leads on an upper surface of the electrode assembly.
Watanabe et al. teaches an electrode-rolled battery comprising a rolled body (40; electrode assembly) and a plurality of tabs (50-53; electrode leads), where the rolled body is formed by rolling a band-shaped anode (41) and a band-shaped cathode (42) with a separator between them (43) and is stored in a cylindrical case with a collecting header (54; sealing assembly) connected to the tabs ([0138], [0165], Figs. 1-11). Watanabe et al. teaches that the tabs are arranged either in a line in a diameter direction (arranged in substantially one line in the radial direction) of the rolled body or are equally dispersed around the circumference (arranged at substantially equal intervals around the circumferential direction) of the rolled body, such that the process of gathering the tabs and connecting the tabs to the header is relatively simple compared to the conventional process in which the tabs are arranged irregularly ([0047], [0107], [0171]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the secondary battery of Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. by positioning the positive electrode leads at specific positions along the current collector such that the leads are arranged on the upper surface of the electrode assembly in substantially one line in the radial direction or at substantially equal intervals around the circumferential direction, as taught by Watanabe et al., in order to simplify the process of gathering the electrode leads and connecting the leads to the sealing assembly.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Yokoshima et al. (US 2020/0106126, previously cited) in view of Zheng et al. (US 2017/0338471, newly cited), Fukumoto et al. (JP 2019-029205, machine translation previously provided), and Pytlik et al. (US 2023/0352765, previously cited) as applied to claim 1 above, and further in view of Choi et al. (US 2021/0399297, previously cited).
Regarding claim 10, Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. teaches all of the limitations of claim 1 above. Although Zheng et al. teaches that the cathode material includes primary particles and secondary particles ([0054]), the combination of references does not expressly teach that the positive electrode active material includes a mixture of particles having different median diameters as claimed.
Choi et al. teaches a positive electrode active material and lithium secondary battery, wherein the positive electrode active material is bimodal-type and includes a first lithium composite oxide which is a small particle and a second lithium composite oxide which is a large particle (Abstract). Choi et al. teaches that when small particles and large particles are mixed, voids between the large particles can be filled with small particles to increase the energy density per unit volume ([0009], [0013]). In particular, Choi et al. teaches that the small particle has an average particle diameter (D50) of 8 µm or less, while the large particle has an average particle diameter (D50) of 8 µm or more, preferably 8.5 to 23.0 µm [0036]. Choi et al. therefore teaches ranges for the particle diameters of the large and small particles which overlap the claimed ranges. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists. See MPEP 2144.05(I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the secondary battery of Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. by utilizing a bimodal-type positive electrode active material that includes large and small particles having average particle diameters within the claimed ranges, as taught by Choi et al., in order to optimize the energy density per unit volume of the positive electrode active material.
Response to Arguments
Response-Claim Rejections - 35 USC § 112
The previous rejections of claims 17-19 under 35 U.S.C. 112(b) as being indefinite and under 35 U.S.C. 112(d) as being of improper dependent form are overcome by the Applicant’s amendments to the claims in the response filed December 9, 2025.
Response-Claim Rejections - 35 USC § 103
Applicant’s arguments, see pages 10-16 of the remarks filed December 9, 2025, have been considered but are moot because they do not address the new combination of references being used in the rejections above. In light of the amendments to claim 1, the previous rejections based on Yokoshima et al. in view of Sugiura, Fukumoto et al., and Pytlik et al. are withdrawn, and a new grounds of rejection based on Yokoshima et al. in view of Zheng et al., Fukumoto et al., and Pytlik et al. is applied to address the new combination of limitations.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Itou et al. (US 2007/0082265) teaches a positive electrode material for a non-aqueous electrolyte lithium ion battery comprising an oxide (11; lithium-containing composite oxide) containing lithium and nickel, and a lithium compound (13; phosphorous compound) which is deposited on a surface of the oxide (11) (Abstract, Figs. 1-2). The Li compound has Li ion conductivity and may be lithium phosphate [0038]. The Li compound is deposited on the surface of the Li-Ni oxide so as to cover the surface of the oxide, or so as to sprinkle (i.e., partially cover) the surface of the oxide ([0040], Figs. 1-2). The Li compound may be formed on the surface of primary particles, on the surface of secondary particles composed of aggregated primary particles, or surfaces of both of these particles [0040]. The Li compound serves to prevent decomposition of the electrolysis solution and to prevent swelling of the battery (Abstract, [0041], [0044]).
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/Rebecca L Grusby/Examiner, Art Unit 1785