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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-16, drawn to a positive electrode active material with a core-shell structure in the reply filed on 08/03/2026 is acknowledged.
Claims 17-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group II, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 08/03/2026.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 12/02/2023, 07/03/2024, 08/30/2024, 12/31/2024, 05/01/2025, 08/20/2025, 12/16/2025, 03/18/2026, and 06/24/2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
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.
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 1-8, 11-12, and 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Wu (US 20160190584 A1) and further in view of Chen et al. (CN 114256448A, citation from enclosed machine translation), H. Wu et al. (US 20160260965 A1), Hu et al (CN 108511715 A, citation from enclosed machine translation), and Xu et al. (Xu, Ming, et al. "Highly crystalline alumina surface coating from hydrolysis of aluminum isopropoxide on lithium-rich layered oxide.", 2015, Journal of Power Sources, 281, 444-454.)
Regarding claim 1, Wu teaches a limitation wherein a positive electrode active material with a core-shell structure, comprising a core and a shell covering the core, wherein: the core comprises Li1+xMn1-yAyP1-zRzO4, wherein: x is any value in a range from −0.100 to 0.100; y is any value in a range from 0.001 to 0.500; z is any value in a range from 0.001 to 0.100; A is one or more elements selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb, and Ge; and R is one or more elements selected from B, Si, N, and S; and a coating layer comprises carbon.
Specifically, Wu teaches a positive electrode active material comprising LiMn0.8Fe0.2P0.93Si0.07O4 as Comparative Sample D3 ([0061], Table 2) which corresponds to the core, and further teaches a carbon coating layer on the positive electrode active material ([0010]) which corresponds to a shell. Wu's composition corresponds to the claimed core composition Li1+xMn1-yAyP1-zRzO4 , wherein x=0, y=0.2, A=Fe, z=0.07, and R= Si. Each of these values and elements falls within the presently claimed ranges and selections. Accordingly, Wu teaches the claimed positive electrode active material core composition and further teaches coating the positive electrode active material with carbon.
Wu, however, does not teach the shell comprises a first coating layer covering the core and a second coating layer covering the first coating layer, wherein: the first coating layer comprises a crystalline pyrophosphate MaP2O7 and a crystalline oxide M′bOc, wherein: a is greater than 0 and less than or equal to 4; b is greater than 0 and less than or equal to 2; c is greater than 0 and less than or equal to 5; M is one or more elements selected from Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al; and M' is one or more elements selected from alkali metals, alkaline earth metals, transition metals, group IIIA elements, group IVA elements, lanthanides, and Sb; and the second coating layer comprises carbon.
However, Chen teaches a lithium manganese iron phosphate composite material comprising an inner core 10 and a cladding/coating layer 20 covering the inner core, wherein the cladding layer includes at least one barrier material layer 21 and at least one lithium manganese iron phosphate layer 22 (page 3, lines 16–20; Fig. 1). Chen teaches that the barrier material layer may comprise materials selected from metal oxides, metaphosphates, and pyrophosphates (page 2, lines 10-11; page 4, lines 52-60). Chen further teaches that the barrier material layer blocks self-diffusion of manganese caused by differences in manganese content between inner and outer layers, facilitates a differential distribution of manganese, avoids direct contact between the electrolyte and manganese, and suppresses dissolution of manganese (page 4, lines 52–55).
Chen specifically teaches metal oxides including aluminum oxide (page 4, lines 56-57). Chen explains that such metal oxides have good stability and are conducive to forming a long-term stable coating of the inner core, thereby providing the lithium manganese iron phosphate composite material with long-term high-efficiency performance and service life (page 4, lines 56–60). Chen's disclosure of aluminum oxide (Al2O3) corresponds to the claimed oxide M′bOc, wherein M′= Al from group IIIA, b=2, and c=3.
Chen also teaches pyrophosphate barrier materials, thereby teaching the use of both metal oxide and pyrophosphate materials as barrier/coating materials for a lithium manganese iron phosphate active-material core (page 2, lines 10-11; page 4, lines 52-60).
Chen further teaches providing a carbon coating layer over the composite material (page 2, lines 6–7). Chen explains that the carbon coating layer improves electrical conductivity of the lithium manganese iron phosphate composite material and ensures charge-discharge performance (page 6, lines 58-60). Thus, Chen provides express teaching of an arrangement in which a protective barrier/cladding structure is provided on the active-material core and a carbon coating is subsequently provided over the composite material.
Further, Wu and Chen are considered to be analogous to the claimed invention because both concern lithium manganese iron phosphate positive electrode active materials and address improvement of their performance.
Therefore, 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 positive electrode active material of Wu to include the protective barrier/coating structure of pyrophosphate and oxide, taught by Chen between Wu's active-material core and carbon coating to protect the active material by reducing manganese dissolution and direct electrolyte contact and to provide stability and long-term performance (page 4, lines 52-60). A person of ordinary skill therefore would have been motivated to incorporate Chen's barrier layer into Wu's coated active material to obtain these expressly taught protective and stability benefits, while retaining the outer carbon coating to provide the conductivity benefits taught by both Wu and Chen.
Wu as modified by Chen, however, does not teach specifically a crystalline pyrophosphate MaP2O7, wherein: a is greater than 0 and less than or equal to 4; and M is one or more elements selected from Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al.
However, H. Wu teaches a coated cathode active material comprising an electrochemically active material serving as a core and an electrochemically inert material forming a coating or shell on the core ([0013]). H. Wu teaches coating materials represented generally by AxDy, wherein A may be selected from Li, Al, Mg, Fe, Cu, Zn, Cr, Mn, Ni, Ag, Ca, Na, K, In, Ga, Ge, V, Mo, Nb, Si, Ti, Zr, or mixtures thereof, and wherein D may include O2-, P2O74-, PO43-, or mixtures thereof ([0010, 0014, 0022]). H. Wu explains that such surface coating are effective for improving cycle life and safety of lithium-ion cells ([0004]).
Accordingly, H. Wu teaches both metal oxide and metal pyrophosphate coating materials for an active cathode-material core. Moreover, the metals disclosed by H. Wu substantially overlap the metals recited in claim 1. In particular, H. Wu's disclosed metals include members of the claimed M group for MaP2O7, including Li, Fe, Ni, Mg, Cu, Zn, Ti, Ag, Zr, Nb, and Al, and H. Wu's disclosed metals likewise fall within the broad classes recited for M′ of the claimed oxide M′bOc.
Thus, H. Wu reinforces Chen's teaching that both oxide and pyrophosphate materials are suitable protective coating materials for cathode active-material particles and further provides metal selections falling within the presently claimed M and M′ selections.
Further, modified Wu and H. Wu are considered to be analogous to the claimed invention because both are in the same field of lithium manganese iron phosphate positive electrode active materials.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention to select the oxide and pyrophosphate coating materials taught by H. Wu for use in the barrier/coating layer of the modified Wu positive electrode active material for improving cycle life and safety of lithium-ion cells ([0004]). Chen already teaches the use of both metal oxide and pyrophosphate barrier materials on lithium manganese iron phosphate active material and identifies their protective and stability functions. H. Wu independently teaches metal oxide and P2O74--containing metal compounds (i.e., metal pyrophosphate) as suitable electrochemically inert coating materials for cathode active-material cores and identifies metals falling within the presently claimed selections.
The combination of Wu, Chen, and H. Wu therefore teaches a positive electrode active material having the claimed core composition, a protective first coating/barrier layer comprising metal oxide and metal pyrophosphate materials having metals falling within the claimed selections, and an outer carbon-containing coating. Modified Wu, however, does not teach that the pyrophosphate and oxide components are crystalline.
However, Hu teaches surface modification of lithium-ion battery positive electrode active material with a lithium pyrophosphate coating and expressly teaches controlling the preparation and annealing conditions to obtain lithium pyrophosphate having a good crystalline phase (page 2, lines 38-44). Hu's lithium pyrophosphate falls within the claimed M elements. Hu further teaches annealing in an oxygen-containing atmosphere and explains that a coating material having a pure crystal phase may be obtained under the disclosed annealing conditions. Hu teaches that controlling the heating rate and annealing time improves the crystal-phase purity of the coating (page 4, lines 4-22).
Hu further explains that a coating having a good crystalline phase stabilizes the crystal structure, prevents the active material from directly contacting the electrolyte, and inhibits interfacial reactions on the surface of the material. Hu additionally teaches that lithium pyrophosphate facilitates lithium-ion diffusion and interfacial charge transfer (page 5, lines 7-14).
Further, modified Wu and Hu are considered to be analogous to the claimed invention because both are in the same field of lithium-ion battery positive electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to provide the metal pyrophosphate component taught by modified Wu in the crystalline form taught by Hu to stabilize the crystal structure, reduce direct electrolyte contact and undesirable interfacial reactions, and promote lithium-ion diffusion and interfacial charge transfer (Hu page 5, lines 7-14).
Modified Wu, however, does not teach that the metal oxide component of the first coating layer is crystalline.
However, Xu teaches highly crystalline alumina coating layer on the surface of a lithium ion cathode active material. Xu’s Al2O3 corresponds to the claimed crystalline oxide. Xu further teaches that the highly crystalline Al2O3 coating improves cycling stability and reduce voltage decay, and attributes the improvements to suppression of structural degradation and phase transformation of the cathode material (abstract, page 446, first column; page 452, first column).
Further, modified Wu and Xu are considered to be analogous to the claimed invention because both are in the same field of lithium-ion battery positive electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention to provide the metal oxide component of the protective coating taught by modified Wu (i.e., aluminum oxide taught by Chen as applied to modified Wu above) in the crystalline form taught by Xu in order to improve cycling stability and reduce voltage decay (Xu abstract, page 446, first column; page 452, first column).
Accordingly, it would have been obvious to one of ordinary skill in the art to modify Wu in view of Chen, H. Wu, Hu, and Xu to provide the claimed positive electrode active material having a core-shell structure. In combination, Wu teaches the claimed lithium manganese phosphate core material and carbon coating; Chen modifies Wu by providing a barrier layer between the core and carbon and teaches Aluminum oxide and pyrophosphate as suitable barrier materials; H. Wu further teaches a coating comprising mixtures of oxide and pyrophosphate materials and identifies metals falling within the claimed M group, as a suitable metal for the pyrophosphate coating composition; Hu teaches modifying the pyrophosphate component to be crystalline; and Xu teaches modifying the Al₂O₃ oxide component to be highly crystalline, thereby resulting in the claimed core-shell material comprising the core, a first coating layer comprising crystalline pyrophosphate and crystalline oxide, and a second carbon coating layer covering the first coating layer. Thereby, all limitations of claim 1 are rendered obvious.
Regarding claim 2, modified Wu teaches all limitations of claim 1 as stated above. Wu further teaches a limitation wherein a ratio of y to 1−y in the core is 1:10 to 10:1 ([0061], Table. 2). Wu specifically teaches y equal to 0.2 for the disclosed D3 composition (as cited in claim 1 rejection above). Accordingly, the ratio of y to 1-y is 0.2:0.8, or 1:4, which falls within the claimed range of 1:10 to 10:1. It has been held that in the case where 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 claim 3, modified Wu teaches all limitations of claim 1 as stated above. Wu further teaches a limitation wherein a ratio of z to 1−z in the core is 1:9 to 1:999 ([0061], Table. 2). Wu specifically teaches z equal to 0.07 for the disclosed D3 composition (as cited in claim 1 rejection above). Accordingly, the ratio of z to 1-z is 0.07:0.93, or 1:13.29, which falls within the claimed range of 1:9 to 1:999. It has been held that in the case where 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 claim 4, modified Wu teaches all limitations of claim 1 as set forth above. Chen further teaches the limitation wherein a coating amount of the first coating layer is greater than 0% by weight and less than or equal to 7% by weight.
Specifically, Chen teaches that the barrier material accounts for 0.3%–0.6% of the mass of the core material (page 8, lines 5-8). Chen further teaches that the barrier material layer is formed on and coats the inner core by solid-phase sintering (page 8, lines 10-22). Chen teaches that using the disclosed amount facilitates complete coating of the inner core during solid-phase sintering, thereby improving the overall performance of the lithium manganese iron phosphate composite material (page 8, lines 5–14). Thus, Chen's disclosed coating amount of 0.3%–0.6% falls within the claimed range of greater than 0% by weight and less than or equal to 7% by weight. It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to employ Chen's disclosed amount of barrier material in the first coating layer of the modified Wu material to facilitate complete coating of the inner core during solid-phase sintering, thereby improving the overall performance of the lithium manganese iron phosphate composite material (Chen page 8, lines 5-14).
Regarding claim 5, modified Wu teaches all limitations of claim 1 as set forth above. H. Wu further teaches a limitation wherein a weight ratio of the pyrophosphate to the oxide in the first coating layer is 1:3 to 3:1.
Specifically, H.Wu teaches that the coating may comprise a mixture of two or more coating materials, including metal oxides and P2O7- containing materials ([0010, 0014, 0022, 0092]), and teaches that the composition of the coating layer may be adjusted or varied ([0073, 0093, 0096]). Accordingly, H. Wu teaches that the relative amount of the coating components are adjustable parameters. H. Wu further teaches that such electrochemically inert coatings are useful for improving cycle life and safety and protecting the active material from exposure to the electrolyte ([0004]). The particular weight ratio of the pyrophosphate to the oxide represents no more than optimization of known variables through routine experimentation to achieve the desired cycle life and safety. Routine experimentation is within the ambit of a person having ordinary skill in the art per MPEP 2144.05(II).
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date to find the optimal relative amounts of the pyrophosphate and oxide components, including a weight ratio within the claimed range of 1:3 to 3:1, through routine experimentation to obtain a suitable balance of their protective properties and thereby protecting the active material from exposure to the electrolyte ([0004]). Determining an optimum or workable proportion of known coating components through routine experimentation would have been within the ordinary skill in the art, absent evidence that the claimed ratio is critical or produces unexpected results.
Regarding claim 6, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu further teaches a limitation wherein the pyrophosphate in the first coating layer has an interplanar spacing of 0.293–0.326 nm, and an included angle of 26.41°–32.57° for a [111] crystal orientation.
As to Claim 6, it is the position of the Office that the active material of modified Wu intrinsically satisfies the claimed conditions, given that the structure and material compositions used in the prior art (as applied above to arrive at the rejection of claim 1) and the claimed invention are substantially the same, see MPEP 2112.01.
Specifically, Hu (as applied to modified Wu in regard to claim 1 above) teaches controlling the annealing conditions to improve the crystal-phase purity of the lithium pyrophosphate coating and to obtain a relatively pure crystalline coating material (page 4, lines 16-22). Hu further teaches that a coating material having a good crystalline phase stabilizes the crystal structure, prevents the active material from directly contacting the electrolyte, inhibits interfacial reactions on the surface of the material, and promotes lithium-ion diffusion and interfacial charge transfer (page 5, lines 7-14).
Hu therefore recognizes the crystallinity of the pyrophosphate coating as a result-effective variable, because Hu expressly teaches controlling annealing conditions to improve crystal-phase purity and further identifies the beneficial structural and electrochemical effects resulting from a coating having a good crystalline phase. Accordingly, the annealing conditions and resulting crystallinity of the pyrophosphate coating could be adjusted to obtain a desired crystalline pyrophosphate coating having beneficial structural properties.
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to optimize the annealing conditions of the modified Wu material so as to optimize the crystallinity and crystal-phase purity of the pyrophosphate coating in order to obtain benefits of improved crystal-structure stability, reduced direct contact between the active material and electrolyte, reduced interfacial reactions, and improved lithium-ion diffusion and interfacial charge transfer (Hu page 5, lines 7-14). Where the modified prior-art material comprises the same crystalline pyrophosphate coating as recited in claim 1 and is prepared under conditions selected to obtain the crystalline phase taught by Hu, the interplanar spacing and included angle associated with the [111] crystal orientation are intrinsic crystallographic properties of that crystalline material. Thus, absent evidence demonstrating that the substantially identical crystalline pyrophosphate possesses different crystallographic properties, the claimed interplanar spacing of 0.293–0.326 nm and included angle of 26.41°–32.57° would be inherently satisfied by the resulting crystalline pyrophosphate, see MPEP 2112.01. Moreover, Discovering the optimum or workable ranges of a result-effective variable (i.e., optimal crystalline properties to achieve above-cited beneficial results) involves only routine skill in the art. See MPEP 2144.05(II)
Regarding claim 7, modified Wu teaches all limitations of claim 1 as set forth above. Hu further teaches a limitation wherein a crystallinity of the pyrophosphate in the first coating layer is 10% to 100%.
Specifically, Hu (as applied to modified Wu in regards to claim 1 above) teaches controlling the annealing conditions to improve the crystal-phase purity of the lithium pyrophosphate coating and to obtain a relatively pure crystalline coating material (page 4, lines 16-22). Hu further teaches that a coating material having a good crystalline phase stabilizes the crystal structure, prevents the active material from directly contacting the electrolyte, inhibits interfacial reactions on the surface of the material, and promotes lithium-ion diffusion and interfacial charge transfer (page 5, lines 7-14).
Hu therefore recognizes the crystallinity of the pyrophosphate coating as a result-effective variable, because Hu expressly teaches controlling annealing conditions to improve crystal-phase purity and further identifies the beneficial structural and electrochemical effects resulting from a coating having a good crystalline phase.
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to optimize the annealing conditions of the modified Wu material so as to increase the crystallinity of the pyrophosphate coating, including to a crystallinity within the claimed range of 10% to 100%, in order to obtain benefits of improved crystal-structure stability, reduced direct contact between the active material and electrolyte, reduced interfacial reactions, and improved lithium-ion diffusion and interfacial charge transfer (Hu page 5, lines 7-14). Discovering the optimum or workable ranges of a result-effective variable involves only routine skill in the art. See MPEP 2144.05(II)
Regarding claim 8, modified Wu teaches all limitations of claim 1 as set forth above. Wu further teaches a limitation wherein a coating amount of the second coating layer is greater than 0% by weight and less than or equal to 6% by weight, based on a weight of the core.
Specifically, Wu teaches a carbon coating and discloses preferred carbon contents of 5%, 4%, 3%, 2%, 1.5%, and 1% by weight of the positive electrode material ([0011]). Although Wu expresses the carbon content based on the total positive electrode material, whereas claim expresses the coating amount based on the weight of the core, Wu teaches the positive electrode material as comprising the active-material core and carbon coating. Thus, for example, Wu's 5 wt.% carbon based on the total coated material corresponds to approximately 5.26 wt.% based on the weight of the core (since 5/(100-5)=5/95=0.0526), which falls within the claimed range of greater than 0 wt.% and less than or equal to 6 wt.%. It has been held that in the case where 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 claim 11, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu further teaches a limitation wherein a lattice change rate of the positive electrode active material before and after complete lithium deintercalation and intercalation is 7.5% or less.
As to Claim 11, it is the position of the Office that the active material of modified Wu intrinsically satisfies the claimed conditions, given that the structure and material compositions used in the prior art (as applied above to arrive at the rejection of claim 1) and the claimed invention are substantially the same, see MPEP 2112.01.
Regarding claim 12, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu further teaches a limitation wherein a valence state of surface oxygen of the positive electrode active material is −1.83 or less.
As to Claim 12, it is the position of the Office that the active material of modified Wu intrinsically satisfies the claimed conditions, given that the structure and material compositions used in the prior art (as applied above to arrive at the rejection of claim 1) and the claimed invention are substantially the same, see MPEP 2112.01.
Regarding claim 14, modified Wu teaches all limitation of claim 1 as stated above. H. Wu further teaches a positive electrode plate comprising: a positive electrode current collector; and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, wherein the positive electrode film layer comprises the positive electrode active material according to claim 1 ([0036, 0125]).
Specifically, H. Wu teaches a cathode comprising the coated cathode active material and a binder, wherein the cathode may further comprise a current collector ([0036]). H. Wu further teaches forming the cathode by applying the cathode material onto a current collector ([0125]). Thus, H. Wu teaches a positive electrode comprising a current collector and an active-material-containing layer disposed on a surface of the current collector.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the modified Wu positive electrode active material into the electrode structure taught by H. Wu, including disposing a film layer containing the active material on a current collector, because H. Wu teaches such an electrode configuration for incorporating cathode active material into a lithium-ion battery ([0002, 0125] of H. Wu ). Such a modification would have constituted the simple addition of known electrode components taught by H. Wu to the electrode of modified Wu, with the components expected to successfully perform their known functions and predictably form the claimed positive electrode plate (see MPEP 2143(I)B).
Regarding claim 15, modified Wu teaches all limitation of claim 1 as stated above. Wu further teaches a secondary battery, comprising the positive electrode active material according to claim 1 (Wu [0034]: Li-ion battery with positive electrode material).
Regarding claim 16, modified Wu teaches all limitation of claim 15 as stated above. Modified Wu further teaches a battery module, comprising the secondary battery according to claim 15.
Specifically, Wu teaches that Li-ion batteries are increasingly applied in electrical vehicles, energy storage, and the like ([0002]). Although Wu does not teach a battery module comprising the secondary battery, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the secondary battery of modified Wu into a battery module because Wu expressly identifies electrical vehicles and energy-storage systems as applications for Li-ion batteries ([0002]), for which arranging battery cells into a battery module was a known and predictable battery configuration. Accordingly, incorporating the secondary battery into a battery module would have constituted the predictable use of a known battery configuration for vehicle and energy-storage applications, with a reasonable expectation of success.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as modified by Chen, H. Wu, Hu , and Xu, as applied to claim 1 above, and further in view of Jen et al. (US 20210119211 A1).
Regarding claim 9, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu does not teach a limitation wherein A is at least two elements selected from Fe, Ti, V, Ni, Co, and Mg.
However, Jen teaches a doped lithium manganese iron phosphate-based particulate for a cathode of a lithium-ion battery containing both Fe, and Mg ([0033-0043]). Jen’s Example 1 further expressly prepares a lithium manganese iron phosphate material containing both Fe, and Mg ([0063]). Thus, Jen teaches an LMFP core material containing at least two elements, Fe, and Mg, selected from the group recited in claim 9.
Further, modified Wu and Jen are considered to be analogous to the claimed invention because both are in the same field of lithium manganese iron phosphate positive electrode active materials.
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to incorporate Mg in addition to Fe into the LMFP core of modified Wu because Jen expressly teaches Mg as a suitable constituent of the same type of lithium manganese iron phosphate cathode material. Combining known equivalent constituents taught in the art to be useful for the same purpose would have been obvious to one of ordinary skill in the art See MPEP 2144.06. Further, the selection of Mg based on its known suitability for an intended use in an LMFP cathode material would have been obvious. See MPEP 2144.07
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as modified by Chen, H. Wu, Hu, and Xu, as applied to claim 1 above, and further in view of Gardiner et al. (Gardiner, Grahame R., and M. Saiful Islam. "Anti-site defects and ion migration in the LiFe0.5Mn0.5PO4 mixed-metal cathode material.", 2010, Chemistry of Materials, 22.3, 1242-1248.)
Regarding claim 10, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu does not teach a limitation wherein the positive electrode active material has a Li/Mn antisite defect concentration of 5.1% or less.
However, Gardiner teaches antisite defects in the mixed-metal olivine cathode material LiFe0.5 Mn0.5PO4. Gardiner teaches that the Li/M antisite pair, wherein M is Fe or Mn, is the most favorable intrinsic defect in LiFe0.5 Mn0.5PO4 and that, even at low temperatures, a small percentage of approximately 1% of Fe or Mn ions is expected to occupy Li sites (page 1245, section 3.1). Gardiner further concludes that a small population of less than 2% of Li+ and Fe2+ or Mn2+ ions is expected to exchange sites (page 1247, section 4). Gardiner further teaches that such antisite defects impede lithium-ion diffusion to varying degrees along the [010] channels (abstract, page 1247). Accordingly, Gardiner teaches Li/transition-metal antisite defects, including Li/Mn antisite defects, at concentrations falling within the claimed upper limit of 5.1%. It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Further, modified Wu and Gardiner are considered to be analogous to the claimed invention because both are in the same field of lithium manganese iron phosphate positive electrode active materials.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide the modified Wu positive active material with a low Li/Mn antisite defect concentration as taught by Gardiner in order to reduce impediments to lithium-ion diffusion and facilitate lithium-ion transport (abstract, page 1247).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as modified by Chen, H. Wu, Hu, and Xu, as applied to claim 1 above, and further in view of C. Xu (CN 106816582 A, citation from enclosed machine translation).
Regarding claim 13, modified Wu teaches all limitation of claim 1 as stated above. Modified Wu does not explicitly teach a limitation wherein a compacted density of the positive electrode active material under 3 tons is 2.0 g/cm3 or more.
H. Wu teaches that the packing density of a cathode active material precursor may be from about 0.5 g/cm³ to about 4.0 g/cm³ ([0079, 0100]). However, H. Wu does not expressly teach the claimed compacted density of the resulting positive electrode active material under 3 tons.
However, C. Xu teaches a lithium manganese iron phosphate-based positive electrode material and expressly recognizes compaction density as a property of the material (page 3, lines 20-32). C. Xu teaches that controlling the particle size of the primary and secondary particles improves particle agglomeration and increases the compaction density of the material (page 5, lines 33-42) and thereby increasing the standby time of the battery (page 1, lines 57-59; page 2, lines 1-2). C. Xu further teaches optimizing particle size and cohesion to improve the compaction density of the material (page 3, lines 20-32), and teaches a preferred compaction density of 2.0-2.68 g/cm³, more preferably 2.2-2.55 g/cm³ (page 3, lines 39-43). C. Xu further provides a method for determining compaction density by pressing a sample at 2 MPa and calculating the density based on the measured thickness and volume (page 8, lines 20-25). Thus, C. Xu expressly recognizes compaction density as a result-effective variable and also teaches values overlapping the claimed range. It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Moreover, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to optimize the particle size and cohesion of the modified Wu material so as to obtain a compacted density of 2.0 g/cm³ or more, because C. Xu expressly teaches that optimization of particle size and cohesion improves compaction density and that increased compaction density is advantageous for improving the volumetric energy density of the lithium battery and ensuring electrode density (page 3, lines 29-43). Discovering the optimum or workable ranges of a result-effective variable involves only routine skill in the art. See MPEP 2144.05(II). Therefore, when subjected to the same pressure conditions of 3 tons as instantly claimed (which is a product-by-process limitation), the resultant active material of modified Wu would also be expected to exhibit the compacted density of 2.0 g/cm³ or more.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lili Rassouli whose telephone number is (571)272-9760. The examiner can normally be reached Monday-Thursday 8:00 AM-4:00 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matthew T Martin can be reached at (571) 270-7871. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/LILI RASSOULI/ Examiner, Art Unit 1728
/JESSIE WALLS-MURRAY/ Primary Examiner, Art Unit 1728
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