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 08/07/26, have been fully considered. Claim(s) 1, 7, and 8 is/are amended; claim(s) 2, 5, 6, 9, and 10 stand(s) as originally or previously presented; and claim(s) 3 and 4 is/are canceled; no new matter has been added. Examiner affirms that the original disclosure provides adequate support for the amendment.
Upon considering said amendment and arguments, the previous specification objection as well as 35 U.S.C. 103 rejection have been withdrawn. Applicant’s amendment necessitated the new grounds of rejection below.
Claim Rejections - 35 USC § 112
The text forming the basis for the rejection under 35 U.S.C. 112(b) may be found in a prior Office Action.
Claims 1, 2, and 5–10 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.
Claim 1 recites “the lithium composite oxide is secondary particles in which a plurality of primary particles are agglomerated, wherein the primary particle is a core-shell particle” (lines 3–5). There is insufficient antecedent basis for “the primary particle” due to the previous recitation of “primary particles”, making it unclear which primary particle “the primary particle” references.
The specification’s p. 4, lines 3 and 4, describe that the lithium composite oxide may be a secondary particle in which a plurality of primary particles are agglomerated, further describing that the Ti content satisfying instant Eq. 1 may be calculated for one of the primary particles (lines 4–20). Additionally, p. 5, lines 22–24 appear to reference the same primary particle in describing that such may be a core-shell particle, though this description is only of one embodiment and, thus, non-limiting to the claimed primary particle. Thus, for this Office Action claim 1 will be interpreted to require “the lithium composite oxide is secondary particles in which a plurality of primary particles are agglomerated, wherein at least one of the primary particles is a core-shell particle”, which appears consistent with pp. 4 and 5.
The dependent claims fail to correct this deficiency and are rejected likewise. Appropriate correction is required.
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) 1, 2, and 5–10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Toyama et al. (WO 2020195790 A1; citations to English equivalent US 20220115656 A1) in view of Nakagawa et al. (US 20090239146 A1) and Kim et al. (US 20120156565 A1).
Regarding claim 1, Toyama discloses a positive electrode active material comprising a lithium composite oxide containing at least nickel and titanium (e.g., Abstract and Ex. 5 in Table 1), wherein the lithium composite oxide is secondary particles in which a plurality of primary particles are agglomerated (Abstract), wherein the primary particle is a core-shell particle comprising a core (base lithium metal oxide particles, e.g., Abstract, fig. 3, and Ex. 5, ¶ 0140 and 0145) and a shell present on at least a portion of a surface of the core (see concentrated surface layer of X element (i.e., Ti in Ex. 5 (Table 1), ¶ 0053).
Per ¶ 0043, the X element/Ti—sourced from titanium oxide (¶ 0140)—reacts with Li to form the shell, and, thus, Toyama discloses a lithiated Ti compound in the shell. However, Toyama fails to explicitly disclose that at least titanium oxide is present in the shell.
It would be reasonable, though, to expect such in the shell as an unreacted raw material. For example, Nakagawa teaches an analogous lithium metal oxide positive active material (Abstract) with a Ti-containing oxide adhered to the surface (¶ 0014). Similar to Toyama (¶ 0140, 0145), Nakagawa dry-mixes titanium oxide with the active material, followed by high-temperature heating (¶ 0056), which is understood to form a coating including a lithium titanium oxide such as Li2TiO3 as well as unreacted source TiO2 (¶ 0057).
Given the similarity in methods, it would have been readily envisaged by and/or obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to expect or include a non-zero quantity of unreacted titanium oxide in Toyama’s shell, as demonstrated by Nakagawa, and reasonably expect to maintain a successful Ti coating on the lithium composite oxide.
Assuming, arguendo, that the above were insufficient to render obvious titanium oxide in the shell, Nakagawa teaches that the Ti oxide to be adhered may include Li2TiO3, Li4Ti5O12, TiO2, and mixtures thereof (¶ 0029). Ultimately, Nakagawa’s coating reduces reaction resistance from Li+ (de)intercalation to improve input/output power (¶ 0028).
As Toyama recognizes a lithiated titanium compound in the shell, while Nakagawa recognizes TiO2, LTO compounds like Li2TiO3 and Li4Ti5O12, and mixtures thereof as equivalent Ti-based coatings for positive active material, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to incorporate a mixture of titanium oxide alongside a lithiated Ti compound such as Li2TiO3 with the reasonable expectation of reducing reaction resistance from Li+ (de)intercalation and improving input/output power, as taught by Nakagawa.
Further, Kim teaches a lithium metal oxide positive active material coated with a complex layer of TiO2 and LiTixOy, 1 ≤ x ≤ 2, and 2.5 ≤ y ≤ 3 (¶ 0013). Kim teaches that the coating secures structural stability while affording the material excellent thermal stability and (dis)charge capacity (¶ 0026).
As Toyama similarly desires the shell to stabilize the crystal structure in the vicinity of the primary particles’ surfaces during (dis)charge (¶ 0039, 0040), it would have been further obvious to employ a joint TiO2-Li2TiO3 shell with the reasonable expectation of securing structural stability while achieving excellent thermal stability and (dis)charge capacity, as taught by Kim.
Toyama further discloses a Ti-based surface layer atop each primary particle (see D1, which represents the surface vicinity of each primary particle, in figs. 3–6; see also ¶ 0043, where X element is preferably Ti). As D1 is 1 nm from the surface and the primary particles’ average diameter is at least 50 nm (¶ 0048), such would correlate with the instant a1 and a2 as the “shell” (as 1 nm/50 nm = 0.02r). Similarly, the Ti is also inside the primary particle’s central part as D2 (e.g., ¶ 0052), which is ≥ 0.2r from the surface (¶ 0163) and, thus, correlates with the instant b1 as the “core”. Toyama discloses that D1 and D2 are average values calculated via EDX line analysis (¶ 0162, 0164, figs. 3–6) in a manner appearing substantially similar to the instant disclosure’s EDX analysis (e.g., figs. 1–9), where D1 is, e.g., 1.87x D2 (based on D1 of 2.8 and D2 of 1.5 in Ex. 5, ¶ 0165 and fig. 5).
Although Toyama fails to explicitly disclose the 1.87x Ti relation as an average Ti value based on the instant (a1+a2)/2—as well as the explicit 0–0.05r (a1), 0.05–0.95r (b1), and 0.95r to r (a2) regions based on the primary particle’s short-axis diameter from the TEM/EDX, with the region of 0 to 0.05r and the region of 0.95r to r from the start point of the line sum spectrum corresponding to the shell and the region of 0.05r to 0.95r from the start point of the line spectrum corresponding to the core—and, thus, a value explicitly falling within the recited 1.4≤{(a1+a2)/2}/b1≤2.502, Toyama’s 1.87x, in being measured with a technique and at distances substantially similar to the instant disclosure, appears to correlate with, encompass, or at least approach the instant range, absent evidence otherwise. Specifically, as noted above, because D1 is 1 nm from the surface and the primary particles’ average diameter is at least 50 nm (¶ 0048), such would mean that the region of 0 to 0.05r and the region of 0.95r to r from the start point of the line sum spectrum would correspond to the shell. Likewise, because the Ti is also inside the primary particle’s central part as D2, which is ≥ 0.2r from the surface, such would mean that the region of 0.05r to 0.95r from the start point of the line sum spectrum would correspond to the core.
Again, although Toyama may fail to explicitly disclose a value falling within Equation 1, it would have been obvious to routinely select within the apparent overlap/encompassing range with a reasonable expectation of employing a successful, Ti-coated lithium complex oxide (MPEP 2144.05 (I)).
Assuming, arguendo, that such failed to render obvious instant Eq. 1 by Toyama’s not disclosing D1 as an average content, Examiner provides linear-interpolation calculations below (assuming linear decrease) from Toyama’s D0, D1, and D2 from Ex. 5 (Table 1), which appear to account for the “average” content—and, thus, correspond to a1 or a2—in Toyama’s concentrated region within 3 nm from surface (where D2 is then taken as corresponding to b1 as being in the core, and at% would necessarily yield the same ratio as mol% because mol% is merely scaled by Avogadro’s number):
PNG
media_image1.png
159
583
media_image1.png
Greyscale
Accordingly, even if this ~ 2.6 narrowly fails to encompass or overlap the recited 1.4–2.502, a prima facie case of obviousness exists where the claimed ranges and prior art ranges fail to overlap but are close enough that one skilled in the art would have expected them to have the same properties (see MPEP 2144.05 (I)). Because Toyama discloses the recited material, whose Ti concentration is measured substantially similarly to the instant disclosure, along with a substantially similar preparation method and mixing ratios (mixing lithium precursor, Ni/Co/Mn precursors, and TiO2, followed by multiple heating and calcination treatments) as the instant specification (e.g., p. 25, lines 14–25), the skilled artisan would have reasonably expected the disclosed and recited materials to exhibit the same properties (MPEP 2112.01 (I)).
More specifically, Toyama only includes comparative examples with, at most, D1 and D2 and, thus, appears to omit a “true” comparative example demonstrating poorer performance from a set of values (i.e., D0, D1, and D2) allowing the instant Eq. 1 to be approximated. Further, it is unclear that Eq. 1 is critical based on instant Table 2 based on factors already explained (see, e.g., O.A. dated 05/11/26). Thus, absent demonstrated criticality, the recited 1.4–2.502 appears obvious over Toyama.
More importantly, however, Toyama generally discloses that D0 > D1 but preferably < 10x D1 (¶ 0058), and D1 is preferably 1.5–20x D2 (¶ 0056). When D0 > D1, the primary particle’s surface is physically protected to prevent crystal-structure deterioration from electrolyte permeation, yielding favorable (dis)charge characteristics, and when D0 < 10x D1, there is no increased resistance due to a layer containing the X element at the primary-particle interface, making it possible to obtain favorable rate characteristics (¶ 0058). Further, when D1 is 1.5x or more, the X element such as Ti is sufficiently concentrated in the vicinity of the surface to stabilize the material’s crystal structure, which improves cycle characteristics (¶ 0056). When the ratio is too large, large concentration differences exist between the vicinity of the surface and the central part of the primary particle, yielding uneven Li+ (de)intercalation and a concern that discharge capacity may diminish or that rate characteristics may deteriorate (¶ 0056).
To balance all these effects, then, the skilled artisan would have readily envisaged controlling the Ti contents throughout the gradient, so it would have been obvious to arrive at the recited range by routinely optimizing the Ti content within each of D0, D1, and D2 (i.e., at surface and within core) and, thus, necessarily controlling each of a1, a2, and b1’s average values and, by extension, the ratio {(a1+a2)/2}/b1 (MPEP 2144.05 (II)).
Regarding the limitations the 1) “average of the average content (mol%) of titanium measured based on all metal elements excluding lithium in the region of 0 to 0.05r from the start point of the line sum spectrum and the average content (mol%) of titanium measured based on all metal elements excluding lithium in the region of 0.95r to r is more than 0.227 mol% and less than 2.699 mol%”, and 2) “wherein the average content (mol%) of titanium measured based on all metal elements excluding lithium in the region of 0.05r to 0.95r from the start point of the line sum spectrum is greater than 0.083 mol% and less than 0.832 mol%”, such represent (a1+a2)/2 and b1, respectively (per claim 1’s definitions of a1, a2, and b1). According to the above rationale, then, based on Toyama’s broader disclosure of D0 > D1 > D2—and the notion that the skilled artisan would have readily understood to control the Ti content at each portion of the gradient—it would have been obvious to arrive at the respectively recited ranges of (a1+a2)/2 and b1 by routinely optimizing the surface and core Ti contents (MPEP 2144.05 (II)).
Regarding claim 2, modified Toyama discloses the positive electrode active material of claim 1, wherein titanium in the lithium composite oxide is present in an amount in an amount of 2 mol% based on all metal elements excluding lithium (Toyama’s Ex. 5, Table 1), falling within greater than 0.2 mol% and less than 3.3 mol%.
Regarding claim 5, modified Toyama discloses the positive electrode active material of claim 1, wherein the lithium composite oxide further comprises Co and Mn (Toyama’s Ex. 5, Table 1).
Regarding claim 6, modified Toyama discloses the positive electrode active material of claim 1.
Toyama further exemplarily discloses a Li:Ni:Co:Mn:Ti ratio of 1.02:0.90:0.03:0.05:0.02 (Ex. 5, Table 1) but, in failing to explicitly articulate the O content, fails to explicitly disclose the recited
Chemical Formula 1.
More generally, though, Toyama discloses a formula of Li1+aNibCocMdXeO2+α, where, based on Ex. 5, M is Mn, and X is Ti (¶ 0027). Further, a is preferably -0.02–0.02 because this range suppresses cation mixing to obtain high discharge capacity (¶ 0033, 0034); b is 0.85–0.95 because this range increases discharge capacity while reducing crystal-structure distortion (¶ 0037); c is 0–0.2 because this range stabilizes the crystal structure without reducing costs (¶ 0038); d is 0–0.2 because this range provides favorable rate characteristics without decreasing discharge capacity (¶ 0041); e is 0–0.08 because this range stabilizes the crystal structure in the surface’s vicinity without reducing discharge capacity (¶ 0044); and α is greater than -0.2 and less than 0.2 because this range provides high discharge capacity alongside an appropriate crystal structure (¶ 0046). To balance all these effects, then, it would have been obvious to arrive at the recited formula by routinely optimizing the molar ratios in the lithium composite oxide’s composition (MPEP 2144.05 (II)).
Regarding claims 7 and 8, modified Toyama discloses the positive electrode active material of claim 1, wherein the shell further comprises a metal oxide represented by instant Chemical Formula 2, where a = 1, b = 2, c = 0, d = 3, and M3 is absent because c = 0, wherein the shell further comprises lithium titanium oxide (e.g., LiTi2O3 from Nakagawa/Kim above)
Regarding claims 9 and 10, modified Toyama discloses a lithium secondary battery using a positive electrode comprising the positive electrode active material according to claim 8 (Toyama, e.g., Abstract, ¶ 0118 and Ex. 5).
Response to Arguments
Applicant’s arguments with respect to claim(s) 1 have been considered. Applicant’s amendment overcame the previous 35 U.S.C. 103 rejection—which, as noted above, has been withdrawn—and necessitated the new grounds of rejection citing the new reference(s) Nakagawa and Kim, as established above. Examiner respectfully disagrees with Applicant’s remaining arguments against Toyama as follows:
Applicant argues that Toyama only uses TiO2 as a synthetic precursor but does not disclose residual TiO2 in the shell. Examiner respectfully submits that Nakagawa and Kim cure this deficiency for the above reasons.
Applicant further appears to argue that Toyama’s concentrated layer is not a shell on the primary particle’s surface and, thus, cannot be used to calculate Eq. 1. Specifically, Applicant asserts that Toyama’s concentrated layer is “several nanometers deep from the primary particle surface” (¶ 0068).
Examiner respectfully disagrees that Toyama’s layer is not on the primary particle’s surface because Toyama plainly discloses that the layer forms on the primary particle’s surface at least in ¶ 0039, 0043, 0052, and 0053 (as well as Ex. 5, ¶ 0165). Toyama’s disclosing that the layer is several nm deep from the surface appears to just reference the coating layer’s depth/dimension, meaning the layer would still start at the surface but penetrate up to several nm (as in Toyama’s ¶ 0165, where the Ti is concentrated up to a depth of 2 nm from the primary particle’s interface/surface). Additionally, even if the above were untrue, Applicant is yet to rebut Toyama’s recognition of D0 at the primary particle’s interface/surface, which is even more Ti-concentrated (see, e.g., ¶ 0058 and 0165) and, thus, is considered part of the shell, which is further consistent with above linear-interpolation calculations as well as optimization rationale. Thus, because Toyama’s Ti concentrations correlating with a1 and a2 still appear based on the Ti concentration in the shell, this argument is unpersuasive.
Applicant further argues against Nakamura, though such arguments are moot because this reference is no longer used.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN S MEDLEY whose telephone number is (703)756-4600. The examiner can normally be reached 8:00–5:00 EST M–Th and 8:00–12:00 EST F.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jonathan Leong, can be reached on 571-270-192. 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.
/J.S.M./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 9/28/2026
