DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This is a final office action in response to Applicant’s remarks and amendments filed on September 18, 2025. Claims 1, 7, 8, 10 and 14 are currently amended. Claims 1, 3-14, 16 and 17 are pending review in this action.
New grounds of rejection necessitated by Applicant’s amendments are presented below.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 3, 5-8, 10, 12, 14, 16 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Pre-Grant Publication No. 2014/0295287, hereinafter Eisele in view of Solid State Ionics 206, pp 28-32, hereinafter Rangasamy and with evidence from Solid State Ionics 183, pp 48-53, hereinafter Shimonishi.
Regarding claim 1, Eisele teaches a lithium-ion conducting compound having a garnet-like crystal structure (abstract). The compound has the general formula Lin[A(3-a’-a’’)A’(a’)A’’(a’’)][B(2-b’-b’’)B’(b’)B’’(b’’)][C’(c’)C’’(c’’)]O12 (abstract and paragraph [0003]).
This formula corresponds to the instantly claimed formula (I) with z = 0 and δ = 0.
With respect to elements, Eisele’s formula corresponds to instantly claimed formula (I) as follows:
A is lanthanum (La) plus a trivalent M3+, which may be yttrium (Y), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm) or ytterbium (Yb) (paragraph [0030]). Thus, it is understood that the lanthanum site is doped with at least one trivalent ion selected from the above group. The ionic radius of each of the above ions is smaller than that of La3+.
A’ is the divalent M2+ and may be Ca, Sr or Ba (paragraph [0006]);
A’’ is the monovalent M1+ and may be Na or K (paragraph [0007]);
B is Zr (paragraph [0009]);
B’ is the pentavalent M5+ and may be Ta, Nb, Sb or Bi (paragraph [0010]);
B’’ is the hexavalent M6+ and may be Te, W or Mo (paragraph [0011]);
C’ is aluminum (Al) (paragraph [0013]).
Given the above, Eisele’s compound is an aluminum-doped lithium lanthanum zirconate (LLZO).
With respect to content Eisele’s formula corresponds to the instantly claimed formula (I) as follows:
a’ corresponds to y’ and satisfies 0≤a’<2 (paragraph [0007]);
a’’ corresponds to y’’ and satisfies 0≤a’<1 (paragraph [0007]);
b’ corresponds to z’ and satisfies 0≤b’≤2 (paragraph [0011]);
b’’ corresponds to z’’ and satisfies 0≤b’’≤2 (paragraph [0011]);
c’ corresponds to x and satisfies 0≤c’≤0.5 (paragraph [0014]);
c’’ and C’’ do not have analogs in instant formula (I), but Eisele allows for c’’ to be zero (paragraph [0014]).
The content of A, which corresponds to La plus M3+, is given as 3-a’-a’’, which is equivalent to the instantly claimed 3-y’-y’’, which is the combined content of La plus M3+.
M3+ is present, therefore its content (corresponding to the instant y) is less than 3.
The content of B, which is Zr, is given as 2-b’-b’’, which is equivalent to the instantly claimed 2-z-z’-z’’, with z = 0.
The content of Li is given as n = 7+a’+2a’’-b’-2b’’-3c’-4c’’. With c’’ = 0, this corresponds to the instantly claimed content for Li with the only difference that u would be zero.
However, the Li content in Eisele is a computed, rather than experimentally determined value and is based on the expected stoichiometry of the garnet. Thus, the actual amount of lithium in the compound is not reported by Eisele.
Eisele provides 10% excess lithium during formation of the compound for the purpose of compensating for lithium loss during sintering (paragraph [0063]). Eisele further teaches a sintering temperature in the range 900 °C to 1250 °C (paragraph [0060]).
Eisele does not: 1) explicitly teach Y and one other trivalent cation; 2) explicitly teach a value of u greater than 0.01 for a superstoichiometric lithium content; and 3) report on the crystal structure of the compound.
Regarding 1), it would have been obvious to the ordinarily skilled artist to select Y and one other trivalent cation out of Eisele’s finite list of cations without undue experimentation and with a reasonable expectation of success.
Regarding 2), it is known in the art that the amount of lost lithium during sintering while forming LLZO is a function of temperature – see, Shimonishi who starts with 10% excess lithium and shows that at 800°C there is effectively no loss relative to the precursor composition, while at 1180°C there is substantial loss (Experimental Section, 1st paragraph and Table 1). Meanwhile, Rangasamy teaches forming an Al-doped LLZO by sintering at 1000 °C – a temperature within the range taught by Eisele. Rangasamy includes 0.24 mol Al per formula unit, which means that based on stoichiometry (Li7-3x,AlxLa3Zr2O12) Li is expected to be present at 6.28 mol per formula unit. Rangasamy varies the amount of Li in the precursor and shows that starting with no excess lithium (7 mol) results in just barely sub-stoichiometric lithium content (6.24 mol Li vs the expected 6.28) and starting with approximately 14% excess lithium (8 mol) results in substantial superstoichiemetric content (7.32 mol Li vs the expected 6.28 or a “u” value of 1.04) (Figure 2).
It is further noted that applicant contends that the presence of both the aluminum dopant and the trivalent ion at the lanthanum site permit for the inclusion of superstoichiometric lithium within the compound (see instant specification, p.15, lines 17-31; p.16, lines 1-6; p. 17, lines 10-16; p.18, lines 6-10).
Thus, absent evidence to the contrary, the ordinarily skilled artist who would follow Eisele’s direction of including 10% excess lithium and sintering at 1000 °C would be expected to produce a compound with superstoichiometric lithium and a value for u greater than 0.01.
Regarding 3), it is well-known in the art that the cubic phase of LLZO is the preferred crystal structure due to its superior ionic conductivity and the Al-doping is done for the purpose of stabilizing the cubic phase – see, e.g. Rangasamy (Introduction, 1st paragraph and Conclusion, 1st paragraph).
Rangasamy further shows that increasing the amount of Li past the stoichiometric point eventually leads to a transformation from the cubic to the tetragonal phase (Conclusion, 2nd paragraph). Under the specific conditions of 0.24 mol Al per formula unit and sintering at 1000°C, Rangasamy shows that a pure cubic phase exists at 6.24 mol Li per formula unit (stoichiometric value is 6.28) and the tetragonal phase is present at 7.32 mol Li per formula unit (figure 2). Rangasamy speculates that the transition point is somewhere below 7 mol Li per formula unit. It is thus expected that at least over the continuum from 6.28 mol Li per formula unit to 7 mol Li per formula unit, there is a point where the cubic phase is equal to or exceeds 90.1%.
Given that Eisele already teaches the doping at the La site and given that Eisele’s compound is expected to have superstoichiometric Li content and given Rangasamy’s clear articulation of the effect of Li on the cubic phase and the desire to maintain the cubic phase, it would have been obvious to the ordinarily skilled artist before the effective filing date of the claimed invention to optimize the amount of Li which would achieve near pure cubic phase (> 90%) for the process conditions taught by Eisele for the purpose of achieving optimal ionic conductivity of the compound.
Eisele's optimum ranges for the instantly claimed x, y, y’, y’’, z’, z’’ and y’+y’’ overlap the instant application's optimum ranges. 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.
Regarding claim 3, Eisele teaches that c’ (corresponding to the instant x) satisfies 0≤c’≤0.5 (paragraph [0014]).
Eisele's optimum range for the instantly claimed x overlaps the instant application's optimum 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.
Regarding claim 4,
Therefore the range for Y taught by Eisele overlaps the instantly claimed up to 0.2 mol.
Eisele's optimum range overlaps the instant application's optimum range of up to 0.2 mol per formula unit. 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.
Regarding claim 5, Eisele teaches that there is a trivalent ion M3+ doped on the lanthanum site. Therefore, instantly claimed y (the content of M3+) is not zero.
The numerator of the claimed ratio is (3-y-y’-y’’+y+y’+y’’), which is always 3, regardless of the values of y, y’ and y’’.
The denominator of the claimed ratio is (2-z-z’-z’’+z’’+z’+z+y), which is always 2+y, regardless of the values of z, z’ and z’’.
Thus, the claimed ratio reduces to 3/(2+y).
Given that Eisele teaches that y is not zero, the claimed ratio is less than 1.5.
Eisele's optimum range overlaps the instant application's optimum range of greater than 1 and less than 1.5. 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.
Regarding claim 6, Eisele teaches that there is a trivalent ion M3+ doped on the lanthanum site. Therefore, instantly claimed y (the content of M3+) is not zero.
The numerator of the claimed ratio is (3-y-y’-y’’+y+y’+y’’), which is always 3, regardless of the values of y, y’ and y’’.
The denominator of the claimed ratio is (2-z-z’-z’’+z’’+z’+z+y), which is always 2+y, regardless of the values of z, z’ and z’’.
Thus, the claimed ratio reduces to 3/(2+y).
Given that Eisele teaches that y is not zero, the claimed ratio is less than 1.5.
Eisele's optimum range for the ratio overlaps the instant application's optimum range of 1.0 to 1.49. 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.
Regarding claim 7, Eisele teaches that the trivalent ion may be praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm) or ytterbium (Yb) (paragraph [0030]).
Regarding claim 8, Eisele teaches gadolinium (Gd) (paragraph [0030]). Lanthanum and its dopants together account for up to 3 mol per formula unit (paragraphs [0003, 0030]).
Therefore the range for gadolinium taught by Eisele overlaps the instantly claimed at least 0.1 mol.
Eisele's optimum range overlaps the instant application's optimum range of at least 0.1 mol per formula unit. 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.
Regarding claim 10, Eisele teaches the instantly taught not polyvalent ions (paragraph [0030]).
Regarding claim 12, it is well-known in the art that the cubic phase of LLZO is the preferred crystal structure due to its superior ionic conductivity and the Al-doping is done for the purpose of stabilizing the cubic phase – see, e.g. Rangasamy (Introduction, 1st paragraph and Conclusion, 1st paragraph).
Rangasamy further shows that increasing the amount of Li past the stoichiometric point eventually leads to a transformation from the cubic to the tetragonal phase (Conclusion, 2nd paragraph). Under the specific conditions of 0.24 mol Al per formula unit and sintering at 1000°C, Rangasamy shows that a pure cubic phase exists at 6.24 mol Li per formula unit (stoichiometric value is 6.28) and the tetragonal phase is present at 7.32 mol Li per formula unit (figure 2). Rangasamy speculates that the transition point is somewhere below 7 mol Li per formula unit. It is thus expected that at least over the continuum from 6.28 mol Li per formula unit to 7 mol Li per formula unit, there is a point where the cubic phase is equal to or exceeds 95%.
Given that Eisele already teaches the doping at the La site and given that Eisele’s compound is expected to have superstoichiometric Li content and given Rangasamy’s clear articulation of the effect of Li on the cubic phase and the desire to maintain the cubic phase, it would have been obvious to the ordinarily skilled artist before the effective filing date of the claimed invention to optimize the amount of Li which would achieve near pure cubic phase (> 95%) for the process conditions taught by Eisele for the purpose of achieving optimal ionic conductivity of the compound.
Regarding claim 14, Eisele teaches that the compound is sintered (paragraph [0060]) and reports ionic conductivities of multiple Al-doped LLZO compounds of greater than 10-5 S/cm (Table 1). Given this and that Eisele teaches substantially the same class of compounds as instantly claimed, the ionic conductivities of the class of compounds are expected to be greater than 10-5 S/cm.
Regarding claim 16, Eisele teaches that:
b’’ (corresponding to the content of M6+) may be zero (paragraph [0011]);
b’ (corresponding to the content of M5+) may be zero (paragraph [0011]);
a’ (corresponding to the content of M2+) may be zero (paragraph [0007]);
a’’ (corresponding to the content of M1+) may be zero (paragraph [0007]).
Eisele further does not teach a tetravalent dopant (M4+), therefore Eisele teaches that the content of M4+ is zero.
Regarding claim 17, it is well-known in the art that the cubic phase of LLZO is the preferred crystal structure due to its superior ionic conductivity and the Al-doping is done for the purpose of stabilizing the cubic phase – see, e.g. Rangasamy (Introduction, 1st paragraph and Conclusion, 1st paragraph).
Rangasamy further shows that increasing the amount of Li past the stoichiometric point eventually leads to a transformation from the cubic to the tetragonal phase (Conclusion, 2nd paragraph). Under the specific conditions of 0.24 mol Al per formula unit and sintering at 1000°C, Rangasamy shows that a pure cubic phase exists at 6.24 mol Li per formula unit (stoichiometric value is 6.28) and the tetragonal phase is present at 7.32 mol Li per formula unit (figure 2). Rangasamy speculates that the transition point is somewhere below 7 mol Li per formula unit. It is thus expected that at least over the continuum from 6.28 mol Li per formula unit to 7 mol Li per formula unit, there is a point where the cubic phase is equal to or exceeds 98%.
Given that Eisele already teaches the doping at the La site and given that Eisele’s compound is expected to have superstoichiometric Li content and given Rangasamy’s clear articulation of the effect of Li on the cubic phase and the desire to maintain the cubic phase, it would have been obvious to the ordinarily skilled artist before the effective filing date of the claimed invention to optimize the amount of Li which would achieve near pure cubic phase (> 98%) for the process conditions taught by Eisele for the purpose of achieving optimal ionic conductivity of the compound.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over U.S. Pre-Grant Publication No. 2014/0295287, hereinafter Eisele and Solid State Ionics 206, pp 28-32, hereinafter Rangasamy as applied to claim 1 above, and further in view of U.S. Pre-Grant Publication No. 2016/0329598, hereinafter Schneider.
Regarding claim 11, Eisele teaches an aluminum-doped LLZO garnet as a solid electrolyte for a battery.
Eisele fails to teach an amorphous phase.
Schneider teaches a closely related aluminum-doped LLZO garnet as a solid electrolyte for a battery (paragraphs [0024, 0035]). Schneider teaches a melting method for forming the compound, which is an improvement over Eisele’s standard method, because it simplifies the process and further results in the formation of an amorphous phase which improves the conductivity of the compound (abstract, paragraphs [0021, 0039]).
Therefore it would have been obvious to the ordinarily skilled artist before the effective filing date of the claimed invention to implement Schneider’s method to form Eisele’s compound for the purpose of simplifying the process and forming the amorphous phase, which improves the conductivity of the compound.
Although Schneider does not report the composition of the amorphous phase, it is understood to be as instantly claimed, given that the instant specification specifically points to Schneider as describing the instantly used method (p. 13, lines 26-31 and p. 14, lines 1-3).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over U.S. Pre-Grant Publication No. 2014/0295287, hereinafter Eisele and Solid State Ionics 206, pp 28-32, hereinafter Rangasamy as applied to claim 1 above, and further in view of U.S. Pre-Grant Publication No. 2016/0308244, hereinafter Badding.
Regarding claim 13, Eisele teaches a lithium-ion conducting compound for a solid electrolyte of a battery (paragraph [0047]).
Eisele does not specify a particle size.
Badding teaches a lithium ion conductor in powder form and used to form a solid electrolyte membrane for a battery (paragraphs [0103, 0143]). The lithium ion conductor is a doped LLZO (paragraph [0105]). Badding teaches that a desirable D50 particle size of the powder is in the range 0.1 µm to 10 µm (paragraph [0102]).
Therefore it would have been obvious to the ordinarily skilled artist before the effective filing date of the claimed invention to form Eisele’s lithium-ion conducting compound in the form of a powder with a particle size in the range 0.1 µm to 10 µm for the purpose of forming a solid electrolyte membrane for a battery.
Allowable Subject Matter
Claim 9 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Response to Arguments
Applicant’s newly added limitations have been considered. However, after further search and consideration, the previously presented combination of the Eisele and Rangasamy references was found to address the amended claims.
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 LILIA V NEDIALKOVA whose telephone number is (571)270-1538. The examiner can normally be reached 8.30 - 5.00 PM.
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, Miriam Stagg can be reached at 571-270-5256. 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.
/STEWART A FRASER/Primary Examiner, Art Unit 1724
LILIA V. NEDIALKOVA
Examiner
Art Unit 1724