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 12/22/2025 have been fully considered. Claim(s) 1, 11, 17 is/are amended; claim(s) 1-10 remain withdrawn. Claims 11-20 are pending review in this Office action. Examiner affirms that the original disclosure provides adequate support for the amendment.
Upon considering said amendment and arguments, the previous rejections under 35 U.S.C. 102 and 35 U.S.C. 103 set forth in the Office action mailed 09/30/2025 has/have been withdrawn. Applicant’s amendment necessitated the new grounds of rejection below.
Claim Rejections - 35 USC § 102
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 11, 12, and 15 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kang et al. KR101676405B1 (cited in IDS filed 08/14/2025; cited with machine translation and paragraphs [0093-0101] human translation, see 09/30/2025 Office action)
Regarding claims 11, 15, Kang discloses a negative electrode for an electrochemical cell that cycles lithium ions (Machine translation Kang [0001]), the negative electrode comprising:
an electroactive material particle exhibiting a core-shell structure defining a core and a shell surrounding the core ([0009]),
wherein the core comprises a lithiated SiO (i.e., silicon-based material) core (Human translation Kang [0093-0094]);
wherein the shell is a bi-layer structure including a first carbon coating layer (“primary carbon coating”) disposed on the core and a second carbon coating layer (“secondary carbon coating”) disposed on the first carbon coating layer over the core ([0009]) (claim 11).
Kang does not explicitly describe the first carbon coating layer as a discontinuous layer and the second carbon coating layer as a continuous layer. However, Kang performs Li alloying (i.e., lithium doping) with a core/first carbon coating precursor of the electroactive material particle ([0009]), this process indicated in paragraph [0048] of the instant specification as introducing discontinuities into the structure of the first carbon coating layer. As such, Kang’s first carbon coating layer is inherently a discontinuous layer (claim 11).
Kang’s second carbon coating prevents exposure of Li byproducts on the lithiated core/first carbon coating composite on the surface when forming a negative electrode slurry (Kang [0009-0010], [0029]). A skilled artisan would recognize that layer discontinuities would render Kang’s second carbon coating layer unsuitable by exposing Li byproducts on the core/first carbon coating; it follows that Kang’s second carbon coating layer is necessarily a continuous layer (claim 11).
Kang’s first carbon coating may be formed from a mixture of crystalline (i.e., graphitic) and amorphous carbon ([0037]), and second carbon coating is formed consisting essentially of amorphous carbon ([0012]) (claim 15).
While Kang does not explicitly disclose an electrical conductivity of the first or second carbon coating layer, inst. spec. [0076] indicates that the first carbon coating layer comprising a higher concentration of graphitic carbon exhibits higher electrical conductivity relative to the amorphous second carbon coating layer such that an electrical conductivity of Kang’s first amorphous/graphitic carbon coating layer is inherently greater than that of the amorphous second carbon coating layer as a material property of the layers (claim 11).
Regarding claim 12, Kang discloses the negative electrode of Claim 11. The silicon-based material of the core comprises a mixture of silicon (“semi-metal”), one or more silicon oxide compounds (“(semi)metal oxide”) ([0083]), one or more lithium silicide (“Li-Si compounds”) and one or more lithium silicate compounds ([0076]).
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 14, 16 are rejected under 35 U.S.C. 103 as being unpatentable over Kang et al. as applied to claim 11.
Regarding claims 14, 16, Kang discloses the negative electrode of claim 11. While Kang does not explicitly disclose the amount of lithium by weight in the electroactive material particle, Kang teaches mixing at least 2 parts Li metal powder to 98 parts by weight of the core and first carbon coating layer when lithiating the core material to increase the initial efficiency ([0076]), and mixing less than 30 parts Li metal to 70 parts by weight of the core and first layer to prevent excessive generation of reaction byproducts ([0076]) (claim 16).
As such, in balancing considerations of initial efficiency and byproduct generation, it would be obvious before the effective filing date of the instant application for one having ordinary skill in the art to optimize the amount of Li metal powder used to lithiate Kang’s negative electrode material; see MPEP 2144.05 II. In doing so, one would also optimize a weight of lithium in the electroactive material particle; while Kang does not disclose an exact weight, given that a weight percentage of lithium as a raw material ranges from 2-30 wt%, one having ordinary skill in the art could reasonably have utilized the similar claimed range of 5-15 wt% (claim 16).
Kang discloses that the electroactive material particle comprises 0.05-20 wt% first carbon coating layer ([0037]) and 1-15 wt% second carbon coating layer ([0035]), a total weight of the carbon of the two carbon coating layers equating to 1.05%-35 wt% and overlapping with a portion of the claimed range of carbon between 1.05-10 wt% in the electroactive material particle (MPEP 2144.05,I) (claim 16).
Furthermore, Kang discloses at least 0.05 wt% of first carbon coating layer is provided to control a reaction between Li metal powder and the silicon-based core during manufacture ([0037-0038]), and at least 1 wt% secondary carbon coating material is provided to prevent side reactions with an aqueous binder ([0035]). Additionally, unlike the silicon-based core material ([0083]), Kang does not indicate the carbon coatings contribute significantly to lithium storage, such that a skilled artisan would avoid excessive amounts of the carbon coatings in the interest of maximizing energy density (claim 16).
Thus, in seeking to balance providing sufficient protection with the first/second carbon coatings while maximizing energy density, it would be obvious for one having ordinary skill in the art to optimize the total coating weight between 1.05%-35 wt%, this range approximately encompassing the claimed range of 1-10%; see MPEP 2144.05 II (claim 16).
Kang also provides an example embodiment with a 40 nm thick first carbon coating layer which comprises 5.3% by weight of the core (Human translation Kang [0093]), which falls within the claimed range of 5 to 300 nm (claim 14).
Kang fails to explicitly disclose a second carbon coating layer having a thickness of 1 nm to 50 nn. However, as the total weight of each carbon coating corresponds to the density and thickness of the coating, a skilled artisan optimizing a weight of the second carbon coating material within a range of 1-15 wt% to balance protection ability and energy density ([0035], [0083]) would reasonably consider varying the thickness to achieve a different coating weight. Given that a 40nm thick first carbon coating layer is about 5 wt% of Kang’s example of the electroactive material particle (Human translation Kang [0093]), a skilled artisan performing this optimization between 1-15 wt% would reasonably use a range of second carbon coating layer thickness overlapping with at least a portion of the claimed range of 1-50 nm (MPEP 2144.05 II) (claim 14).
Kang does not explicitly indicate a thickness of the second coating layer as being less than the first coating layer. However, a skilled artisan would need to select at least some relation of the second coating layer thickness relative to the first coating layer, with the only possible configurations being a second coating layer thickness less than, equal to, or greater than the first coating layer.
It would therefore have been obvious for one of ordinary skill in the art to routinely explore the selection of a second coating layer thickness less than the first coating layer thickness from the finite number of possible thickness configurations with a reasonable expectation of successfully forming the carbon coating layers (claim 14) (MPEP 2143 I. E).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Kang as applied to claim 12, further in view of Luo et al. WO2021136245A1 (Cited in IDS filed 08/14/2025, U.S. publication US20230034396A1 cited as an English equivalent)
Regarding claim 13, Kang discloses the negative electrode of Claim 12. While Kang discloses that the lithiated silicon-based material may further comprise an additional metal besides SiO ([0043]), and discloses a desirability to prevent leaching of lithium materials into an active material slurry causing an increase in pH ([0006]), Kang does not explicitly select potassium (K), magnesium (Mg), sodium (Na), or calcium (Ca) as an additional metal, or indicate the element constitutes 5-20 wt% of the electroactive material particle to address this consideration.
Luo, directed to a similar electroactive material particle with an analogous lithiated silicon-based core coated with a carbon film (Luo [0025], [0030]), teaches the inclusion of metal such as Mg or Ca inter alia in the core to further protect the lithiated silicon-based core when forming a slurry of the electroactive material particle ([0039]). A weight content of this metal is optimized within a range of 0.1-20 wt% to protect the core without adversely impacting the electroactive material capacity ([0055]).
As such, in seeking to further protect the electroactive material particle, it would be obvious for one of ordinary skill in the art to provide Kang’s silicon-based material of the core with Mg or Ca as taught by Luo, where Mg or Ca are selected from Luo’s finite list of suitable metals as a predictable solution (MPEP 2143 I. E). Such a modification would be made with a reasonable expectation of success because Kang and Luo are directed to a similar structure of a lithiated silicon-based core coated with a carbon coating layer, and seek similar beneficial effects of protecting the lithiated silicon-based core.
In seeking to provide this beneficial effect without adversely impacting the electroactive material capacity, it would further be obvious to optimize a weight content of the Mg or Ca between 0.1-20 wt% according to Luo’s teaching, encompassing the claimed range (5-20 wt%, claim 13) such that a skilled artisan would have selected within the encompassed range through routine optimization with a reasonable expectation of success (MPEP 2144.05 II).
Claims 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over Kang.
Regarding claim 17 and 18, Kang discloses a negative electrode for an electrochemical cell that cycles lithium ions ([0001]), the negative electrode comprising:
a mixture of electroactive material particles (“electrode active material”), electrically conductive particles (“carbon black”, [0101]), and a polymer binder ([0046-0047]),
wherein each of the electroactive material particles exhibits a core-shell structure defining a core and a shell surrounding the core ([0009]) (claim 17).
The silicon-based material of the core comprises a mixture of silicon (“semi-metal”), one or more silicon oxide compounds (“(semi)metal oxide”) ([0083]), one or more lithium silicide (“Li-Si compounds”) and one or more lithium silicate compounds ([0076]) (claim 17).
The shell is a bi-layer structure including a first carbon coating layer (“primary carbon coating”) disposed on the core and a second carbon coating layer (“secondary carbon coating”) disposed on the first carbon coating layer over the core ([0009]) (claim 17).
Kang does not explicitly describe the first carbon coating layer as a discontinuous layer and the second carbon coating layers as continuous layers that completely encapsulate the first carbon coating layer and the core on which it is disposed. However, Kang performs Li alloying (i.e., lithium doping) with a core/first carbon coating precursor of the electroactive material particle ([0009]), this process indicated in paragraph [0048] of the instant specification as introducing discontinuities into the structure of the first carbon coating layer. As such, Kang’s first carbon coating layer is inherently a discontinuous layer (claim 17).
Kang’s second carbon coating prevents exposure of Li byproducts on the lithiated core/first carbon coating composite on the surface when forming a negative electrode slurry (Kang [0009-0010], [0029]). A skilled artisan would recognize that layer discontinuities or incomplete encapsulation would render Kang’s second carbon coating layer unsuitable by exposing Li byproducts on the core/first carbon coating; it follows that Kang’s second carbon coating layer is necessarily a continuous layer which completely encapsulates the first carbon coating layer and the core on which it is disposed in order to perform its function (claim 17).
Kang does not explicitly indicate a thickness of the second coating layer as being less than the first coating layer, but a skilled artisan would need to select at least some relation of the second coating layer thickness relative to the first coating layer, with the only possible configurations being a second coating layer thickness less than, equal to, or greater than the first coating layer.
It would therefore have been obvious for one of ordinary skill in the art to routinely explore the selection of a second coating layer thickness less than the first coating layer thickness from the finite number of possible thickness configurations with a reasonable expectation of successfully forming the carbon coating layers (claim 17) (MPEP 2143 I. E).
Kang’s first carbon coating may be formed from a mixture of crystalline (i.e., graphitic) and amorphous carbon ([0037]), and second carbon coating is formed consisting essentially of amorphous carbon ([0012]) (claim 18).
While Kang does not explicitly disclose an electrical conductivity of the first or second carbon coating layer, inst. spec. [0076] indicates that the first carbon coating layer comprising a higher concentration of graphitic carbon exhibits higher electrical conductivity relative to the amorphous second carbon coating layer such that an electrical conductivity of Kang’s first amorphous/graphitic carbon coating layer is inherently greater than that of the amorphous second carbon coating layer (claim 17).
Regarding claim 19, modified Kang discloses the negative electrode of Claim 17. While Kang does not explicitly disclose the amount of lithium by weight in the electroactive material particle, Kang teaches mixing at least 2 parts Li metal powder to 98 parts by weight of the core and first carbon coating layer when lithiating the core material to increase the initial efficiency ([0076]), and mixing less than 30 parts Li metal to 70 parts by weight of the core and first layer to prevent excessive generation of reaction byproducts ([0076]).
As such, in balancing considerations of initial efficiency and byproduct generation, it would be obvious before the effective filing date of the instant application for one having ordinary skill in the art to optimize the amount of Li metal powder used to lithiate Kang’s negative electrode material; see MPEP 2144.05 II. In doing so, one would also optimize a weight of lithium in the electroactive material particle; while Kang does not disclose an exact weight, given that a weight percentage of lithium as a raw material ranges from 2-30 wt%, one having ordinary skill in the art could reasonably have utilized the similar claimed range of 5-15 wt%.
Furthermore, Kang discloses at least 0.05 wt% of first carbon coating layer is provided to control a reaction between Li metal powder and the silicon-based core during manufacture ([0037-0038]), and at least 1 wt% secondary carbon coating material is provided to prevent side reactions with an aqueous binder ([0035]). Additionally, unlike the silicon-based core material ([0083]), Kang does not indicate the carbon coatings contribute significantly to lithium storage, such that a skilled artisan would avoid excessive amounts of the carbon coatings in the interest of maximizing energy density.
Thus, in seeking to balance providing sufficient protection with the first/second carbon coatings while maximizing energy density, it would be obvious for one having ordinary skill in the art to optimize the total coating weight between 1.05%-35 wt%, this range approximately encompassing the claimed range of 1-10%; see MPEP 2144.05 II
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Kang as applied to claim 17, further in view of Liu et al. US20160020453A1 (cited in IDS filed 08/08/2022)
Regarding claim 20, modified Kang discloses the negative electrode of Claim 17. While Kang discloses that the electroactive particles have improved controllability over volume expansion (Kang [0023]), Kang does not indicate that the weight of the electroactive material particles accounts for 90% to 98% of the weight of the negative electrode.
Liu, directed to a negative electrode having a silicon-based particle (14, “silicon particle”) teaches a carbon coating layer (28) (Liu [0053-0054], FIG. 2) similarly provided to enhance the mechanical strength of the electroactive particle (10, “active material”) to prevent fracturing and mechanical degradation during cycling ([0061]). Liu further teaches that a proportion of the electroactive particle (10) in the electrode ranges from 50% to 90% based on a total solid weight of the slurry ([0096]).
As such, it would be obvious before the effective filing date of the instant application for one having ordinary skill in the art to produce modified Kang’s negative electrode wherein the electroactive material particles account for 90% of the negative electrode by weight as taught by Liu. Such a selection would be made with a reasonable expectation of success due to the similar structures of electroactive material particle and the similar advantages of improved resistance to volume expansion and mechanical degradation between modified Kang and Liu.
Response to Arguments
Applicant’s arguments with respect to amended claims 11, 17 (Remarks pp. 8-9) have been considered but are moot because the arguments are drawn to the claim amendment which has necessitated new grounds of rejection discussed above.
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.
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/E.C./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 2/27/2026