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
This is a final office action for application 17/791,101 in response to the amendment(s) filed on 05/29/2026. Claims 1-4, 10-11 and 15-18 are under examination. Claims 5-9 and 12-14 remain withdrawn from consideration.
Response to Arguments
Applicant’s arguments filed on 05/29/2026 have been fully considered but were not found persuasive over the previously applied prior art rejection of record for the reasons set for below. See claims 1-4, 10-11 and 15-18 rejections below.
First in regards to the limitation “essentially the entire surface”, claim 1 does not define “essentially the entire surface” as requiring complete or continuous coverage, nor does the claim recite a minimum percentage of surface coverage or required coating. The specification similarly provides no quantitative standard for “essentially” and expressly identifies physical vapor deposition as a suitable coating method (see e.g. paragraph [0073] of the instant specification). Thus applicant’s argument in regards to the masked immersion coating embodiment improperly reads an unclaimed process limitations into the apparatus claim.
Furthermore, Hou teaches depositing a substantially uniform Au lithiophilic coating on the backside surfaces of CuF ligaments throughout a three dimensional porous structure. Figure 1b shows the lithiophilic layer extending through the interior porous network and Figures 3a-3f show lithium nucleation and growth throughout the internal pores on the Au coated backside regions. Although Figure 3f depicts lithium growth rather than the Au layer itself, it demonstrates that lithiophilic regions are distributed throughout the internal porous structure. The characterization of Hou’s sputtering process as “line of sight” does not establish that the internal pore surfaces remain uncoated, particularly where Hou continually rotates the open cell substrate to obtain uniform coating.
To the extent Hou does not expressly describe the extent of the internal coating using the words “essentially the entire surface,” Lai discloses uniformly distributing lithiophilic metal on the skeleton of a three dimensional porous current collector so that the internal surface area is effectively utilized for uniform lithium deposition (see e.g. paragraph [30] of Lai). Thus it would have been obvious to a person of ordinary skill in the art, to modify the lithiophilic layer of Hou such that the lithiophilic material is uniformly distributed throughout the porous skeleton as taught by Lai in order to increase internal lithium nucleation sites while preventing lithium growth toward the separator as suggested by Lai.
In conclusion, the arguments and amendments filed were not found to be persuasive over the previous prior art rejection of record. The rejections of the claims have been updated to reflect the amendments where appropriate. See claims 1-4, 10-11 and 15-18 rejections below.
Claim Rejections - 35 USC § 103
Claims 1-4, 10-11 and 15-19 are rejected under 35 U.S.C. 103 as being unpatentable over Hou et al. (Growth direction control of lithium dendrites in a heterogeneous lithiophilic host for ultra-safe lithium metal batteries, 06 February 2019, Journal of Power Sources, Volume 416) and further in view of Lai et al. (CN 110828829 A).
Regarding Claim 1, Hou discloses a negative electrode for lithium secondary batteries (see e.g. Abstract and Section 2.1), the negative electrode comprising:
a negative electrode current collector comprising a porous structure having an inner pore (see e.g. “commercially available copper foam” in Section 2.1; “interior pores of the 3D porous structure” in the Introduction; and FIGs. 1b and 2);
wherein a lithiophilic material is formed on a surface of and within the inner pore of the porous structure, excluding a first surface of the negative electrode current collector that faces a positive electrode (see e.g. “lithiophilic layer coated on the ‘backside’ surface” in the Introduction; “Gold (Au) layer was deposited onto one side of CuF” and “continual rotating of the substrate guaranteed a uniform coating” in Section 2.1 and FIGs. 1b and 2e-2h). Hou further discloses that the non-Au-coated surface faces the separator, and therefore the positive electrode, during battery operation (see e.g. Section 2.3).
Hou further teaches that the lithiophilic material is formed on essentially the entire surface of the inner pore. Specifically, FIG. 1b shows the lithiophilic layer extending throughout the interior porous network along the backside facing surfaces of the CuF ligaments, and FIGs. 2e-2h show Au distributed across the backside porous structure. FIGs. 3a-3f further show lithium nucleation and growth throughout the interior pores on the Au coated backside regions, demonstrating that the lithiophilic regions extend throughout the internal porous structure.
The claim does not define “essentially the entire surface,” require complete or continuous coverage, or specify a minimum percentage of surface coverage. Accordingly, under the broadest reasonable interpretation, Hou’s substantially uniform distribution of Au throughout the backside facing internal surfaces of the porous structure satisfies the claimed “essentially the entire surface” limitation.
To the extent Hou does not expressly describe the extent of the internal coating using the words “essentially the entire surface,” Lai teaches uniformly distributing a lithiophilic metal throughout the skeleton of a three dimensional porous current collector (see e.g. paragraph [30] of Lai) and electroplating Au, Ag, or Pt onto the skeleton of the three dimensional porous current collector (see e.g. paragraphs [35]-[36] of Lai).
Hou does not disclose that the negative electrode current collector has a thickness of 5 μm to 30 μm.
Lai, however, discloses that the three dimensional porous current collector preferably has a thickness of 20 μm to 50 μm (see e.g. paragraph [53] of Lai).
Lai therefore discloses a range overlapping the claimed range. When the prior art discloses a range that overlaps the claimed range, a prima facie case of obviousness exists. See MPEP 2144.05(I).
Lai further teaches that this type of 3D lithiophilic porous metal current collector can effectively maintain a stable skeleton during the lithium metal deposition process as well as allow for lithium deposition without dendrite formation during operation ultimately leading to a long cycle life (see e.g. paragraph [30] on page 5 of Lai). Therefore, it would have been obvious to a person of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the 3D porous negative electrode current collector of Hou et al. such that the 3D porous negative electrode current collector has a thickness between 20 µm and 50 µm and the lithiophilic layer is uniformly distributed through the 3D porous negative electrode current collector as taught by Lai et al. in order to allow for lithium to form on the negative electrode without the formation of dendrites which leads to longer battery cycle life as suggest by Lai.
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(Hou, figures 1b and 2, annotated for illustration)
Regarding Claim 2, Hou in view of Lai discloses the negative electrode according to claim 1 (see e.g. claim 1 rejection above).
With regards to the claim limitation "wherein lithium plating occurs on the lithiophilic material" this is a functional limitation and does not further limit the structure of the apparatus. Apparatus claims cover what a device is, not what a device does. See MPEP 2114 (II).
Hou, however, does disclose that lithium plating occurs on the lithiophilic material (see e.g. "As shown in Fig. 1b, during Li plating, Li nuclei start to form only on the Au coated backside surface of the skeleton in the initial stage due to its overwhelming preference for metallic Li to nucleate." in Introduction paragraph starting with "Here we tackle" and FIG. 1b; during the lithium growth phase lithium is only grown on the lithiophilic layer as compared to FIG. 1a where lithium plates all over the conductive matrix and no lithiophilic layer is present).
Regarding Claim 3, Hou in view of Lai discloses the negative electrode according to claim 1 (see e.g. claim 1 rejection above).
Hou further discloses that the lithiophilic material is a metal (see e.g. "Au without extra nucleation overpotential as the lithiophilic coating" in Introduction paragraph starting with "Here we tackle" and "Gold (Au) layer was deposited onto one side of CuF by magnetron sputtering" in Section 2.1 page 142).
Regarding Claim 4, Hou in view of Lai discloses the negative electrode according to claim 3 (see e.g. claim 3 rejection above).
Hou further discloses that the metal is Au (see e.g. "Au without extra nucleation overpotential as the lithiophilic coating" in Introduction paragraph starting with "Here we tackle" and "Gold (Au) layer was deposited onto one side of CuF by magnetron sputtering" in Section 2.1 page 142).
Regarding Claim 10, Hou in view of Lai discloses an electrode assembly (see e.g. "In the cells... CuF@Au electrodes were used as work electrodes and Li metal foil as counter electrode separated by a Celgard separator in an electrolyte of 1M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in cosolvent of 1,3-dioxolane (DOL) and 1,2-dimethoxyethane (DME) (volume ratio: 1:1) with 1.0 wt% LiNO3 (DoDo Chem)." in Section 2.3 paragraph beginning with "To characterize" spanning pages 142 and 1433 of Hou; CuF@Au is the electrode as described in claim 1 rejection above) comprising the negative electrode according to claim 1 (see e.g. claim 1 rejection above).
Regarding Claim 11, Hou in view of Lai discloses the electrode assembly according to claim 10 (see e.g. claim 10 rejection above).
Hou further discloses that the electrode assembly is a mono cell, in which two electrodes different from each other are disposed such that a separator is interposed therebetween (see e.g. "In the cells... CuF@Au electrodes were used as work electrodes and Li metal foil as counter electrode separated by a Celgard separator in an electrolyte of 1M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in cosolvent of 1,3-dioxolane (DOL) and 1,2-dimethoxyethane (DME) (volume ratio: 1:1) with 1.0 wt% LiNO3 (DoDo Chem)." in Section 2.3 paragraph beginning with "To characterize" spanning pages 142 and 143; CuF@Au is the electrode as described in claim 1 rejection above).
Regarding Claim 15, Hou in view of Lai discloses an electrode assembly (see e.g. "In the cells, CuF or CuF@Au electrodes were used as work electrodes and Li metal foil as counter electrode separated by a Celgard separator in an electrolyte of 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in cosolvent of 1,3-dioxolane (DOL) and 1,2-dimethoxyethane (DME) (volume ratio: 1:1) with 1.0 wt% LiNO3 (DoDo Chem)." in Section 2.3 paragraph beginning with "To characterize" spanning pages 142 and 143; CuF is the electrode without the lithiophilic material and CuF@Au is the electrode as described in claim 2 rejection above) comprising the negative electrode according to claim 2 (see e.g. claim 2 rejection above).
Regarding Claim 16, Hou in view of Lai discloses an electrode assembly (see e.g. "In the cells, CuF or CuF@Au electrodes were used as work electrodes and Li metal foil as counter electrode separated by a Celgard separator in an electrolyte of 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in cosolvent of 1,3-dioxolane (DOL) and 1,2-dimethoxyethane (DME) (volume ratio: 1:1) with 1.0 wt% LiNO3 (DoDo Chem)." in Section 2.3 paragraph beginning with "To characterize" spanning pages 142 and 143; CuF is the electrode without the lithiophilic material and CuF@Au is the electrode as described in claim 3 rejection above) comprising the negative electrode according to claim 3 (see e.g. claim 3 rejection above).
Regarding Claim 17, Hou in view of Lai discloses an electrode assembly (see e.g. "In the cells, CuF or CuF@Au electrodes were used as work electrodes and Li metal foil as counter electrode separated by a Celgard separator in an electrolyte of 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in cosolvent of 1,3-dioxolane (DOL) and 1,2-dimethoxyethane (DME) (volume ratio: 1:1) with 1.0 wt% LiNO3 (DoDo Chem)." in Section 2.3 paragraph beginning with "To characterize" spanning pages 142 and 143; CuF is the electrode without the lithiophilic material and CuF@Au is the electrode as described in claim 4 rejection above) comprising the negative electrode according to claim 4 (see e.g. claim 4 rejection above).
Regarding Claim 18, Hou in view of Lai discloses the negative electrode according to claim 1 (see e.g. claim 1 rejection above).
Hou further teaches that the lithiophilic material is formed on essentially the entire surface of the negative electrode current collector except the first surface that faces the positive electrode. Specifically, Hou deposits Au on one side of the CuF and teaches that continual rotation of the substrate guarantees a uniform coating (see e.g. Section 2.1). FIGs. 2e-2h show Au distributed across the backside surface of the porous CuF structure, whereas FIGs. 2a-2d show that the separator facing surface remains substantially free of Au. FIG. 1b similarly shows the lithiophilic layer extending throughout the porous structure along the backside facing surfaces of the CuF ligaments. FIGs. 3a-3f further show lithium nucleation and growth throughout those backside regions, demonstrating that the underlying lithiophilic regions are distributed throughout the porous current collector.
The claim does not define “essentially the entire surface,” require complete or continuous coverage, or specify a minimum percentage of the current collector surface that must be coated. Accordingly, under the broadest reasonable interpretation, Hou’s substantially uniform Au coating distributed throughout the backside surfaces of the porous current collector, while leaving the separator facing first surface substantially uncoated, satisfies the claimed limitation.
To the extent Hou does not expressly describe the coating using the words “essentially the entire surface,” Lai teaches uniformly distributing a lithiophilic metal throughout the skeleton of a three dimensional porous current collector in order to utilize the effective internal surface area, promote uniform lithium nucleation, prevent dendrite formation, and improve cycle life (see e.g. paragraph [30] and paragraphs [35]-[36] of Lai).
Lai further teaches that this type of 3D lithiophilic porous metal current collector can effectively maintain a stable skeleton during the lithium metal deposition process as well as allow for lithium deposition without dendrite formation during operation ultimately leading to a long cycle life (see e.g. paragraph [30] on page 5 of Lai). Therefore, it would have been obvious to a person of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the 3D porous negative electrode current collector of Hou et al. such that the lithiophilic layer is uniformly distributed through the 3D porous negative electrode current collector as taught by Lai et al. in order to allow for lithium to form on the negative electrode without the formation of dendrites which leads to longer battery cycle life as suggest by Lai.
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(Hou, figure 3f, annotated for illustration)
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's
disclosure:
Chang et al. (US-20220158226-A1)
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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/J.J.E./Examiner, Art Unit 1723
/NICHOLAS P D'ANIELLO/Primary Examiner, Art Unit 1723
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