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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 01/07/2026 has been entered.
Response to Amendment
Claim 1 is amended. Claim 2 is cancelled. Claims 1, 3-4, 7-8, and 10-14 are pending review in this action.
A new grounds of rejection is presented below.
Response to Arguments
Applicant's arguments filed 01/07/2026 have been fully considered but they are not persuasive.
Applicant’s arguments with respect to the artificial graphite particles required by amended claim 1 have been considered but are moot because the new ground of rejection does not rely on Chen or Zhamu and does not rely on Kim to teach the artificial graphite particles.
Applicant argues the claimed content ratios produce unexpected results as argued during the Interview and in the November 26, 2024 amendment that are not disclosed or contemplated by the applied references.
Examiner respectfully disagrees. The new ground of rejection relies on a reinterpretation of Kim to teach the claimed weight ratio between graphite particles and the first carbon coating layer and newly cited Qiao to teach the claimed weight ratio between graphite particles and the second carbon coating layer. As discussed in the Interview of 10/02/2025 and Final Rejection of 10/09/2025, the data presented in the instant specification and the declaration of 04/30/2024 do not demonstrate the criticality of the claimed content ratios. The results obtained would flow naturally from the combined teachings of Hwang, Qiao, and Kim as set forth in the rejection 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, 3-4, 7-8, and 10-14 are rejected under 35 U.S.C. 103 as being unpatentable over Hwang (US 2018/0331354 A1) in view of Qiao (CN-106495143-A, a machine translation is attached and referenced below), and further in view of Kim (US 2017/0170465 A1; previously cited).
Regarding claim 1, Hwang discloses a method for preparing a negative electrode active material ([0135]), the method comprising:
disposing a pitch on graphite particles and performing a first heat treatment on the graphite particles to form a first carbon coating layer on the graphite particles ([0135]);
wherein the graphite particles comprise artificial graphite particles ([0133]) in the form of secondary particles ([0134]), and
wherein a temperature range for the first heat treatment is from 900 °C to 2000 °C (1100 °C, [0135]).
Hwang teaches the carbon coating layer may include a pitch and a resin ([0064]-[0065]) and a ratio of the graphite particle layers and the carbon coating layer is 1:0.005 to 1:0.1111 ([0014]), but does not disclose disposing a liquid resin on the first carbon coating layer and performing a second heat treatment on the graphite particles to form a second carbon coating layer, wherein the liquid resin is an amorphous liquid matter composed of an organic compound and a derivative thereof, wherein a weight ratio of the graphite particles and the first carbon coating layer is from 1.00000:0.0052 to 1.0000:0.0474, and wherein a weight ratio of the graphite particles and the second carbon coating layer is from 1.00000:0.0052 to 1.0000:0.0474.
Qiao teaches a method for preparing a negative electrode active material ([0009]), comprising forming a first carbon coating layer on graphite particles ([0010]); and disposing a liquid resin on the first carbon coating layer ([0011]) and performing a second heat treatment on the graphite particles to form a second carbon coating layer (carbonizing, [0013]), wherein the liquid resin is an amorphous liquid matter composed of an organic compound and a derivative thereof (water-soluble thermosetting phenolic resin, [0019]), and wherein a weight ratio of the graphite particles and the second carbon coating layer is from 1:0.0186 to 1:0.0472 (Examples 3 and 5, [0035], [0045]; general overlapping range of 1:0.005 to 1:0.0526, [0016]). A person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have modified the method of Hwang by adding a step of disposing a liquid resin on the first carbon coating layer and performing a second heat treatment on the graphite particles to form a second carbon coating layer, wherein the liquid resin is an amorphous liquid matter composed of an organic compound and a derivative thereof, and wherein a weight ratio of the graphite particles and the second carbon coating layer is from 1:0.0186 to 1:0.0472, reading on the claimed range of “from 1.00000:0.0052 to 1.0000:0.0474,” because Qiao teaches that adding a hard carbon shell layer to soft carbon-coated graphite improves anode rate performance ([0005]) and that forming the second coating using a water soluble thermosetting phenolic resin in such an amount yields a uniform coating and does not cause agglomeration of the finished product ([0019]).
Kim teaches a method for preparing a negative electrode active material ([0013]), comprising disposing a pitch on graphite particles and performing a heat treatment to form a first carbon coating layer on the graphite particles ([0087]; core particles may be artificial graphite, [0034]), wherein a weight ratio of the graphite particles and the first carbon coating layer is 1:0.0417 ([0087]; overlapping range of 1:0.0101 to 1:0.0638, [0040]), and wherein the weight ratio between the graphite particles and the first carbon coating layer is related to the thickness of the coating layer ([0040]). A person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have modified the method of Hwang in view of Qiao such that a weight ratio of the graphite particles and the first carbon coating layer is 1:0.0417 as taught by Kim in Example 1 ([0087]), or optimized said weight ratio to a value reading on the claimed range of 1.0000:0.0052 to 1.0000:0.0474 in order to achieve a desired balance between coating coverage, battery performance, and capacity as taught by Kim ([0040]). It has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art [MPEP § 2144.05(II)A].
Regarding claim 3, Hwang in view of Qiao and Kim teaches wherein the average particle diameter (D50) of the graphite particles ranges from 5 µm to 30 µm (Hwang: 15.3 µm in Example 1, [0134]; 10 µm to 25 µm, [0016]).
Regarding claim 4, Hwang in view of Qiao and Kim teaches wherein the pitch comprises at least one of a coal-based pitch and a petroleum-based pitch (Hwang: [0065]; Kim: [0041]).
Regarding claim 7, Hwang in view of Qiao and Kim teaches wherein the liquid resin comprises a phenol resin (Qiao: [0019]).
Regarding claim 8, Hwang in view of Qiao and Kim teaches wherein a temperature for the second heat treatment is 700°C to 1200°C (Qiao: [0017]), reading on the claimed range of “500°C to 2000°C.”
Regarding claim 10, Hwang in view of Qiao and Kim teaches wherein a weight ratio of the first carbon coating layer and the second carbon coating layer is from 47:53 to 69:31 (Kim: ratio of graphite to first carbon coating layer is 1:0.0417; Qiao: ratio of graphite to second carbon coating layer is 1:0.0186 to 0.0472, see rejection of claim 1), reading on the claimed range of “10:90 to 90:10.”
Regarding claim 11, Hwang in view of Qiao and Kim teaches wherein the second carbon coating layer is in contact with the first carbon coating layer (Qiao: [0010]-[0011]).
Regarding claim 12, Hwang in view of Qiao and Kim teaches wherein the step of performing the second heat treatment on the graphite particles to form the second carbon coating layer comprises forming an interface between the first carbon coating layer and the second carbon coating layer (instant specification, P30-31, indicates that an interface is formed the two coating layers are present).
Regarding claim 13, Hwang in view of Qiao and Kim does not explicitly disclose wherein the interface is configured to suppress the de-intercalation of lithium ions. However, the method of Hwang in view of Qiao and Kim is substantially identical to the claimed method, and therefore the resulting product is presumed to have the same properties. The Courts have held that where there is a reason to believe that a functional characteristic would be inherent in the prior art, the burden of proof then shifts to the Applicant to provide objective evidence to the contrary [MPEP § 2112.01].
Regarding claim 14, Hwang in view of Qiao and Kim teaches wherein the liquid resin is a phenol resin (Qiao: [0019]).
Conclusion
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/C.C.D./Examiner, Art Unit 1723 /TIFFANY LEGETTE/Supervisory Patent Examiner, Art Unit 1723
