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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 4/2/2026 has been entered.
Status of Claims
This action is responsive to the amendment filed 11/29/2024. Claims 1-5, 7-18, 20 and 21 are pending, claims 1 and 16 are amended, and claims 6 and 19 are cancelled.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-5, 7-8, 11-18 and 20-21 are rejected under 35 U.S.C. 103 as being unpatentable over Piggott et al. (US 9,899,711, herein Piggott) in view of Zhamu et al. (US 2008/0277628, herein Zhamu).
In regards to claim 1, Piggott discloses a cooling system (Fig. 4) for a battery module or pack comprising one or a plurality of battery cells (12), the system comprising a graphitic heat spreader element (28; col. 20, lines 10-14) configured to be in thermal communication with the battery cells; and
a cooling device (20, 26, 32a and 32b) in thermal communication with the graphitic heat spreader element and configured to transport heat generated from the battery cells through the graphitic heat spreader element to the cooling device when the battery cell is discharged,
wherein said graphitic heat spreader element comprises a graphitic film selected from a flexible graphite sheet (col. 21, lines 10-14 and col. 26, lines 35-36, heat spreader element 28 comprises a flexible pyrolytic graphite sheet).
Piggott does not specifically disclose the flexible graphite sheet comprising exfoliated carbon fibers.
Zhamu teaches flexible graphite sheets made from expanded or exfoliated graphite flakes or carbon fibers (the exfoliated graphite particles having a vermiform in appearance, paragraph 12, such particles in a vermiform resemble fiber structure as claimed).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide a flexible graphite sheet comprised of expanded graphite flakes or exfoliated carbon fibers as taught by Zhamu since these are well known aspects of flexible graphite sheets in the art. Since Piggott already discloses “flexible graphite”, it is understood in the art that such sheets include exfoliated graphite particles of fibers. Zhamu further provides evidence for this in paragraph 12 as a known feature of flexible graphite sheets.
In regards to claim 2, Piggott discloses a thermal interface material (TIM) coupled to at least one of the battery cells and the heat spreader element (graphite sheet 42 as a thermal interface material, col. 25, lines 16-20).
In regards to claim 3, Piggott discloses that said graphitic heat spreader element is in a form of a film, sheet, layer, belt, or band having a thickness from about 100 nm to 10 mm (25 µm, col. 21, lines 21-24).
In regards to claim 4, Piggott discloses that said graphitic heat spreader element has a thermal conductivity no less than 200 W/mK (1700 W/m-K, col. 18, lines 33-36).
In regards to claim 5, Piggott discloses that said graphitic heat spreader element has a thermal conductivity no less than 1,000 W/mK (1700 W/m-K, col. 18, lines 33-36).
In regards to claim 7, Piggott discloses that thermal interface material comprises a material selected from graphene sheets, graphene foam, graphene-containing paste, graphite flake- containing paste, graphene-containing polymer composite, flexible graphite sheet, artificial graphite film, particles of graphite, Ag, Ag, Cu, Al, brass, steel, Ti, Ni, Mg alloy, silicon nitride, boron nitride, aluminum nitride, boron arsenide, a composite thereof, or a combination thereof (the graphene sheets 42, col. 25, lines 16-20).
In regards to claim 8, Piggott discloses that said thermal interface material is electrically insulating and thermally conducting, having a thermal conductivity no less than 1 W/mK (col. 18, lines 23-36).
In regards to claim 11, Piggott discloses that the cooling device is selected from a heat sink, a heat pipe, a vapor chamber, a stream of flowing fluid, a bath of a coolant fluid, a thermoelectric device, a heat exchanger, a cooled plate, a radiator, or a combination thereof (Fig. 4, fins 26 and heat sink 32).
In regards to claim 12, Piggott discloses that the heat spreader element is in a heat-spreading relation to a surface of the battery cell and receives heat therefrom when the battery cell is discharged to power an external device (the heat spreader 28 contacts a surface of each battery 12 and dissipates heat from each battery 12, Fig. 4).
In regards to claim 13, Piggott discloses that the heat spreader element is configured to form multiple lodging sites for accommodating individual battery cells (slots for placement of each battery 12, Fig. 4).
In regards to claim 14, Piggott discloses that said lodging sites comprise cylindrical pores to accommodate cylindrical-shape battery cells or rectangular pores to accommodate rectangular-shape battery cells (slots openings for each battery 12, Fig. 18).
In regards to claim 15, Piggott discloses that the battery module comprises a lithium-ion battery, lithium metal secondary battery, lithium-sulfur battery. lithium-air battery, lithium-selenium battery, sodium-ion battery, sodium metal secondary battery, sodium-sulfur battery. sodium- air battery, magnesium-ion battery, magnesium metal battery, aluminum-ion battery. aluminum metal secondary battery, zinc-ion battery, zinc metal battery, zinc-air battery. nickel metal hydride battery, lead acid battery, lead acid-carbon battery, lead acid-based ultra-battery, lithium-ion capacitor, or supercapacitor (col. 14, line 51).
In regards to claim 16, Piggott discloses a method of operating a battery cooling system (Fig.4), said method comprising:
(a) bringing a graphitic heat spreader element (28; col. 20, lines 10-14) in thermal contact with one or a plurality of battery cells (12) in a module or pack to receive heat generated from the battery cells, wherein said graphitic heat spreader element comprises a graphitic film selected from a flexible graphite sheet (col. 21, lines 10-14 and col. 26, lines 35-36, heat spreader element 28 comprises a flexible pyrolytic graphite sheet); and
(b) directing the heat to transport through the graphitic heat spreader element to a cooling device (20, 26, 32a and 32b) which acts to remove the heat and keeps a battery temperature at or below a desired temperature (Fig. 4).
Piggott does not specifically disclose the flexible graphite sheet comprising exfoliated carbon fibers.
Zhamu teaches flexible graphite sheets made from expanded or exfoliated graphite flakes or carbon fibers (the exfoliated graphite particles having a vermiform in appearance, paragraph 12, such particles in a vermiform resemble fiber structure as claimed).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide a flexible graphite sheet comprised of expanded graphite flakes or exfoliated carbon fibers as taught by Zhamu since these are well known aspects of flexible graphite sheets in the art. Since Piggott already discloses “flexible graphite”, it is understood in the art that such sheets include exfoliated graphite particles. Zhamu further provides evidence for this in paragraph 12 as a known feature of flexible graphite sheets.
In regards to claim 17, Piggott discloses that a thermal interface material (graphene sheets 42, col. 25, lines 16-20) is disposed between a surface of a battery cell and the graphitic heat spreader element.
In regards to claim 18, Piggott discloses that said graphitic heat spreader element has a thermal conductivity from 10 W/mK to 1,750 W/mK (1700 W/m-K, col.18, lines 33-36).
In regards to claim 20, Piggott discloses that said thermal interface material comprises a material selected from graphene sheets, graphene foam, graphene-containing paste, graphite particle- containing paste, graphene-containing polymer composite, flexible graphite sheet, artificial graphite film, particles of Ag, Ag, Cu, Al, brass, steel, Ti, Ni, Mg alloy, silicon nitride, boron nitride, aluminum nitride, boron arsenide, a composite thereof, or a combination thereof (the graphene sheets 42, col. 25, lines 16-20).
In regards to claim 21, Piggott discloses that the cooling device is selected from a heat sink, a heat pipe, a vapor chamber, a stream of flowing fluid, a bath of a coolant fluid, a thermoelectric device, a cooled plate, a heat exchanger, a radiator, or a combination thereof (Fig. 4, fins 26 and heat sink 32).
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Piggott in view of Zhamu as applied to claim 2 above, and further in view of Muramatsu et al. (US 2019/0241435, herein Muramatsu).
In regards to claim 9, Piggott does not disclose that said thermal interface material comprises a plastic or rubbery matrix composite containing graphene sheets, expanded graphite flakes, or a combination thereof.
Muramatsu teaches a thermal interface material (Fig.6) comprising a plastic or rubbery matrix (12) composite containing graphene sheets, expanded graphite flakes, or a combination thereof (11).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Piggot’s thermal interface material to comprise rubbery matrix composite containing graphene sheets, expanded graphite flakes, or a combination thereof as taught by Muramatsu in order to increase flexibility of the thermal interface material (see Muramatsu, paragraph 49).
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Piggott in view of Zhamu as applied to claim 2 above, and further in view of Yuen et al. (US 2014/0110049, herein Yuen).
In regards to claim 10, Piggott does not disclose that said thermal interface material comprises a graphene foam having a thermal conductivity from 0.1 W/mK to 100 W/mK.
Yuen teaches a thermal interface material (Fig.1, 105) comprising a graphene foam having a thermal conductivity from 0.1 W/mK to 100 W/mK (paragraphs 5 and 24).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Piggott’s thermal interface material to comprise graphene foam having the claimed thermal conductivity as taught by Yuen in order to increase heat exchange between the battery cells and the heat spreader element.
Response to Arguments
Applicant's remarks filed 5/14/2025 have been fully considered but they are not persuasive.
Applicant is requesting the teaching of "exfoliated carbon fibers" in Zhamu. The office action of 2/14/25 referred to paragraph 12 of Zhamu.
In particular, Zhamu teaches in paragraph 12, "The "flexible graphite" is the expanded or exfoliated reaction product of rapidly heated natural graphite particles which have been treated with an agent that intercalates into the crystal structure of the graphite to expand the intercalated particles typically 80-300 times in the direction perpendicular to the carbon layers in the crystal structure. The exfoliated graphite particles are vermiform in appearance, and are therefore commonly referred to as worms. Hereinafter, the term "exfoliated graphite" will be used interchangeably with the term "expanded graphite." The worms may be compressed together into flexible sheets which, unlike the original graphite flakes, can be formed and cut into various shapes. These thin sheets (foils or films) are hereinafter referred to as flexible graphite. Flexible graphite can be wound up on a drum to form a roll of thin film, just like a roll of thin plastic film or paper."
Zhamu uses the phrase "exfoliated graphite particles", which are equivalent to the "exfoliated carbon fibers" in claim 1. The particles of Zhamu are vermiform in appearance similar to the appearance of fibers.
Therefore, the rejection is maintained.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). 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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/JIANYING C ATKISSON/Supervisory Patent Examiner, Art Unit 3763
/F.K.L/Examiner, Art Unit 3763
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