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
Claims 1 and 10 are amended. Claims 1-18, as filed 14 April 2026, are examined herein. No new matter is included.
Response to Arguments
Regarding the rejection under 35 USC 103, Applicant argues that Zhang does not teach or suggest two negative electrode layers arranged in the thickness direction and does not teach or suggest a step structure where the negative electrode layers have different edge positions. Applicant argues that Hirai does not teach or suggest the claimed edge alignment constraints and further argues that none of the cited references identifies edge alignment as related to lithium precipitation, short-circuit prevention, or edge bulging. This is not persuasive. Hirae at [0004] contemplates that one way to prevent shorting is to reduce the thickness of the end portions of the active material layers. Hirae solves this problem while maintaining overall active material layer thickness by using two layers with a step, as set forth at Hirae FIG. 3 and [0015]. Hirae also at [0005] contemplates that at higher application speeds, formation control of the end portions of the active material layers is an issue (e.g. edge bulging). Hirae’s double layer negative electrode solves this issue.
Regarding Examiner’s argument that "If the step is too large, the separator will not be fully supported and the battery will become physically unstable, and also some of the positive active material will not have corresponding negative active material, causing a battery with reduced capacity and safety, as shown in Examiner's FIG. 1, below,” Applicant argues that “this conclusion is not supported by the cited references and relies on an unsupported inference drawn from schematic drawings, rather than on any technical disclosure. First, the cited references do not teach or suggest that separator support depends on a specific vertical stacking orientation in which the negative electrode plate must be positioned beneath the separator. In practical battery manufacturing, as understood by a person of ordinary skill in the art, electrode stacking order is flexible. The orientation shown in a schematic figure is illustrative only and does not define a structural limitation or mechanical dependency.” This is not persuasive. Lee at [0007] contemplates that deformation of the anode can cause deterioration of the anode and of the battery life. (e.g. reduced capacity and safety, as stated by Examiner with respect to Examiner’s FIG. 1) At [0009], Lee contemplates the use of the inventive two layer negative active material as improving mechanical stability and operational reliability.
Regarding Takewara as evidentiary support, Applicant argues that “FIG. 1 of Takewara clearly illustrates a horizontal stack configuration, in which the separator does not rely on structural support in the manner asserted in the Office Action” and “Further, the assertion in the Office Action neglects the fact that, in the field of lithium-ion batteries, the electrode layers and separator are typically closely laminated, wound, or stacked and may be bonded through binders or compressed during cell assembly. A person of ordinary skill in the art would understand that such bonding or compression inherently provides sufficient mechanical stability to the separator.” This is not persuasive. Examiner notes that separator material is a porous film, for example polyethylene. (Hirae at [0056], Zhang at [0035]) Therefore, the separator material will be flexible to some extent. Examiner agrees that “the electrode layers and separator are typically closely laminated, wound, or stacked and may be bonded through binders or compressed during cell assembly.” Examiner notes that a large overhang, as illustrated in Examiner’s FIG. 1, could potentially experience fracture of negative active layer 1 or of the positive current collector during the compression step. Fracture of active material layers is known to have adverse effects on cell performance.
Claim Interpretation
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. Claims 1-5, 8-14, and 17-18 include the term “edge distance”. Referring to [0054] of the instant specification, "the first negative electrode layer exceeds the second electrode layer at both ends … alleviating edge bulging and reducing thickness and volume … improving energy density." For the purpose of clarity, an “edge distance” is an overhang distance as shown in the instant FIG. 1, where the overhang distance is viewed from a direction perpendicular to the plane of the positive current collector.
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.
Claim(s) 1-5, 8-14, and 17-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang (US 20150091530 A1) in view of Hirai (US 20200295345 A1), with evidentiary support from Takewara (US 20020081485 A1).
Regarding claims 1 and 10, Zhang teaches an electrochemical apparatus (abstract: lithium-ion cell), comprising:
a positive electrode plate, wherein the positive electrode plate comprises a positive electrode active material layer; and ([0032] LFP on aluminum foil; Table 1 “cathode dimensions … 148 mm x 194 mm)
a negative electrode plate, wherein the negative electrode plate comprises a negative electrode current collector, a first negative electrode active material layer ([0033] “anode was constructed of 94 wt% graphite … casted onto copper foil”; Table 1 “anode dimensions … 151 mm x 199 mm)
a separator is disposed between the positive electrode active material layer and the second negative electrode active material layer. ([0035] “anode and cathode were stacked with a separator of porous polyethylene”)
Zhang does not explicitly teach a second negative electrode active material layer, and the first negative electrode active material layer is provided between the negative electrode current collector and the second negative electrode active material layer.
Hirai, in the field of (abstract) manufacturing electrodes for an electrochemical device, discloses at [0012] the use of an electrode having two layers of active material to control end portion shape. At [0015] “the active material layers comprise a lower active material layer formed on the current collector
and an upper active material layer formed on the lower active material layer.” At [0016] “The present
invention can reduce the discarded portions thereby decreasing manufacturing costs to a lower level.” At FIG. 3, the negative electrode is shown with two layers of negative active material 12a, 12b on both sides of the current collector 11, with manufacturing steps shown at FIG. 5 to FIG. 7.
A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to select the two-layer electrode forming process of Hirai for the negative electrode of Zhang, with a reasonable expectation of controlling end portion shape and lowering manufacturing costs. Examiner notes that this creates a cell having at two-layer negative electrode with a “step” between the first and second layers.
Hirai does not explicitly teach the distance of the step between 1st and the second negative active layer. However, a person of ordinary skill would understand that if the step is too small, the benefits of controlling end portion shape and reducing material waste will not be achieved. If the step is too large, the separator will not be fully supported and the battery will become physically unstable, and also some of the positive active material will not have corresponding negative active material, causing a battery with reduced capacity and safety, as shown in Examiner’s FIG. 1, below.
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Therefore, the person of ordinary skill would be motivated to optimize the step size of the 2nd negative active material layer, in order to balance controlling end portion shape with having a battery with reduced capacity and safety. A reasonable result is to fully support the positive active layer, but not have the second negative electrode layer extend beyond the area of the positive electrode layer, creating the cell as shown in Examiner’s FIG. 2, below.
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Returning to Zhang (as modified by Hirai), Zhang further teaches wherein, in a length direction, the first negative electrode active material layer has a first edge and a second edge; in the length direction, the second negative electrode active material layer has a third edge and a fourth edge; in the length direction, the positive electrode active material layer has a fifth edge and a sixth edge; the first edge, the third edge, and the fifth edge being located on a first side in the length direction; the second edge, the fourth edge, and the sixth edge being located on a second side in the length direction; the second side being opposite to the first side; As shown in Examiner’s FIG. 2, the first edge exceeds the third edge and the fifth edge in the length direction;
Regarding the limitation a distance between the third edge and the fifth edge in the length direction is less than 2 mm, the optimization of the second negative electrode layer to fully support, but not exceed beyond, the positive active material layer, was rendered obvious, above.
With respect to the optimization of the size on the positive electrode active material layer and the negative active material layers of Zhang as modified by Hirai, evidentiary support is provided by Takekawa, in the field of (abstract) a non-aqueous rechargeable battery for a vehicle. Takekawa at FIG. 2A to FIG. 7C and FIG. 8 shows total battery capacity with respect to the capacity and reversible rate of the positive active material and the negative active material. At [0019] Takekawa contemplates that “the positive electrode capacity and the negative electrode capacity can be balanced with each other so as not to have surplus or deficiency in the mutual capacities in a charge/discharge reaction. Also, the combination of the positive electrode and the negative electrode capable of obtaining the maximum capacity per unit weight of the active material can be provided, while considering the battery capacity reduction resulting from the irreversible capacity of the negative electrode. Said differently, within some reasonable ranges, there may not be any functional difference between the cell of Examiner’s FIG. 2, where there is an offset between the first and second negative active layer on one side, and Examiner’s FIG. 3, where the offset is found on both sides. A primary decision factor for the person of ordinary skill is to balance capacities of the positive and negative active materials, by adjusting the volume of each. The decision of how the material of second negative active layer is placed on the first active material layer is - after considering the need for end portion control as taught by Hirai, and within a reasonable limit of the second negative active layer being entirely supported by the first negative active material layer - a design choice. Therefore, a person of ordinary skill could choose to symmetrically stack the negative active material layers, as shown in Examiner’s FIG. 3, with a reasonable expectation of creating a successful battery.
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Further regarding claim 10, Zhang teaches at [0003] a cellular phone, which is an example of an electronic apparatus comprising a battery.
Regarding claims 2 and 11, Zhang in view of Hirai and Takewara renders obvious all of the limitations as set forth above, and further renders obvious wherein the distance between the third edge and the fifth edge in the length direction is 0.
Regarding claims 3 and 12, Zhang in view of Hirai and Takewara renders obvious all of the limitations as set forth above, and further renders obvious wherein the second edge exceeds the fourth edge and the sixth edge in the length direction. (As shown in Examiner’s FIG. 3)
Regarding claims 4-5 and 13-14, Zhang in view of Hirai and Takewara renders obvious all of the limitations as set forth above, and further renders obvious the limitation of claims 4 and 13 wherein a distance between the fourth edge and the sixth edge in the length direction is less than 2 mm, and the limitation of claims 4 and 14, wherein the distance between the fourth edge and the sixth edge in the length direction is 0. (As set forth in claim 1, a person of ordinary skill would understand that if the step is too large, the separator will not be fully supported and the battery will become physically unstable, and also some of the positive active material will not have corresponding negative active material, causing a battery with reduced capacity and safety. The person of ordinary skill would be motivated to make the 2nd negative active material layer large enough to fully support the positive active layer, to avoid a loss of capacity and a reduction in battery safety. The choice of a step or no step between the 2nd and 4th steps is a design choice (as discussed in claim 1 and incorporated herein by reference) therefore rendering obvious the selection of the distance between the fourth edge and the sixth edge in the length direction is 0.
Regarding claims 8 and 9, Zhang in view of Hirai and Takewara renders obvious all of the limitations as set forth above, and Zhang further teaches wherein a distance between the first edge and the fifth edge in the length direction is 2 mm to 8 mm. (Table 1: 199mm – 194mm = 5mm, therefore the overhang is 2.5mm per side) This also renders obvious the limitation of claim 9, wherein a distance between the second edge and the sixth edge in the length direction is 2 mm to 8 mm.
Claim(s) 6-7 and 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang (US 20150091530 A1) in view of Hirai (US 20200295345 A1), with evidentiary support from Takewara (US 200200818485 A1), as set forth in claims 1 and 10, above, and in further view of Lee (US 20200365883 A1)
Regarding claims 6 and 15, Zhang in view of Hirai and Takewara renders obvious all of the limitations as set forth above, but these references are silent on the thickness ratio between the first and second layers, and therefore do not teach wherein a thickness of the second negative electrode active material layer is greater than a thickness of the first negative electrode active material layer.
Lee, in the field of (abstract) lithium secondary batteries, teaches [0086] “… a ratio of the loading weight of the second anode slurry to the loading weight of the first anode slurry may be …. preferably about 2 to 4.” Examiner notes that loading weight is proportional to volume, and therefore a loading weight ratio of 2 to 4 will create a thicker second electrode layer than the first electrode layer, even accounting for some overhang of the first electrode layer. At [0076] and [0066] Lee contemplates the first anode active material layer having a binder selected for adhesion properties to the current collector, and the second binder (acryl-based) selected for high modulus to maintain stable capacity and output. At [0087] Lee contemplates that “Accordingly, electrode expansion may be sufficiently suppressed through the acryl - based binder and output and capacity may be sufficiently improve through the silicone - based active material.”
A person of ordinary skill in the art would have been motivated, as of before the effective filing date of the instant invention, to select a thicker second electrode layer as comparted to the first electrode layer of modified Zhang, based on the teachings of Lee, with a reasonable expectation of successfully suppressing undesirable electrode expansion.
Regarding claims 7 and 16, Zhang in view of Hirai, Takewara, and Lee renders obvious all of the limitations as set forth above. Zhang further teaches wherein the first negative electrode active material layer or the second negative electrode active material layer further comprise a negative electrode active material, and the negative electrode active material comprises ([0033] 94 wt% graphite), which is a candidate within the scope of the claimed list of alternatives.
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 CLAIRE A RUTISER whose telephone number is (571)272-1969. The examiner can normally be reached 9:00 AM to 5:00 PM M-F.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jonathan Leong can be reached at 571-270-1292. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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CLAIRE A. RUTISER
Examiner
Art Unit 1751
/C.A.R./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 9/22/2026
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