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 .
Response to Amendment
This is a final Office action in response to Applicant’s remarks and amendments filed on 06/03/2026; Claim 1 is amended. Claims 2 – 3 and 8 – 9 are canceled. Claims 1 and 4 – 7, and 10 – 13 are pending in the current Office action.
The 35 U.S.C. 103 rejections set forth in the previous Office action are withdrawn and a new grounds of rejection, necessitated by applicant’s amendment is presented below {i.e. The claimed B2 range is a new limitation that was not previously considered}.
Response to Arguments
Applicant's arguments filed 03/05/2026 have been fully considered but they are not persuasive. Specifically, applicant argues none of the cited references, either individually in combination teaches/suggest the synergistic combination of controlling the highly specific absolute B2 range (1.65 to 2.41 m2/g, as provided in amended ind. claim 1) and the bimodal specific surface area ratio (40% to 90%, as provided in amended ind. claim 1) while simultaneously maintaining the asymmetric SiO weight distribution (0 < W1 ≤ 3 wt% and 9 ≤ W2 ≤ 12 wt%) as provided in amended ind. claim 1). Applicant further argues that Examples 8 – 9 demonstrate criticality/synergistic effect of the parameters that drive applicant’s unexpected results {i.e. superior capacity retention}.
Examiner acknowledges that , per Table 4, Examples 8 and 9, which have a content of SiO of 12 wt% and 9 wt% in the upper layer; however, as noted in the previous Office action, such a content of SiO, and thus applicant’s synergistic effects, only appear critical when the upper {i.e. second} active material has a specific surface area (B2) of 1.65 m2/g, the lower {i.e. first} active material has a specific surface area (B1) of 18 m2/g, and the ratio of the specific surface area of the first (B2-1) and second active materials (B2-2) included in the upper layer (B2-2/B2-1) is 0.72 {i.e. bimodal specific surface area is 72%} (Refer to Table 4), and as claim 1 allows for a significantly broader bimodal specific surface area range {i.e. 40 to 90%}, any selection of specific surface area for the first active material, and a broader specific surface area of the second active material {i.e. B2 is 1.65 to 2.41 m2/g} , it is unclear that the claimed W2 range would be critical across such broad bimodal specific surface areas, first active material specific areas, and second active material specific areas {i.e. the claimed invention still appears incommensurate in scope with the invention argued to provide the unexpected results/synergistic effect}.
Additionally, with respect to Examples 8 – 11, the examiner notes that the content of SiO is only varied/tested alongside a best-performing B2 specific surface area value {i.e. 1.62 m2/g} and bimodal specific surface area value {i.e. 72%} and that the B2 the specific surface area and bimodal specific surface area were not varied/tested along any varying SiO content (See Tables 1 – 3 and [0049 – 0051];[0065 – 0066]); thus it is unclear from the data provided in the instant specification if the SiO content, B2 specific surface area value, and bimodal specific surface area value are truly synergistic together. The examiner further notes based on Example 1, that the inclusion of SiO is not seemingly necessary to obtain a comparable capacity retention rate {i.e. without SiO Example 1 achieves capacity retention of 93% which is higher than Examples 8 and 9}.
The examiner further notes the following parameters, based on the instant specification, also appear to contribute to applicant’s unexpected results but are unbound by claim 1:
The specific surface area of the fist active material or B1/B2 {i.e. the specific surface area of the first active material/the specific surface area of the second active material} is not included within claim 1, whereas the instant specification recites that controlling the specific surface area of the first active material affects charging and discharging performance ([0031]), which one with ordinary skill in the art would understand to affect capacity retention. The examiner further notes that in Table 2, comparative Examples 1 and 2 appear to also explicitly show that the specific surface area of the first active material {i.e. B1} does have an effect on capacity retention. Therefore it is unclear if applicant’s results would occur for any specific surface area of the first active material.
The negative electrode active material type is not included within claim 1, whereas Table 3 and [0098] of the instant specification suggests that the type of graphite material included in the upper and lower active material layer affects capacity retention. Therefore it is unclear if applicant’s results would occur for any negative electrode active material {e.g. a non-carbon active material, etc.}.
Thus, in light of the above discussion, applicant’s arguments regarding the criticality and synergistic effects of the claimed parameters are unpersuasive and the pending case of obviousness appears proper.
Further, assuming arguendo, that the claimed parameter ranges were critical to achieving the alleged synergistic effects/superior results, the examiner respectfully notes that the data is further incommensurate with the scope of claim 1 for the following reason: the results stem from incorporating the negative electrode into a lithium secondary battery which utilizes liquid electrolyte (See [0061];[0082 – 0085]). As such, it is unclear if applicant’s results would occur when using a lithium secondary battery which utilizes, e.g. purely solid electrolyte, and absent evidence or a declaration explaining such a discrepancy, applicant’s showing of synergistic effects/superior results is not fully commensurate in scope and is further rendered unpersuasive {i.e. MPEP 716.02(d) requires showings of unexpected/superior results to be commensurate with the claimed scope}.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). Additionally, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In the instant case, the cited teaching references, as established in the rejection below, each provide benefits relevant/generic to two-layer, carbon-based negative electrodes {i.e. Thomas-Aleya and Soma} and/or negative electrodes that are carbon-based and include silicon-based active material as an additional active material {i.e. Lee} and thus provide benefits relevant to the primary reference: Sugimori which teaches a double layer, carbon-based negative electrode that has a larger amount of silicon-containing active material in the surface side-region than the current collector-side region.
The examiner further notes that, as established in the rejection below, Sugimori teaches overlapping ranges of SiO content and reasons to control the SiO content with respect to each layer of the active material, and Lee and Thomas-Aleya, relied upon by the examiner to render obvious the claimed specific surface area ranges, teach overlapping/encompassing specific surface area ranges as well as reasons for controlling the specific surface areas of electrode active material {i.e. low resistance and high rate characteristics vs. increases in side reactions} that are generic to double layer electrodes, and in case of Lee, further teaches controlling the amount of large/small specific surface area active material particles in an active material layer for reasons relevant to the composition of the modified second active material layer {i.e. counteracting the influence of large volume change of the silicon-based particles in the second active material layer and obtaining a negative electrode with high initial efficiency, excellent high-rate charge and discharge properties, cycle properties, and swelling properties}. As such, when the teachings of the prior art are considered together, and in light of applicant’s arguments regarding superior results and synergistic effects being unpersuasive, per MPEP 2144.05 and MPEP 2143, the pending case of obviousness appears proper and applicant’s arguments regarding the previously cited prior art are unpersuasive.
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 – 7, 10 – 11 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Sugimori (US PG Pub. 2016/0351892 A1, cited in previous Office action mailed 03/05/2026) in view of Soma (JP2017062911A, cited in previous Office action mailed 03/05/2026), Lee (US PG Pub. 2021/0202931 A1, cited in IDS filed 06/09/2026 - effective filing date of 10/26/2018), and Thomas-Aleya (US PG Pub. 2012/0328942 A1, cited in previous Office action mailed 03/05/2026).
Regarding Claim 1, Sugimori discloses a negative electrode for a secondary battery (Fig. 1 and 3, 14; [0015 – 0016];[0021]), comprising: a current collector (Fig. 1, 14a; [0021]); a first negative electrode active material layer formed on the current collector and containing a first active material (Fig. 1, 14b; [0021 – 0022]); and a second negative electrode active material layer formed on the first negative electrode active material containing a second active material (Fig. 1, 14c; [0021 – 0022]), wherein the first and second negative electrode active material layers further include a silicon oxide-based active material represented by the formula SiOx, wherein 0 < x < 2 ([0028];[0030]).
Sugimori teaches including a larger amount of silicon-containing material placed in the surface-side region rather than the current collector-side region. In working examples 5 – 6, Sugimori discloses including a content of silicon oxide-based active material in the second active material layer {i.e. surface-side sub layer 14c} that is three times greater than the content of silicon oxide-based active material in the first active material layer {i.e. collector-side sub layer 14b} (Table 1; [0068 – 0069];0071 – 0071]); therefore, Sugimori further discloses an electrode embodiment wherein the silicon oxide-based active materials in the first and second negative electrode active material layers is expressed by W2 = 3W1, which satisfies the Relational Equation 1: W2 > 2*W1, where W1 is a content of the silicon oxide-based active material in the first negative electrode active material layer and W2 is a content of the silicon oxide-based active material in the second negative electrode active material layer. Furthermore, in the embodiment of example 5 – 6, W1 is 2.5 wt%, which satisfies the claimed range of 0 < W1 ≤ 3 wt. %.
However, in examples 5 – 6, W2 is 7.5 wt% (Refer to Examples 5 – 6 in Table 1); therefore, Sugimori does not explicitly disclose an embodiment wherein the silicon-based active material in the second negative electrode active material layer satisfies 9 ≤ W2 ≤ 12 wt%.
Generally Sugimori teaches having a larger amount of silicon-containing material in the surface side region of the electrode {i.e. sub-layer 14c} than the current-collector side region of the electrode {i.e. sub-layer 14b} ([0033]). Sugimori further teaches having, in each negative electrode active material layer, the content of silicon-containing most preferably 1 to 20% by mass with respect to the total amount of negative electrode active material ([0032]). Sugimori further teaches that increasing the amount of silicon-containing material increases the influence of the expansion and contraction of the silicon-containing material and that decreases in the amount of silicon-containing active material decrease the increase capacity effect of the material ([0032]).
It would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to modify the content of the silicon-oxide based material in the second negative electrode active material of Sugimori’s example to be within the overlapping portion of Sugimori’s taught range and the claimed range, and thus obtain a negative electrode with active material layers having silicon-oxide bases oxide contents that satisfy the claimed relationship of 9 ≤ W2 ≤ 12 wt% to optimize the capacity of the battery while also minimizing the influence of the expansion and contraction of the silicon-containing material and achieving a higher content of silicon-containing active material in the surface side region of the electrode, with a reasonable expectation of success and without undue experimentation [MPEP 2144.05(II)]. Furthermore, by having a W2 within the claimed range, modified Sugimori, as established above, would still satisfy W2 > 2*W1.
The active material layers of Examples 5 – 6 further include graphite powder as the primary active material ([0068 – 0069];[0071 – 0072]).
Sugimori does not disclose the specific surface area of the active material in the embodiments; therefore, modified Sugimori does not explicitly disclose the second active material being a bimodal active material comprising active materials having different specific surface area.
Soma teaches a negative electrode active material including a first negative electrode active material layer on the collector and a second active material layer on the first negative electrode active material layer ([0014 – 0016]). The active material of both layers is taught by Soma to include primarily graphite, with the second active material further including low-crystalline carbon active material ([0018 – 0019]). Soma’s electrode configuration is taught to provide an electrode with high capacity and improved high-rate charge acceptance as well as cycle life performance ([0014]). The upper layer, by including the low-crystalline carbon, specifically improves the efficiency of the insertion and release of lithium ions that allows for high-rate discharge ([0018]). Soma additionally teaches that the electrode layers can further include silicon oxide active material ([0024]).
Since Sugimori teaches using graphite as the primary active material of their double-layer electrode embodiments ([0068 – 0069];[0071 – 0072]), and Soma teaches that, in a graphite-based double layer negative electrode it is beneficial to further include an additional, low-crystalline carbon in the second {i.e. upper} active material layer ([0018]), it would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to further include an additional low-crystalline carbon active material in the upper layer of Sugimori’s negative electrode, as taught by Soma, with a reasonable expectation of success in obtaining a double-layer negative electrode with improved lithium ion intercalation/deintercalation efficiency and high-rate discharge.
Modified Sugimori, as established above, includes two types of carbon active material {i.e. graphite and a low-crystalline carbon} as well as silicon active material in the second active material layer {i.e. 14c in Fig. 1 of Sugimori} (Sugimori: [0021];[0068 – 0073] and Soma: [0014];[0024]). The content of low-crystalline carbon is preferably 20% by mass or less of the active material layer contained in the upper layer (Soma: [0021]).
In order to further render obvious the claimed bimodal second active material configuration the following teachings are relied upon:
Lee teaches a negative electrode active material for a lithium secondary battery including, based on 100 parts by weight of the total negative electrode active material, 5 parts by weight to 20 parts by weight of a first carbon-based particle, 55 parts by weight to 90 parts by weight of a second carbon-based particle, and 1 part by weight to 40 parts by weight of a silicon-based particle ([0019]). Lee further teaches the specific surface area of the first carbon-based particle being 1.5 m2/g to 4.5 m2/g, the specific surface area of the second carbon-based particle is 0.4 m2/g to 1.5 m2/g ([0020]). As such Lee teaches a bimodal active material that includes carbon-based active materials having different specific surface areas as well as silicon active material. Lee further teaches that the first carbon-based particle and the second carbon-based particle may be respectively, for example, one or more selected from the group consisting of natural graphite, kish graphite, pyrolytic carbon, mesophase pitch-based carbon fiber, meso-carbon microbeads, mesophase pitches, soft carbon, hard carbon, non-graphitizable carbon, graphitizable carbon, petroleum coke and coal-based coke ([0035]) and therefore has a composition that overlaps in scope with the upper layer of modified Sugimori (Sugimori: [0021];[0068 – 0073] and Soma: [0015];[0018];[0024]) . Lee further teaches that the inclusion a first carbon-based particle having a relatively large specific surface area and a second carbon-based particle having a relatively small specific surface area counteracts the influence of large volume change of the silicon-based particle, imparts adhesion force to a negative electrode such that the negative electrode may exhibit appropriate adhesion force, and allows for the negative electrode active material to exhibit high initial efficiency, excellent high-rate charge and discharge properties, cycle properties, and swelling properties ([0026]).
Therefore, since the second active material layer of modified Sugimori has a composition within the scope of the active material taught by Lee {i.e. two types of carbon materials and silicon active material} and further teaches including the second type of carbon material in an amount of 20 wt% or less (Soma: [0021]), it would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, when modifying Sugimori to include a second carbon active material {i.e. the low-crystalline carbon}, to control the specific surface areas of two carbon materials in the active material layer as taught by Lee, with a reasonable expectation of success in counteracting the influence of large volume change of the silicon-based particles in the second active material layer and further in obtaining a negative electrode with high initial efficiency, excellent high-rate charge and discharge properties, cycle properties, and swelling properties.
By including a low-crystalline carbon active material with a specific surface area 1.5 m2/g to 4.5 m2/g (Soma: [0020] and Lee: [0019 – 0020]) and a graphite active material with a specific surface area of 0.4 m2/g to 1.5 m2/g (Soma: [0014] and Lee: [0019 – 0020]) in the second active material layer {i.e. 14c in Fig. 1 of Sugimori}, modified Sugimori includes the claimed bimodal second active material comprising active materials having different specific surface areas.
Modified Sugimori does not explicitly disclose a specific surface area (B2) of the second active material being larger than a specific surface area (B1) of the first active material.
Thomas-Aleya teaches forming, in negative electrodes with multiple active material layers, a particle specific surface area gradient where the surface area change, stepwise, with each layer ([0096];[0104];[0106]). Particularly Thomas-Aleya teaches having the back layer of the electrode {i.e. layer on the collector/first active material layer} include particles with a lower specific surface area and the front layer of the electrode {i.e. upper layer nearest to separator} include particles with a higher specific surface area ([0104 – 0106];[0108]). The change in specific surface area provides low resistances and high rate characteristics while minimizing side reactions and capacity losses ([0110 – 0111]). Thomas-Aleya further teaches that the active materials of such negative electrodes can include graphitic material ([0145]).
Since modified Sugimori also teaches a multi-layered electrode, it would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to control the specific surface areas of Sugimori’s first and second active material layers to have a stepwise specific surface area change, where the first layer {i.e. lower layer} has a smaller particle specific surface area than the second layer {i.e. upper layer}, as taught by Thomas-Aleya, and thus obtain the claimed active material layer specific surface area configuration, with a reasonable expectation of success in achieving a negative electrode with the benefits of minimized side reactions and capacity loss as well as low resistance and high rate characteristics.
As established above, modified Sugimori’s second active material layer includes two different carbon active materials and the materials have different specific surface areas, specifically, a low-crystalline carbon active material with a specific surface area of 1.5 m2/g to 4.5 m2/g (Soma: [0020] and Lee: [0019 – 0020]) and a graphite active material with a specific surface area of 0.4 m2/g to 1.5 m2/g (Soma: [0014] and Lee: [0019 – 0020]). One with ordinary skill in the art would recognize that, because modified Sugimori’s second active material layer contains two materials with different specific surface areas, the specific surface area (B2) of the second active material of modified Sugimori is necessarily an average specific surface area of the active material (2-1-th active material) having a large specific surface area and the active material (2-2-th active material) having a small specific surface area. One with ordinary skill in the art would further recognize that by being an active material mixture, modified Sugimori’s second active material is a homogeneous mixture including the 2-1-th active material and 2-2-th active material.
In addition, since modified Sugimori provides the claimed structure necessary to obtain the specific surface area in the manner claimed by the applicant {i.e. a mixed active material layer with two active materials having different specific surface areas}, the specific surface area of modified Sugimori’s second active material layer is capable of being obtained by adjusting the specific surface area of the 2-1-th active material, the specific surface area of the 2-2-th active material, and a mixing weight ratio between the 2-1-th active material and the 2-2-th active material. {Examiner Note: The recitation: -- and the specific surface area (B2) of the second active material is obtained by adjusting the specific surface area of the 2-1-th active material, the specific surface area of the 2-2-th active material, and a mixing weight ratio between the 2-1-th active material and the 2-2-th active material – is a product-by-process claim limitation that is not limited to the manipulations of the recited steps, only the structure implied by the steps}.
In modified Sugimori, the corresponding 2-1-th active material, present in an amount of 5 – 20 parts by weight based on 100 parts by weight of active material, is the low-crystalline carbon active material with a specific surface area of 1.5 m2/g to 4.5 m2/g (Soma: [0020 – 0021] and Lee: [0019 – 0020]) and the corresponding 2-2-th active material, present in an amount of 55 – 90 parts by weight of the active material, is the graphite active material with a specific surface area of 0.4 m2/g to 1.5 m2/g (Soma: [0014];[0021];[0024] and Lee: [0019 – 0020]). Furthermore, in modified Sugimori the 2-1-th active material and 2-2-th active material are mixed in a ratio {i.e. 2-1-th active material : 2-2-th active material} of 0.08:0.92 to 0.18:0.81 {i.e. based on parts by weight taught by Lee in [0019]}. Based on the taught ranges, in modified Sugimori the 2-2-th active material has a specific surface area of less than 100% of the specific surface area the 2-1-th active material ([0020]), which encompasses the claimed range of 40 – 90% and further, based on the mixing ratio of the two materials and the taught specific surface area ranges, modified Sugimori provides a specific surface area of the second active material (B2), of ≈ 0.5 m2/g to 2.02 m2/g which overlaps the claimed range 1.65 to 2.41 m2/g.
Lee further teaches that when the first carbon-based particle {i.e. corresponds to 2-1-th active material} has a specific surface area in the range of 1.5 m2/g to 4.5 m2/g , adhesion force may be imparted to a negative electrode due to a specific surface area of a predetermined level or more, and the initial irreversible capacity may be prevented from being excessively increased during charge and discharge due to the specific surface area ([0027]), and that when the second carbon-based particle {i.e. corresponds to 2-2-th active material} has a specific surface area of 0.4 m2/g to 1.5 m2/g, the initial irreversible capacity may be prevented from being excessively increased during charge and discharge ([0031]).
Thomas-Aleya further teaches higher specific surface area particles have lower volumetric charge transfer resistance and/or better charge transfer resistance per unit of specific surface area while lower specific surface area particles provide higher specific charge transfer resistance ([0110]). Thomas-Aleya further teaches that, while it is desirable to increase the overall specific surface area of an electrode active material to achieve low-resistance and high-rate characteristics, increases in particle specific surface areas can also lead to increased side reactions that cause losses in capacity and reduced battery safety ([0111]).
Therefore selection of specific surface areas and amounts for 2-1-th and 2-2-th active material that provide a ratio and second specific surface area {i.e. B2} within the overlapping portion of the ranges of modified Sugimori and the claimed ranges would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, in order to optimize the effects of the larger specific surface area active material {i.e. adhesion force of the active material layer (Lee: [0023];[0026 – 0027])} and the effects of the smaller specific surface area active material {i.e. allows for high-rate charge and discharge properties, cycle properties, and swelling properties (Lee: [0023];[0026];[0031])} while also preventing losses in capacity and reduced battery safety, with a reasonable expectation of success and without undue experimentation [MPEP 2144.05(II)].
Regarding Claims 4 – 5, modified Sugimori discloses all limitations as set forth above. As established above, modified Sugimori’s first active material layer has a specific surface area smaller than the second active material layer. The second active material provides a specific surface area (B2) of ≈ 0.5 m2/g to 2.02 m2/g (Refer to rejection of claim 1 above and Lee: [0019 – 0020]) and the minimum specific surface area of the first active material in modified Sugimori is 0.02 m2/g ([Thomas-Aleya: [0108]), as such modified Sugimori provides a specific surface area (B1) of the first active material that is ≈ 1% to less than 100% of the specific surface area (B2) of the second active material, which encompasses the claimed ranges 20 – 95% (Claim 4) and 40 – 95% (Claim 5).
Thomas-Aleya teaches that higher specific surface area particles have lower volumetric charge transfer resistance and/or better charge transfer resistance per unit of specific surface area while lower specific surface area particles result in higher specific charge transfer resistance ([0110]). Thomas-Aleya further teaches that, while it is desirable to increase the overall specific surface area of an electrode active material to achieve low-resistance and high-rate characteristics, increases in particles specific surface areas can also lead to increased side reactions that cause losses in capacity and reduced battery safety ([0111]).
Selection of specific surface areas for the first and second active materials that provide a ratio within the claimed range would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to optimize the effects {i.e. low resistance and high rate characteristics vs. increases in side reactions} caused by the larger specific surface area material layer and smaller specific surface area material layer, with a reasonable expectation of success and without undue experimentation [MPEP 2144.05(II)].
Regarding Claims 6 – 7, modified Sugimori discloses all limitations as set forth above. Sugimori teaches using graphite as the main active material of the first and second active material layers ([0068 – 0069];[0071 – 0072]). Sugimori generally teaches using, as the graphite, natural graphite, non-graphitizable carbon, and artificial graphite ([0032]).
Modified Sugimori does not particularly disclose in the embodiments wherein the first and second active materials are artificial graphite (Claims 6 and 7).
Thomas-Aleya teaches that a graphitized natural or synthetic material can serve as negative active materials ([0145]). Synthetic graphite is further taught by Thomas-Aleya to be suitable for active material layers that are included on {i.e. first active material layer} and away from the collector {i.e. second active material layer} ([0024 – 0025]).
Since Sugimori already teaches from a finite list of graphite materials using artificial graphite, it would have been obvious to one with ordinary skill in the art to specifically have the active material be artificial graphite, with a reasonable expectation of success that such a selection would be a suitable graphite active material for the negative electrode embodiments in Sugimori.
Regarding Claims 10 – 11, modified Sugimori discloses all limitations as set forth above. Sugimori further discloses wherein the first and second active material layers further comprise a binder, and the binder is a water soluble binder (Claim 10) and further wherein the binder comprises styrene-butadiene rubber, that is, in both active material layers in the example embodiments, Sugimori discloses the binder for the active material including styrene-butadiene rubber ([0068 – 0069];[0071 – 0072]), which is a water soluble binder material exemplified by the applicant (Instant Specification: [0040]).
Regarding Claim 13, modified Sugimori discloses all limitations as set forth above. Sugimori further discloses a secondary battery comprising: a positive electrode (Fig. 3, 13; [0044];[0061]); a separator interposed between the negative electrode and the positive electrode (Fig. 3, 15; [0049];[0061]); and an electrolyte ([0046 – 0048];[0061]).
Claim(s) 12 is rejected under 35 U.S.C. 103 as being unpatentable over Sugimori (US PG Pub. 2016/0351892 A1), Soma (JP2017062911A), Lee (US PG Pub. 2021/0202931 A1) and Thomas-Aleya (US PG Pub. 2012/0328942 A1), as applied to claim 1 above, and further in view of Lee (US PG. Pub. 2019/007740 A1 – cited in previous Office action mailed 09/04/2025). {Examiner Note: For the rejection of claim 12, the examiner has interpreted “wherein the negative electrode has a rolling density of 1.65 to 1.85 g/cc” to mean that the average rolling density of the negative electrode ranges from 1.65 to 1.85 g/cc.}
Regarding Claim 12, modified Sugimori discloses all limitations as set forth above. Sugimori teaches performing rolling, after applying and drying the active material layers, to manufacture their negative electrode and obtain a desired thickness ([0054 – 0056]).
Modified Sugimori does not disclose the rolling density of the negative electrode being 1.65 to 1.85 g/cc.
Lee teaches a multilayered negative electrode including a first negative electrode active material layer {i.e. layer on the collector} and a second negative electrode active material layer {i.e. layer on top of the first layer} ([0013 – 0014]). The negative electrode active materials utilized by Lee include carbon-based materials such as graphite ([0042]). Lee further teaches applying the active material layers with densities that provide an average electrode density of 1.2 g/cc or more ([0016];[0018]). When the average electrode density falls below 1.2 g/cc, Lee teaches that the adhesion, capacity maintenance rate, and output characteristics of the electrode decreases ([0019]). An average electrode density excessively above 1.2 g/cc {i.e. The highest average density Lee teaches is 1.85 g/cc, which is based on the additional ranges they include for the first and second active material layers in [0014]} indicates that one or both layers of active material have a density that is excessively high. Lee teaches the when the densities of the layers are too high the particle strength of the layers are too low and result in an overall reduction in electrolyte impregnability and ion diffusion for the electrode ([0017]). {Examiner Note: The densities taught by Lee are the densities after the active material layers are dried and rolled (Refer the preparation method disclosed in Lee’s example in [0083]; therefore, the examiner is interpreting the density taught by Lee to be the same as the claimed “rolling density”.}
It would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to have controlled modified Sugimori’s active material layers to have, after rolling, densities that provide an average rolling density of 1.22 g/cc or more, as taught by Lee, with a reasonable expectation of success in obtaining active material layers with high adhesion and increased output characteristics.
Selection of rolling densities that provide an average rolling density within the claimed range would have been obvious to one with ordinary skill in the art, before the effective filing date of the claimed invention, to achieve optimal adhesion, particle strength, and output characteristics for the electrode without reducing the electrolyte impregnability and ion diffusion capability of the electrode, with a reasonable expectation of success and without undue experimentation [MPEP 2144.05(II)].
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 ARYANA Y ORTIZ whose telephone number is (571)270-5986. The examiner can normally be reached M-F 7:00 AM - 5:00 PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
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.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/A.Y.O./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 8/13/2026
Prosecution Insights