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 .
Priority
Acknowledgment is made of applicant's claim for foreign priority based on an application filed in China on 12/10/2021. It is noted, however, that applicant has not filed a certified copy of the PCT/CN2021/137152 application as required by 37 CFR 1.55.
Status of Application
Claims 1-20 are pending. Claims 1-20 are presented for examination.
Claim Objections
1. Claim 20 is objected to because of the following informalities.
In claim 20, Ln 1, ”the battery pack of claim 24” appears to be a typographical error since there is no claim 24. For examination purposes, claim 20 is interpreted as being dependent from claim 19.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
2. The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
3. Claims 8-10, 12-13 and 16 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 8, in Ln 2-3, recites the limitation “the positive electrode sheet of each of the m battery cell sub-units has a coating weight smaller than that of the positive electrode sheet of each of the n battery cell sub-units”, which is indefinite because the claim does not define a coating weight of what substance(s), therefore, the metes and bounds of the claimed subject matter is unclear since any subject matter including but not limited to, active material, extra metal layer, ion conductive layer or adhesive layer etc. could be a coating subject. It is further unclear about the metes and bounds of the relative term “a coating weight smaller than that of” because a skilled artisan would not be able to figure out what the relative term “smaller than” means since the claim language does not define the coating substance(s). The recited limitation also causes problems when comparing to relevant prior art due to its indefiniteness. Claims must be provided with their broadest reasonable interpretation in light of the specification, however, limitations from the specification must not be read into the claims (MPEP 2111). Since the recitation “a coating weight” is not defined in the claim regarding what substance is the coating, the term will be interpreted under its broadest reasonable interpretation (BRI) such as any kind of substance(s) or combination of substance(s) in any form of coating would read thereon, even though the specification in paragraph [00143] seems referring to the coating weight of the active material layers.
Claims 9 and 10, dependent from claim 8, are rejected for incorporating the same indefiniteness from their base claim, respectively.
Claim 9 has the same issue of indefiniteness regarding the term “a coating weight smaller than that of” being used in the claim in Ln 4-5, thus is rejected for the same reason as set forth above.
Claim 10, further in Ln 1 and Ln 2-3 respectively, recites “The battery cell of claim 8, wherein the coating weight of the negative electrode sheet” and “the coating weight of the negative electrode sheet” is indefinite because there is insufficient antecedent basis for “the coating weight of the negative electrode sheet” in the claim or its base claim 8. For examination purposes, the claim is interpreted as being dependent from claim 9 which recites “the negative electrode sheet of each of the m battery cell sub-units has a coating weight”.
Claim 12 in Ln1-4 and Claim 13 in Ln 1-4 recites “the content of the binder in the positive/negative electrode sheet of the m battery cell sub-units is 3% by weight to 4% by weight, and the content of the binder in the positive (claim 12)/negative (claim 13) electrode sheet of each of the n battery cell sub-units is 1% by weight to 2% by weight”. There is no definition in the claim as to the percentage of weight is based on what as a total of 100% by weight. The weight percentage number is indefinite because it can be based on the total weigh of: the whole positive/negative electrode sheet, the weight of the active material layer of the positive/negative electrode, or anything else for constructing the positive/negative electrode sheet (e.g., polymer and additives, nonelectrochemical active material). Therefore, the metes and bounds of the numerical ranges of “3% by weight to 4% by weight” and “1% by weight to 2% by weight” cannot be determined. For examination purposes, all the weight percentages in the claim are interpreted under its BRI as based on 1) the total weight of the whole positive/negative electrode sheet including positive/negative electrode current collector (support layer and metal layer) and all substances being coated or loaded on the positive/negative electrode current collector; 2) the total weight of the active material layer of the positive/negative electrode; or 3) the total weight of anything else for constructing the positive/negative electrode sheet.
Claim 16, in Ln 1-2, recites “the compaction density of the negative electrode sheet” is indefinite because there is insufficient antecedent basis for it in the claim or its base claim 14. For examination purposes, the claim is interpreted as being dependent from claim 15 which recites “the negative electrode sheet of each of the m battery cell sub-units has a compaction density…”.
Claim Rejections - 35 USC § 102
4. In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
5. The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
6. This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
7. Claims 1-2 and 19 are rejected under 35 U.S.C. 102 (a)(1) as being anticipated by Hasegawa (US 20180316065 A1, IDS of 4/29/2025).
Regarding claim 1, Hasegawa discloses a battery cell (stacked battery 100, [0042] and FIG. 1), comprising an intermediate portion (10H, FIG. 1) and side portions (10A/10B and 10N, FIG. 1) located on two sides of the intermediate portion (center-side cell, [0070]) in a thickness direction (FIG. 1), the intermediate portion (10H, FIG. 1) comprising m battery cell sub-units and the side portions (10A+10B and 10N, FIG. 1) comprising n battery cell sub-units, m+n being an integer greater than or equal to 3 (battery cells 10A, 10B to 10H 10N, FIG. 1), wherein each of the battery cell sub-units comprises a positive electrode sheet (1 and 4, [0114] and [0117] and FIG.1), a negative electrode sheet (2 and 5, [0115] and [0118] and FIG. 1) and a separator (3 solid electrolyte layer, [0116] and FIG. 1) arranged between the positive electrode sheet and the negative electrode sheet (FIG. 1), and each of the m battery cell sub-units has a dry battery cell nail penetration short-circuit resistance greater than that of each of the n battery cell sub-units (P2> P1 and P2>P3 in FIG. 3; and 20th-50th cells vs. 10th and 60th cells in Table 2) .
Regarding claim 2, Hasegawa discloses all of the limitations as set forth above. Hasegawa further discloses the center-side cell belongs to a cell region including a ((N/3)+1)th cell to a (2N/3)th cell ([0070]), which means the intermediate portion (center-side cell) has about N/3 of the cells, therefore, in light of the thickness of the cells are about the same shown in FIG. 1, a skilled artisan would reasonably envisage the thickness of the intermediate portion would be about 33% of the total thickness of the battery cell falling within the range of 20% to 40% as claimed “a thickness accounting for 20% to 40% of a total thickness of the battery cell”.
Regarding claim 19, Hasegawa discloses all of the limitations as set forth above. Hasegawa further discloses a battery pack (an exterior package, [0069]), comprising the battery cell of claim 1.
Claim Rejections - 35 USC § 103
8. 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.
9. The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
10. Claims 3-7 are rejected under 35 U.S.C. 103 as being unpatentable over Hasegawa (US 20180316065 A1, IDS of 4/29/2025), in view of Shen (US 20160006013 A1).
Regarding claim 3, Hasegawa discloses all of the limitations as set forth above. Hasegawa discloses the positive electrode sheet comprises a positive electrode current collector (4, [0117] and FIG. 1).
Hasegawa discloses the deterioration of the battery material resulting from the temperature of the cell increases because when a cell with low short circuit resistance and a cell with high short circuit resistance are mixed, a current flows from the cell with high short circuit resistance to the cell with low short circuit resistance ([0008]).
However, Hasegawa does not explicitly disclose the positive electrode current collector comprising a support layer and a metal layer, and the support layer of the positive electrode current collector of each of the m battery cell sub-units has a thickness greater than that of the support layer of the positive electrode current collector of each of the n battery cell sub-units.
Shen teaches the same problem of short circuit producing a lot of heat damaging the battery or harm the users, reducing safety and reliability of the power battery ([0009]). To solve the problem, Shen teaches a battery comprising three cores 4, 5, 6 with a protection component 2 and a protection component 3 disposed between the cores and the shell 1 ([0034] and FIG. 1) and each of the protection component 2 or 3 includes two insulating layers 22 or 32 and a conducting layer 21 or 31 disposed between the two insulating layers 22 or 32 ([0025] [0035] and FIG. 1). Shen further teaches the conducting layer 21 of the protection component 2 is connected to the positive electrode tab 41 ([0037] and FIG. 1). Since the protection component 2 is essentially collecting current of the positive electrode through the positive tab 41, in which the insulating layer 22 corresponding to a support layer in the claim, and the conducting layer 21 corresponding to a metal layer in the claim. Therefore, the protection component 2 of Shen functions substantially equivalent to the claimed “the positive electrode current collector comprising a support layer and a metal layer”.
It would have been obvious to a skilled artisan before the effective filing date of the claimed invention to modify the positive electrode current collector 4 of Hasegawa with an addition of a support layer in the same fashion as the insulating layer 22 being attached to the conducting layer 21 taught by Shen, thus arriving at the claimed “the positive electrode current collector comprising a support layer and a metal layer”, in order to mitigate the deterioration of the battery material resulting from the temperature of the cell increases.
Modified Hasegawa further discloses an equivalent circuit ([0036] FIG. 4) explaining a sneak current I flowing from the cell with high short circuit resistance 10H to the cell with low short circuit resistance 10A (R10H>R10A, FIG. 3); and the current collecting tabs with a different tab resistance (RTA or RTH, FIG. 4) which may be adjustable by the properties of the current collecting tab, a shape of the current collecting tab, a placement of a resistor, and a welding condition ([0056]).
However, modified Hasegawa does not explicitly disclose that the support layer of the positive electrode current collector of each of the m battery cell sub-units has a thickness greater than that of the support layer of the positive electrode current collector of each of the n battery cell sub-units.
Shen further teaches that a first heat produced by the short circuit between the positive and negative electrode materials is the maximum, about two or even three times of that of the second heat which is minimum produced by the short circuit between the positive and negative electrode current collectors ([0042]). In modified Hasegawa, a skilled artisan would reasonably envisage the first heat, the major heat source produced by the short circuit between the positive and negative electrode materials of the m battery cell sub-units of the intermediate portion would be much harder to dissipate because theses cell sub-units are located in the middle portion of the battery stack. Therefore, in order to avoid temperature increasing too fast among the m battery cell sub-units of the intermediate portion, a skilled artisan would reasonably envisage the need of directing some current flowing from the intermediate portion m battery cell sub-units to the side portions n battery cell sub-units, taught by Hasegawa FIG. 4, the sneak current flows from the cell with high short circuit resistance 10H to the cell with low short circuit resistance 10A.
It would have been obvious to a skilled artisan to prepare the thickness of the support layer of the positive electrode current collector of each of the m battery cell sub-units to be greater than that of the support layer of the positive electrode current collector of each of the n battery cell sub-units, such that the tab resistance of RTH would be higher than that of RTA, in order to direct some current flow from the intermediate portion 10H towards the side portion 10A, as taught by Hasegawa FIG. 4, arriving at the claimed “the support layer of the positive electrode current collector of each of the m battery cell sub-units has a thickness greater than that of the support layer of the positive electrode current collector of each of the n battery cell sub-units”, so as to mitigate a potential rapid temperature increase in the intermediate portion of the stacked battery of modified Hasegawa due to the difficulty to dissipate first heat generated at the location in the middle of the stacked battery.
Regarding claim 4, modified Hasegawa discloses all of the limitations as set forth above. Modified Hasegawa does not explicitly disclose the metal layer of the positive electrode current collector of each of the m battery cell sub-units has a resistivity greater than that of the metal layer of the positive electrode current collector of each of the n battery cell sub-units.
Since in modified Hasegawa the conducting layer and the electrode tab are made of the same metal (Hasegawa: FIG. 2; and Shen: [0040]), the tab resistance (RTA or RTH, FIG. 4) shown in Hasegawa FIG. 4 represents the metal layer’s (conducting layer 21) resistance.
As established above in claim 3, Hasegawa mentions the tab resistance is adjustable by the properties of the current collecting tab ([0056]), it would have been obvious to a skilled artisan before the effective filing date of the claimed invention to make the metal layer of the positive electrode current collector of each of the m battery cell sub-units has a resistivity greater than that of the metal layer of the positive electrode current collector of each of the n battery cell sub-units as claimed, in order to successfully direct some current flow from the intermediate portion 10H towards the side portion 10A, mitigating a potential rapid temperature increase in the intermediate portion of the stacked battery of modified Hasegawa due to the difficulty to dissipate first heat generated at the location in the middle of the stacked battery.
Regarding claim 5, modified Hasegawa discloses all of the limitations as set forth above. Modified Hasegawa does not explicitly disclose the resistivity of the metal layer of the positive electrode current collector of each of the m battery cell sub-units is 1.05 to 1.5 times the resistivity of the metal layer of the positive electrode current collector of each of the n battery cell sub-units.
However, modified Hasegawa does disclose the material of the current collecting tab differs, the specific resistance also differs ([0057]), and in Table 1 that the specific resistance data for materials used for the current collecting tab, including SUS with 72x10-6 Ω·cm and Ti with 55x10-6 Ω·cm among other choices (Table 1). It would have been obvious to a skilled artisan before the effective filing date of the claimed invention to choose SUS for the metal layer of the positive electrode current collector of each of the m battery cell sub-units and Ti for the metal layer of the positive electrode current collector of each of the n battery cell sub-units from the finite choices listed in Table 1, in order to have a higher resistance for the m battery cell sub-units in the intermediate portion. Thus the resistivity ratio of SUS to Ti is calculated to be 1.3, falling within the range of 1.05 to 1.5 as claimed “the resistivity of the metal layer of the positive electrode current collector of each of the m battery cell sub-units is 1.05 to 1.5 times the resistivity of the metal layer of the positive electrode current collector of each of the n battery cell sub-units”.
Regarding claim 6, modified Hasegawa discloses all of the limitations as set forth above. Modified Hasegawa does not explicitly disclose the metal layer of the positive electrode current collector of each of the m battery cell sub- units has a thickness smaller than that of the metal layer of the positive electrode current collector of each of the n battery cell sub-units.
Modified Hasegawa has the conducting layer and the electrode tab made of the same metal (Hasegawa: FIG. 2; and Shen: [0040]), the tab resistance (RTA or RTH, FIG. 4) shown in Hasegawa FIG. 4 represents the metal layer (conducting layer 21) resistance. Further, as established above in claim 3, the tab resistance is adjustable by the properties of the current collecting tab ([0056]), and the need exists to direct some current from the m battery cell sub-units of the intermediate portion to the n battery cell sub-units of the side portions.
Modified Hasegawa further discloses when the thickness of the current collecting tab is larger, the resistance of the current collecting tab tends to be lower ([0059]). Therefore, it would have been obvious to a skilled artisan before the effective filing date of the claimed invention to make the metal layer of the positive electrode current collector of each of the m battery cell sub- units has a thickness smaller than that of the metal layer of the positive electrode current collector of each of the n battery cell sub-units as claimed, such as to make the resistance of the m battery cell sub-units of the intermediate portion relatively higher than that of the n battery cell sub-units of the side portions, in order to mitigate a potential rapid temperature increase in the intermediate portion of the stacked battery of modified Hasegawa due to the difficulty to dissipate first heat generated at the location in the middle of the stacked battery.
Regarding claim 7, modified Hasegawa discloses all of the limitations as set forth above. While modified Hasegawa further discloses the thickness of the cathode current collecting tabs may be different for the surface -side and the center-side cells ([0060]) and the thickness difference is for example, 30 µm or more, and may be 200 µm or more ([0059]) and the resistance ratio of cathode current collecting tab for cells in the surface-side to cells in the center-side is for example 1.1 ([0055] [0071]), modified Hasegawa does not explicitly disclose the thickness of the metal layer of the positive electrode current collector of each of the m battery cell sub-units is 60% to 90% of the thickness of the metal layer of the positive electrode current collector of each of the n battery cell sub-units.
However, since resistance of a metal is inversely proportional to the cross-sectional area (A) of a conductor given by R=ρ(L/A) and the thickness (area) decreases the resistance increases proportionally, the resistance ratio of cathode current collecting tab for cells at different region being 1.1 ([0071]) translates to the thickness ratio of the positive current collecting metal layers at different region is 1.1.
Further, as established in claim 6, the metal layer of the positive electrode current collector of each of the m battery cell sub- units has a thickness smaller than that of the metal layer of the positive electrode current collector of each of the n battery cell sub-units, a skilled artisan would reasonably make the thickness ratio of the forgoing m battery cell sub-units to the n battery cell sub-units to be 1:1.1, equivalent to about 90% in the thickness ratio of the metal layers in the two regions, arriving at the higher end of the range as claimed “the thickness of the metal layer of the positive electrode current collector of each of the m battery cell sub-units is 60% to 90% of the thickness of the metal layer of the positive electrode current collector of each of the n battery cell sub-units”.
11. Claims 8-18 are rejected under 35 U.S.C. 103 as being unpatentable over Hasegawa (US 20180316065 A1, IDS of 4/29/2025).
Regarding claims 8 and 9, in light of the 112 (b) rejection as set forth above, Hasegawa discloses all of the limitations as set forth above. Hasegawa discloses the deterioration of the battery material resulting from the temperature of the cell increases ([0008]), and an equivalent circuit explaining a sneak current I flowing due to unevenness of short circuit resistance ([0036] and FIG. 4).
Hasegawa does not explicitly disclose that: the positive electrode sheet of each of the m battery cell sub-units has a coating weight smaller than that of the positive electrode sheet of each of the n battery cell sub-units (claim 8); nor
the coating weight of the positive electrode sheet of each of the m battery cell sub-units is 70% to 90% of the coating weight of the positive electrode sheet of each of the n battery cell sub-units; and/or the negative electrode sheet of each of the m battery cell sub-units has a coating weight smaller than that of the negative electrode sheet of each of the n battery cell sub-units (claim 9).
However, it is well-known that the heat generated by the m battery cell sub-units of the intermediate portion would be much harder to dissipates due to the location being in the middle portion of the battery stack; and the coating weight (or loading ) of an active material layer on an electrode is generally proportional to the heat generated during operation of a cell. A skilled artisan would reasonably envisage reducing the coating weight of an electrode active material layer for the cells located in the intermediate portion of the cell stack of Hasegawa in order to reduce the amount of heat generated in the intermediate portion, avoiding the temperature increasing too fast among the m battery cell sub-units of the intermediate portion of Hasegawa.
Therefore, it would have been obvious to a skilled artisan before the effective filing date of the claimed invention to make the positive electrode sheet of each of the m battery cell sub-units has a coating weight smaller than that of the positive electrode sheet of each of the n battery cell sub-units (claim 8), in order to achieve an overall balanced heat distribution among the battery cells for mitigating the deterioration of the battery material resulting from the temperature of the cell increases.
It would have been further obvious to a skilled artisan before the effective filing date of the claimed invention to make the negative electrode sheet of each of the m battery cell sub-units has a coating weight smaller than that of the negative electrode sheet of each of the n battery cell sub-units (claim 9), in order to achieve an overall balanced heat distribution among the battery cells for mitigating the deterioration of the battery material resulting from the temperature of the cell increases.
Regarding claim 10, in light of the 112 (b) rejection as set forth above, modified Hasegawa discloses all of the limitations as set forth above. Hasegawa does not explicitly disclose the coating weight of the negative electrode sheet of each of the m battery cell sub-units is 70% to 90% of the coating weight of the negative electrode sheet of each of the n battery cell sub-units.
However, Hasegawa further discloses the thickness of the anode active material layer varies within a range of 0.1 µm to 300 µm, and may be within a range of 0.1 µm to 100 µm ([0084]); and the proportion of the anode active material may be within a range of 60% by weight to 99% by weight ([0078]). A skilled artisan would adjust within the taught active material range (60-99 weight% ) for the m battery cell sub-unit with routine experimentation in order to ensure the active material coating weight for the m battery cell sub-unit is less than that of the n battery cell sub-units for reducing heat generation in the intermediate portion of the stacked battery as well as to balance with an optimized overall capacity of the battery cell, with a reasonable expectation in arriving at an optimized negative electrode sheet coating weight value for the m battery cell sub-units that falls within the range of 70% to 90% of the coating weight for the side battery portion as claimed “the coating weight of the negative electrode sheet of each of the m battery cell sub-units is 70% to 90% of the coating weight of the negative electrode sheet of each of the n battery cell sub-units”.
Regarding claims 11 and 12, in light of the 112 (b) rejection to claim 12 as set forth above, Hasegawa discloses all of the limitations as set forth above. Hasegawa discloses the deterioration of the battery material resulting from the temperature of the cell increases ([0008]), and an equivalent circuit explaining a sneak current I flowing due to unevenness of short circuit resistance ([0036] and FIG. 4).
Hasegawa does not explicitly disclose that a binder in the positive electrode sheet of each of the m battery cell sub-units has a content greater than that of a binder in the positive electrode sheet of each of the n battery cell sub-units (claim 11); nor
the content of the binder in the positive electrode sheet of each of the m battery cell sub-units is 3% by weight to 4% by weight, and the content of the binder in the positive electrode sheet of each of the n battery cell sub-units is 1% by weight to 2% by weight; and/or a binder in the negative electrode sheet of each of the m battery cell sub-units has a content greater than that of a binder in the negative electrode sheet of each of the n battery cell sub-units (claim 12).
However, it is well-known that the heat generated by the m battery cell sub-units of the intermediate portion would be much harder to dissipates due to the location is in the middle portion of the battery stack, and the binder content in an electrode is generally inversely proportional to the active material loading in the active material layer, thus inversely proportional to the heat generated during operation of a cell and also increase resistance.
Therefore, a skilled artisan would have found it obvious before the effective filing date of the claimed invention, to increase the content of a binder in the positive electrode sheet for the m battery cell sub-units located in the intermediate portion of the cell stack of Hasegawa in order to reduce the first heat generated in the intermediate portion avoiding the temperature increase too fast among the m battery cell sub-units of the intermediate portion and increase the internal resistance of the m battery cell sub-units of the intermediate portion in order to have some current flowing from m battery cell sub-units of the intermediate portion to n battery cell sub-units at the side portions.
It would have been obvious before the effective filing date of the claimed invention, to arrive at the claimed “a binder in the positive electrode sheet of each of the m battery cell sub-units has a content greater than that of a binder in the positive electrode sheet of each of the n battery cell sub-units” (claim 11); or “a binder in the negative electrode sheet of each of the m battery cell sub-units has a content greater than that of a binder in the negative electrode sheet of each of the n battery cell sub-units” (claim 12), in order to manage heat generated in the intermediate portion and maintain an overall balanced heat distribution among the battery cells for mitigating the deterioration of the battery material resulting from the temperature of the cell increases.
Regarding claim 13, in light of the 112 (b) rejection as set forth above, modified Hasegawa discloses all of the limitations as set forth above. While modified Hasegawa further discloses anode active material: sulfide solid electrolyte material: conductive material: binder =55:42:2:1 which means the binder in n battery cell sub-units the negative electrode sheet is 1% by weight to the total weight of the negative electrode.
However, modified Hasegawa does not explicitly disclose the content of the binder in the negative electrode sheet is of each of the m battery cell sub-units is 3% by weight to 4% by weight.
However, as established above in claim 12, the binder content in the m battery cell sub-units is modified to be higher than that in the n battery cell sub-units, it would have been obvious to a skilled artisan to further adjust the binder content through routine experimentation in order to achieve an optimized balance between a reduced the temperature increase among the m battery cell sub-units of the intermediate portion and a desired overall capacity of the battery cell, and with a reasonable expectation to achieve a success binder content value for each of the m battery cell sub-units that falls within in the range of 3% by weight to 4% by weight as claimed “the content of the binder in the negative electrode sheet is of each of the m battery cell sub-units is 3% by weight to 4% by weight”.
Regarding claims 14 and 15, Hasegawa discloses all of the limitations as set forth above. While Hasegawa discloses the deterioration of the battery material resulting from the temperature of the cell increases ([0008]), and an equivalent circuit explaining a sneak current I flowing due to unevenness of short circuit resistance ([0036] and FIG. 4), Hasegawa does not explicitly disclose that the positive electrode sheet of each of the m battery cell sub-units has a compaction density smaller than that of the positive electrode sheet of each of the n battery cell sub-units (claim 14); nor the compaction density of the positive electrode sheet of each of the m battery cell sub-units is 80% to 98% of the compaction density of the positive electrode sheet of each of the n battery cell sub-units; and/or the negative electrode sheet of each of the m battery cell sub-units has a compaction density smaller than that of the negative electrode sheet of each of the n battery cell sub-units (claim 15).
Since it is well-known that the heat generated by the m battery cell sub-units of the intermediate portion would be much harder to dissipates due to the location is in the middle portion of the battery stack, and the compact density of an electrode is generally proportional to energy density, thus proportional to the heat generated during operation of a cell, a skilled artisan would reasonably envisage reducing the compact density in order to reduce heat generated in the intermediate portion avoiding the temperature increase too fast among the m battery cell sub-units of the intermediate portion of Hasegawa either in the positive electrode sheet or in the negative electrode sheet for the m battery cells located in the intermediate portion of the cell stack .
Therefore, it would have been obvious to a skilled artisan before the effective filing date of the claimed invention to make the positive electrode sheet (claim 14) or the negative electrode sheet (claim 15) of each of the m battery cell sub-units has a compaction density smaller than that of the positive electrode sheet of each of the n battery cell sub-units, in order to achieve an overall balanced heat distribution among the battery cells for mitigating the deterioration of the battery material resulting from the temperature of the cell increases.
Regarding claim 16, in light of the 112 (b) rejection as set forth above, modified Hasegawa discloses all of the limitations as set forth above. Modified Hasegawa does not explicitly disclose the compaction density of the negative electrode sheet of each of the m battery cell sub-units is 80% to 98% of the compaction density of the negative electrode sheet of each of the n battery cell sub-units.
However, as established above, compaction density is proportional to the heat generated during operation of a cell, rendering obvious reducing compaction density of the negative electrode sheet of the m battery cell sub-units would reasonably reduce the heat generated in the intermediate portion thus avoiding temperature increasing too fast among the m battery cell sub-units of the intermediate portion of Hasegawa’s stacked cell.
Further, Hasegawa teaches the average particle size (D50) of the anode active material is for example, within a range of 10 nm to 50 µm, and may be within a range of 100 nm to 20 µm; and the proportion of the anode active material in the anode active material layer is for example, 50% by weight or more, and may be within a range of 60% by weight to 99% by weight ([0078]). A skilled artisan would reasonably expect through routine optimizations of average particle sizes and the weight% of the anode active material in the anode of the m battery cell units within taught ranges would result in a relative compact density value for m battery cell sub-units that falls within 80% to 98% of that of n battery cell sub-units, with a successful balance between reducing the amount of heat generated in the m battery cell of the intermediate portion and achieving an optimized overall capacity of the battery cell, thus arriving at the claimed “the negative electrode sheet of each of the m battery cell sub-units that has 80% to 98% of the compact density of the negative electrode sheet of each of the n battery cell sub-units”.
Regarding claim 17, Hasegawa discloses all of the limitations as set forth above. While Hasegawa discloses the deterioration of the battery material resulting from the temperature of the cell increases ([0008]), and an equivalent circuit explaining a sneak current I flowing due to unevenness of short circuit resistance ([0036] and FIG. 4), Hasegawa does not explicitly disclose that the separator of each of the m battery cell sub-units has a thickness greater than that of the separator of each of the n battery cell sub-units.
However, it is well-known that the heat generated by the m battery cell sub-units of the intermediate portion would be much harder to dissipates due to the location being in the middle portion of the battery stack; and the thickness of a separator of a cell is generally proportional to the internal resistance of a cell. A skilled artisan would reasonably envisage before the effective filing date of the claimed invention, increasing the thickness of the separator for the cells located in the intermediate portion of the cell stack of Hasegawa to direct some current flowing from the m battery cell sub-units of the intermediate portion to the n battery cell sub-units of the side portions via making the internal resistance rH of the m battery cell sub-units of the intermediate portion relatively higher than the internal resistance rA of the n battery cell sub-units of the side portions, in order to mitigate temperature increasing too fast among the m battery cell sub-units of the intermediate portion due to the difficulty to dissipate the huge generated heat in the stacked battery of modified Hasegawa.
It would have been obvious to a skilled artisan before the effective filing date of the claimed invention to make the separator of each of the m battery cell sub-units has a thickness greater than that of the separator of each of the n battery cell sub-units as claimed, thus making the internal resistance of the m battery cell sub-units of the intermediate portion relatively higher than that of the n battery cell sub-units of the side portions, in order to mitigate the deterioration of the battery material resulting from the temperature of the cell increases.
Regarding claim 18, modified Hasegawa discloses all of the limitations as set forth above. Modified Hasegawa does not explicitly disclose the thickness of the separator of each of the m battery cell sub-units is 10 to 13 µm, and the thickness of the separator of each of the n battery cell sub- units is 7 to 9 µm.
However, modified Hasegawa further discloses the thickness of the separator (solid electrolyte layer 3, [0042] FIG. 1) within a range of 0.1 µm to 100 µm ([0090]), encompassing the claimed thickness ranges for both the m battery cell sub-units (10 to 13 µm) and the n battery cell sub-units (7 to 9 µm). A skilled artisan would expect to further optimize the thickness of the separator within the taught range under routine experimentation, which would reasonable result in values falling within the thickness ranges combination as claimed “the thickness of the separator of each of the m battery cell sub-units is 10 to 13 µm, and the thickness of the separator of each of the n battery cell sub- units is 7 to 9 µm”, with a success in achieving an optimized balance between battery cycling characteristics and mitigating the deterioration of the battery material resulting from the temperature of the cell increases.
12. Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Hasegawa (US 20180316065 A1, IDS of 4/29/2025) in view of Watanabe (US 20190245190 A1).
Regarding claim 20, Hasegawa discloses all of the limitations as set forth above. Hasegawa dos not explicitly discloses an electrical apparatus, comprising the battery pack, wherein the battery pack is used as a power source or an energy storage unit of the electrical apparatus.
Watanabe, in the same field of endeavor teaches a stacked battery pack (FIG. 3) used as a power source ([0095]). It would have been obvious to a skilled artisan before the effective filing date of claimed invention to use the Hasegawa’s battery pack as a power source as taught by Watanabe.
Conclusion
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/K. L./Examiner, Art Unit 1751 3/3/2026
/Haroon S. Sheikh/Primary Examiner, Art Unit 1751