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
Applicant's arguments filed July 13, 2026, have been fully considered but they are not persuasive. Based on applicant’s amendments the rejection below has been updated to address the amendments.
Applicant argues that neither Kudo nor Ueki teaches or suggests the claimed relationship requiring that the average thickness of the porous coating layer be greater than the average particle diameter of the lithium transition metal oxide particles.
The argument has been considered but is not persuasive.
Ueki expressly teaches that the average thickness T of the porous filler layer is intentionally selected to be greater than the average particle diameter D of the positive electrode active material and repeatedly explains that its dimensional relationship suppresses penetration of active material into the coating layer and prevents leakage current after separator melting. Ueki further provides comparative experimental data demonstrating that batteries satisfying T>D suppress leakage current, whereas batteries having T<D exhibit leakage current due to penetration of the active material through the coating layer.
Applicant further argues that Ueki is directed to a battery pack subjected to retaining pressure and therefor addresses a different problem.
The argument has been considered but is not persuasive.
Although Ueki discusses battery packs employing retaining pressure, the reference expressly teaches that the relationship between coating thickness and active material particle diameter provides the short-circuit suppression mechanism. The dimensional relationship is described as a structural characteristic of the coated separator itself and is not limited to any particular battery pack configuration. The reference repeatedly explains that the leakage-current suppression results from the coating thickness exceeding the active material particle diameter, making the teaching directly applicable to coated separators such as those disclosed by Kudo.
Applicant additionally argues that there is no motivation to combine the references.
The argument has been considered but is not persuasive.
Kudo is directed to coated separators for improving battery safety and separator durability. Ueki is likewise directed to coated separators for lithium secondary batteries and teaches optimization of the coating thickness relative to active material particle size to further improve thermal safety and suppress leakage current. Because both references address the same type of separator structure for the same class of lithium secondary batteries and seek to improve battery safety and reliability, one of ordinary skill in the art would have been motivated to incorporate Ueki’s dimensional optimization into Kudo’s coated separator with a reasonable expectation of obtaining the predictable improvements expressly described by Ueki.
Applicant has not provided objective evidence demonstrating that the claimed dimensional relationship produces results unexpected over the combined teachings of Kudo and Ueki. Rather, Ueki itself teaches that the claimed relationship produces results unexpected over the combined teachings of Kudo and Ueki. Rather, Ueki itself teaches that the claimed relationship produces the very benefits relied upon by Applicant. Therefore, the evidence of record supports the conclusion that the claimed subject matter would have been obvious to one of ordinary skill in the art at the time of the invention.
Claim Objections
Claim 2 has been amended to overcome the objection. Accordingly, the objection to claim 2 is withdrawn.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-14 are rejected under 35 U.S.C. 103 as being unpatentable over Kudo, Hisanori et al. (JP 2021044131 A), hereinafter Kudo, in further view of Ueki, Tomoyoshi (US 20140193691 A1), hereinafter Ueki.
Regarding claim 1, Kudo teaches an energy storage device ([0016]), comprising:
An electrode assembly with a positive electrode and negative electrode are stacked with separator in between ([0041], negative electrode 20, positive electrode 30, separator 50);
An electrolyte solution ([0033]);
A case which houses ([0034], Fig. 1, battery case 10):
The electrode assembly ([0032]);
The electrolyte solution ([0032-0034]);
The electrode assembly is in a state where a load is applied ([0032-0034]):
A pressure P0 (MPa) applied to the electrode assembly in a discharge state ([0035]).
Additionally, Kudo teaches the separator is made of polyethylene-based resin ([0040]).
Kudo fails to teach the pressure applied to the electrode assembly; a strain A obtained when separator is compressed in a thickness direction under an environment of 45 °C at a pressure of MPa satisfy the following Formula 1: P0 (1-A) < 1.2 MPa.
Ueki teaches applying pressure to an electrode assembly, wherein the applied pressure is greater than 0.1 MPa ([0010]). Ueki further teaches a nonaqueous electrolyte secondary battery including a separator having a porous coating layer containing inorganic particles and binder, wherein the average thickness T of the porous coating layer is greater than the average particle diameter D of the positive electrode active material (T>D) ([0013], . Ueki explains that when the coating thickness exceeds the active material particles diameter, penetration of the active material through the coating layer during separator melting is prevented, thereby suppressing leakage current and preventing internal short circuiting. Ueki further teaches through Examples 1-3 and Comparative Examples 1-2 that batteries satisfying T>D exhibit improved safety and suppression of leakage current, whereas batteries having T<D do not.
Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to modify the electrode assembly of Kudo to include the pressure conditions taught by Ueki, and to have a porous coating layer thickness greater than the average particle diameter of the lithium transition metal oxide particles as taught by Ueki in order to improve separator reliability, suppress leakage current, improve resistance to internal short circuiting during elevated temperature events, and improve overall battery safety. The claimed limitation requiring that the electrode assembly is in a state where a load is applied including a pressure P0 applied in a discharge state, is therefore taught or suggested by the combination of Kudo and Ueki. Applying the dimensional relationship taught by Ueki to the coated separator of Kudo merely represents the predictable use of a known technique to improve a similar device in the same field of endeavor.
With respect to the limitation that a strain A obtained when the separator is compressed under specified conditions (45 °C and pressure) satisfies the recited formula 1: P0 (1-A) < 1.2 MPa. This limitation is directed to a stress-strain relationship, which is an inherent physical property of the material system (the polyethylene-based separator under applied pressure and temperature conditions). Because Kudo teaches the same separator material and structure, and Ueki teaches applying pressure within an overlapping range, the resulting stress-strain behavior would have been obtainable through routine optimization of known variables (pressure and temperature).
Regarding claim 2, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo fails to teach the difference between pressure P0 and pressure applied P1 to the electrode assembly in a charge state of 0.9 MPa or less. However, Kudo ([0042]) and Ueki (0010]) teach controlling applied pressure to electrode assemblies within defined ranges. Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to control and adjust pressure difference between charge and discharge states as a matter of routine optimization to maintain structural integrity and performance of the electrode performance. The claimed difference (≤ 0.9 MPa) represents a result-effective variable, where optimizing the pressure differential would have been within the ordinary skill in the art.
Regarding claim 3, Kudo and Ueki teach the limitations of claim 1, as stated above. Claim 3 recites the strain A. As discussed above, Kudo teaches the same polyethylene-based separator material ([0040]). Ueki teaches applying pressure to the electrode assembly ([0010]). The strain A represents a response of the separator material to applied pressure and temperature conditions, and thus constitutes a result-effective variable. Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art to adjust and optimize such a variable through routine experimentation to achieve desired mechanical and electrochemical performance. Accordingly, the recited strain does no further distinguish the claimed invention.
Regarding claim 4, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo teaches the separator is made of polyethylene-based resin ([0040]). Kudo further teaches separator has air permeability resistance of 250 sec/100 mL or less (Table 1).
Regarding claim 5, Kudo and Ueki teach the limitations of claim 1, as stated above. Claim 5 states pressure P0 is 0.40 MPa or more and 1.40 MPa or less. Kudo teaches applying compressive stress to an electrode assembly, including values of 0.9 MPa and 1.1 MPa, which falls within the claimed range ([0010]). Ueki further teaches applying pressure to an electrode assembly ([0010]). The claimed pressure range therefore encompasses values expressly taught by the prior art. Additionally, the selection of a pressure within the claimed range constitutes a result-effective variable, as pressure directly impact separator deformation and overall battery performance. Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art to select and optimize the applied pressure within the claimed range to achieve desired operational characteristics.
Regarding claim 6, Kudo and Ueki teach the limitations of claim 2, as stated above. Kudo fails to teach pressure P1 is 1.30 MPa or more and 2.00 MPa or less. Ueki teaches applying pressure greater than 0.1 MPa to an electrode assembly ([0010]). The claimed range overlaps and with and falls within a range that would have been obtained through routine adjustment of operating conditions. The selection of a pressure within the claimed range represents a result-effective variable, as pressure directly affects mechanical stability and battery performance. It would have been obvious to one of ordinary skill in the art to optimize the applied pressure within such a range to achieve desired results.
Regarding claim 7, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo teaches the separator is made of polyethylene-based resin ([0040]). Kudo further teaches the average thickness of the separator is 3 μm or more and 100 μm or less ([0028]). It is well established that where the claimed ranges overlap or lie within the ranges disclosed by the prior art, a prima facie case of obviousness exists. Therefore, it would have been obvious to one of the ordinary skills in the art to select thickness within the claimed ranges as a matter of routine optimization of a result-effective variable.
Regarding claim 8, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo further teaches a separator ([0022], [0040]) that includes a substrate layer ([0022]), a coating layer containing particles ([0031]), and a binder formed on the surface or both surfaces of the substrate layer ([0022]).
Regarding claim 9, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo further teaches an energy storage apparatus comprising the energy storage device according to claim 1 which is bound in a constant size ([0035]).
Regarding claim 10, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo further teaches that secondary batteries are used in automobiles in the background of the invention ([0002], [0036]). Ueki also teaches a battery employed in an automobile ([0113], Fig. 10). Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to incorporate the energy storage device as taught by Kudo into an automobile as taught by Ueki. The combination merely involves the use of a known battery in its intended environment, yielding predictable results.
Regarding claim 11, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo further teaches that a battery functions as a power source ([0002]). Ueki further teaches that such batteries may be used as power sources for devices such as automobiles ([0021], Fig. 10). Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to utilize the battery of Kudo as a power source for an electronic device as suggested by Ueki. The modification amount to applying a known battery to a known use, which would have yielded predictable results.
Regarding claim 12, Kudo teaches an energy storage device ([0016]), comprising:
An electrode assembly with a positive electrode and negative electrode are stacked with separator in between ([0041], negative electrode 20, positive electrode 30, separator 50);
An electrolyte solution ([0033]);
A case which houses ([0034], Fig. 1, battery case 10):
The electrode assembly ([0032]);
The electrolyte solution ([0032-0034]);
The electrode assembly is in a state where a load is applied ([0032-0034]):
Additionally, Kudo teaches the separator is made of polyethylene-based resin ([0040]).
Kudo fails to teach the difference between pressure P0 and pressure applied P1 to the electrode assembly in a charge state of 0.9 MPa or less. However, Kudo ([0042]) and Ueki (0010]) teach controlling applied pressure to electrode assemblies within defined ranges. Kudo and Ueki are considered analogous art to the claimed invention because they are in the same field of endeavor of battery electrode assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to control and adjust pressure difference between charge and discharge states as a matter of routine optimization to maintain structural integrity and performance of the electrode performance. The claimed difference (≤ 0.9 MPa) represents a result-effective variable, where optimizing the pressure differential would have been within the ordinary skill in the art.
Regarding claim 13, Kudo and Ueki teach the limitations of claim 1, as stated above. Kudo further teaches a separator ([0022], [0040]) that includes a substrate layer ([0022]), a coating layer containing particles ([0031]), and a binder formed on the surface or both surfaces of the substrate layer ([0022]). Additionally, Kudo teaches a layer containing inorganic particles ([0031]).
Regarding claim 14, Kudo and Ueki teach the limitations of claim 12, as stated above. Kudo further teaches a separator ([0022], [0040]) that includes a substrate layer ([0022]), a coating layer containing particles ([0031]), and a binder formed on the surface or both surfaces of the substrate layer ([0022]). Additionally, Kudo teaches a layer containing inorganic particles ([0031]).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. 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 Tamara Orduna whose telephone number is (571)431-1457. The examiner can normally be reached Mon-Fri 8:00-5:00 EST.
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/TAMARA ORDUNA/Examiner, Art Unit 1776
/Jennifer Dieterle/Supervisory Patent Examiner, Art Unit 1776
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