DETAILED CORRESPONDENCE
1. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Notice of Pre-AIA or AIA Status
2. 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
3. In response to the amendment received on 1/22/2026:
Claims 32-51 are pending in the current application. Claim 40 has been amended, Claims 1-31 are cancelled, and Claim 51 is newly added.
The previous objection to the claims has been overcome in light of the amendment.
The previous rejection under 35 USC 112 is withdrawn in light of arguments.
The previous prior art-based rejections have been overcome in light of the arguments and a new rejection is laid out below.
Claim Interpretation
4. All “wherein” clauses are given patentable weight unless otherwise noted. Please see MPEP 2111.04 regarding optional claim language.
Claim Rejections - 35 USC § 103
5. Claims 32-38 and 41-51 are rejected under 35 U.S.C. 103 as being unpatentable over Xu et al. Chem Comm. 2018, 54, 11626-11629 in view of Maschmeyer US PG Publication 2022/0059846.
Regarding Claims 32-35, 38, 41, 43, 45, 48-50, Xu discloses an energy storage device (Fig 1, including solar panel to collect photons, meeting Claim 41) comprising an electrochemical cell comprising a first region (organic phase) (and a method of charging and discharging said electrochemical cell, meeting Claim 50) comprising a first electrode active material (dissolved Br2), and a second region in electrochemical communication with the first region, the second region comprising a second electrode active material (Zn) (meeting Claim 34), wherein the first region comprises a nonpolar liquid (CCl4) (meeting Claim 35), at least one liquid-liquid phase boundary and NO membrane is present between the first and second regions (meeting Claims 43 and 45), the first electrode active material comprises an electroactive species dissolved within the non-polar liquid during charging/discharging, wherein the second electrode active material (Zn) is precipitated and dissolved during the charge/discharge cycle (3rd box on p. 11627, meeting Claim 48), the liquid within the first and second regions are immiscible (box on p. 11626 and 2nd box on p. 11627, meeting Claim 49), and a temperature of operation of the electrochemical cell is less than or equal to 100 °C since charge/discharge is carried out at room temperature (generally understood by the skilled artisan to be 23 °C) (meeting Claim 38) (see highlighted and boxed portions of the attached reference). Xu discloses wherein the active material is Br2 (a liquid at standard conditions) and therefore fails to specifically disclose wherein the first electrode active material comprises an electroactive species in the form of a dissolved gas within the non-polar liquid. However, in the same field of endeavor of zinc-halogen flow battery design that addresses issues of halogen solubility and the effect of this solubility on cell structure, Maschmeyer discloses wherein both bromine and chlorine are known halogen active materials used in a zinc-halogen flow battery, they share the same solubilities in water, for example, and can both be used with similar effect (they are functionally equivalent) (see at least e.g. paras 0003-0005, 0149-0151). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to use chlorine gas (Cl2) (meeting Claim 33) as the active material in the flow battery of Xu because Maschmeyer teaches that these materials are functionally equivalent to one another, having similar solubilities, and interchangeable in technology that addresses similar issues. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. __,__, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
Regarding Claims 36-37, Xu modified by Maschmeyer fails to specifically recite wherein a volumetric or gravimetric density of the electrochemical cell is between 100 and 700 Wh/L or between 100 and 700 Wh/kg, respectively. However, Xu does recite that Br2 is highly soluble in CCl4 and that the concentration of ZnBr2 is very high to improve the energy density of the battery (see highlighted portion on p. 11628) and recites the ZnBr2 volumetric energy density can be e.g. 495.8 Wh/L, and the skilled artisan would expect that given the similarities in Br2 and Cl2, a similar energy density would be available, and so it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to optimize the conditions of Xu to arrive at the high theoretical volumetric energy density of e.g. 495.8 Wh/L to achieve as well-performing battery as possible. The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).
Regarding Claim 42, the skilled artisan would understand that the electroactive species within the non-polar liquid (i.e. Cl2 gas) is substantially absent from the second region, and further, that chlorine gas is present in the first region as a molecular species (Cl2) and the second region comprises a corresponding metal salt (the salt of the transition metal with bromide ion. See Fig. 1 of Xu and box on p. 11626.
Regarding Claim 44, Fig. 1 of Xu shows a positive current collector and terminal (which is necessarily an electronically conductive material) between the first and second regions, and specifically, the cell diagram of Xu shows carbon felt between the first and second regions (see supplemental info; Fig S3), which is an electrically conductive material.
Regarding Claim 46, the skilled artisan would expect a product of an electrochemical reaction of the electroactive species within the non-polar liquid to have a solubility of less than 1 g/L in the non-polar liquid since the same components are present as in the instant claimed invention and regarding composition claims, if the composition is the same, it must have the same properties (see MPEP § 2112.01, II.).
Regarding Claim 47, Xu fails to specifically disclose wherein the second electrode active material comprises Mg, Al, Ca, Li, Na, K, Rb, Cs, Fr, Bi, Cu, Sn, Pb, Ag, Au, Cr, Pt, Cd, Te, Pd, Co, Ti, Mn, La, Sr, Eu, Ra, Zr, Y, Sc, and/or V. However, Maschmeyer discloses wherein zinc and Mg, Ca, K, Na, Al, Fe, and Ni are functionally equivalent active materials used in a halogen-based flow battery (see at least e.g. paras 0149-0151). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to use Mg, Ca, K, Na, Al, Fe, and Ni as the active material in the flow battery of Xu because Maschmeyer teaches that these materials are functionally equivalent to Zn and are interchangeable in technology that addresses similar issues. The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. __,__, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
Further, the skilled artisan would understand that although Xu modified by Maschmeyer does not specifically discuss gravimetric energy density (and only discusses volumetric energy density), given the density of the two liquids used (CCl4 and H2O, which have a density of 1.59 g/cm3 and 1.0 g/cm3, respectively), the wide range of volumetric energy densities that could be attained by the teaching of Xu (up to 495.8 Wh/L) would be equated to gravimetric energy densities in a substantially similar range (and in the claimed range). “A person of ordinary skill in the art is also a person of ordinary creativity, not an automaton.”KSR, 550 U.S. at ___, 82 USPQ2d at 1397. “[I]n many cases a person of ordinary skill will be able to fit the teachings of multiple patents together like pieces of a puzzle.”Id. Office personnel may also take into account “the inferences and creative steps that a person of ordinary skill in the art would employ.”Id. at ___, 82 USPQ2d at 1396.
Regarding Claim 51, the skilled artisan would understand that the Cl2 gas of Xu modified by Maschmeyer, which is the electroactive species, would be in the form of a material that is a gas at room temperature and a pressure of 1 bar. Regarding product and apparatus claims, when the structure recited in the reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent. The Courts have held that it is well settled that where there is a reason to believe that a functional characteristic would be inherent in the prior art, the burden of proof then shifts to the applicant to provide objective evidence to the contrary. See In re Schreiber, 128 F.3d at 1478, 44 USPQ2d at 1478, 44 USPQ2d at 1432 (Fed. Cir. 1997) (see MPEP § 2112.01, I.).
6. Claim(s) 39-40 are rejected under 35 U.S.C. 103 as being unpatentable over Xu et al. Chem Comm. 2018, 54, 11626-11629 in view of Maschmeyer US PG Publication 2022/0059846, as applied to Claim 32, and further in view of Qiu et al. Nat Commun, 11, 4463 (2020).
Regarding Claims 39-40, Xu modified by Maschmeyer discloses the claimed electrochemical cell as described in the rejection of Claim 1, which is incorporated herein in its entirety. Xu fails to specifically recite wherein a temperature of operation of the electrochemical cell is less than or equal to 20 °C or less than or equal to -30 °C. However, in the same field of endeavor of Zn battery design, Qiu discloses that ultralow temperature operation of rechargeable Zn batteries is an important field of research because these batteries are highly promising for conservation of renewable natural resources, and that by breaking up the hydrogen bonds in aqueous electrolyte of the Zn electrode in ZnCl2 electrolyte, operating temperature can be lowered to temperatures lower than previously seen (e.g. -70 °C) (see entire disclosure and especially all boxed portions on p. 2). Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the instant application to optimize the electrolyte solution design of Xu modified by Maschmeyer such that the electrochemical cell can be operated at ultralow temperatures (including at less than or equal to 20 °C or less than or equal to -20 °C) by following the exploration of Qiu because Qiu teaches that Qiu discloses that ultralow temperature operation of rechargeable aqueous Zn batteries is an important field of research because these batteries are highly promising for conservation of renewable natural resources, and that by breaking up the hydrogen bonds in aqueous electrolyte of the Zn electrode in aqueous ZnCl2 electrolyte, operating temperature can be lowered to temperatures lower than previously seen.
Double Patenting
7. Claims 32-33, 35, and 42-49 are rejected on the ground of nonstatutory obviousness-type double patenting as being unpatentable over claims 1-3, 5, 7, 9-1, 15, 16-20 of conflicting US Patent 11,637,341.
Although the conflicting claims are not identical, they are not patentably distinct from each other because:
The combination of conflicting claims 1-3, 5, 7, 9-10, 15-20 read on currently pending claims 32-33, 35, and 42-49.
Conflicting Claims:
1. An electrochemical cell, comprising: a first region comprising a first electrode active material; and a second region in electrochemical communication with the first region, the second region comprising a second electrode active material; wherein: the first region comprises a non-polar liquid; the first electrode active material comprises an electroactive species within the non-polar liquid, the electroactive species present in the non-polar liquid at a concentration of at least 1 mMol; the second electrode active material comprises iron; and the electrochemical cell is configured such that, during at least one period of time during charging and/or discharging, a metallic iron electrode material is present.
2. An electrochemical cell, comprising: a first region comprising a first electrode active material; and a second region in electrochemical communication with the first region, the second region comprising a second electrode active material; wherein: the first region comprises a non-polar liquid; the first electrode active material comprises an electroactive species comprising a dissolved gas within the non-polar liquid; and the electrochemical cell is configured such that, during at least one period of time during charging and/or discharging, the dissolved gas is present in the non-polar liquid at a concentration of at least 1 mMol.
3. The electrochemical cell of claim 1, wherein the electroactive species within the non-polar liquid is substantially absent from the second region.
4. The electrochemical cell of claim 1, wherein at least one liquid-liquid phase boundary is present between the first region and the second region.
5. The electrochemical cell of claim 1, wherein the electroactive species is dissolved within the liquid in which it is contained.
7. The electrochemical cell of claim 1, wherein the electroactive species comprises a dissolved gas.
9. The electrochemical cell of claim 8, wherein the electroactive species in the first region is Cl.sub.2, and the corresponding solubilized ion in the second region is Cl.sup.−.
10. The electrochemical cell of claim 1, further comprising an electronically conductive material between the first region and the second region.
15. The electrochemical cell of claim 1, wherein there is no membrane between the first region and the second region.
16. The electrochemical cell of claim 1, wherein the electroactive species comprises a diatomic halogen, oxygen gas (O.sub.2), carbon dioxide (CO.sub.2), and/or carbon monoxide (CO).
17. The electrochemical cell of claim 1, wherein the electroactive species comprises F.sub.2, Cl.sub.2, Br.sub.2, and/or I.sub.2.
18. The electrochemical cell of claim 1, wherein the non-polar liquid comprises CCl.sub.4, CS.sub.2, chloroform, dichloromethane, ethylbenzene, chlorotoluene, toluene, trichlorobenzene, dichlorobenzene, titanium tetrachloride, benzene, tetrachloroethylene, heptane, hexachloro-butadiene, and/or chromyl chloride.
19. The electrochemical cell of claim 1, wherein a product of an electrochemical reaction of the electroactive species within the non-polar liquid has a solubility of less than 1 g/L in the non-polar liquid.
20. The electrochemical cell of claim 1, wherein the electroactive species within the non-polar liquid comprises Cl.sub.2, and a product of the electrochemical reaction is Cl.sup.−.
Instant Claims:
32. An electrochemical cell, comprising: a first region comprising a first electrode active material; and a second region in electrochemical communication with the first region, the second region comprising a second electrode active material; wherein: the first region comprises a non-polar liquid; and the first electrode active material comprises an electroactive species in the form of a dissolved gas within the non-polar liquid.
33. The electrochemical cell of claim 32, wherein the dissolved gas comprises Cl.sub.2.
35. The electrochemical cell of claim 32, wherein the non-polar liquid comprises carbon tetrachloride.
41. An energy storage device comprising the electrochemical cell of claim 32.
42. The electrochemical cell of claim 32, wherein the electroactive species within the non-polar liquid is substantially absent from the second region.
43. The electrochemical cell of claim 32, wherein at least one liquid-liquid phase boundary is present between the first region and the second region.
44. The electrochemical cell of claim 32, further comprising an electronically conductive material between the first region and the second region.
45. The electrochemical cell of claim 32, wherein there is no membrane between the first region and the second region.
46. The electrochemical cell of claim 32, wherein a product of an electrochemical reaction of the electroactive species within the non-polar liquid has a solubility of less than 1 g/L in the non-polar liquid.
48. The electrochemical cell of claim 32, wherein, when the electrochemical cell is subjected to a charge/discharge cycle, the second electrode active material is precipitated and dissolved.
49. The electrochemical cell of claim 32, wherein the liquid within the first region and the liquid within the second region are immiscible.
50. A method, comprising: charging and discharging an electrochemical cell comprising: a first region comprising a first electrode active material; and a second region in electrochemical communication with the first region, the second region comprising a second electrode active material; wherein: the first region comprises a non-polar liquid; and the first electrode active material comprises an electroactive species in the form of a dissolved gas within the non-polar liquid during at least a portion of the charging and/or discharging.
51. (New) The electrochemical cell of claim 32, wherein the electroactive species is in the form of a material that is a gas at a temperature of 298 K and a pressure of 1 bar.
Response to Arguments
8. Applicant's arguments filed 1/22/2026 have been fully considered and are persuasive. A new prior art rejection is laid out above. The rejection under 35 USC 112b is withdrawn – its inclusion in the first Office action appears to have been a typographical error. The double patenting rejection stands.
Conclusion
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/LISA S PARK/
Primary Examiner, Art Unit 1729