# US 12,000,659 B2 · Heat exchange system for freezing a phase change material and methods thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,659 B2 - Document ID: US12000659B2 - Status: Granted - Kind: B2 - Application number: 17/045,445 - Filed: 2019-04-04 - Published: 2021-02-11 - Granted: 2024-06-04 - Earliest claimed: 2018-04-04 - Assignees: Active Energy Systems - Applicants: Active Energy Systems - Inventors: Mitchell Ishmael; Levon Atoyan; Grady J. Iliff - Web page: https://patentgrep.com/patent/US12000659B2 ## CPC - C09D 5/00: Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced {(electrically insulating plastics, resins or waxes H01B3/30)}; Filling pastes - F28D 20/021: {the latent heat storage material and the heat-exchanging means being enclosed in one container (F28D20/023 - F28D20/028 take precedence)} - C09K 5/063: {Materials absorbing or liberating heat during crystallisation; Heat storage materials} - F28F 19/00: Preventing the formation of deposits or corrosion, e.g. by using filters {or scrapers} - F28F 21/067: {Details} - F28F 2245/00: Coatings; Surface treatments - Y02E 60/14: Thermal energy storage - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A heat exchange system including a tank, a phase change material (PCM) held in the tank, an immiscible liquid layer held in the tank, a heat exchanger located within the immiscible liquid layer, and a distributor located above the heat exchanger. The immiscible liquid layer has a density lower than a density of the PCM and is located above the PCM. The distributor is configured to introduce a plurality of PCM droplets into the immiscible liquid layer and above the heat exchanger. ## Claims ### Claim 1 A heat exchange system comprising: a tank; a phase change material (PCM) held in the tank; an immiscible liquid layer held in the tank, wherein the immiscible liquid layer has a density lower than a density of the PCM and is located above the PCM; a heat exchanger coated with an icephobic polymer coating, the heat exchanger located within the immiscible liquid layer and in contact with the PCM configured to freeze at least a portion of the PCM; a distributor located above the heat exchanger configured to introduce a plurality of PCM droplets into the immiscible liquid layer and above the heat exchanger; and one or more secondary storage vessels containing liquid PCM and located externally to the tank, the one or more secondary storage vessels configured to add the liquid PCM to the tank, thereby bringing frozen PCM into contact with the heat exchanger, and wherein the heat exchanger is further configured to receive a warm heat transfer fluid pumped through the heat exchanger to melt the frozen PCM, thereby lowering a temperature of the warm heat transfer fluid. ### Claim 2 (depends on 1) The system of claim 1, wherein the icephobic polymer coating is selected from the group consisting of poly(hexafluoropropylene), polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), perfluoroalkoxy alkane (PFA), polychlorotrifluoroethylene (PCTFE), polytrifluoroethylene, or combinations thereof. ### Claim 3 (depends on 1) The system of claim 1, wherein the PCM is water and optionally includes one or more of an ice nucleating agent or a salt. ### Claim 4 (depends on 3) The system of claim 3, wherein the PCM has a freezing point between −10° C. and 10° C. ### Claim 5 (depends on 1) The system of claim 1, wherein the distributor is a spray nozzle. ### Claim 6 (depends on 1) The system of claim 1, wherein the heat exchanger is a plate-based heat exchanger. ### Claim 7 (depends on 6) The system of claim 6, wherein the heat exchanger further comprises: a plurality of tube passes; and one or more plates comprising: a plate angle of 45° to 90° from horizontal. ### Claim 8 (depends on 1) An energy storage system comprising the heat exchange system of claim 1, the energy storage system further comprising: a heat exchanger inlet and a heat exchanger outlet, wherein the heat exchanger inlet and heat exchanger outlet provide thermal communication between the energy storage system and one or more process units during charging and discharging. ### Claim 9 (depends on 8) The energy storage system of claim 8, further comprising one or more pumps for transferring PCM, immiscible fluid, or both, between the tank and the one or more secondary storage vessels, or an external device. ### Claim 10 (depends on 1) An energy storage method using the system of claim 1, the method comprising: charging the system by freezing the liquid PCM; and discharging the system by melting the frozen PCM, wherein the energy storage method prohibits an accumulation of the frozen PCM on the heat exchanger during charging. ### Claim 11 (depends on 10) The method of claim 10, wherein charging comprising: pumping liquid phase PCM from a bottom of the tank to a top of the tank; contacting the liquid phase PCM with the heat exchanger; freezing the liquid phase PCM in contact with the heat changer using a cold heat transfer fluid, producing the frozen PCM; accumulating the frozen PCM below the heat exchanger at an interface between the liquid phase PCM and the immiscible liquid layer. ### Claim 12 (depends on 10) The method of claim 10, further comprising removing at least a portion of the immiscible fluid layer from the tank to the secondary storage vessel. ### Claim 13 (depends on 1) The system of claim 1, wherein the distributor is configured to introduce the plurality of PCM droplets and let the plurality of liquid PCM droplets thermally contact the heat exchanger. ### Claim 14 (depends on 13) The system of claim 13, wherein the heat exchanger is configured to at least partially freeze the plurality of PCM droplets before losing contact with the heat exchanger surface, and the icephobic polymer coating with the immiscible liquid layer prevents accumulation of at least partially frozen PCM on the heat exchanger surface. ### Claim 15 (depends on 13) The system of claim 13, wherein upon thermally contacting the heat exchanger, the plurality of PCM droplets are at least partially frozen, forming at least partially frozen droplets which fall from the heat exchanger toward an interface between the liquid PCM and the immiscible fluid. ### Claim 16 A heat exchange method for exchanging heat between a heat transfer fluid and a phase change material (PCM), the method comprising: holding an immiscible fluid layer in a tank; feeding a plurality of liquid PCM droplets into the tank proximate a top of the tank; contacting the plurality of liquid PCM droplets on a heat exchanger and freezing the liquid PCM, producing a solid PCM; prohibiting accumulation of the solid PCM on a surface of the heat exchanger via an icephobic polymer coating on the surface of the heat exchanger and the immiscible fluid layer; accumulating the solid PCM in the tank; adding liquid PCM from a secondary storage vessel to the tank, thereby bringing the frozen PCM into contact with the heat exchanger; pumping a warm heat transfer fluid through the heat exchanger; melting the frozen PCM; and lowering a temperature of the warm heat transfer fluid. ### Claim 17 (depends on 16) The method of claim 16, further comprising pumping liquid PCM from the tank and using said pumped liquid PCM as the plurality of liquid PCM droplets in the feeding step.