A heat transfer system is disclosed in which, an electrocaloric material includes a copolymer of a monomer mixture including (i) vinylidene fluoride, (ii) an addition polymerization monomer selected from tetrafluoroethylene, trifluoroethylene, or a monomer smaller than trifluoroethylene, and (iii) a halogenated addition polymerization monomer different than (ii) that is larger than vinylidene fluoride. The electrocaloric material also includes an additive selected from a nucleating agent having a polar surface charge, electrocalorically active solid particles, or a combination thereof. Electrodes are disposed on opposite surfaces of the electrocaloric material, and an electric power source is configured to provide voltage to the electrodes. The system also includes a first thermal flow path between the electrocaloric material and a heat sink, and a second thermal flow path between the electrocaloric material and a heat source.

Heat regenerators and related methods enable heat transfer in an embedded structure of a heat regenerator. The heat regenerators enable a reduction of the pressure drop due to fluid flow through the heat regenerator and consequently an increase of power density. A heat regenerator includes a housing having a primary hot heat exchanger and a primary cold heat exchanger between elements for the oscillation of a primary fluid. The secondary fluid unidirectionally flows from the heat sink into the primary cold heat exchanger. The secondary fluid exits from the primary cold heat exchanger and unidirectionally flows towards the heat source. The secondary fluid S enters the primary hot heat exchanger and exits as the unidirectional flow of the secondary fluid S of the primary hot heat exchanger towards the heat sink. Between both primary heat exchangers, the porous regenerative material is positioned as part of the regenerator.

A heat transfer system cycles between a first mode where a heat transfer fluid is directed to a first electrocaloric module and from the first electrocaloric module to a heat exchanger to a second electrocaloric module while one of the first and second electrocaloric modules is energized, and a second mode where the heat transfer fluid is directed to the second electrocaloric module and from the second electrocaloric module to the heat exchanger to the first electrocaloric module, while the other of the first and second electrocaloric modules is energized. The modes are repeatedly cycled in alternating order directing the heat transfer fluid to cause a temperature gradient in each of the first and second electrocaloric modules, and heat is rejected to the fluid from the heat exchanger or is absorbed by the heat exchanger from the fluid.

An apparatus can comprise a DC power supply to generate a DC electrical signal, a pulse generator to generate an electrical pulse, and an electrical element. The pulse generator and the DC power supply can be electrically coupled together. The electrical element can receive the DC electrical signal and the electrical pulse. The electrical element can generate a magnetic field in response to receiving the DC electrical signal and cool in response to receiving the electrical pulse.

A heat transfer system (310) is disclosed that includes a first electrocaloric module (62) comprising a first electrocaloric material, a first high-side voltage electrode, and a first low-side voltage electrode, arranged to impart an electric field to the electrocaloric material. The system also includes a second electrocaloric module (64) comprising a second electrocaloric material, a second high-side voltage electrode, and a second low-side voltage electrode, arranged to impart an electric field to the electrocaloric material. A bi-directional power transfer circuit (60) is also included arranged to alternately transfer power from the electrodes of the first electrocaloric module (62) to the second electrocaloric module (64), and from the electrodes of the second electrocaloric module (64) to the first electrocaloric module (62).

The invention provides a method for cooling fluid having the steps of supplying a fluid at a first temperature T1, raising the temperature of the fluid to a second temperature T2 through contact with an electric field, contacting the fluid with a heat exchanger to decrease its temperature to a third temperature T3, removing the electric field to decrease the temperature of the fluid to a fourth temperature T4, and applying a heat load to the fluid to increase the temperature of the fluid to T1. Also provided is a system for cooling fluid having a closed loop having a first region subject to an electric field, a second region in contact with a heat exchanger, a third region remote from the electric field, and a fourth region contacting a heat load.

A heat transfer system is disclosed that includes a plurality of electrocaloric elements (12) including an electrocaloric film (14), a first electrode (16) on a first side of the electrocaloric film, and a second electrode (18) on a second side of the electrocaloric film. A fluid flow path (20) is disposed along the plurality of electrocaloric elements, formed by corrugated fluid flow guide elements (19).

A heat transfer system is disclosed including a plurality of modules arranged in a stack. The stack modules include electrocaloric element and electrodes on each side of the film. A fluid flow path is disposed between two or more electrocaloric elements. A first electrical bus element (18) in electrical contact with the first electrode (14), and a second electrical bus element (20) in electrical contact with second electrode (16). The first electrical bus element is electrically connected to at least one other electrical bus of another electrocaloric element in the stack at the same polarity as said first electrical bus, or the second electrical bus element is electrically connected to at least one other electrical bus of another electrocaloric element in the stack at the same polarity as said second electrical bus.

A method of making an electrocaloric element includes dissolving or dispersing an electrocaloric polymer in an organic solvent having a boiling point of less than 100 C. at 1 atmosphere to form a liquid composition comprising the electrocaloric polymer. A film of the liquid composition is cast on a substrate, and the organic solvent is evaporated to form a film of the electrocaloric polymer. The film is removed from the substrate and disposed between electrical conductors to form an electrocaloric element.

A method of making an electrocaloric element includes forming conductive layers on opposing surfaces of a film comprising an electrocaloric material to form an electrocaloric element, wherein the forming of the conductive layers includes one or more of: vapor deposition of the conductive layers under reduced pressure for a duration of time, wherein the duration of time under reduced pressure is less than 240 minutes; vapor deposition of the conductive layers under reduced pressure for a duration of time, wherein the duration of time of exposure to conductive material deposition is less than 240 minutes; vapor deposition of the conductive layers under reduced pressure, wherein the reduced pressure is 10 torr to 500 torr; or maintaining the film at a temperature of less than or equal to 200 C. during forming of the conductive layers.