Systems, methods, and devices for energy storage are provided. A system for energy storage includes a thermomechanical-electrical conversion subsystem for converting energy formats and a mechanical and thermal storage unit for storing energy formats. The thermomechanical-electrical conversion subsystem includes a storage subsystem including a compressor and a first thermal energy exchanger and a generation subsystem including a power generator and a second thermal energy exchanger. The storage subsystem compresses a fluid to generate compressed fluid and thermal energy. The generation subsystem generates power from the compressed fluid and the thermal energy. The mechanical and thermal storage unit includes a pressure vessel for storing the compressed fluid and a thermal energy storage for storing the thermal energy generated by the fluid compression and for providing the thermal energy to the generation subsystem for generating power.

Electrochemical actuators including a sealed electrolytic chamber with two or more electrodes disposed therein and associated reservoirs are described. In some embodiments, the electrochemical actuators include one or more rigid structures that are overmolded onto one or more electrodes to form the electrolytic chambers. In some embodiments, multiple rigid structures that are overmolded onto two or separate electrodes may be connected to form one or more electrolytic chambers with a desired configuration of electrodes contained therein. Manufacturing methods and structures related to the formation of an array of electrochemical actuators are also described.

An economical compressed air energy storage (CAES) method effectively utilizing the capacity of space in the air storage portion in CAES plants to reduce the plant costs thereof is provided. An air storage portion is configured from a plurality of vessels, and a film to provide spaces with freely deformable shapes is disposed within each vessel. In the air compression step, the space on one side of the film within each vessel is filled in advance with a cushion gas, air is stored in the space on the other side of the film, and the cushion gas is changed into a fluid with a reduced volume to increase the amount of the air stored in the space on the other side of the film. In the air expansion step, fluid is heated and vaporized to decrease the amount of the air remaining on the other side of the film.

A pumping device, comprising an actuator and a closure, the actuator being connected to the actuator. The pumping device further comprises a collapsible bladder, the collapsible bladder being formed by connecting a plurality of segments, and an included angle being formed between two adjacent segments, wherein at least two adjacent segments are connected to each other by means of a weakened portion.

An economical compressed air energy storage (CAES) method effectively utilizing the capacity of space in the air storage portion in CAES plants to reduce the plant costs thereof is provided. An air storage portion is configured from a plurality of vessels, and a film to provide spaces with freely deformable shapes is disposed within each vessel. In the air compression step, the space on one side of the film within each vessel is filled in advance with a cushion gas, air is stored in the space on the other side of the film, and the cushion gas is changed into a fluid with a reduced volume to increase the amount of the air stored in the space on the other side of the film. In the air expansion step, fluid is heated and vaporized to decrease the amount of the air remaining on the other side of the film.

A system includes a turbine; a first fluid; and a second fluid, wherein the turbine is composed of a rotor assembly having at least one first rotor and at least one second rotor affixed to a shaft and within an enclosure configured to contain the first and second fluids, wherein the energy in a mixture of first and second fluids provided to the at least one second rotor results from vaporization and expansion of the second fluid. A continuous process for converting heat to kinetic energy utilizes the system and includes: mixing the second fluid with the first fluid; vaporization of the second fluid by heat transfer from the first fluid to form a pressurized mixture; and contacting the at least one second rotor with the pressurized mixture to impart rotational motion to the rotor assembly.

A thermo-electrochemical converter includes a working fluid, and first and second membrane electrode assemblies (MEAs). A first chamber is in fluid communication with the first electrode of the first MEA. A second chamber is in fluid communication with the second electrode of the first MEA. A third chamber is in fluid communication with the first electrode of the second MEA. A fourth chamber is in fluid communication with the second electrode of the second MEA. First and second conduits are in fluid communication with the first and third chambers. A fluid handler moves the working fluid from the third chamber to the first chamber through the first conduit. A heat exchanger is in thermal communication with the first and second conduits and is configured to transfer heat from the working fluid in the first conduit to the working fluid in the second conduit.