Abstract: In one aspect, thermal energy storage systems are described herein. In some embodiments, such a system comprises a container, a heat exchanger disposed within the container, and a phase change material (PCM) disposed within the container. The heat exchanger comprises an inlet pipe, an outlet pipe; and a number n of plates in fluid communication with the inlet pipe and the outlet pipe, wherein n is at least 2. The inlet pipe, outlet pipe, and plates are arranged and connected such that a fluid flowing from the inlet pipe and to the outlet pipe flows through the plates in between the inlet pipe and the outlet pipe. The PCM disposed within the container is also in thermal contact with the plates.

Abstract: A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.

Abstract: A thermal battery assembly includes a modules configured to be stacked vertically on top of each other. The modules includes an electronics module; a first tank module; and a second tank module. A base defines a bottom of the stack and is configured to receive thereon the lowermost module of the stack for supporting the stack on a floor. Each tank module includes a phase change material (PCM); a heat exchanger assembly with heat exchangers immersed in the phase change material, a first set thereof defining a PCM charging circuit, and a second set defining a PCM discharging circuit; a first exterior connection port configured for fluid communication with an inflow of the PCM discharging circuit and a second exterior connection port configured for fluid communication with an outflow of the PCM discharging circuit. Heating or cooling capacity can be increased by adding another tank module to the stack.

Abstract: In one aspect, thermal energy storage systems are described herein. In some embodiments, such a system includes at least one active thermal storage battery and at least one passive thermal storage battery. The at least one active thermal storage battery includes a container, a heat exchanger disposed within the container, and a first phase change material disposed within the container and in thermal contact with the heat exchanger. The at least one passive thermal storage battery comprises a plurality of thermal storage cells, individual thermal storage cells comprising a container having an interior volume, and a second phase change material disposed within the interior volume of the container.