The present disclosure is directed to nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy from captured high energy photons. Huge numbers of electrons in the intra-band of atom can be liberated through bound-to-free transition when coupled with high energy photons. If a power conversion process effectively utilizes these liberated electrons in an avalanche form through a power conversion circuit, the power output will be drastically increased. The power density of a system can be multiplied by the rate of high energy photon absorption. The present disclosure describes a system and methods built with multilayers of nuclear thermionic avalanche cells for the generation of energy. The multilayer structure of NTAC devices offers effective recoverable means to capture and harness the energy of gamma photons for useful purposes such as power systems for deep space exploration.

A chargeable atomic battery (CAB), such as a fully ceramic encapsulated radioactive heat source, includes a plurality of CAB units and a CAB housing to hold the plurality of CAB units. Each of the CAB units are formed of a precursor compact including precursor material particles embedded inside an encapsulation material. The precursor material particles include a precursor kernel formed of a precursor material that is initially manufactured in a stable state or an unstable state and convertible into an activated material that is an activated state via irradiation by a particle radiation source. The precursor material particles can include one or more encapsulation coatings surrounding the precursor kernel. The precursor material can include Neptunium-237 and the activated material can include Plutonium-238. A radioisotope thermoelectric generator can include thermoelectrics coupled to the CAB units to convert radioactive emissions of the activated material into electrical power.

A system and method are disclosed for internally heated concentrated solar power (CSP) thermal absorbers. The system and method involve an energy-generating device having at least one heating unit. At least one heating unit preheats the energy-generating device in order to expedite the startup time of the energy-generating device, thereby allowing for an increase in efficiency for the production of energy. In some embodiments, the energy-generating device is a CSP thermal absorber. The CSP thermal absorber comprises a housing, a thermal barrier, a light-transparent reservoir containing a liquid alkali metal, at least one alkali metal thermal-to-electric converter (AMTEC) cell, an artery return channel, and at least one heating unit. Each heating unit comprises a heating device and a metal fin. The metal fin is submerged into the liquid alkali metal, thereby allowing the heating device to heat the liquid alkali metal via the fin.

Provided is a fuel design configured to have a thickness that is equal to or less than a mean-free path of electrons emitted by a radioactive energy source to prevent electrons produced thereby from being stopped within the fuel design and thus decreasing the intensity of bremsstrahlung radiation generated within the fuel design. Additionally provided is a two-phase shielding system including a first shield formed of a first material having a thickness exceeding a mean-free path of an electron emitted from a radioactive source material so as to prevent the electron from passing through the first shield, and a second shield formed of a second material configured to prevent bremsstrahlung radiation generated by the electron from passing through the second shield.

A nuclear microbattery is disclosed comprising: a radioactive material that emits photons or particles; and at least one diode comprising a semiconductor material arranged to receive and absorb photons or particles and generate electrical charge-carriers in response thereto, wherein said semiconductor material is a crystalline lattice structure comprising Aluminium, Indium and Phosphorus.

Provided herein is a method for fabricating a heat source for a radioisotope thermoelectric generator (RTG). The method may include reducing a particle size in a strontium compound by powdering and sieving the strontium compound and/or dissolving the strontium compound into an aqueous solution; mixing the strontium compound with graphite to obtain a strontium-graphite mixture; performing a press to the strontium-graphite mixture; and encapsulating the pressed strontium-graphite mixture into an x-ray shielding to obtain the heat source.

A cooling system and method for Nuclear Thermionic Avalanche Cells (NT A Cs) Through cooling channels disposed within layers of the NTAC. The NTAC uses gamma ray radiations and/or energetic electrons which are emanated from the decay processes of radioactive materials 5 and operates continuously. The cooling system and method maximizes energy output of current NTAC devices, alleviates thermal loading issues inside a NTAC. The cooling system and method may also include radiative means for dissipating thermal energy, or in other embodiments capture thermal energy from a NTAC in addition to electrical energy generated by NTACs. Cooling channels are disposed within the layers of a NTAC and joined to a fluid and/or gas flow control system through top and bottom structures which incorporate cooling channels and allow fluid and/or gas to flow through the layers of a NT AC. Flow control systems may operate the cooling system and method through one or more isolated cooling system loops, and may include sensors, valves, and other flow control means to optimize operation and utilization of the cooling system and method, as well as capture of thermal energy from a NTAC.

A chargeable atomic battery (CAB), such as a fully ceramic encapsulated radioactive heat source, includes a plurality of CAB units and a CAB housing to hold the plurality of CAB units. Each of the CAB units are formed of a precursor compact including precursor material particles embedded inside an encapsulation material. The precursor material particles include a precursor kernel formed of a precursor material that is initially manufactured in a stable state or an unstable state and convertible into an activated material via irradiation by a particle radiation source. The precursor material particles can include one or more encapsulation coatings surrounding the precursor kernel. The precursor material can include Neptunium-237 and the activated material can include Plutonium-238. A radioisotope thermoelectric generator can include thermoelectrics coupled to the CAB units to convert radioactive emissions of the activated material into electrical power.

The present disclosure is directed to a nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy comprising a radioisotope core, a plurality of thin-layered radioisotope sources configured to emit high energy beta particles and high energy photons, and a plurality of NTAC layers integrated with the radioisotope core and the radioisotope sources, wherein the plurality of NTAC layers are configured to receive the beta particles and the photons from the radioisotope core and sources, and by the received beta particles and photons, free up electrons in an avalanche process from deep and intra bands of an atom to output a high density avalanche cell thermal energy through a photo-ionic or thermionic process of the freed up electrons.

The present disclosure is directed to a nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy comprising a radioisotope core, a plurality of thin-layered radioisotope sources configured to emit high energy beta particles and high energy photons, and a plurality of NTAC layers integrated with the radioisotope core and the radioisotope sources, wherein the plurality of NTAC layers are configured to receive the beta particles and the photons from the radioisotope core and sources, and by the received beta particles and photons, free up electrons in an avalanche process from deep and intra bands of an atom to output a high density avalanche cell thermal energy through a photo-ionic or thermionic process of the freed up electrons.