What is the progress of global nuclear battery technology? -Lithium - Ion Battery Equipment
Nuclear batteries have attracted the interest of researchers since 1913. At present, potential nuclear cells are thermionic, thermo optoelectric, direct charge collection, thermionic, scintillation intermediate, alpha voltaics and beta voltaics direct energy conversion. In the last 40 years, the mainstream nuclear battery technology is the radioisotope thermoelectric generator (RTG), which converts the heat generated by the decay of radioactive elements into electrical energy through the Seebeck effect. At present, RTG has been widely used in deep space exploration scenarios, and has become a benchmark for evaluating the efficiency of other nuclear batteries.
At present, the two main factors that restrict the application of RTG are low conversion efficiency and large volume. The conversion efficiency of RTG is only about 6%, which determines that its finished products have high quality and low energy density. In order to make nuclear battery play an advantage in small devices, researchers are working towards the direction of miniaturization of nuclear battery and improvement of battery conversion efficiency.(Lithium - Ion Battery Equipment)
1、 Research progress of nuclear battery technology
According to the energy conversion efficiency and output power of radioisotope batteries, radioisotope batteries can be classified into thermoelectric type, radiation Ford effect type, etc.
1. Thermoelectric isotope battery
Thermoelectric isotope battery can directly collect radiation generated by radioactive isotope decay, or convert it into electrical energy based on Seebeck effect, thermionic/photon emission effect, etc. through energy exchange devices. At present, thermoelectric isotope battery has low conversion efficiency due to low thermoelectric merit of traditional materials and high battery heat leakage. With the development of new thermoelectric materials and the improvement of battery structure, it is expected to improve the performance of thermoelectric batteries.
BihongLin et al. of Huaqiao University conducted optimization research on the thermal ion temperature difference hybrid power generation module. First, they prepared a thermionic semiconductor thermoelectric emission battery module based on the non-equilibrium thermodynamic theory. Using the model, they calculated the optimization range of its output power, conversion efficiency, module work function, current density, current and load, and realized the ladder utilization of energy sources.
2. Radiant volt effect battery
The working principle of the radioactive volt effect isotope battery is to irradiate the semiconductor material with the radiation emitted by the radioactive isotope decay. The semiconductor generates a large number of electron hole pairs. The electron hole pairs are separated under the effect of an electric field, and are connected to an external circuit to realize the power output. Therefore, the isotope battery with the radiation volt effect is more hopeful to realize miniaturization, and has potential applications in the fields of integrated circuits and micro electro mechanics.
Zhang Jin et al. of Nanjing University prepared two kinds of γ X-ray, PN type aluminum gallium indium phosphorus (AlGaInP) semiconductor and zinc sulfide: copper (ZnS: Cu) fluorescent material, 4-layer nuclear cell. One is a 4-layer radio wave battery (FRVB) with a volume of 1.00cm3, and the other is a 4-layer double effect nuclear battery (FDEB) with a volume of 1.03cm3. The output performance of the two batteries was measured by X-ray tube irradiation. The results show that the output power of nuclear cells in parallel is significantly higher than that in series. However, the output power and power density of FDEB are 57.26nW and 55.59nW/cm3 respectively, which are 5 times higher than those of parallel FRVB. Each sub battery unit of FDEB is connected in different ways according to actual needs. Different output current and voltage are obtained, but the output power is not different. They also used MCNP5 to simulate the X-ray energy deposition of AlGaInP or ZnS: Cu layers in FDEB. The results show that a small amount of energy deposition in the fluorescent layer can significantly improve the electrical output performance of the nuclear battery. Multilayer double effect energy conversion mechanism can improve the electrical output performance of nuclear battery.
At present, the two main factors that restrict the application of RTG are low conversion efficiency and large volume. The conversion efficiency of RTG is only about 6%, which determines that its finished products have high quality and low energy density. In order to make nuclear battery play an advantage in small devices, researchers are working towards the direction of miniaturization of nuclear battery and improvement of battery conversion efficiency.(Lithium - Ion Battery Equipment)
1、 Research progress of nuclear battery technology
According to the energy conversion efficiency and output power of radioisotope batteries, radioisotope batteries can be classified into thermoelectric type, radiation Ford effect type, etc.
1. Thermoelectric isotope battery
Thermoelectric isotope battery can directly collect radiation generated by radioactive isotope decay, or convert it into electrical energy based on Seebeck effect, thermionic/photon emission effect, etc. through energy exchange devices. At present, thermoelectric isotope battery has low conversion efficiency due to low thermoelectric merit of traditional materials and high battery heat leakage. With the development of new thermoelectric materials and the improvement of battery structure, it is expected to improve the performance of thermoelectric batteries.
BihongLin et al. of Huaqiao University conducted optimization research on the thermal ion temperature difference hybrid power generation module. First, they prepared a thermionic semiconductor thermoelectric emission battery module based on the non-equilibrium thermodynamic theory. Using the model, they calculated the optimization range of its output power, conversion efficiency, module work function, current density, current and load, and realized the ladder utilization of energy sources.
2. Radiant volt effect battery
The working principle of the radioactive volt effect isotope battery is to irradiate the semiconductor material with the radiation emitted by the radioactive isotope decay. The semiconductor generates a large number of electron hole pairs. The electron hole pairs are separated under the effect of an electric field, and are connected to an external circuit to realize the power output. Therefore, the isotope battery with the radiation volt effect is more hopeful to realize miniaturization, and has potential applications in the fields of integrated circuits and micro electro mechanics.
Zhang Jin et al. of Nanjing University prepared two kinds of γ X-ray, PN type aluminum gallium indium phosphorus (AlGaInP) semiconductor and zinc sulfide: copper (ZnS: Cu) fluorescent material, 4-layer nuclear cell. One is a 4-layer radio wave battery (FRVB) with a volume of 1.00cm3, and the other is a 4-layer double effect nuclear battery (FDEB) with a volume of 1.03cm3. The output performance of the two batteries was measured by X-ray tube irradiation. The results show that the output power of nuclear cells in parallel is significantly higher than that in series. However, the output power and power density of FDEB are 57.26nW and 55.59nW/cm3 respectively, which are 5 times higher than those of parallel FRVB. Each sub battery unit of FDEB is connected in different ways according to actual needs. Different output current and voltage are obtained, but the output power is not different. They also used MCNP5 to simulate the X-ray energy deposition of AlGaInP or ZnS: Cu layers in FDEB. The results show that a small amount of energy deposition in the fluorescent layer can significantly improve the electrical output performance of the nuclear battery. Multilayer double effect energy conversion mechanism can improve the electrical output performance of nuclear battery.
