Development of an optical temperature sensor based on composite liquid crystals for battery manufacturing
Scientists at the Institute of Transport Systems and Technologies of the National Academy of Sciences of Ukraine have developed and patented an optical temperature sensor based on composite liquid crystals – Ukrainian Patent No. 143003. As composites, they proposed using liquid crystals with magnetic nanoparticles – ferromagnetic nematics, which, depending on the concentration of nanoparticles, change the phase transition temperature to the isotropic state (melting temperature). This change alters their optical properties and is instantly detected by the monitoring system. These temperature sensors can be used to monitor temperature regimes in battery manufacturing to provide accurate information about temperature field changes both inside and near technological equipment and in personnel areas.
The optical temperature sensor based on composite liquid crystals belongs to optical temperature control devices for remote monitoring systems. Optical temperature sensors are already in use in modern manufacturing and can be applied in battery plants.
Modern battery manufacturing, in the face of fluctuating market demands, is required to quickly adjust production loads on technological equipment when production plans change and frequently test new products in laboratories. All of this requires careful monitoring of temperature regimes both inside and near technological equipment and in personnel areas. Optical threshold temperature sensors based on liquid crystals can provide remote temperature monitoring with high accuracy due to the high sensitivity of the optical properties of liquid crystals to changes in phase state, as well as the use of fiber-optic communication. The principle of operation of such sensors is based on the fact that when a threshold temperature is reached, the thermosensitive element of the sensor (crystal or liquid crystal) undergoes significant changes in its optical properties (such as light transmission). These changes are detected by the photodetector of the sensor, which sends a signal to the operator or the automated monitoring system.
In this new technical solution, liquid crystals with magnetic nanoparticles – ferromagnetic nematics – are proposed as composites. Joint research by scientists from the "Department of Electrotechnical Complexes and Chemical Power Sources for Transport Purposes (No. 6)" at the Institute of Transport Systems and Technologies of the National Academy of Sciences of Ukraine and the "Department of Magnetism" at the Institute of Physics of the Slovak Academy of Sciences (Košice) conducted under a scientific cooperation agreement, showed that depending on the concentration of nanoparticles, these composites change the phase transition temperature to the isotropic state (melting temperature). This alters their optical properties, which are instantly detected by the monitoring system. The use of the necessary set of thermosensitive elements in the device allows for precise control of temperature regimes in battery manufacturing within a specified temperature range.
