The main drawback of most agricultural drones today is their short flight time, typically lasting only 30–40 minutes on battery power before they must return to Earth for a replacement or recharge. Scientists at Altai State Agricultural University have proposed a technology that could solve this problem. The core of the innovation is a special battery that converts thermal energy into electrical energy, with a graphite rod serving as the key component. When electromagnetic waves heat this graphite rod, built-in thermocouples transform that heat into an electric current. In laboratory experiments using a Russian-made induction heater, the battery begins charging even faster, demonstrating the viability of the concept.
Researchers emphasize that this technology allows the battery to be recharged without the drone returning to the ground. The energy source does not have to be a dedicated emitter; the battery can draw power from almost any heat source. For instance, a drone could hover near power lines, heating mains, or industrial pipes to replenish its charge. Scientists are also exploring the use of infrared lasers for charging. The new battery can hold a charge for up to three days and, unlike standard lithium batteries, its efficiency does not drop in cold weather—its performance may even be better in winter. A patent has been obtained for the technology, though the scientists note that it is not yet ready for mass production; compact directional emitters and manufacturing processes for the graphite batteries still need to be developed.
