Wireless charging has already become part of everyday life. Smartphones, smartwatches, earbuds and other devices can now receive power without being physically connected to a cable. But researchers are taking the idea much further: wirelessly powering drones while they are still in the air.
A research team has developed a lightweight device that can capture energy from a laser beam and convert it into electricity. The receiver is designed using ideas from solar-cell technology and can be mounted beneath a drone's wing. If the technology can eventually be made practical for real-world flight, drones could potentially remain airborne for much longer without landing to recharge or replace their batteries.
The findings were published on July 29 in the journal Matter & Light.
A New Way to Power Drones
Drones are increasingly being used for forest inspections, disaster monitoring, surveillance, deliveries and other tasks that require them to stay in the air for long periods. However, battery capacity remains one of their biggest limitations.
A drone can only fly for as long as its battery provides enough energy. Once the battery becomes low, the drone has to return to the ground for charging or replacement.
Researchers at the Civil Aviation University of China are exploring a different approach: sending energy to the drone instead of storing all of it inside the drone.
"Imagine a future where drones inspecting forests, monitoring disasters, or delivering packages no longer need to land frequently to replace batteries," says senior author Jianhua Han.
The basic idea is similar to wireless charging, but instead of using a charging pad, the energy would travel through the air in the form of a focused laser beam.
Turning Laser Light Into Electricity
The heart of the system is a special device called a perovskite laser cell-thermoelectric (PLC-TE) tandem device.
Unlike conventional solar cells, which are designed mainly to work with sunlight, this device is optimized to receive energy from a laser.
The perovskite layer absorbs the laser's energy and converts it into electricity. However, not all of the laser energy can be converted directly into useful power. Some of it becomes heat.
This is where the thermoelectric part of the device becomes important.
The thermoelectric layer can use a temperature difference between its two sides to generate additional electricity. In simple terms, the hotter one side is compared with the other, the more useful energy the thermoelectric system can potentially produce.
But this creates another problem.
Heat Became a Major Challenge
Powerful lasers can generate a significant amount of heat when they strike the receiver. Too much heat can reduce the efficiency of the system and potentially damage the device.
During testing, the researchers discovered just how serious the problem could become.
"When we tested the device under a high-power laser, the thermal camera showed temperatures of 80 to 90°C (176 to 194°F)," Han explains.
That was considerably hotter than expected.
The researchers therefore needed to find a way to prevent the receiver from overheating while it continued to absorb energy from the laser.
Nanocrystals Help Keep the System Cool
To control the heat, the researchers added specialized nanocrystals to the PLC-TE device.
These nanocrystals do not conduct heat easily. They essentially act as a thermal barrier, slowing down the movement of heat through the device.
This helps the receiver maintain a useful temperature difference between its hot and cold sides. As a result, the thermoelectric layer can continue generating electricity more effectively during extended laser exposure.
The approach produced promising results.
When tested using a green laser, the system converted 38.49% of the incoming laser energy into electricity. According to the researchers, this is among the highest efficiencies reported for this type of technology under similar conditions.
That efficiency is important because a wireless power system needs to make good use of the energy delivered to it. If too much energy is lost as heat, the system becomes less practical.
The Drone's Wing Becomes Part of the Cooling System
The researchers did not stop at testing the device in the laboratory.
They also wanted to see how the technology could work when integrated into an aircraft.
For their proof of concept, they installed the receiver beneath the wing of a stationary drone model. They also created air channels through the wing.
When a green laser was directed at the receiver, the system generated enough electricity to power the model's propeller.
Interestingly, the wing design provided another benefit: airflow helped cool the device.
As air moved through the channels, it cooled the colder side of the thermoelectric layer. This improved the temperature difference across the device and helped increase its overall performance.
This is an important step because it shows that the researchers are thinking beyond simply creating an efficient material.
"Previous studies largely focused on the materials or the device itself," Han says. "We wanted to think beyond the laboratory, to how the system could actually be integrated into an aircraft, cooled during operation, and made compatible with flight."
In other words, the challenge is not just about developing a better solar cell. It is also about designing an entire system that can work safely on a moving aircraft.
The Technology Is Not Ready for Flying Drones Yet
Despite the promising demonstration, the system is still at an early stage.
The device has not yet been tested on a flying drone. The next step will be to install it on a lightweight drone and test whether it can reliably receive laser power outdoors.
Several major challenges remain.
One of the biggest is tracking. A laser beam must remain accurately aimed at a moving drone. Even a small change in the drone's position could cause the beam to miss the receiver.
Researchers will also have to address safety concerns. A powerful laser aimed into the sky could pose risks to people, aircraft and other objects if it is not carefully controlled.
Outdoor conditions could create additional difficulties. Wind, clouds, sunlight, distance and the drone's movement could all affect how efficiently the system works.
Could Lasers Eventually Replace Drone Batteries?
The researchers are not suggesting that batteries will disappear anytime soon.
Instead, laser power could potentially supplement a drone's onboard battery, allowing it to fly for much longer before needing to land.
For example, a drone could use its battery during takeoff and when operating outside the range of the laser. Once it enters a designated area, a ground-based laser could continuously send energy to its receiver.
Such a system could be particularly useful for long-duration missions where returning to a charging station is inconvenient.
Forest monitoring is one possible application. Disaster-response drones could also benefit by staying airborne for longer periods while surveying affected areas. Delivery and inspection drones are other potential uses.
However, turning the current laboratory demonstration into a reliable commercial system will require considerable engineering work.
"Our work demonstrates the possibility of 'refueling aircraft with light,'" says Han. "Going from 1 to 100 will require solving many engineering challenges, but we hope this provides a starting point for future development."
A Glimpse of Wireless Power in the Sky
The concept of charging a drone with a laser may sound futuristic, but the underlying principle is straightforward: send light to the aircraft and convert that light into electricity.
The researchers' work addresses one of the biggest obstacles—heat—and demonstrates that the receiver can be integrated into a drone's wing while benefiting from airflow for cooling.
The technology still needs to prove that it can work reliably on a moving drone in real outdoor conditions. If those challenges can eventually be solved, however, laser-powered wireless charging could open a new path toward longer-lasting drones that spend less time on the ground and more time in the sky.
Reference: Sb2Se3 nanocrystals enable efficient perovskite-thermoelectric tandem devices for laser-powered unmanned aerial vehicles, Matter & Light (2026). DOI: 10.1016/j.matlit.2026.100066
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