A Chinese research institution has revealed that it has made a breakthrough in its quest for more enduring fuel solutions for drones.
Called the High-Specific-Power Cathode-Closed Air-Cooled Stack, the hydrogen-based solution was developed by the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences, and is reported to have passed the sci-tech achievement appraisal.
The technology passed the scientific and technological achievement appraisal organised by the China Petroleum and Chemical Industry Federation.
The appraisal committee approved the technology, stating that the achievement is highly innovative, featuring advanced technical indicators and possessing independent intellectual property rights.
Reports from China claim that the stack's specific power ranks among the highest in the world, and the overall technology has reached an internationally leading level.
Dubbed it the "hydrogen heart" for industrial-grade drones, it combines a lightweight design, high power output and air-cooling technology, and is capable of doubling the flight endurance of industrial-grade drones.
A hydrogen-powered drone equipped with this new stack successfully completed a test flight this past Sunday in Dalian, northeast China's Liaoning Province, demonstrating excellent performance on key indicators.
There was no immediate information on long the drone stayed in the air on one charge. Which is a rea bummer because what is the point of publicising a story on a supposed solution to drone endurance with no specific figures to back the claim?
The air-cooled stack achieved a specific power as high as 1,970 watts per kilogram and an area power density of 1.15 watts per square centimeter.
With the rapid growth of the drone technology as the primary driver of low-altitude economy in China, there has been a growing gap between the advancement drone capabilities in industrial applications and their capacity to stay in the air for a long time.
Traditional lithium batteries have not cut it so far, and the heavy weight of current fuel cell systems are emerging as major constraints hindering the progress of the drone industry.
This "hydrogen heart" has achieved the transition from laboratory development to large-scale application, said Chen Zhongwei, the project's technical lead and director of the State Key Laboratory of Catalysis at the DICP.
"The endurance of industrial drones equipped with this system has more than tripled compared with that of conventional batteries," said Zhongwei.
He added that the technology has already been deployed in scenarios including forestry, agriculture, power grid inspection and emergency response missions.
You have to give props to the Chinese for their serious approach to solving the drone endurance issue: the news of the hydrogen heart landed just as other researchers in the country announced that they had developed a new approach to significantly enhance the performance of lithium-sulfur batteries, a breakthrough that could one day enable drones to fly much farther on a single charge.
A team led by Tsinghua Shenzhen International Graduate School (Tsinghua SIGS) has proposed a new solution by introducing a "premediator" for sulfur electrochemistry into lithium batteries.
"Think of it as a special additive that sleeps inside the battery until it is needed," explained Zhou Guangmin, a researcher at Tsinghua SIGS.
“When the sulfur reaction starts, the additive wakes up right where the action is and begins to work.”
Once active, this molecule grabs onto the soluble intermediates and keeps them from drifting away. It also helps build fast lanes for the electrical reactions, making the whole process much smoother and more efficient, Zhou said.
The study, recently published in the journal Nature, opens a new path toward longer-lasting, more powerful batteries for low-altitude aviation and beyond.
Most conventional drones currently rely on lithium-ion batteries, which are approaching their energy density limits. Their energy density – the amount of power stored per unit of weight – typically falls below 300 watt-hours per kilogram, leading to the "range anxiety" that restricts flight duration.
Lithium-sulfur batteries are considered a promising alternative due to their high theoretical energy density, as well as the abundance and low cost of sulfur. However, in practice, these batteries have faced a major hurdle, as during charging and discharging, sulfur undergoes a complex chemical process that generates lots of soluble intermediates.
These intermediates tend to drift away, slow down the reactions, and waste energy.
The team also redesigned the reaction network at the molecular level. The newly developed molecule reduces the battery's internal resistance by 75 percent compared to conventional designs. In tests, the new battery ran stably for 800 charge-discharge cycles, retaining nearly 82 percent of its capacity.
More impressively, the team constructed a practical prototype pouch cell with an energy density of 549 watt-hours per kilogram, nearly double that of many standard drone batteries currently in use.
"For drones, this matters a lot. Higher energy density means longer flight times, bigger payloads, and more working range. A delivery drone could fly farther to drop off packages,” Zhou said.
“A power line inspection drone could cover more towers in one go. A search-and-rescue drone could stay in the air longer when every minute counts."
The team believes their molecular design strategy can also be extended to other fields, including flow batteries, lithium-metal batteries, and even direct battery recycling processes.