Drone technology is advancing quickly.
Until recently, the vast majority of consumer drones have been powered by traditional lithium batteries, but in the quest for greater range, running time and loadbearing capacity, manufacturers are shifting their focus towards hydrogen fuel cells.
This year alone, several companies have brought hydrogen drones to market – heralding a big step change in capability and flight times, whilst opening up some exciting opportunities and potential real world applications.
At AMS Composite Cylinders, we work closely with pioneering companies across the UK and Europe in the development of hydrogen fuel cell systems for drones and UAVs.
In this post, AMS Director, Steve Langron, explores the benefits hydrogen fuel cells are bringing to the next generation of drones, before examining the importance of choosing the right kind of gas cylinder for these systems.
Hydrogen – powering the next generation of UAVs
A shift from electric batteries to hydrogen fuel cells is seen by the drone industry as the single most important factor in the development of the next generation of UAVs.
The biggest advantage that hydrogen fuel cells deliver is weight reduction. Even the most advanced lithium batteries are heavy – a serious drawback when it comes to powering flight! Hydrogen fuel cell systems offer significantly lower weights for the same power output. In practical terms, this increased power to weight ratio enables drones to fly further, for longer, and to carry heavier payloads.
Another benefit of hydrogen is the quick refuelling. Whilst traditional batteries can take several hours to recharge, hydrogen cylinders can be swapped out and refilled with gas in a matter of minutes.
Real world impact
To put things in perspective, today’s electric battery powered drones have a maximum real world flight time of around 30 minutes. In challenging weather conditions, this can be reduced to 20 minutes or less.
By comparison, the latest hydrogen fuel cell drones offer flight times of up to 3.5 hours – a huge increase that opens up a wide range of opportunities.
Longer flight times don’t just improve the performance and increase the capability of drones in today’s applications, such as aerial photography, media surveillance and search and rescue – they also pave the way for a number of new opportunities.
Perhaps the most obvious of these is cargo delivery. With hydrogen, delivery by drone, such as Amazon’s proposed Amazon Prime Air service, becomes a realistic possibility. Outside of the commercial sector, cargo drones could be used by the emergency services for the responsive delivery of vital medical supplies.
Beyond weight – cylinder technology and hydrogen drones
All hydrogen fuel cell systems need some way of storing the hydrogen on-board. Typically, this means gas cylinders, and choosing the right, lightweight and durable products is essential.
With low weights and high capacity, AMS Type 3 carbon composite cylinders are the natural choice for UAV manufacturers looking to develop larger, longer range drones for a full range of applications.
Although type 4 cylinders (with an interior plastic lining, rather than a metal interior) do offer slightly lower weights than Type 3 – Type 3 fully wrapped cylinders provide the best all-round solution, in terms of:
Type 3 cylinders have a rigid metal liner, which provides significantly better impact tolerance, minimising the chance of breaking in cases of crashes. It takes a lot to damage a carbon composite wrapped cylinder, and should they suffer damage during a crash or collision, they leak. Type 4 cylinders simply aren’t as strong.
Improved filling and capacity
Type 3 cylinders offer faster filling, and unlike type 4 cylinders, this filling isn’t restricted by hot or cold weather. Type 3 cylinders can be filled to a higher pressure than Type 4 cylinders. Hydrogen expands as it heats, and because the aluminium liner conducts heat better than the plastic, it keeps the interior cooler. This results in a better capacity, and as a result, a longer drone range.
Cylinders for hydrogen fuel cells from AMS
AMS Composite Cylinders supplies a full range of advanced, lightweight gas cylinders to aerospace industry customers across the UK and Europe. AMS cylinders are available in a range of capacities, and custom dimensions to suit the requirements of any OEM drone application.
Certified for use worldwide, AMS composite cylinders hold a wide range of quality assurance accreditations including 11119-2, UN-TPED Pi, DOT (USA) and TC (Canada).
Additional information about AMS Composite Cylinders Ltd can be found at www.ams-composites.com.
This blog was written by AMS CC Director, Dr Steve Langron