Turning hydrogen into juice for your phone is as eco-friendly as it gets, but our pictures show the big problem with the Upp fuel cell charger.
The Upp comes in two parts: the hydrogen cartridge on the left and the charger on the right.
The Upp fuel cell charger converts hydrogen to elecricity for your phone. It's eco-friendly and comes with a clever app that should point the way for all phones, but it has a few problems too.
Here you can see how big the Upp is, which isn't ideal.
Despite being designed for travel or camping when you're away from mains power, the Upp is far from portable.
The two snap together to form the charger.
The only by-products of this environmentally friendly device are heat and water vapour, which is vented from the charger.
The charger is about the size and weight of a sturdy torch.
The Upp charges most devices with a USB connection.
The charger comes with a clever app that allows you to fine-tune the charging process. In the left-hand screenshot you can see the remaining power in both the charger and your phone, and on the right you can see stats on the battery.
The hydrogen cartridge attaches magnetically to the charger. The hydrogen cartridges can be refilled but must be exchanged for new ones, which isn't cheap, at £10 (around $17).
Although eco-friendly fuel cells are a great idea and definitely a technology to watch, in this case the Upp is just too cumbersome and expensive.
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