Kraftwerk is the first mobile fuel cell that fits in your pocket and runs on common lighter gas. This sounds not completely new, as for example Toshiba and Sony have developed similar applications for mobile devices in the past. Kraftwerk invented by the eZelleron GmbH, a start-up company based in Dresden, Germany, uses a different fuel cell technology which could be crucial for the success of the gadget.
In general we speak of two different kinds of fuel cells: PEMFC (proton exchange membrane fuel cells) and SOFC (solid oxide fuel cell). The first ones can be operated at lower temperature/pressure ranges, use a special polymer electrolyte membrane and are capable of producing electricity after just a few minutes. The disadvantages of PEMFCs are the need for expensive platinum and that these types of fuel cells can only consume hydrogen or methanol. SOFC have a solid oxide or ceramic electrolyte and offer more fuel flexibility while producing less emissions and offering high efficiency. The problem with these kinds of electrochemical conversion devices are high operating temperatures and the longer start up times which made them not suitable for mobile applications in the past.
After several years of research with SOFCs Sascha Kühn, CEO and inventor of Kraftwerk, made a big step forward building a mini-SOFC which produces electricity after 20 minutes. This technology is now used in the Kraftwerk which was crowd founded on Kickstarter reaching more than $1.5 million (original goal: $500,000). In order to deliver energy from the moment you plug-in your phone into the mobile charger Kraftwerk uses a small buffer battery which is charged constantly while the cell produces electricity.
The device offers 2W of continuous power output, 10W peak power with 5V output voltage and can operate from -15°C up to +55°C outside temperature. To achieve these results Kraftwerk sports an LPG gas tank, USB power outlet, a microtubular metallic fuel cell, the necessary power electronics and control electronicss as well as a micro blower for cooling (see picture below). Astonishingly the fuel cell runs on very cheap standard lighter gas and does only get a little warm on the outside while the cell operates at 800°C on the inside! This sounds dangerous but it isn’t – Kraftwerk is even certified by the FAA (Federal Aviation Administration of the US) and allowed to be carried in the cabin luggage when entering an airplane.
Kraftwerk cutaway view (image: Kraftwerke/Kickstarter)
The core of the whole system is the microtubular metallic fuel cell which converts the gas to energy (see picture below). Kraftwerk states that they are able to produce 20.000 units per day – enough for 4.000 Kraftwerk chargers.
microtubular metallic fuel cell cutaway view (image: Kraftwerke/Kickstarter)
The fascinating high-tech pocket fuel cell can currently be ordered for $109.00 via this link and is available in 3 different colours.
Get an impression on how to use and benefit from the device in the video below: