P21 GmbH - The P21 fuel cell

Requirements.

P21 is the product of basic research conducted by a group at Vodafone (formerly the Mobile Communications Division at Mannesmann) for the use of fuel cell technology for mobile telecommunications. The group focused on the development of a fuel-cell optimized for use in base stations for mobile communication. P21 thus developed its PEM fuel cell especially for use in base stations for mobile communication.

Wide temperature range

Premion T can be operated in all kinds of climates. At the same time, it reduces the energy needed for active heating and cooling.

Compact and light

P21 's fuel-cell system only weighs 93 kg. It can be housed in a standard 19-inch rack or installed as a standalone unit outside of a base station.

Double-layer capacitors for uninterrupted operation

Double-layer capacitors cover the few seconds needed for the fuel-cell stack to start. The result: uninterrupted power supply from the first second.

Voltage range in accordance with ETSI standard

The fuel-cell stack provides power in the range standardized by ETSI. No DC/DC converter is required. This approach increases system efficiency considerably.

System management

The fuel-cell management system can be fully integrated in the mobile communication network operator's current network management system.

Safety from start to finish

Hydrogen is stored at 350 mbar. This simplifies the supply of hydrogen and increases safety.
The stacks are separated from the other parts of the fuel-cell system with no air exchange. The stack receives sufficient ambient air.
The control system is redundantly monitored. The system constantly monitors the operating parameters and compares the values with figures from a database. Both units receive the values independently. If the figures fall outside of the target range or the two units tally different results, the system is switched off.
To hydrogen valves control the flow of hydrogen: one outside of the hydrogen tank; the second, directly inside the fuel cell. The valves close if there is no pressure.