In situ H2 supply technology for micro fuel cells
Two novel solutions are proposed for fuelling micro fuel cells in which hydrogen is stored in a chemical form in a primary fuel and released in-situ on-demand basis. The technical implementation is a hybrid system, where the fuelling unit is combined with hydrogen PEM fuel cell providing the benefits of both the PEM and DMFC technologies. The primary fuel is stored in a disposable or recycled cartridge, which is changeable and logistically easily available. The electrical power is generated in a fuel cell utilizing gaseous hydrogen released on the demand from the cartridge. The system includes a small electrical intermediate storage (accu or super capacitor) and a control system for controlling the power release. Because the gas PEM has a higher volumetric power density its size is more compact than that of corresponding DMFC unit. Compared to metal hydride containers the liquid cartridges can store more energy in the same volume and can be made of lighter materials.
Two different technologies for producing hydrogen in-situ are considered. One is based on using NaBH as the fuel and the other on utilizing catalyzed electrolysis of methanol. The primary application area is fuel cell based power sources of portable electronic appliances (5-20W). The ISH2SUP-project concentrates to research and development of the cartridge technology and the electrical system. Development of micro-fuel cells is not included in the project but commercially available small fuel cells are used. The main practical targets are to prove the feasibility of each fuelling technology and to fulfill the RCS requirements of mobile/portable electronic appliances in consumer markets, and to schemealogistics system for disposable or recyclable cartridges used for fuelling the proposed system.