The technology, which uses hydrogen to generate power, has been installed in a MOTOSLVR L7 phone without changing the size or shape of the handset.
Angstrom claimed that the fuel cell lasts twice as long as an equivalent sized lithium battery, and recharges in just 10 minutes.
Stuart Robinson, director of handset component technologies at Strategy Analytics, maintained that the development of lithium batteries is too slow to meet the growing energy demands of cellular handsets.
"Our research shows that insufficient battery time is one of the leading considerations in the adoption of handheld devices with rich multimedia functionality," he said.
"Angstrom's achievement, the world's first successful integration of micro fuel cell technology into a standard mobile handset, demonstrates the potential of such cells to provide a better solution for demanding mobile energy applications."
The potential market for the fuel cells is huge, but Angstrom's existing relationship with Motorola means that company is likely to get the technology first.
"As consumer demand for smartphones and multimedia devices grows, so does the need for power solutions that enable 'always on' experiences," said Jerry Hallmark, manager of energy system technologies at Motorola's mobile devices business.
"Motorola is working with Angstrom to develop fuel cell technology that will support the increasing energy demands of next generation devices."
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