Robert F. Service's article on progress in developing miniature fuel cells for powering small electronic devices (“Shrinking fuel cells promise power in your pocket,” News Focus, 17 May, p. [1222][1]) is interesting and encouraging from the point of view of alternate energy strategies, but I wonder if the technology described is not already obsolete. Workable miniature fuel cells are coming on the market ([1][2]). The definition of a “fuel cell” should include not only cells using hydrogen and methanol, but also metal air cells. These are often called batteries, but they are not merely electricity-storing devices. Aluminum is especially interesting because the oxidation of aluminum produces enormous amounts of energy. To extract this energy in the usable form of electricity, aluminum is oxidized in an alkaline environment to aluminum hydroxide ([2][3]). Some of the more difficult problems of miniaturizing this technology have now been overcome ([3][4]). The Trimol Group is bringing out a unit 60 mm by 35 mm by 8 mm in size, which can power a wireless telephone for 25 hours of continuous talk ([1][2]). However depressing that prospect may be for the parents of teenagers, the problem of miniaturization of fuel cells has been solved.
1. [↵][5]See [www.trimolgroup.com/product_cellphone.htm][6].
2. [↵][7]See [www.aluminum-power.com/technology.htm][8].
3. [↵][9]See [fuelcell-magazine.com/articles/april101-2.htm][10].
[1]: /lookup/doi/10.1126/science.296.5571.1222
[2]: #ref-1
[3]: #ref-2
[4]: #ref-3
[5]: #xref-ref-1-1 "View reference 1 in text"
[6]: http://www.trimolgroup.com/product_cellphone.htm
[7]: #xref-ref-2-1 "View reference 2 in text"
[8]: http://www.aluminum-power.com/technology.htm
[9]: #xref-ref-3-1 "View reference 3 in text"
[10]: http://fuelcell-magazine.com/articles/april01-2.htm
