For all those who still waiting for practical fuel cells for their gadgets, Sony has developed a new technology that it says could help produce the world's most efficient DMFC (direct methanol fuel cell) yet.
While a prototype won't be coming until next year, Sony has developed a film that uses buckyballs (Fullerenes) that should help fuel cells reach a power density of about 100 milliwatt-hours per square centimeter.
The formula Sony has developed uses the buckyballs arranged in clumps of eight. Sony is mixing them in a polymer to form a barrier that makes for thinner membranes. The goo helps stop the penetration of oxygen across the fuel cell's membrane and stops methanol leakage, which in turn boosts the power density...or so the Sony boffins say.
The company is understandably cautious about when it can start making DMFCs and won't say how long its going to be before the film slips into DMFCs and the DFMCs slip into products. But, according to Sony's Yuriko Nakatani, the technology looks like a significant step in the right direction towards the development of DMFCs powerful enough to supplement or replace lithium batteries for handheld gadgets.
Methanol leakage and power output have been the devilish details that have stopped DMFCs becoming widespread, along with regulations that are still being hammered out to allow methanol to be carried aboard passenger planes, and a methanol fuel infrastructure, i.e. being able to pick up refills at Japan's ubiquitous conbini (convenience stores) for example.
Breakthroughs with DMFCs are announced regularly in Japan, Canon
being the most recent. A number of companies have announced advances with DMFCs for portable gadgets, particularly Hitachi
, NEC, Samsung
and Fujitsu. This year's Ceatec show, as we highlighted before, demonstrated that progress continues to be made.
The flip side of this is that while there have been lots of claims of breakthroughs and almost as many delays in commercialization. A few years back NEC claimed it had reached a then-highest power density of 100 milliwatts per square centimeter using an exotic DMFC design based on the company's carbon nanohorn technology, but had to pull back on its long cherished dreams of commercializing the technology.
Sony believes that 100 milliwatts is the start line for power density but others, notably the boffins at NTT think this is far too low. So the bottom line is we don't expect miracle battery replacements from Sony soon.