Sydney, Australia-based technology developer CAP-XX (CPX:AIM) is small. Very small. It's currently valued at £6.6 million, and that's after today's 8% share price hike to 7.62p. It designs and makes thin, prismatic supercapacitors that are used to maximise energy efficiency in electronic devices.

This is cutting edge stuff, and forward-thinking. Ecologically we are all being urged to use less energy to relieve the strain on limited natural resources. Yet at the same time, our need for electricity to power the ever growing number of electronics we use is rising by the day, particularly mobile devices for our increasingly on-the-go lives. So extending the life of battery power is a worthwhile ambition, one that CAP-XX is trying to meet.

Good news then that the company has successfully completed trials of its 'Stop-Start Automotive Supercapacitor Module' with Club Assist, a leading worldwide provider of roadside breakdown assistance support for motoring clubs. The hope is clearly that this is the latest stepping stone on the way to commercial deals with electric car manufacturers, clipping the wings of 'range anxiety' that some fear. It's perhaps a bit surprising since the company's own website states: 'CAP-XX is not currently pursuing automotive engagements but will continue to evaluate this market as industry research progresses.'

Anyway, it's understandable that the shares should rise, no? Well, not quite. You see, that announcement was made two days ago. Now today, the shares are on the rise, possibly because barely anybody had previously noted the company's newsflow earlier. And even so, today's rise comes on razor-thin volumes (on a near 10% bid/offer spread, can you blame them). According to my data, just 1,873 shares have changed hands, or £150 worth. That's moving the market for the price of a decent meal.

CAP-XX - Comparison Line Chart (Rebased to first)

So investors beware, microcaps can offer exciting growth potential at bargain prices missed by most in the market. But they can also leave your trading account battered and bruised on the merest touch. Do your own research, as is often said.

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Issue Date: 05 Apr 2013