An innovative design for a 'twirling' battery could help get you out of a fix the next time your mobile runs out of juice, although sadly the team behind it has yet to produce a working prototype.

The design, developed by Song Teaho and Hyejin Lee and showcased over on design.fr - via Engadget - uses an in-built generator to provide a quick boost of power when the unit is twirled around the user's finger.

Providing around two minutes of talk time for a hundred and thirty twirls - which shouldn't take too long to complete - the system is designed to provide a way of getting power to the mobile for a last call, such as when you need a taxi after a long night out. Alternatively, if you're waiting for an important text, a hundred and thirty twirls will get you around twenty five minutes of standby time.

While the design isn't quite as tidy as competing innovations - such as Nokia's plans to create an energy harvesting handset that would never need charging - it's a neat solution to the problem of finite battery life, and certainly better than carrying around a bulky 'emergency charger.'

There are some disadvantages to the design, of course: it requires that the user take the battery out of the 'phone in order to charge it - something which could be a challenge after a particularly drink-filled evening out - and by its nature is rather more suited to charging small devices such as mobile handsets than higher draw devices like laptops. Despite this, it's an interesting design - and one which the pair hope to be able to bring to production.

Are you impressed by the thought that's gone into the battery, or are you struggling to imagine being desperate enough for a two minute call to dismantle your handset and twirl the battery around like a lunatic? Share your thoughts over in the forums.