Attempting to be greener these days can sometimes prove to be difficult; especially when functionality or aesthetics on a handset are compromised to accommodate such things. The concept of using another electrical source to charge a cell phone battery has long been adopted by manufacturers – which doesn’t seem to end in the near future. Every now and then, they throw at us some other practical way of charging a phone – such as wireless inductive charging for example. Fortunately though, one new battery concept aims to mend green technology with a unique twist in the way it gets charged. Designed by Song Teaho and Hyejin Lee, this concept borrows from those wind-up gadgets that allow them to function/charge by simply rotating a crank to get some juice. There isn’t a prototype available yet, but it involves you in twirling the battery around your finger to get it charged – no electrical source required; it’s all natural and powered by your finger. Designers estimate that 130 twirls will provide roughly two minutes of talking time. At that rate, it would take quite some time to get a decent level of power to make a solid ten minute phone call – still it’s human powered and does not require any other electrical source. Just make sure that your finger is in shape if this concept ends up becoming reality.