If you thought battery technology was already good enough to power these new quad-core smart devices with big screens and high-resolution Retina displays, you ain't seen nothing yet.

A research time at Rice University, Texas have demonstrated lithium-ion batteries created using a spray painting technique. This new tech would be perfect for creating batteries within areas that it might be difficult to fit a standard power cell.

This would open up an entire world of possibilities, where batteries could even become part of the structure of the device itself, or be spray-painted onto a car for example. The technology could also go hand-in-hand with solar cells, which sport larger surface areas meaning there's an opportunity to paint a larger battery in a layer beneath them.

The spray-on battery is made by taking the traditional ingredients of a lithium-ion battery and making them into a liquid form that can be sprayed layer-by-layer to make the working battery. The liquefying process currently uses hazardous substances, and is expensive but the team are working on finding other chemical possibilities.