Power to the people

Developments in consumer electronics over the last few years have thrown up an interesting design challenge. On the one hand, we have consumers wanting more 'bells and whistles' in the products they buy. Not only that, they want those products to be smaller and for their battery operating life to be longer. Responding to these requirements, semiconductor developers have taken advantage of the latest process technologies to produce chips which go some way to meeting the consumer's needs; certainly in terms of reduced power consumption and, hence, longer operating life. But what may be seen as the weak link in this process is the battery itself. Despite much work, battery technology has not advanced significantly of late. The challenge for battery developers is power density; the greater the power density, the smaller the battery can be made for the same capacity. In the long term, it is expected that fuel cells will take over from the Li ion or NiCd batteries to which we have become accustomed. But fuel cells for portable devices are still some way off and there is a school of thought which says fuel cells may never be developed to the point where they can be primary power sources for consumer devices. Instead, they may become the favoured method for recharging batteries. However, work at the University of St Andrews may be changing all that. Researchers have developed an approach – called the St Andrews Air cell, or STAIR – in which the battery draws oxygen from the air using porous carbon. The researchers believe it may be possible to create a battery with 'five to ten times' current storage capacities. Smaller batteries will, inevitably, lead to smaller products and enable completely new approaches. Will this mean 'power to the people'?