While our gadgets these days are constantly getting smaller and more powerful, the development of commercial batteries both small enough and with sufficient capacity to feed their power-hungry demands has not quite kept pace.
Most people will have heard of Lithium-ion (Li-ion) batteries. They’re in almost all mobile electronic devices – from your mobile phone and laptop, through to back-up power supplies on jets and even spacecraft. Surprisingly though, despite this huge demand, the fundamental design of Li-ion batteries has remained broadly similar in recent years.
Battery life is frequently the constraining factor in many existing and experimental applications. It’s key for the future of technologies such as electric cars, and for high-capacity energy storage for renewables such as wind and solar power. In fact the comparatively slow progress with developing new batteries has resulted in many electronics manufacturers turning to trying to reduce or maintain their products’ power requirements to find a balance.
Which is not to say that there’s no research into new energy storage techniques. Far from it in fact. The past few decades have seen an explosion of research in this area. Unsurprisingly, a good deal of this revolves around improving Li-ion batteries. The new “wonder material” graphene has also been suggested as a possible key to the solution. Graphene has a number of interesting properties that have led researchers to suggest either modifying components of Li-ion batteries, or using graphene as the energy-storage medium instead as promising solutions.
Just Add Graphene
Graphene has also been used to develop electronic devices with extremely low power requirements. This is possible (in part) because pure graphene has the lowest resistivity of any known material at room temperature – devices made of pure graphene can conduct electricity more efficiently than any other material (at room temperature). As a consequence, very little energy is wasted.
Devices built with graphene would not experience the same problems of heating faced by current electronics – they could run indefinitely with very little increase in temperature. Heat is bad for electronics; it means energy is being wasted and it often serves to reduce the efficiency of the device further as it heats up. Pure graphene virtually eliminates energy losses of this kind, which makes devices produced from it extremely energy-efficient. For consumer electronics, this could mean significantly more powerful devices with massively improved battery life – a win-win scenario if ever there was one.
What’s more, studies indicate that using graphene to replace or enhance components of Li-ion batteries can significantly improve the energy density and longevity of the battery. One popular technique has been to make the anodes or cathodes in Li-ion batteries out of graphene.
