Five cool battery inventions that could change modern life forever
By Rachel England Wednesday 27 March 2013
Imagine trying to get through the day without using a battery. There’d be no mobile phones for a start, or portable computers of any kind. You’d have to cycle to work since there’d be nothing to power your car or the bus, and when you finally got to slumping on the sofa in the evening you’d be faced with the prospect of a night getting up and down changing the TV channel manually. Unthinkable!
Modern life as we know it owes a lot to the humble battery, the first incarnation of which came about in 1800. From the cumbersome monsters used in cars to the tiny lithium dots in watches, batteries are an integral part of our lives and have three main components: two electrodes (the positive anode and the negative cathode) and a medium called an electrolyte, which allows positively charged ions to move between the electrodes in balance with the flow of negatively charged electrons – this is the ‘useful current’, or the battery’s ‘zap’, for want of a better term.
The batteries we know and love are usually little cylindrical AA types – the kind that power TV remotes and cameras. Alas, as crucial as they’ve been to technological evolution, they’re not so great for the environment; they’re difficult and dangerous to get rid of, and their disposable nature means they’re pretty wasteful, too. But like all things in these techy times, plans are afoot to make batteries slimmer, cheaper, more efficient and better for the environment. Check out these five cool developments.
The potential of graphene batteries was discovered after researchers at the University of California, Los Angeles, coated a disc with a layer of graphite oxide and then zapped it under their DVD burner. Then, by a stroke of luck, they happened to discover that the resulting material is capable of holding a charge. Talk about a lucky accident! And it’s not just any kind of charge. The researchers reckon an iPhone powered by a graphene super capacitor could charge in just five seconds! Better still, it has zero environmental impact as it’s biodegradable and compostable.
First things first, water and batteries are not usually a good mix, namely because the reaction between water and lithium – the metal prominent in modern batteries today – is pretty shocking. However, scientists have found a way to pair the two to create impressive energy densities (the amount of energy that can be stored in a battery) in a single unit, while also doing away with the need for a positive electrode, meaning these batteries could be lighter and cheaper to produce. It also looks like they’ll boast long lifetimes, so the invention will probably be aimed at the marine market, for underwater robots and vehicles.
After the trusty AA or AAA battery, rechargeable lithium-ion batteries are usually our go-to energy source, responsible for powering mobile devices such as phones and tablet computers. The problem with these, as anyone who experiences battery drain on a regular basis will know, is that they don’t really last very long, and smartphone addicts can struggle to get through the day without hooking up their device to a charger. So scientists set about looking for an alternative, and came up with lithium-air batteries, where oxygen is used as a catalyst for exchanging electrons. And boy, do they address the battery-life issue. Whereas a regular lithium-ion battery has a capacity of around 200 watt-hours per kilogramme (Wh/kg), a lithium-air battery stores up to 3460Wh/kg.
The problem with these is that the chemistry involved is bafflingly complicated, so researchers are now looking at sodium-air batteries, which have a capacity of 1600Wh/kg. Not as good as lithium-air, but a heck of a lot more impressive than the standard lithium-ion fare. Unfortunately, these experimental batteries can only be charged around eight times before dying forever, so it’ll be low battery warnings all round until scientists sort that out.
It sounds like something from The Matrix, but bendable, twistable batteries are set to take the market by storm, opening up a whole world of new designs and inventions for traditionally square electronics such as mobile phones and e-readers. Thanks to a team of scientists from South Korea, who have developed a high performance, flexible lithium-ion battery using super-thin film, it’s only a matter of time before we can fold or roll up our gadgets on the go.
Think about it, nothing on Earth simultaneously creates and uses energy quite like a human being! In fact, the average person gives off 100 watts of excess energy just by standing around, and stores as much energy in fat as a one-tonne battery.
Scientists around the world are already making the most of this ‘ambient’ energy, with more plans afoot. In Paris, architects have combined it with wheel friction from a Metro station to supply heat to 17 apartments in a nearby public housing project, and in Stockholm’s Central Station, travellers are pooling their ambient warmth to heat a 13-storey office block. Just think what could be done with the excess energy from all six billion of us!