Wireless Power and the End of the Battery
There was some excitement in the mainstream media last July about the demonstration by US firm Witricity of a wireless power device at the TED Global conference in Oxford, UK.
No-one here has had a close look at this particular product, so we can’t add any insight beyond what’s been reported. What we have seen over the past year though, are all kinds of innovations aimed at the portable power market. There’s huge demand, yet with their limited lifespan and toxic ingredients, existing batteries are not the optimum solution. Many innovators are trying to address this issue, in a variety of ways.
Recently, for example, we’ve examined three companies looking to use various solar power solutions to provide more efficient portable power. And, without going into forbidden detail, not all of them involved plain old conversion of solar energy to electricity via a solar panel. Unencumbered by reliance on Silicon, and overcoming the low energy conversion efficiency levels associated with that approach, these firms have a strong proposition.
Portable power is a multibillion-dollar market in the US alone, and growing at over 5% annually driven by proliferation of pocket electronic devices. Lithium-ion batteries dominate the market at present, but their popularity is projected to reduce as new technology presents renewable alternatives.
Perhaps the most promising alternative at present for a portable, efficient power source is the micro fuel cell. Very rapid innovation is occurring in this area and performance equivalence with Lithium batteries is drawing near as many companies compete to develop smaller, longer lasting components. At present, the cutting-edge micro fuel cell systems have dimensions of a few centimetres with power capabilities comparable to traditional batteries. A recent prototype from Sony has dimensions of 5cm x 3cm and can deliver 1.1Wh from 1cc of methanol, compared to a standard lithium-ion AA battery which stores 3.1Wh.
The point is though, that with the emergence of “wireless power transmission technologies” like the Witricity product, all of these competing concepts will suddenly find themselves targeting a smaller (albeit still very large) market: portable power applications where a mains power source does not exist in close proximity. With wireless power transmission over short distances, portable power sources won’t be required for items like television remote controls. The development in Oxford has crucial implications for home-based battery-reliant systems, and therefore for innovative companies developing portable power alternatives.