Remember the quick-to-run-out batteries that powered the toys of your youth? The ones that eventually leaked and wrecked your precious stuff? They've largely been banished by years of battery tech innovations that have made batteries longer lasting. But even our cleverest battery tech may be a huge weakness in Internet of Things devices, especially if we're going to be embedding them in wallpaper, burying them in plant pots, or sticking them in the labels of supermarket products.
But there are, somewhat fabulously, some very clever innovations underway to get around this problem.
For starters, check out this innovation by scientists at Penn State and Rice University: The teams have worked out a way to make solar cells based on organic chemistry, which could lead to fantastically cheap and actually bendy solar power systems.
When you think of a solar cell, you're probably visualizing a large(ish), solid shiny gray object that's bulky, heavy and yet quite probably too fragile to drop. That's because typical solar cells are based on inorganic crystalline silicon, which is hard and somewhat glass-like to touch. Making them is tricky, expensive and requires precision.
A better solution is to use organic molecules to construct solar cells, because these can potentially be made more simply, requiring less precision and even cost. But there's not too much research into organic chemistry solar cells, since everyone's trying to make inorganic ones more efficient. And the systems that exist to produce organic solar cells tend to require some wicked chemical tricks with fullerene—an exotic carbon variant that's said to make it very hard to scale up for mass production.
So the Penn State and Rice researchers simply sidestepped using fullerene. Instead they have devised a way to get all the complex strings of organic molecules that would make up a solar cell to more or less assemble themselves into the right structure automatically. The trick has been to adjust the shape of the molecules in question carefully, so that when they're turned into a form of plastic they align by themselves and create a brand new way to capture solar power.
But, critically for the Internet of Things, the molecular design can be improved upon, and it's said to be easy to scale up for mass production...as well as being very cheap. This means that soon enough it should be possible to cover walls, windows, and perhaps sticky labels or even Band-Aids with tiny, flexible solar cells to power the wireless systems, processors, and sensors we're going to embed into them.
Failing that, a separate innovation from the University of Massachusetts and the University of Washington does away with the need for a battery altogether. The teams have invented a new type of e-paper display that gets its power completely wirelessly, and only when it's needed.
The trick has been to combine e-paper display technology, which only needs a jolt of electricity when, for example, the color of a pixel is being switched from showing white all the time to showing black all the time with NFC tech.
NFC systems operate by sending and receiving wireless signals over very short ranges. In some cases, such as in contactless smart subway tickets, the electronics in the card actually captures energy from the radio signals it's being exposed to by a transmitter—then it uses that electrical energy to briefly power its tiny embedded electronics. The new e-paper innovation, called an NFC WISP E-ink Display Tag, works on a similar principle. Essentially it sucks out more energy from an NFC signal than it needs to process the data signal coming to it, and it uses the surplus to change the pixels of the attached e-paper screen. Considering NFC tech is commonly used in devices like smartphones, this could lead to Internet of Things devices having tiny screens that only update when you need to see them, or other uses like dynamic store shelves or even product labels.
Expect more innovations like this to parallel the Net of Things revolution because they'll see wireless tech and smart sensors embedded in places you'd never want to stick a battery.
[Image via Flickr user: JD Hancock]