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Silicon Supercapacitor Promises Built-in Energy Storage For Electronic Devices
Science_afficionado writes "A news release from Vanderbilt University begins, 'Solar cells that produce electricity 24/7, not just when the sun is shining. Mobile phones with built-in power cells that recharge in seconds and work for weeks between charges. These are just two of the possibilities raised by a novel supercapacitor design invented by material scientists ... that is described in a paper published in the Oct. 22 issue of the journal Scientific Reports. It is the first supercapacitor that is made out of silicon so it can be built into a silicon chip along with the microelectronic circuitry that it powers. In fact, it should be possible to construct these power cells out of the excess silicon that exists in the current generation of solar cells, sensors, mobile phones and a variety of other electromechanical devices, providing a considerable cost savings. ... Instead of storing energy in chemical reactions the way batteries do, “supercaps” store electricity by assembling ions on the surface of a porous material. As a result, they tend to charge and discharge in minutes, instead of hours, and operate for a few million cycles, instead of a few thousand cycles like batteries.' The full academic paper is available online."
Call me when a supercap has anything like the energy density - by any measure of cubic or weight - as a battery. Till then, they have only niche uses. I've seen various supercap articles that were about tech that was "About to change the world" for how many decades now? OK, sooner or later, they might...I'm still waiting, and I ain't gonna live for as many more decades as I've already been waiting. Till then, I'll drive my Volt.
Why guess when you can know? Measure!
to provide electricity for my flying car, and my holographic storage disks too!
If I read the article correctly, this would allow supercap batteries to be placed on the chip die. This doesn't sound like much, but it would be useful in keeping DRAM refreshed if there is a power outage for a brief bit, or enough juice to dump the DRAM to permanent storage (a small SSD.) If the processor state can be saved as well, this would allow a computer to start right back up almost exactly where it was before.
Of course, this wouldn't be enough power to keep a modern day CPU like a POWER7 running at full tilt for any significant length of time, but it might be enough to get the machine's components to save its state and shut down cleanly.
Then, there are the obvious uses for supercap batteries. A buffer for solar cells that can charge the regular batteries at exactly the power they need is one example, especially if combined with a MPPT controller. If the supercap cells are good enough with energy density, they could even be the primary batteries, although there was a patent application with working prototypes I read mentioned a bit ago [1] about high temperature batteries with a large energy density, and these would be a great candidate as primaries, while the supercaps would be additional storage, a buffer for optimal charging, and giving the ability to continue charging for a little bit of time once the solar panels stop receiving usable light.
[1]: http://arxiv.org/ftp/arxiv/papers/1307/1307.1305.pdf
The thing is, there are many applications where space and weight aren't an issue, but lifetime and power sourcing are. For instance, I have lots of room -- going ten X on the space involved isn't a problem for me in any way, but it'd be awesome to have a reliable, high-power capable storage system to replace the batteries I'm using now, which (a) aren't going to last very long and (b) are severely limited by comparison in terms of the maximum current that can be drawn from them.
The real problem is just an engineering one: we need some standard systems to give us usable energy in standard ranges (12vdc and/or 120/240vac) from ultracap stacks. There's nothing hard about that, it's a market and demand issue, no more. Given the demand, designing the hardware is a doddle.
And of course it's worth noting that UC size is going down while power is going up. Most likely, at some point they will cross the battery line, and that's the time to buy stock in whatever UC company pulls it off.
Plus, instead of poisoning the environment with a dead battery, you can will your UCs to your kids. :)
I've fallen off your lawn, and I can't get up.
The purpose is science, so we know how things work and what we can do. Technology you can personally leverage comes later. ALWAYS. You think the transistors on the ICs, and the ICs themselves, sprung into being in the first microprocessor systems? No, they were lab critters and no more than that, well prior to the 4004 and successors. Crude, hacky looking things of no direct use to anyone. But now look at them.
I agree it's tantalizing to see and hear about such tech and not be able to use it, but this is the process, and there is no alternative that's obvious to me, nor apparently, anyone else.
I've fallen off your lawn, and I can't get up.
I hate that kind of consumer mentality - it actually gets in the way of any sort of progress.
In fact, it should be possible to construct these power cells out of the excess silicon that exists in the current generation of solar cells, sensors, mobile phones and a variety of other electromechanical devices..
Not sure if they're making a comparison here or proposing an application, but wouldn't it be pretty spiffy if you had photovoltaic cells that stored the energy they collect and convert from sunlight, so it's there to use when you need it? Not sure what the leakage factor for a supercap of this type would be compared to current technology supercaps, you'd still have some energy stored for an hour or two at least, and I think that would be a game-changer for solar power.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!