Safety and legality aside, could you design a phone that never needed to be charged?

[Tommygun]

I had forgotten about the Army's solution to this.

Eventually the whole generator would have fit inside the shoe.

You recharge while walking.

It may have been cancelled though?

http://www.designnews.com/author.asp?doc_id=235935

[jwenting]

The battery life in current phones could easily be extended hugely. Increase the battery size and radically reduce the power draw of the phone. Never charge might be some years away, but I'd guess a charge a month is plausible.

Of course, that means a heavy, dumb phone. Few people will buy it. People grumble about smartphone battery life, but they'll still pick the fast chip and the bright glossy screen every time. Meanwhile the chip's speed goes to waste running ever more inefficient code, and the display is worse in bright conditions than a matte e-ink display could be.

I'd buy another original Nokia 6110 (the purplish blue one) if I could. It's a phone, not a pocket computer, it's all I need.

Only reason I bought a smartphone was because it was cheaper, smaller, and had longer charge life (with most of the "smart" stuff turned off, I don't use it anyway) than a decent normal cellphone...

[Seret]

It may have been cancelled though?

Likely to be highly unpopular with the troops.

[shynung]

Really? My iPhone is over 2 years old, and it's not even damaged or slow

People typically buy a new phone every 18 months or so. The old phone doesn't have to be damaged or unusable, merely outdated is enough. There are exceptions, however, on both sides; some people change their phones every few months, some don't do it for years.

Edited June 3, 2014 by shynung

[lajoswinkler]

Of course, let's check how much... 15 kg of U-233??? Yeah, not happening.

Where do people get the idea that Th-232/U-233 will solve everything? It can be a bit better than U-238/Pu-239, but the later at least is a parallel reaction in U-235 reactors that is taken advantage of. Did someone launch "uranium - bad, thorium - good" propaganda? (I actually like the idea of the breeder reactor, because more abundant and cheaper fuel is always better, but some things said about it, as with many of new tech propositions, sound much like "there are much less costs and problems... we are aware of...")

Anyway, if someone makes this as power source for a car I'm not sitting in it. I'm okay with idea of RTG-powered car (at least you can know what it radiates and what is the required shielding), but a fission reactor is something that needs much more protection.

There is a crooked campaign by some individuals online, indeed. It's powered by hype and the need to be different, very closely related to quack population.

Thorium has its own advantages and disadvantages over uranium, and "they wanted uranium because of bombs!" is not the sole or the most important reason behind the fact we use uranium.

And RTG... that will never enter general citizen application. It would be a radiological disaster waiting to happen even if it was cheap enough, and it's far from cheap.

Anybody knows the watches without batteries that charge by the movement of your hand?

Scale up the technology and put it into a mobile phone. Voila. As long as you carry it with you it will get charged by your movement. Sure the phone would be heavy but who cares, it's free energy

Another option: anybody knows the pocket lamps that can be charged by pressing a lever all the time, put that tech into a mobile phone and you can charge it by hand.

Damn i am a genius

The problem is - you can't scale it. A digital quartz watch consumes extremely small amounts of energy compared to a smartphone. So... it's not genius. It's *genius*

Those levers and stuff like that... nope. Too weak.

No not a good idea for several reasone mentioned, we will need to produce 0.5 watts electric continously for years, an RTG does about 5% efficency so that a 20 Watt heat source.

1. Several thousand dollars a gram, at least 20 grams needed.

2. How to pump out the waste heat, the hot side alone will be above 800C

3. The low levels of neutron emission and gamma rays from daughter product decay and random neutron fission.

It would not heat to those temperatures. The only reason you see those photos of incadescent pieces is because they were testing them. Scientists would cover the pieces with a thermal insulator and wait for quite some time (hours, probably) until the heat would build up sufficiently to cause glowing.

You'd have to remove the heat in order to make it efficient, but it would not be very hot under normal handling. It would be warm to the touch.

Edited June 3, 2014 by lajoswinkler

[Nuke]

i came up with another idea, what about those little engine on a chip devices? you know where you have a small mems turbine generator running on some kind of hydrocarbon fuel. obviously using a carbon based fuel would have its issues, but what about h2o2. your exhaust is water vapor, and oxygen. such a device would be packaged with a fuel reservoir that would last several years. of course such devices need to handle the water vapor in the exhaust so it stays out of the electronics, but i think its something that might be plausible for low power devices.

[lajoswinkler]

i came up with another idea, what about those little engine on a chip devices? you know where you have a small mems turbine generator running on some kind of hydrocarbon fuel. obviously using a carbon based fuel would have its issues, but what about h2o2. your exhaust is water vapor, and oxygen. such a device would be packaged with a fuel reservoir that would last several years. of course such devices need to handle the water vapor in the exhaust so it stays out of the electronics, but i think its something that might be plausible for low power devices.

Not nearly enough energy. Just look at the energy hogs our phones have become. You need to charge them every day if you use them often. I'm seriously considering buying a solar charger for mine, because I don't want to stay stranded somewhere. You can't go on a one day trip into the wilderness with these phones. They're a disaster.

[Nuke]

you obviously aren't going to get top notch performance out of a smart phone running on a pseudo-eternal battery, especially when they keep trying to get higher cpu performance into them. that does not exclude the possibility of such devices if you can accept reduced performance. if you can handle that, and can wait for the process size to come down a little bit more, you can get the power requirements down as well. this year a phone's cpu might use 10 watts, few years from now maybe 1 watt and so on until we hit the process wall (where making the process smaller is physically impossible). miniscule process size plus low power architecture and you might have a chip you can run on a betavoltaic device or a micro-engine.

thats just the cpu though. transmit and receive still cost some power. running a screen costs power. so a smart phone as we know it wont work on such a power supply. i kinda envision a device that would use an e-paper display and would allow you to send and receive text messages using low bandwidth burst transmissions. it would be of such minimal impact to cell networks that service would be free. the devices themselves would be dirt cheap and globally available. oh, and you never have to pack a charger.

Edited June 3, 2014 by Nuke

[phoenix_ca]

Not nearly enough energy. Just look at the energy hogs our phones have become. You need to charge them every day if you use them often. I'm seriously considering buying a solar charger for mine, because I don't want to stay stranded somewhere. You can't go on a one day trip into the wilderness with these phones. They're a disaster.

Disaster might be an over-statement. They are, like so much else in our society, dependant on our technological advancement. You already pointed-out the solution to your problem: Get solar panels.

If you expected the military to use these things for mission-critical operations, then yes, you could call that a "disaster", because one day of use is just absurd. But we're talking about civil applications here.

In any case, graphene circuits for some components could be a solution to the efficiency problem. Graphene is ridiculously efficient and has already been tested successfully for use in a cell phone transceiver. http://ibmresearchnews.blogspot.ca/2014/01/graphene-circuit-ready-for-wireless.html

Edited June 3, 2014 by phoenix_ca

[lajoswinkler]

Nuke, the e-paper idea, that's convenient. How much power does a simple Kindle have? I still think it would be too weak. This is microwatts you're talking about.

phoenix_ca, it's a disaster if you're out in the wild, in the mountains, and your phone dies. Cold wind, bears... gosh.

My old phone could go on standby for like 5 days or more. I really need a solar charger.

[phoenix_ca]

Actually the e-paper idea is a very good one (though more specifically reflective displays over transmissive ones). By a very wide margin, the largest power drain on a smartphone is from its transmissive display. The same thing goes for laptops. Reduce the power consumption of that display, and you can have devices with stand-by times measured in months. If you were able to replace a smartphone display with a reflective display with similar performance to a transmissive LCD one (and a backlight for low-light environments), then the same-sized battery would last much, much longer. The main issue is getting a display to respond fast enough. It's being worked-on by plenty of companies but so far I haven't seen anything that came close to the roughly 6ms response time of an IPS LCD display. :/

phoenix_ca, it's a disaster if you're out in the wild, in the mountains, and your phone dies. Cold wind, bears... gosh.

Well...I'd hope that you wouldn't bring a cell phone with you to the wild. A purpose-built radio would be a far, far better idea, so that you can, you know, actually transmit on frequencies that rescue services are listening to. O.o (It's quite literally in every survival guide worth reading. Bring a radio. Know how to use said radio. Be prepared to lose said radio, or use its battery for fire as a last resort. Etc. etc.)

[andrewas]

If you're going into the wild, you take equipment better suited for those conditions. Rather than a smartphone, take a £10 dumb phone. Its not like a smartphone is very useful out there anyway. The only useful functions I can think of are the camera and the map service. You'll get much better pictures if you take a proper camera, phone cameras all have crap optics even if they have a decent sensor. And the map service is a luxury, bring paper maps and learn to use them, don't ever depend on fallible technology for something as simple as figuring out which direction you need to go.

[Nuke]

the point of an e-paper display is that it only costs power to flip a pixel. it doesn't cost any power to maintain an image, unlike most other displays. it also isnt going to be a very big display, a few lines of characters at most. its also going to have a really slow refresh. the whole device is spending most of its time sleeping, while its sleeping any unused power is used to build up charge in capacitors. when it needs to wake up, it uses the stored charge and goes back to sleep before they run low. you push a button, and the thing might wake up for a millisecond to register the action and go back to sleep. the greatest power hog will be the radio. transmissions will need to start and end without completely discharging the buffer caps. somehow you will also need to detect incoming transmission and wake up the device to receive them, this will require some standby power. a 1 micro-watt power supply (there are betavoltaic devices that can do that) could run this thing, but it wont be a very fun gadget to use. but humans seem to be easily obsessed about gadgets with horrible interfaces.

now with advancements in both low power electronics and improved betavoltaics, who knows how far you can take it in the future.

Edited June 4, 2014 by Nuke

[lajoswinkler]

If you're going into the wild, you take equipment better suited for those conditions. Rather than a smartphone, take a £10 dumb phone. Its not like a smartphone is very useful out there anyway. The only useful functions I can think of are the camera and the map service. You'll get much better pictures if you take a proper camera, phone cameras all have crap optics even if they have a decent sensor. And the map service is a luxury, bring paper maps and learn to use them, don't ever depend on fallible technology for something as simple as figuring out which direction you need to go.

But I wouldn't have Flappy Bird.

Back to the topic, betavoltaics couldn't power a cell phone which could be used for voice communication. Bursts could enable textual communication only. But that's enough. It would be a lifesaver in certain situations.

Edited June 4, 2014 by lajoswinkler

[Nuke]

makes me wonder if the problems with betavoltaics can be solved. the problem comes from the fact that beta particles that are too energetic can destroy the semiconductor material that is needed for the device to operate, which limits them to very low power applications. i found this article:

https://rt.grc.nasa.gov/power-in-space-propulsion/photovoltaics-power-technologies/technology-thrusts/alpha-and-beta-voltaics/

they kinda improve the device by using a photovoltaic configuration with a phosphorous layer. instead of applying the alpha/beta particles directly to the semiconductor, they add a layer of phosphorous which converts the radiation to light, the light then is used to generate power with a rad hard photovoltaic device. these will be able to get up to about 5 milliwatts, which is a huge improvement over previous devices.