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Batteries Continue To Suck
pvt_medic writes "As technology continues to grow, and we see more and more of a shift to portable electronic devices in our daily life, we are still constricted by one simple thing: Batteries. Newsweek has an interesting article about the lack of development in battery technology. 'Ironically, in our headlong rush to create sophisticated untethered computing, the most problematic technology turns out also to be the oldest: those nondescript metal cylinders that never seemed to be included with our Christmas toys.' And for those of you who would like an extensive overview about batteries, ExtremeTech.com has a nice overview."
Here's a recent press release about an alternative to chemical batteries. It's a storage capacitor made of porous carbon. Supposedly can store twice the charge of lead acid batteries, recharge in 1 minute and last indefinitely. Sounds relatively simple.
Fuel cells suck ONLY because no one ever commercialized fuel cells 30 years ago.
Fuel cell technology should have been the next leap forward. But it's taken a long time because most investments in fuel cell has been centered around space applications... where light weight, high-performance electrical power is a requirement.
An incredible amount of fuel cell technology was developed in the 1960s and 1970s for space programs - and when you make money on space programs, the bean counters know that there is no reason (financially) to look at other potential markets. That was simply a sign of the times.
Unfortuantely, now most fuel cell expertise has been lost to the retirement of industry experts. Much of the "innovation" in recent years is merely a rehash of research done 30 or 40 years ago, but forgotten because no one back then had a vision for using fuel cells to replace (terrestrial) batteries.
I contend that many modern fuel cell related ideas and patents are really old ideas that have been rediscovered by a new set of researchers unfamiliar with the developments of the past.
It's like we just lost 30 years of ful cell development... too bad, because if the corporations that originally developed this technology had their shareholders in mind, they'd have a slightly longer vision and would be leaders in a new industry.
130V bulbs last dramatically longer because their filaments run much cooler than 120V bulbs (they have larger and thicker filaments, hence a greater surface area to dissipate heat). This is great for longevity, but it comes at a heavy price in efficiency. The lower filament temperature shifts the bulbs emission spectrum towards the infrared (Planck's Law) reducing the amount of visible light produced. This reduction in efficiency will require more electricity to produce a given amount of light. When all is said and done it takes far fewer resources to make higher temperature bulbs that are more efficient than to keep one long life bulb chugging along. Of course, if resource/energy efficiency is a concern halogen and fluourescent bulbs are far better than any conventional incandescent.
There are also other techniques to increase the longevity of regular bulbs. Since the most likely time for bulb failure occurs at switch on, using a switch that only activates at a zero-crossing of the voltage waveform minimizes the turn-on stress. The inrush current to a cold bulb can be on the order of 10x the running current (an incandescent filament is an extremely non-ohmic load because its resistance varies dramatically with temperature). It's this high current that causes high stress on the filament (the motor effect can cause the filament to twist violently). From what I've read, this technique is often used on navigational beacon lights (these lights also use over-rated bulbs to gain lifetime at the expense of efficiency).
Another technique to minimize turn-on stress is keep the bulb running 'warm', that is to pass enough current to keep the filament at a temperature just below that needed to produce visible light. The relatively high temperature raises the resistance of filament, thus dramatically reducing inrush current. According to some theatre techs that I know, this technique is extensively used in theatre and television where a light failure could ruin a show.