


Batteries Continue To Suck 605
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."
so then (Score:4, Funny)
Re:so then (Score:3, Funny)
Re:so then (Score:3, Funny)
Monster caps are great, (Score:3, Interesting)
Re:Monster caps are great, (Score:4, Interesting)
Of course our million dollar tanks, at least at this time, were equipped with cheezy aluminum tools. One a buddy of my uncle was tightening the lugs on a battery and crossed both terminals. The tool literally melted and burned in a flash.
Re:so then (Score:5, Interesting)
Don't laugh but nuclear batteries are also feasible mass production artifacts, just no one would want them because they would fuck up the env, so bad idea.
Indeed. In fact, there are quite a few ways of generating nuclear power without building a full blown reactor. The coolest part is that your battery life would be determined by the half-life the the material used as a power source. If they could find a heavy element with a realistic life-span of about 3 years (the average life of a computer), then we'd have a winner on our hands. Plus, the actual amount of radioactive material would be tremendously small (think ounces per hundreds of people). If the waste became a concern, a standard battery slot could be developed so that batteries with longer lives could be manufactured. Those 10+ year batteries could simply be moved from computer to computer over the years.
The real problem is that people freak when you use the words "nuclear" or "radioactive". Maybe we should call them "magic" batteries?
What about all the advances? (Score:3, Insightful)
Re:What about all the advances? (Score:3, Funny)
-B
Re:What about all the advances? (Score:5, Interesting)
Re:What about all the advances? (Score:4, Informative)
Maybe I've just grown overly cautious in my old age, but if it can be charged quickly, it must capable of discharging quickly, no? Energy-storage devices of reasonable density that can discharge very quickly make me nervous about bad things happening. Maybe not on the order of your gas tank "discharging" suddenly, but certainly the possibility of heating conductors enough to start a fire.
carbon nanothings (Score:3, Informative)
However, carbon nanostructures are perhaps the most promising areas of energy storage research. When someone finds out how to do with n
Re:What about all the advances? (Score:5, Insightful)
In the late 70's I was involved in the design of electric cars. We're all driving them now, right?
Throughout the 90's I was involved in the design and development of electric cars on a smaller scale (of the cars themselves. The work was actually more extensive).
End result was a complete lack of revolution.
I canna change the laws of physics Cap'n.
Over the years batteries have gotten a bit better due primarily to better manufacturing methods of existing technologies, not to any real breakthrough.
Some day we just might have to deal with the fact that batteries are WYSIWYG. I'd love to have a simple wind up toy that could fly me to China in an hour, but, as my mother used to say, wishing won't make it so and just because we wish for a "technology" ( applied science ) does not imply that such a technology ever will, or even can, exist.
KFG
Re:What about all the advances? (Score:5, Informative)
Most laptops use Li-Ion - a technology that brings the term "suck" to the title of this article. Li-Ion sucks. Not the other technologies out there. They aren't offfered.
NiMH is a decidedly better technology. Matsushita (who, BTW, is currently in arbitration with Ovonic Battery over a patent dispute) has brought the new Toyota Prius battery up to some astounding levels of power and energy density. And the batteries are proven to last for the vehicles lifetime - not this puny 500 cycles like Li-Ion that we get with laptop batteries. Didja ever wonder why your laptop's 2-year warranty didn't include the battery?
Because margins are already too thin. They can't afford real battery technology. We'll have true wireless only when the electronics downsize their power requirements.
Re:What about all the advances? (Score:3, Informative)
Actually, there is one place where battery technology has seen incredible advanced, and that is power tools. Ten years ago, a
Not my "Nondescript metal cylinders" (Score:4, Funny)
Why is he talking about Nukes? I mean, yeah, you never seem to get them (Top of the list, five years running! But do my parents see fit to get one? NEVER!), but what place do they have in an article about batteries?
Re:Not my "Nondescript metal cylinders" (Score:4, Funny)
I was sorely tempted to drop in a comment about your constitutional right to nukes but then realised that there is a right to bear arms (short sleeve shirts anyone?) but says nothing about batteries.
Re:Not my "Nondescript metal cylinders" (Score:4, Funny)
Uday? Is that you, Uday? ;)
-T
Fuel Cells... (Score:5, Interesting)
Its pretty cool, because you always hear about fuel cells, but almost never see a commercial application.
Hopefully once they make it smaller...
Time to dig out an old favorite quote (Score:5, Interesting)
I suppose that would be somewhat hazardous wouldn't it.
At least a current day leaking battery will leave a nasty burn mark on my table, not burn thru the table and into the concrete floor underneath.
I think the key is.. (Score:5, Interesting)
Now the downside to this avenue is that each battery would have a battery (likely internal). However this wouldn't have to be nearly as big-- by design, make a very low current required to start/stop the chemical process in the larger battery, which is now free to be much more caustic in nature. Now the battery may still explode from mal-use, then again a passive fuse element could also be added which makes sure the battery permanently becomes in it's inactive state.
I'm not saying we know how to do half of this, it's just one option we can persue. Another option is fundamentally chance the amount of electricity anything handheld uses. This would be happening right now, but every time we make something more efficient, we make it faster so that it's consumption is more or less equal (usually more).
Re:Time to dig out an old favorite quote (Score:5, Informative)
http://www.iranchamber.com/history/articles/par
Re:Time to dig out an old favorite quote (Score:4, Funny)
It's just like most things... it's like a monkey fucking a football.
There. Now we have over-analyzed an attempt at humor.
The Adult Industry (Score:3, Funny)
Re:The Adult Industry (Score:2)
I was watching the news (Score:2)
Re:I was watching the news (Score:3, Interesting)
Like these? [pcworld.com]
Re:I was watching the news (Score:5, Informative)
what I want to know is... (Score:2, Interesting)
Re:what I want to know is... (Score:2)
Re:what I want to know is... (Score:5, Informative)
Thump ThumP Thump (Score:3, Funny)
Re:Thump ThumP Thump (Score:2)
Hey, is that the energizer bunny or a new robotic whore?
Re:Thump ThumP Thump (Score:4, Funny)
Q: What happens when you put the batteries in the Energizer Bunny backwards?
A: He keeps coming... and coming... and coming...
You can't rewrite the laws of physics... (Score:4, Insightful)
Quit bitching or open-source the laws of physics.
Re:You can't rewrite the laws of physics... (Score:3, Funny)
Then why did you? (Score:5, Informative)
2) Since the original electricity is a trivial cost of batteries, the question is how much energy we can keep in the battery, not how much we use to get it there, so this is utterly irrelevant.
3) Vacuums apply to pressures, not energies. Have you seen the sun exploding lately because it's more energetic than the surrounding vacuum? (No, sorry, flares dont count.)
Real problem with batteries: inorganic chemistry hasn't made any huge progress lately.
Solution: capacitors. GM is planning to use them instead of car batteries in the relatively near future.
Re:Then why did you? (Score:3, Informative)
They have seriously cool stuff, and they sell small quantities (i.e., 1) so you can play around. Their ultracapacitors have 10x the power density and 0.1x the energy density of batteries, more or less, so except for specialized applications you're looking at a combination of the two, not one or the other, in an efficient system.
Re:Then why did you? (Score:3, Informative)
Re:You can't rewrite the laws of physics... (Score:3, Informative)
Re:You can't rewrite the laws of physics... (Score:3, Informative)
batteries smatteries (Score:5, Funny)
Re:batteries smatteries (Score:3, Insightful)
I'm sure battery vendors can find something to do more or less the same but why should they when they could continue charging you? Salesman: Ok I'm gonna give you this product and dont worry you will never have to see me again! Dream on. Its not in the vendors best interests to do something like that so don't expect anything to come out of their labs
Re:batteries smatteries (Score:4, Insightful)
Whatever will they think of next? Now excuse me while I put on my grandfather's watch, which is still ticking away after seventy five years, despite the fact that there is no way to wind it.
Re:Your LED flashlight must of been just crappy (Score:3, Interesting)
Radioactive decay batteries (Score:4, Interesting)
Such a small amount of material per battery would make it safe, but would last years... ( not forever, but with teh way things are designed these days, at least long enough for the device to fall apart...)
Re:Radioactive decay batteries (Score:3, Interesting)
there's one in almost every older pacemaker. there was somne research at MIT for using them in wearable computing.
Re:Radioactive decay batteries (Score:3, Funny)
If only (Score:5, Insightful)
Re:If only (Score:2)
Not enough to run a laptop, but certainly enough for a potato clock.
Movement power! (Score:3, Funny)
How about one of those blood sugar powered [smh.com.au] setups. Then your laptop could help you lose weight without all that inconvenient moving around. I can see it now. "I need to finish this paper by midnight, bring me more Krispy Kremes NOW!"
The greatest inventor in western history (Score:4, Informative)
the standard tradeoff (Score:4, Insightful)
Efficient programms fashionable again? (Score:2, Interesting)
Hmm... VERY dated ExtremeTech article! (Score:4, Funny)
The wonderful side of this dream is that some engineers expect it to be reality by the end of 2001"
Err... whats the hold up? Are they finishing duke nukem first?
Actually, they are a great gift! (Score:5, Funny)
Pack of batteries with label: Toy not included.
-Adam
What about toxicity? (Score:5, Interesting)
- One 10-Watt halogen light with a lead-acid battery. It's lasted me for several years, but is starting to loose it's charge.
- 2-3 blinking lights which take any old AA & AAA batteries.
I'm getting sick of having to toss the discharged alkaline batteries all the time, and am looking for a replacement.
Since I'm comparing the prices of the different kinds of batteries and chargers, I'd also like to compare the different toxicity levels.
Are NiMH's safer then NiCADs or Alkalines?
Ironically, my lead-acid battery gets the most frowns, but it seems like it's actually one of the least toxic options. There are several places near me which recycle lead-acid batteries (They strip the batteries, neutralize the acid, and take the lead; all in-house).
Re:What about toxicity? (Score:4, Interesting)
A good set of name brand batteries with an overnight charger will quickly pay for itself. The only problem with them is that they will run down on their own if you don't use them often, which is why I use alkalines for remote controls. So if you remember to swap the batteries every week or so, to make sure you have a fresh set in there you should be in good shape.
Whatever happened to those bike lights that would pull power from the rotating wheels? With the low current that LEDs require I would think such a system would work well.
Generator Hub (Score:3, Informative)
This one [sheldonbrown.com] is the Shimano NX-30, and it will power a 6 watt front headlight.
Maybe not as bright as your old 10-Watt, and sure, there is a little drag, but it's not bad, and you get to stop charging your bike lights for good. And $60 for the functionality of a battery *and* a front hub is a good deal.
spreer
Re:What about toxicity? (Score:3, Interesting)
A: They don't produce that much light, and they don't blink. I bike through rush hour traffic, and need bright lights like my 10-Watt halogen, and bright flashing lights, which get the drivers attention.
B: They increase the effort required to pedal, especially considering how dim the lights are.
C: The light output is directly connected to your pedalling effort: The light dims when
batteries (Score:2, Insightful)
How about more plugins? (Score:2, Interesting)
It seems simple, but even with recent inovations in other energy storage (fuel cell, etc), we won't see anything small (battery-wise) coming to market for some time. KISS (Keep It Simple Stupid)
Human battery! (Score:2)
I don't suppose... (Score:3, Insightful)
Why would battery manuf. make a better battery? (Score:2)
It's like asking why hookers are popular.
Sure, release a 'better' battery every couple of years, and sit on the pile of money. Better battery?
I can sooner see MS making Office for linux.
Lithium Ion batteries are great. (Score:2, Interesting)
Batteries are not the constriction... (Score:3, Insightful)
Imagine what you could do if your hard disk could read data as fast as your processor could handle it (think RAM-like or cache-like speed)
Actually, there IS a lot of R&D (Score:5, Informative)
For disposables, consider that we've gone from carbon-zinc to alkaline to lithium chemistries. In the case of Eveready, they have the L91 lithium AA, and it's pretty amazing in terms of power density and battery life (about 3X alkaline.) It's now about 10 years old.
Rechargables have gone from lead-acid to Nickel-Cadmium to Nickel Metal Hydride and also Lithium-Ion.
Keep in mind we're talking about a chemical device here that's storing larger and larger amounts of energy as times goes on. More energy = more potential for bad things to happen. Since it's chemical we're dealing with chemistry, materials science, and environmental factors (heat/cold, issues of outgassing, etc.) There's a lot more going on than a simple metal tube here.
A lot of the work that goes on is hidden -- it's hidden in the fact that the battery works for more than a few cycles. Many battery chemistries are very touchy when it comes to repeated cycling, for example, while others if not formulated (or charged) correctly would outgas or swell and explode. If any of you remember the good old days of carbon-zinc, it was routine to have things destroyed by leaking cells. That's one of the reasons the battery manufacturers actually offer warranties on the devices using them. (Think about that: It's like Exxon giving you a warranty on your engine if the gas harms it.)
While the future is probably fuel cells (I'd bet on methanol cells in particular, perhaps like Neah Power is working on) it'd be wrong to think that batteries aren't improving -- or that they won't be around for a long, long time.
no battery advances? huh? (Score:5, Insightful)
Today's batteries are unbelieveably nice and great compared to the utter crap we had to use just 7 years ago.. NiCad batteries would get a memory effect, last very short times and have abyssimal storage capacity.
batteries have came a long way, and they will continue to improve... how about making processors and displays that dont suck down amps of power?
the problem isn't the batteries, the problem is the horrible inefficency of today's tech!
Re:no battery advances? huh? (Score:5, Informative)
Actually, the "memory effect" thing is a myth. What really happens with multi-cell nicad packs is one or more of the cells runs down to 0 volts before the rest do and subsequently gets "anti-charged" by the other batteries in the pack. The reverse voltage damages that particular cell, reducing its capacity. A multi-cell pack only gives full voltage for as long as the weakest cell in the pack can. The weird thing about the "battery memory" thing is that the recommended means of avoiding problems (full discharge before recharging) is more likely to result in cell damage. Then again, the difference between that and the opposite (recharge frequently without discharging) is practically nil: nicads are just crap.
Fuels will be the new print cartridges (Score:5, Funny)
Battery lmitations (Score:3, Informative)
why would they get better? (Score:5, Insightful)
I guess on a side note, my rechargable batteries are a godsend. While you can debate the economics of it all (40$ for a charger and 4 batteries), I just like not having to worry about having batteries for my MP3 player [Nike PSA64]. I use it primarily for working out, I go through a battery every week or two, throw it in the charger, and then replace it. They've lasted all summer and still give me numerous days of life. Prior to purchasing them, I was going through batteries like a mad man, buying a pack every two weeks to keep up with my working out. I think its the best solution for anyone who goes through a lot of batteries...
The King is dead. Long live the King. (Score:5, Insightful)
The lack of headway is the chemistry, not the funding or effort. There's a finite limit on the amount of energy you can safely store and retrieve chemically from a given volume. A lot of development is focused on getting higher energy/volume ratios, lithium polymer and methanol fuel cells are good examples of this branch of development.
Looking for better battery chemistries is much more difficult. Between environmental concerns and ridiculous patents trying to market new chemistries isn't a cake walk for any company. There's a lot of materials that can be used in batteries. Not all of them are things you want ending up in land fills or in the hands of complete and utter morons.
Batteries suck for a reason (Score:5, Interesting)
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.
What I wanna see is... (Score:3, Insightful)
And like what was mentioned in another post, faster charge times. I would drive an electric vehicle everywhere if I could go 200 miles (with no slowing down towards the end) per charge, and a completely full charge only took 10 minutes.
Batteries *have* gotten better ... (Score:5, Interesting)
The non-rechargable batteries gotten much better, going from the Zinc cells to the modern alkalines -- the capacity has gone up greatly (a factor of 10 or so?) And then there's the non rechargable lithium cells that can hold MUCH more (and costs more too, of course.)
Also, and perhaps even more importantly, the rechargable cells have gotten much better recently. Maybe fifteen years ago, you'd buy 500 mAh AA NiCd cells ... now most people buy 1800 mAh NiMH cells, and for a few dollars more, you can get 2100 mAh AA NiMH cells.
(Quick aside, NiCd vs. NiMH: NiMH have more capacity, but usually cannot deliver as much current in a very short period. NiMH cells do not suffer from voltage depression (often mistakenly called `memory'). NiMH cells are not as environmentally unfreindly as NiCd. NiMH cells usually don't last quite as long as NiCd cells. But for the most part, for most applications, NiMH and NiCd cells can be used interchangably.)
And more recently, Li-Ion and Li-Poly cells have really come of age. These cells often have energy densities and power densities several times greater than what NiCd and NiMH cells have. Li-Ion cells were extremely fragile and could not handle abuse at all, but the new Li-Poly cells are overcoming many of these shortcomings.
Ten years, electric R/C planes were very rare. Now, thanks mostly due to the improvements in batteries, they're found all over the place, and they can perform just as well as the glow and gas powered planes in many cases. All three types of batteries (NiCd, NiMH and Li-Ion/Li-Poly) have improved greatly recently, and all three are quite popular with pilots today.
(Li-Poly especially looks incredibly promising for the future -- today, some planes with motors powered by them can often fly a full hour on a single charge, and things are getting better all the time.)
In short, I don't agree with Michael Rogers at all -- there's all kind of developments being made in batteries. It's just that they're not happening fast enough for him :)
(Semi-relevant aside: I have a TRS-80 Model 100 laptop computer. It's powered by 4 AA batteries, and it lasts a very long time. Perhaps the problem isn't the batteries -- maybe it's the laptop makers who use CPUs that use so much power!)
Batteries aren't the problem. (Score:5, Insightful)
Maybe the problem isn't the batteries, maybe the problem is what we expect them to do. Sure a laptop that runs Unreal Tournament 2003 at 100 fps is nice, but when was the last time you saw anyone playing it off their battery.
Portable eletronics will always need to be more rugged and less power hungry then their stationary brethern, without exception, no matter how good batteries get. So here is a bright idea.(let me know if this gets too deep for you) How about we stop expecting portable electronics to be as powerful as non-portable electronics?
Sure try to make better batteries, work as hard as you can at it, but keep in mind what Lone Star said to the Druish Princess Vespa: "Take only what you need to survive"
No, and by that I mean zero, laptops need a DVD-R. Almost no laptops need any 3D accelerator. Why, on god's green earth, do cell phones need a camera? Why does a PDA need enough hardware to play videogames? Do you buy a cellphone for a camera? Did you go shopping for a portable video game system and say to yourself, "Hey this GBA is pretty cheap and has really good games, but I am looking for something that is 4 times as much and is hard as hell to play games on?"
Opmization is what must prevail. Making one machine that does everything, will not work. Give the people what they need. No one is buying a phone for its camera. They buy a camera for that. Power saved. No one needs to burn a DVD while flying from New York to LA. Power saved.
I mean look at the Game Boy. The first took 4 AAs and lasted 4-6 hours. The Game Boy Color took 2 AAs and lasted 10 hours. The Game Boy Advance takes 2 AA and lasts 15 hours. Batteries have not gotten that much better, but today's Game Boy users are spending 1/8th as much on them.
Programmers need to care about memory and processor usage again; engineers need to care about power consumption again. Do you really think that an mp3 player really needs to take 20MB of space? Power saved.
Batteries aren't the problem. People are.
SW
Re:Batteries aren't the problem. (Score:3, Informative)
OK, even if I agreed that all of those things are not necessary in portable electronics, there's one thing that's totally critical in portable electronics and also a huge power drain: wireless communications. Trust me, it's not the camera in the cell phone that's wasting your battery, it's the transmitting.
The "k
Of course there's been limited/no development (Score:3, Insightful)
Batteries, Light Bulbs are two of the oldest members. Neither set of manufacturers have any kind of incentive to make their products last SIGNIFICANTLY longer. Their revenue streams are BASED on the fact that you have to replace them.
The faster you go through them, the cheaper they are.. (carbon batteries are cheap compared to Alkaline, which are cheap compared to NiMH), becase they can make up the different in volume. But they still have to make money.
So, what incentive do they have to make a battery that lasts substantially longer? I shy away from replacing my laptop batteries until the absolute last moment, because they run about $120 each, and most people that have one will tell you that a used laptop battery (charge/discharge, lather rinse repeat) will only last about a year, maybe 2 before your runtime is in fractions of an hour..
It's simple economics.
The article repeated some misconceptions... (Score:5, Informative)
Battery chargers today are much more sensitive to the charge state of a battery and as a result they're much less likely to overcharge a battery.
According to the GE manual on NiCd batteries, there really is a "memory effect" on NiCd batteries, but it relates to their use on board spacecraft in orbit where charge and discharge cycles are very regular. This effect is slightly different from that which results from overcharging the pack. Most people don't charge and discharge their battery packs so regularly.
In the case of the batteries in orbit, the full capacity can be restored by one or two irregular charge/discharge cycles. However in the case where you overcharge the batteries, you actually lose capacity in the battery.
By the way, overcharging a NiCd battery is less damaging than overcharing a NiMH battery. The former can recover some of it's capacity by exposure to air to recover the hydrogen and oxygen gasses it released, but the latter generally doesn't.
Suck ? I thought they were beginning to BLOW (Score:3, Informative)
I've seen reports lately of batteries blowing up.
Nokia: Other Batteries Explode [unstrung.com]
Google [google.com]
While you make a good point that battery technology has failed to make the leaps that other technologies (like disk drive technology, for example) have, the issue remains, increasing energy density may cause explosions (batteries blow - literally), other technologies in comparison don't have similar failure modes (few, if any, disk drives cause serious injuries).
Re:Summarizing (Score:2)
Re:Summarizing (Score:2)
I don't make the rules, I just regurgitate them from my years writing for the school newspaper.
Re:I wonder if... (Score:5, Funny)
Re:I wonder if... (Score:2)
Well, tehnically in practice, you sell batteries based on perception of length of life. Most people don't go to Consumer Reports to know what battery to buy.
Helpful Hint: always own like 2 more rechargable batteries than you intend to be using at any given time. Keep these charged and near the charger. WHen yoour rechargable using gadget runs outta juice, swap.
Re:I wonder if... (Score:5, Interesting)
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.
Re:I wonder if... (Score:5, Interesting)
The instructors was somewhat insane, but what he said makes sense. He's also a considered a leading authority on Extra-Terrestrials. For as insane as he was, they classified a bunch of basic research he did into application of nuclear physics. You also couldn't find a problem in the book he couldn't solve. He was really smart about his physics, and it's applications. He taught all of the electronics classes.
It's also backed up by my emperical evidence of picking up the light bulbs that are 130v instead of 120v last longer in fixtures over the last 5 or 6 years. They aren't any more expensive then the bulbs you pick up a Walmart.
Kirby
Actually... (Score:3, Informative)
When you switch one on, the tungsten filament is still cold, and - like most metals - the resistance of the filament is lower at lower temperatures.
This is what causes a major surge in amperage, and this is what actually 'breaks' the filament. The cold period lasts only a split second, but this is enough to fry a weak spot in the filament.
The weak spots are formed during 'normal' use, since it is virtually impossible to create a wire with even
Re:I wonder if... (Score:3, Interesting)
btw, there IS longer lasting light bulbs that almost never burn out. i can't remember the reason why they are longer lasting though
Re:I wonder if... (Score:3, Informative)
I've got a minor in physics, I understand the basics of electricity.
When was the last time you actually saw a bulb blow while it was running? I've never seen it happen in all might life on an incandesent light bulb. Ever. It is something a
Re:I wonder if... (Score:2, Insightful)
-Hil
Re:I wonder if... (Score:2)
It's simply a lack of advancment in research.
Laptops, MP3 players, and most other such devices use Lithium Ion batteries, which are sorely due for a replacement. Most people's complaints are not that they don't last long (The batteries in this Dell are rated for 500 discharge/charge cycles each) as much as they are heavy and don't hold enough of a charge. This machine, for example, can't be on for more than 4 hours (or something like 8 with the screen off) if both of the bays have batteries in the
Re:three words: (Score:2)
Re:three words: (Score:5, Informative)
Re:three words: (Score:4, Insightful)
I'm sorry, but cheap alkalines are a good solution if you have a flashlight that you hardly ever use but that's about all they're good for. It does nothing for the case of the laptop or PDA, and they're envinronmentally unfriendly for anything that is used a lot or has a high draw.
Re:What do the submarines use? (Score:5, Informative)
Having just attended a Canadian Forces Naval briefing on this very topic, I'm glad you asked :).
Naval subs use massive "wet" batteries, something akin to what your car uses, except exceptionally massive, typically filling two large-ish rooms. They are exceptionally heavy.
Note that diesel-electric submarines are only rated to run for aat most two weeks between charges. They have to surface to run their diesel engines in order to recharge their batteries, as the diesel engines need clean air for the combustion, and need to be able to vent their exhaust gasses.
This is a disadvantage over nuclear submarines, which can stay down for months at a time. The benifit of them, however, is that diesel-electric subs are quite a bit more silent than their nuclear counterparts :).
Yaz.
Re:What do the submarines use? (Score:4, Informative)
Note that you can also charge such subs while in dock, by running cabling to a charge port (no kidding!).
Obviously, you need to pick and choose what types of missions you use such subs for. As I mentioned, they aren't for long-duration underwater missions. They serve a different purpose than nuclear subs serve.
And BTW, the Canadian Forces routinely detects the US Los Angles-class nuclear subs while they're supposedly running in "quiet" mode :).
Yaz.
Re:What do the submarines use? (Score:4, Interesting)
I just saw one of the Los Angeles class subs. They are indeed impressive machines.
I'm not trying to slight the US's nuclear subs. They're obviously not rusty old junk buckets making a racket that any old fishing trawler can pick-up. They're exceedingly advanced machines.
However, if you run a decibel test between a Los Angeles class sub and one of the Canadian Forces Victoria class diesel electric subs, the Victoria class scores better. They have their own issues, of course (the Victoria class subs needing a whole lot of work to make them seaworthy for one thing :P)
Yaz.
I know this one (Score:3, Informative)
You can't just turn off (and turn back on!) a nuclear reactor the way you can turn on or off a fossil fuel engine (whether diesel or anything else). It's a major, time consuming process. So, shutting off the reactor to "run silent" is not an option.
Yes, reactors are noisy relative to batteries. They have hot fluids being pumped around in heat exchangers and driving generating turbines.
Re:Super Capacitors? (Score:4, Informative)
Nonsense.
1 Farad = 1 Amp at 1 Volt for 1 Second
As anyone who knows capacitors can tell you, a farad is a huge unit. To put things in perspective, common, everyday capacitors often have capacitances measured in picofarads (a picofarad is one-thousandth of one-billionth of a farad).
Now, how much capacitance would it take to equal a single AA battery?
A typical AA battery might be rated at 2200mAH at 1.5V. It doesn't actually keep that voltage up the entire time, but let's just pretend that it does.
2200mAH = 2.2AH = 7920As
So, a typical AA battery delivers 7,920 amp-seconds at 1.5V. An equivalent capacitor would need to have a capacitance of around 11,880 farads. That's to equal ONE AA battery. No such capacitor exists, and even if one did, it would be absurdly dangerous to handle.
The strength of a capacitor is its ability to deliver its power very, very quickly. That's why a big capacitor would be so dangerous -- imagine discharging all of the power in a AA battery in a ten-thousand of a second. The strength of a battery, on the other hand, is its ability to deliver (relatively) unbelievable amounts of power, but it can only do so over much longer periods of time.