A discussion of battery technology

[bobsmith1492]

It seems to me that improved battery technologies are essential to continuing the way of life the Western world has grown accustomed to. With the proliferation of portable electronics, exponential increases in gasoline consumption (global scale, think China and India), it would seem electric vehicles will become profitable and desirable - given the proper battery technology.

I found an excellent article comparing current, developed technologies:
http://www.buchmann.ca/Article4-Page1.asp

Essentially Lithium Ion and its derivatives are leading in the most crucial aspect for an electric vehicle: energy capacity per unit weight. However, they are also the most expensive and still slightly dangerous, though nothing to be overly concerned about.

What else is out there?

Capacitors/supercapacitors: I read an article at AT/DT about promising developments in capacitors approaching battery-like levels: http://www.dailytech.com/MIT+R...citors/article3043.htm
(sorry, long link...)
Advantages: quick recharge, long lifetime
Disadvantages: not available, extremely poor energy density

Essentially they are an interesting concept but need work... lots of work.

Fuel cells: They appeared a few years ago and generated some hype which quickly died. As far as I can remember they were extremely expensive, requiring precious metals, and ran on hydrogen. Basically they could be considered a hydrogen battery, where charging consists of generating hydrogen to resupply.
Advantages: higher energy densities (someone correct me if I'm wrong)
Disadvantages: price, lifespan (not necessarily), availability and (maybe) safety of hydrogen

It would seem fuel cells were just a blip on the radar and may remain as such unless new breakthroughs are made. Distribution of hydrogen will always be an issue - electricity for battery charging is widely available, though infrastructure upgrades will be needed in any case for the country (talking US but any country should apply) to switch to electric vehicles on a large scale.

Thermal batteries: These are chemical cells that mix two substances (sodium or lithium and sulfur, for instance) that literally burn, at high temperatures, for a certain amount of time producing massive amounts of electricity.
Advantages: excellent energy density, cheap materials, no internal discharge during storage
Disadvantages: as of now they are not rechargeable and extremely dangerous. At work there was a system we worked on that was a backup hydraulic pump for jet fighters that ran on a thermal battery. They said sometimes the battery would spew jets of flame ten feet out the side when they ran out.

If they could be better controlled, trusted in the hands of dumb consumers with hammers and car accidents and lawyers, and refueled, they might have a future?

Ok, that's what I've got so far. Basically we still need a breakthrough in electricity storage, or at least that's the vibe I'm getting. That said, I'd like a GM Volt some day providing they figure out what battery to use.

 

[Nathelion]

The problem is twofold though. Even if you make a good ultraportable battery, where are you going to get the actual electricity from? That's right, coal and oil...

 

[BrownTown]

Originally posted by: Nathelion
The problem is twofold though. Even if you make a good ultraportable battery, where are you going to get the actual electricity from? That's right, coal and oil...

Well first off essentially 0% of electricity comes from oil, the only place oil is used these days is in emergency generators that only run when the load is so high that every other resource is being used, and all new generators for this application are natural gas anyways, so oil is going down not up. As for coal, currently there are 200 years worth of coal in the USA whereas oil has peaked this decade, so where oil production will continue to go down over the rest of history there are still many decades before the same can be said for coal and therefore there is actually room to add additional capacity for coal as opposed to oil. Also coal is 1/4th the cost of oil per BTU, so the cost factor favors coal heavily over oil if batteries were developed. Also, there is nothing saying coal would have to be the only source, natural gas still has some more room to expand, nuclear fission has a good deal more room to expand. Wind also can expand considerably. So basically where oil is a commodity whose production has no where to go but down resources like coal, natural gas, nuclear, and wind have room to expand. Since these technologies currently cannot power cars the obvious idea is to use electric motors and batteries so as to compensate for the end of "cheap" oil in the near future.

There are other ideas of course, converting coal to liquids is one idea, converting tar sands to oil is another, but these are exceedingly energy intensive and not all that efficient, whereas an electric car (if perfected) would be a much simpler alternative. Also for the environmentally conscience people there is the fact that tar sands and coal to liquids are exceedingly destructive to the environment. Not to mention that if you are one of the global warming people considerably more CO2 would be released by these methods over electric cars (assuming that the electric mix stays similar to its current usages).

 

[Cogman]

I think that currently the most promising tech is Li-Ion. It's tried and true and making great strides towards speed of recharge rate and energy density. The most promising developments IMO are the movements to the nanoscale of manufacturing. Once we get there (may be 10 years or less) we should have some really good energy density and storage capacity, heck, even super capacitors should be looking more feasible by that time.

As far as the electric car goes, I think there are 2 things that are killing it, cost and Public opinion. For the cost, electric cars are almost always more expensive (initially) to buy then a regular car. People don't like that and usually won't jump for it. Next is public opinion. I can't tell you the number of average joe's I have spoken to that say they would never buy an electric car because "There engines aren't very powerful, and they aren't very fast" A myth propagated by the fact that most electric cars are targeted at high MPG and eco-friendliness. Heck, even the eco-friendliness campaign is a detouring fact for a fair portion of the target market (the more wealthy)

I think that the ability to do a good electric car exists today, but it probably won't fly for a couple of years. People don't like change and a system to power the cars just wont be implemented until it has to be.

 

[Modelworks]

I think things like converting aluminum to hydrogen are the way to go.
The aluminum pellets are easy to transport and safe.
You would just drop the pellets in your tank with a measured amount of water.
Hydrogen bubbles off, straight into the fuel line.


http://www.autobloggreen.com/2...ling-hydrogen-economy/

Woodall says that the reaction of aluminum with water has the same energy content per unit weight of oil, about 20,000 BTUs or about 6 kWh per pound. And, since aluminum is safe and plentiful, it has high potential to create "aluminum enabling hydrogen economy"

If you can catch it , watch the series Eco-tech that is running now on the science channel.
http://science.discovery.com/t...id=48.x.122449.34341.x

It had tons of new energy systems that I had not previously heard about.

 

[Throckmorton]

Didn't you guys hear about the brand new battery technology with 10x the capacity?

 

[silverpig]

Originally posted by: Throckmorton
Didn't you guys hear about the brand new battery technology with 10x the capacity?

The silicon nanowires enhancement of lithium ion batteries? Yup

 

[jagec]

Originally posted by: bobsmith1492
Fuel cells: They appeared a few years ago and generated some hype but quickly died. As far as I can remember they were extremely expensive, requiring precious metals, and ran on hydrogen. Basically they could be considered a hydrogen battery, where charging consists of generating hydrogen to resupply.
Advantages: higher energy densities (someone correct me if I'm wrong)
Disadvantages: price, lifespan, availability and safety of hydrogen

In the media, yes, they appeared not too long ago and interest faded shortly thereafter. However, they've been available for decades, NASA uses them a lot, and active research is still being carried out on them. I was part of a research group myself as an undergrad. There are methane fuel cells as well, and it's possible to supply them with hydrogen using the water-gas shift reaction, so they aren't restricted to a "hydrogen battery" mode of use.

The prime disadvantage right now is that they are very expensive (proton exchange membranes, platinum catalyst), and their efficiencies aren't really great. Theoretically they could do better than the ICE, since they are not limited by the Carnot cycle, but in practice we at least were unable to reach this mark. Mind you, this is undergrad research.

As for lifespan, I don't know what you mean by this. You can run a LOT more hydrogen through a fuel cell before it craps out on you than you can charge-cycle most batteries. Indeed, I'm not really sure what the breakdown mechanism would be, although I'm sure eventually something does fail.

IMHO the safety aspect of hydrogen isn't as big an issue as people make it out to be. Gasoline is pretty horribly unsafe, and yet we're able to let Joe Moron drive around in a car jammed full of the stuff without having much trouble.

I don't think fuel cells are "the answer", but I just figured I'd put in my piece.

 

[PolymerTim]

I'm with jagec on this one. Fuel cells in one form or another have been around for a long time. And there is more research going on with them now than ever before. I don't work with them myself, but several students in my research group and department do. There are many different kinds of fuel cells (just check out wikipedia) with a wide variety of uses. Our work is on proton exchange membranes, but I also no someone in industry working on a molten carbonate version (more useful for industrial generators than portables).

Here's another link with a decent summary of fuel cells and current progress. The main research in my group is on making a membrane that has mechanical integrity with high proton conductivity at higher temperatures and lower humidity. Someone asked about how fuel cells fail. At least for PEM fuel cells, the main causes are catalyst poisoning (carbon monoxide in the fuel reacts with the platinum catalyst and kills it) and mechanical failure of the polymeric membrane (you've basically got a water swellable plastic sitting at 80 deg C in the middle of a caustic electrochemical reaction).

Increasing the operating temperature will reduce the amount of catalyst poisoning, but most films won't tolerate the increased temperatures in part because the humidity tends to go down and the film dries out. Nafion has been the gold standard for quite some time, but it is very expensive and does not have the required properties for the next generation fuel cell. The race is on and this is one of the hot areas in polymer research today. It should be interesting to see where it gets us in the next few years.

 

[jagec]

Originally posted by: PolymerTim
Someone asked about how fuel cells fail. At least for PEM fuel cells, the main causes are catalyst poisoning (carbon monoxide in the fuel reacts with the platinum catalyst and kills it) and mechanical failure of the polymeric membrane (you've basically got a water swellable plastic sitting at 80 deg C in the middle of a caustic electrochemical reaction).

Increasing the operating temperature will reduce the amount of catalyst poisoning, but most films won't tolerate the increased temperatures in part because the humidity tends to go down and the film dries out. Nafion has been the gold standard for quite some time, but it is very expensive and does not have the required properties for the next generation fuel cell. The race is on and this is one of the hot areas in polymer research today. It should be interesting to see where it gets us in the next few years.

Yeah, we were using Nafion, but in the quarter when I was working with that group, we never got around to assembling the cell. I was preparing the membranes, the other people were working on a patterned catalyst printing technique, and it kind of felt like a group in transition. They had a test stand, and apparently had been trying a few different ideas, but we simply didn't get around to it.

I don't remember how they dealt with the hydration issue...IIRC the hydrogen side tends to dry out, and the oxygen side tends to flood. However, if you just use air and keep pumping it through, you can get pretty good control of humidity on that side. You have to somehow humidify the hydrogen stream, though. Since we were using a nice little laboratory setup with a hydrogen bottle, catalyst poisoning really wasn't an issue.

 

[bobsmith1492]

Originally posted by: silverpig

Originally posted by: Throckmorton
Didn't you guys hear about the brand new battery technology with 10x the capacity?

The silicon nanowires enhancement of lithium ion batteries? Yup

The problem is, as always with said nanotechnology: how does one mass-produce it inexpensively?

Regarding fuel cells, then, it would seem there is still work to be done to produce a viable product, correct? Building one for a billion-dollar satellite or the Space Shuttle is a somewhat different prospect than building millions of smaller ones to be abused by consumers. Still they have good lifespan - but what about this catalyst poisoning? Is that not really an issue or just in the super-long-term, i.e. longer than LION batteries would last?

 

[PolymerTim]

You pretty much hit it on the head. Working fuel cells have been around for a long time since NASA doesn't care how much they cost, and the fact that a byproduct of the reaction is potable water is a nice bonus.

Functioning fuel cells have been around for a while now, but are not mainstream for the very reasons you suggest. The lifetimes and product costs do not allow them to be cost effective. It's kind of like these new SSD drives - we've had the technology around for them for a long time, but they were way too expensive. Now, for only a few thousand dollars, you too can have your own! I believe the time will come when a fuel cell is running your laptop, but I think it is going to take a few more years at least before it is commercially viable.

I think the catalyst poisoning primarily comes from the fuel source. Thus, lab researchers have the luxury of working with high purity hydrogen gas when testing out new fuel cells, but in the real world, there is always going to be some percentage of CO in a reasonably priced fuel like methanol or ethanol and its effects will slowly build up in the catalyst reducing its efficiency. How long it lasts will depend not only on the purity of the fuel source, but also the operating conditions inside the cell (which is one reason why higher operating temperatures are desired).

Keep in mind that most technology starts off very expensive and gets cheaper as it is developed. There are countless inventions that would never have succeeded financially if they weren't first backed by the government. Nanotechnology isn't innately too expensive, we just have to learn how to use it properly. In research, we often use expensive, brute force techniques to prove concepts and see how things work. Then, over time, a few of the more promising results get refined until they are commercially viable. A good example of this is carbon nano-tubes. Once thought to be expensive toys of research labs (think $1000 per gram) they have recently started to be produced on industrial scales.
Nanotubes - coming to a product near you (in the next decade).

-Tim

 

[thebeyonder]

the future of battery technology is in room temperature superconducting materials.

they will probably be some kind of ceramic structure, doped with yttrium and/or gallenium.

such a material will be able to hold a charge much longer than any modern battery, maybe even practically forever. just as importantly, it shold be capable of practically infinite charge/recharge cycles. only problem I can think of is what the charge density might be.

that would revolutionize everything we do beyond belief.

you could get your home power supplies when you take a milk-jug-size block to the grocery store and have it recharged once a month. or once a year.

cars would run off electric motors with completely acceptably small batteries, oil would no longer be used as a fuel, only lubrication, and so we wouldn't run out of that for a long time.

battery powered consumer electronics would proliferate like bunnies on viagra. now they would be powerful, long lasting, and no problem at all recharging them. how about a watch battery that would last for 100 years, cost 3 bucks? a 1000 watt boom box you can take with you on the bus? heated clothes?

superconducting batteries is the answer.

 

[bobsmith1492]

Is there such a thing as superconducting batteries? Is the general idea to get current flowing in a loop and, since there's no resistance, it just won't stop and it can be tapped as necessary? I would think there would still be charge decay through stray magnetic flux and whatnot, ruling out the 100-year watch battery at the least and maybe making the whole concept a no-go. Plus we need to actually come up with a room-temp superconductor first... or, include a LN2 cooling system? That could be feasible I suppose.

 

[pm]

The more immediate next generation battery choice for electric vehicles is almost certainly LiFePO4 (lithium iron phosphate). They only have a slightly better energy density compared to NiMH, but are safer (no hydrogen venting), are capable of much higher charge and discharge currents (you could theoretically pull 1000 amps from a 10Ah cell), last longer (10+ years and their characteristics improve with age), and are more tolerant of temperature ranges.

The leading contender for US car manufacturers is A123 Systems: http://www.a123systems.com/

It has long been rumored that A123 will be the supplier to the Chevy Volt: http://www.chevrolet.com/electriccar/

Another website that I have liked a lot with battery information, is batteryuniversity.com: http://www.batteryuniversity.com/

 

[bobsmith1492]

I have read a lot at the battery university site already; good stuff.

Regarding LiFePO4 batteries, this was the only site I found that had any relevant info: http://www.iloveebikes.com/batteries.html
It still wasn't much, though. They sound great except for the lower energy density than standard cobalt LION batteries which seems like a step backward. Of course, if you need to effectively armor cobalt LION batteries to prevent punctures, then maybe the overall energy density would still be comparable. Then again, they don't seem to be in full production, either, as near as I can tell; a couple places offer them online but they don't look like reputable sites. Oh well; I still want to buy a Volt one day.

 

[PolymerTim]

Originally posted by: thebeyonder
the future of battery technology is in room temperature superconducting materials.

they will probably be some kind of ceramic structure, doped with yttrium and/or gallenium.

such a material will be able to hold a charge much longer than any modern battery, maybe even practically forever. just as importantly, it shold be capable of practically infinite charge/recharge cycles. only problem I can think of is what the charge density might be.

that would revolutionize everything we do beyond belief.

you could get your home power supplies when you take a milk-jug-size block to the grocery store and have it recharged once a month. or once a year.

cars would run off electric motors with completely acceptably small batteries, oil would no longer be used as a fuel, only lubrication, and so we wouldn't run out of that for a long time.

battery powered consumer electronics would proliferate like bunnies on viagra. now they would be powerful, long lasting, and no problem at all recharging them. how about a watch battery that would last for 100 years, cost 3 bucks? a 1000 watt boom box you can take with you on the bus? heated clothes?

superconducting batteries is the answer.

I have some problems with your logic here. You basically offer two claims: that these types of batteries 1) hold charge nearly forever; 2) have near infinite charge/recharge cycles. Even if we take these statements as true, most of your grandiose claims are premised on the assumption of extremely high energy density, which you claim yourself not to know (I bolded that part).

 

[pm]

Originally posted by: bobsmith1492
Regarding LiFePO4 batteries, this was the only site I found that had any relevant info: http://www.iloveebikes.com/batteries.html
It still wasn't much, though. They sound great except for the lower energy density than standard cobalt LION batteries which seems like a step backward. Of course, if you need to effectively armor cobalt LION batteries to prevent punctures, then maybe the overall energy density would still be comparable. Then again, they don't seem to be in full production, either, as near as I can tell; a couple places offer them online but they don't look like reputable sites. Oh well; I still want to buy a Volt one day.

I thought this discussion was purely abstract, but it sounds like you have a project in mind if you are searching for pricing...?


You can get them in small volumes (at relatively high prices) from radio control model online stores, like:
http://www.a123racing.com/
http://aircraft-world.com/shopexd.asp?id=5041


The cheapest way is to buy Dewalt 36V packs on Ebay and disassemble them, like described here:
http://www.slkelectronics.com/DeWalt/packs.htm

You can get 3.6V, 2.3Ah cells for about $10 each ($100 on Ebay for a dewalt 36V pack with 10 inside).

But if you want larger packs, they are either expensive or hard to find.

There's a lot of RC data in this thread, including a lot of testing. The RC guys love them because you can pull 50-100 times the capacity out of the cell without anything exploding, plus they are durabl, long-lasting and lack the dangers associated with lipoly packs
http://www.rcgroups.com/forums/showpost.php?p=6769001

And of course, Wikipedia:
http://en.wikipedia.org/wiki/Lifepo4

 

[thebeyonder]

Originally posted by: PolymerTim
I have some problems with your logic here. You basically offer two claims: that these types of batteries 1) hold charge nearly forever; 2) have near infinite charge/recharge cycles. Even if we take these statements as true, most of your grandiose claims are premised on the assumption of extremely high energy density, which you claim yourself not to know (I bolded that part).

yep. ideally, a superconducting battery would have those qualities. the first ones to hit the market won't be that good, and it would be a while before they approach the "ideal", but eventually they will come close.

that stuff I was saying about what it would be like and what they may be capable of, isn't farfetched even for a nonideal superconducting battery with whatever limitations it would have... wouldn't you agree?

 

[bobsmith1492]

Originally posted by: pm

Originally posted by: bobsmith1492
Regarding LiFePO4 batteries, this was the only site I found that had any relevant info: http://www.iloveebikes.com/batteries.html
It still wasn't much, though. They sound great except for the lower energy density than standard cobalt LION batteries which seems like a step backward. Of course, if you need to effectively armor cobalt LION batteries to prevent punctures, then maybe the overall energy density would still be comparable. Then again, they don't seem to be in full production, either, as near as I can tell; a couple places offer them online but they don't look like reputable sites. Oh well; I still want to buy a Volt one day.

I thought this discussion was purely abstract, but it sounds like you have a project in mind if you are searching for pricing...?


You can get them in small volumes (at relatively high prices) from radio control model online stores, like:
http://www.a123racing.com/
http://aircraft-world.com/shopexd.asp?id=5041


The cheapest way is to buy Dewalt 36V packs on Ebay and disassemble them, like described here:
http://www.slkelectronics.com/DeWalt/packs.htm

You can get 3.6V, 2.3Ah cells for about $10 each ($100 on Ebay for a dewalt 36V pack with 10 inside).

But if you want larger packs, they are either expensive or hard to find.

There's a lot of RC data in this thread, including a lot of testing. The RC guys love them because you can pull 50-100 times the capacity out of the cell without anything exploding, plus they are durabl, long-lasting and lack the dangers associated with lipoly packs
http://www.rcgroups.com/forums/showpost.php?p=6769001

And of course, Wikipedia:
http://en.wikipedia.org/wiki/Lifepo4

Oh, no, no projects for me; this is indeed abstract but I'm a practical kind of guy by nature and I want to see battery technology advance. It seems to me that a breakthrough in electricity storage would revolutionize the modern world as we know it and I'm trying to keep my eyes open and see where it may strike.

P.S. I have a friend who was big into RC racing up until a year or two ago; everyone was still using NiCads for their super-low internal series resistance and great pulse current capabilities. Are these LiFePO4 cells taking over from NiCads? Is that because they have higher power density than NiCads?

 

[bobsmith1492]

Originally posted by: thebeyonder

Originally posted by: PolymerTim
I have some problems with your logic here. You basically offer two claims: that these types of batteries 1) hold charge nearly forever; 2) have near infinite charge/recharge cycles. Even if we take these statements as true, most of your grandiose claims are premised on the assumption of extremely high energy density, which you claim yourself not to know (I bolded that part).

yep. ideally, a superconducting battery would have those qualities. the first ones to hit the market won't be that good, and it would be a while before they approach the "ideal", but eventually they will come close.

that stuff I was saying about what it would be like and what they may be capable of, isn't farfetched even for a nonideal superconducting battery with whatever limitations it would have... wouldn't you agree?

I doubt an infinite current loop is feasible to store energy. Googling came up with this article which somehow I can't access but apparently discusses only the effects of magnetic fields on "animals (including man)" and was published in 1989. There was another article apparently modeling via Matlab a superconducting storage system, published in 1996.

This patent describes a method of storing and retrieving power from a superconducting storage element but it appears to act more as an inductor or inductive coupling device than anything like a battery (BTW is there any good way to view the documents at that site? I have to yank them using a Mozilla plugin as opposed to viewing them via Quicktime online...)

Upon further reading, I found these interesting posts about some other superconducting application. However, they mentioned an interesting thing: "Bechtel has done
detailed design studies of a 10 GWh SMES coil." I have a friend at Bechtel, though likely in the wrong department, and I had thought about working there. Too late now, but interesting nonetheless. I suppose such a device may be possible, then.

In that case, I would imagine the intense magnetic fields and forces associated with the coil would be a major issue.
1. Stray magnetic flux would heat nearby metal (likely destroying it in the process) and waste the stored energy.
2. The intense forces asserted on the coil itself would probably be the limiting factor for the power density (I'd like to see the size of a 10GWH coil!!!) along with the current density limit for the material.
3. What happens if this device were onboard a car, the car hit a wall, and the (presumably ceramic) storage loop loaded with magnetic energy shattered into a thousand pieces? I'm imagining an inductor loaded with charge being disconnected resulting in thousands of volts across the terminals as the charge is dissipated. Magnify that by dozens of orders of magnitude and the result would be... what? A veritable EMP pulse? Instant ball lightning? It doesn't sound pleasant at any rate.

Does anyone have any more informed thoughts about this?

 

[thebeyonder]

the "superconducting batteries" on the drawing board don't use any kind of magnetic field to store charge, as with the inductance coil you mentioned. simply storage of electrons, as with conventional batteries (mentioned above), but instead using superconducting materials. so far it's looking like it may be some kind of doped ceramic.

on the scale of vehicles and large machines it sure does sound dangerous, because just liek you said, if there was an accident all that charge has to go somewhere and something's going to get messed up beyond belief! but the benefits would outweigh the dangers I'm sure.

 

[bobsmith1492]

Originally posted by: thebeyonder
the "superconducting batteries" on the drawing board don't use any kind of magnetic field to store charge, as with the inductance coil you mentioned. simply storage of electrons, as with conventional batteries (mentioned above), but instead using superconducting materials. so far it's looking like it may be some kind of doped ceramic.

on the scale of vehicles and large machines it sure does sound dangerous, because just liek you said, if there was an accident all that charge has to go somewhere and something's going to get messed up beyond belief! but the benefits would outweigh the dangers I'm sure.

I don't get it; what is the benefit of a superconductor in a traditional battery other than to reduce internal series resistance which is mostly a matter of the anode and cathode materials anyway?

 

[PolymerTim]

Originally posted by: thebeyonder
the "superconducting batteries" on the drawing board don't use any kind of magnetic field to store charge, as with the inductance coil you mentioned. simply storage of electrons, as with conventional batteries (mentioned above), but instead using superconducting materials. so far it's looking like it may be some kind of doped ceramic.

on the scale of vehicles and large machines it sure does sound dangerous, because just liek you said, if there was an accident all that charge has to go somewhere and something's going to get messed up beyond belief! but the benefits would outweigh the dangers I'm sure.

OK, maybe I'm missing something here, but I still don't get it. My original point was that it doesn't matter if your room temperature superconductor has perfect efficiency if it has a low storage density. The whole point of my previous response was that nearly all your applicable claims rely on extremely high storage density which you admit you don't know for this particular application. Your response did not address this problem at all.

Also, I'm no expert on electromagnetism, but bobsmith is right. It's not that you would use magnetic fields to store the energy as that your electrons flowing through a superconducting coil would create the magnetic field. In fact this is exploited in an instrument for a technique I use called nuclear magnetic resonance. The coiled superconductor is used to create powerful magnetic fields within the core. Granted, nowadays there is shielding so very little of it escapes the instrument, but it has to be dealt with. Conventional batteries do not have this problem as you seem to suggest since they convert this electric potential into chemical potential for storage.

I'm not trying to say that a room temperature superconductor won't be made, but I do wonder if it would be useful as a battery. On another note, I also found an interesting book linked off of wikipedia. If you skip to the last chapter, he gives some very interesting possibilities for future room temperature superconductors.
http://xxx.lanl.gov/ftp/cond-m...apers/0606/0606187.pdf

 

[Eeezee]

Originally posted by: Nathelion
The problem is twofold though. Even if you make a good ultraportable battery, where are you going to get the actual electricity from? That's right, coal and oil...

Solar and fission...

Yes, coal will be a big source of our power for another 50 years probably, but we could so easily build fission plants.

And the entire southwestern US is a prime locale for solar power generation. The good thing about the warmer climate is very few people use heaters in the winter - in the city, it's plenty warm at night. In the southwest, electricity consumption peaks during the afternoon, right when solar power generation peaks, thus reducing the need for tons of nightly storage. Why do so many people have a problem understanding this? Arizona and California have millions of homes, and they consume the most electricity when solar collectors would be generating maximum electricity! IT'S PERFECT!