MIT Develops Fast Charging Liquid Flow Batteries 135
An anonymous reader sends this from the MIT News office:
"A radically new approach to the design of batteries, developed by researchers at MIT, could provide a lightweight and inexpensive alternative to existing batteries for electric vehicles and the power grid. The technology could even make 'refueling' such batteries as quick and easy as pumping gas into a conventional car (abstract). The new battery relies on an innovative architecture called a semi-solid flow cell, in which solid particles are suspended in a carrier liquid and pumped through the system. In this design, the battery’s active components — the positive and negative electrodes, or cathodes and anodes — are composed of particles suspended in a liquid electrolyte. These two different suspensions are pumped through systems separated by a filter, such as a thin porous membrane."
Wesley Snipes Flashbacks (Score:1)
Dang it... (Demolition Man) (Score:3)
You beat me to it.
The idea has been around a long time, but making it work is a wholly different kettle of electromotive potential.
Fuel cell? (Score:2)
Nope, not a fuel cell. Nothing is consumed. (Score:5, Informative)
A fuel cell basically "burns" (uses up) its reagent to make electricity directly.
This (according to the article) is a reversible reaction between two liquids, one acting as an anode and one acting as a cathode, where the reaction is bounded by a membrane. It is really more of the "capacitance gel" idea, only with two carries (which makes sense).
Think of it as two halves of a standard battery that can only interact when brought into proximity. While electrons (or maybe ions or something beyond my simple ability translate, not having seen the research or studied in the field) pass through the membrane by definition, the idea is that the charged medium is not part of the fixed assembly, so the fixed assembly (the reactor and membrane) is permanent while the charged part moves.
In a standard battery the anode and cathode are permanent parts of the battery. When the battery is discharged the whole battery is trashed. For instance, and alkaline battery is assembled in a charged state, the dissolving of the metals in the alkaline solution is what makes the voltage. Lead-acid batteries wear out because the lead is changed by the charging process (applying voltage in the presence of acid solution) and changed back by the discharge. This cycling slowly causes the lead to flake and degrade until there is either so much lead flakes in the battery that a cell shorts out because of the lead connecting the two parts, or the odd chemical impurities and available oxygen slowly make the lead into a chemical that will not react with the acid correctly any more.
In this arrangement the parts that would degrade are in the fluids, draining and replacing the fluids "assembles a new, fully charged battery". In this model the ideal of pulling into a service station and replacing your discharged battery pack with a new, charged one, becomes practical.
In the alternate, as a rechargeable battery the non-solid nature of the battery itself lets the battery be charged and cooled all at once. The anode and cathode material won't "flake" because it isn't sold to begin with. Plus nearly all of the anode and cathode material is used by weight, there is no "inner core" area acting as a superstructure. This should improve the energy density (how many kilowatt hours you can store per pound etc).
In the rechargeable battery usage the battery would probably need to be changed regularly, like an oil change, but _then_ one could probably use charged plates to separate/filter the degraded particles from the good ones, so the "battery" could be recycled in place instead of having to take it back to a factory.
There is a lot potential wins here, but it is _very_ unlike a fuel cell.
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Re:Nope, not a fuel cell. Nothing is consumed (Score:1)
"A fuel cell basically "burns" (uses up) its reagent to make electricity directly."
Going to have to disagree with you here, a fuel cell is an electrochemical energy conversion device, which use a chemical reaction (in most cases a redox) to convert chemical bond energy to electrical energy. Generally this is run in one direction only, for instance hydrogen plus oxygen goes to water vapor and electricity. However, fuel cells by nature (not necessarily engineered for) are completely reversible. You can app
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Not quite. The fuel cell consumes fuel and an oxidizer in an electrochemical reaction. This is more a rechargable battery where anode and cathode are thick liquids. Unlike a fuel cell, if you exchange the liquids out, the spent ones can then be recharged in another battery. You can also just recharge it if you have the time.
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I sure hope they can develop this concept into a design that can be used by consumers.
Get prepared for plenty of toxic waste spills. I did some research on vanadium flow batteries a decade or so ago, and they're just too toxic for the average redneck or the average MBA to be placed in charge of. Like giving matches to a little kid.
The bad news is the vanadium-based chemistries are probably the safest, least reactive, least corrosive of the flow batteries. The others are worse. Lithium chemistries that occasionally burst into flame, iron based chemistries that are basically controlled rus
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Well, we are talking scales and scales here. The energy density of gasoline is still about a 100 times higher than that of the best batteries available. And it's not like there hasn't been any research on batteries.
Nitpic: the market for electric model airplanes took off before, with the NiMH cells. Of course, LiPo batteries are a lot nicer still.
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Of course, one mitigating benefit is that electric motors weigh far less than gasoline-powered ones do, and are more efficient.
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The batteries might bring the weight right back up and higher than an ICE vehicle however, for example the Lotus Elise vs Tesla Roadster. The Tesla weighs about 500lbs more.
However that uses relatively heavy (compared to other modern technologies) Li-ion batteries, Li-pos are much lighter, and I don't know how much this new battery type will weigh.
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- NiMH planes were hardly a joke. There was a lot of airracing done with them. Worked well.
- Many model planes get a lot of time out of their LiPo batteries, making the pilot want to have a break before the battery is empty. Gas, of course, runs much longer and you can sustain power for longer, but often the drawbacks (the mess) dominate.
Still, flying most distances of interest with a useful load is off limits for batteries.
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With a useful load is the real trick to electric anything.
Sure you can have an electric car today. Try loading up 2-3 of your friends, luggage for 4-5 days, to go anywhere?
The few cars that might get 200 mile range are suddenly cut down to 75.
Electric will come when two things happen. Better energy storage, and people get over nuclear power fears. With out nuclear power generation electric cars are worthless. Solar, wind hydro, geothermal, tidal, won't produce enough power to cover current needs, let al
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If my math is right, you're off by nearly a factor of 10.
To replace every ICE passenger vehicle in America with an EV with double the battery capacity of the Nissan Leaf would increase annual US electric consumption by 40% not a 300% increase by replacing only a third.
Passenger vehicles in US incl SUVs = approx 250,000,000 (2006)
Nissan Leaf battery capacity is 24 kWH so double = 48kWh
Assume full charge every 3 days so annual # of fillups = 120
(The vehicle number is somewhat low but the charging and capac
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Not at all - he made a clear mistatement or miscalculation. Yes, there is a hell of a lot of energy content in our liquid fuels but since a fairly small percentage actually moves the vehicle versus heating the engine, it's not a one-to-one replacement. A gallon of gasoline has more energy than a fully charged Nissan Leaf but I don't know any comparable street legal cars that'll get 100 mpg.
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Yes, for now, real travel requires a "real" car. However, most car trips are short commute and shopping mall trips with 1 person in the car. Where electric would be more efficient than gas.
Electric will come when it's the most attractive alternative financially, i.e. when gas prices go high enough.
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could (Score:2)
I hate the word "could." It's so inconclusive. I always think of the Geico commercial. "15 minutes could save you 15 percent or more on your car insurance." Yeah, and if I buy a lottery ticket, I could win millions of dollars. I probably won't, but I could.
I'm probably just being too cynical. This is an interesting development, and I should be more supportive. But I can't get excited when there's so much "could" in an article. Just not in my nature.
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At least Geico's honest. Everyone else says that people who switch to them "save hundreds."
Well fucking DUH. Why the hell ELSE would you switch?!
(One cynic to another)
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Though completely off-topic, another reason people often save money when switching car insurance is that their cars are re-valued in the process. Of course, the car's current value is less than it was when the first insurance was purchased.
Dangerous in the wild (Score:4, Interesting)
Don't spill that shit. Imagine the average "I always top off my tank" bone head at a "gas pump" spilling what is basically the first practical, room temprature binary explosive all over the outside of his Jetta. Granted it isn't a proper explosive, it would be more of a flash of heat and electrical potential as the two materials mixed without the interleaving membrane.
As a sealed cell this is a fine idea. As a dispensed material it has "technical issues".
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Could mean the end of self-serve pumps.
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Not sure full service helps. The only time I've seen someone spill gas all over the ground is the guy at a full service pump. I've never done it myself.
About spilling gas, you wanna read this... (Score:2)
After borrowing my father's 4WD (not some big city pretender, but a proper off roader, diesel, 2 tanks, etc.) I went to fill it up as thanks. So, I filled up the 1st tank with 75 litres. Then I started fillling up the 2nd tank, and at about 20 litres, this passer by points out some liquid on the ground. I looked around and found that I'd stuck the bowser into a hole in the wall of the car for connecting water. Literally just a hole in the side of the car. So I had filled the car floor with 20 litres of
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Or it just means that the pump nozzle will have to plug into the fill port creating a liquid tight seal. There would also be a better over flow sensor to shut off the pump when the tank is full.
Though, that means there will have to be a standardized fill port plug and it would have to accommodate both cars and heavy trucks.
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That would be _FOUR_ liquids passing through the nozzle, not just one. Anode Charged and Cathode Charged going in, Anode Discharged and Cathode Discharged coming out. Mixing of the two charged liquids is the part I think would be hugely dangerous. Small amounts would invariably leak out in traces, and it only takes a some kid going "what's that daddy" for someone to touch the residue of both ports and shock or burn themselves.
Closed systems would be much safer.
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Honestly you would never get people to switch to gasoline today because of "safety concerns".
Not "Flaimbait", just flames... (Score:2)
I love this moderation... it shoudl be +1 Flaimbait as any arrangement where four fluids (two charged fluids going in, and two discharged fluids coming out) of varying electrical potentials are being exchanged by someone of the same technical competence as, say, my mother, is _bound_ to end in flames, or at least tears... So having my mom pump this stuff, were she still alive, would be baiting flames indeed.
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Do you really think that will be possible? The nozzle is already going to have to be different (since it's a binary compound) so they're going to have to redesign refueling anyway; if this goes commercial, they would build in safeguards against that, along with safeguards against accidentally putting some in your gas tank
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Oh come on. Do you think LPG is tanked the same way petrol is? There already are working, foolproof, airtight connectors. You just need another one, that has four tubes - 2 in, 2 out. Add some sensors and you're off.
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They'll have to make damned sure you can't accidentally add cathode to the anode tank or vice versa or it'll be like the Dell laptop scaled up to OMG RUN size.
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I've seen the sign.... and heard the gurgle as the froth from pumping a liquid at 5GPM settles down into the oddly-shaped, baffled tank.
WTF shitty gas station do you go to where topping up leads to gas on the ground? I've only done that ONCE in my life, and it was because the gas station didn't properly maintain their pumps.
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Topping off leads to gas on the ground all the time. Look at the ground at your gas station, heck lick it (I cannot honestly recommend touching the ground with a light lighter but it _would_ be funny) and see if you can see or taste gas. That stuff comes from somewhere, and it isn't just the disk-shake-drop that most people leave when they pull out too soon.
A wait ten seconds and then trickle-pump some more top-off can be done with predictable results. It's never necessary. Most people who top off make a me
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That's not "topping off" (Score:2)
If you know your tank isn't anywhere near full, then you are not "topping off" technically or morally, you are continuing to fill your tank.
There are two primary reasons that the nozzle will trip "for no reason". (1) improperly inserted nozzles will self trip when their stream of gas hits the side of the pipe and causes back-pressure, and likewise for letting the nozzle back out of the pipe. (2) Someone before you topped off and got "just a little" liquid gas into the vapor recovery system, when those liqui
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I don't think it's fair to call it idiocy, it's simple misinformation.
They probably figure that the more fuel they put in now, the more they can drive before having to refill again.
In my defense, I don't top off for two reasons: 1) those extra drops don't mean much in terms of extra distance traveled, and 2) some guy at a gas station one topped my tank so much that it blocked the fuel meter at half full until I used up the fuel in the tank until that level. On a related note, never buy Peugeot.
But I'd never
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Oh you'll know it if it hits the ground. There is no secret hole it comes out of where you won't see it.
The thing you are likely not to see is when the fule gets sucked into the vapor recovery system. If there is a big hood thing you will see it clearly when you separate the noces and tank. If its the kind where there are a bunch of holes around the outside of the tip of the nozzle then a slow-fill top-off may send a non-trivial amount of that gas you are pumping back into the pump.
There is an ongoing desig
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In which case you leave it off for a few seconds to let it settle and try again. And yes, you should know roughly how much gas you need. The capacity of the gas tank is in the manual for a reason and assuming it's roughly linear, ought to be able to figure out how much gas you need from both the gauge and the distance travelled.
The skill is particularly important these days as it's
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all those spills on the ground are caused by lawncare/ ATV people topping off secondary tanks.
Watch a truck pull into a gas station hauling three lawn mowers with 3 5 gallon spare tanks on the ground, and them climbing on the lawn mowers to top those off too.
or people hauling their boats and topping off at the gas station as it is cheaper, if not easier.
There is lots of reasons gas spills at gas stations.
Topping Off, An Aphrophal Correction (Score:5, Interesting)
There is a reason it's called "topping off" if my father's long-ago explanation is to be believed...
First: there is no "drain hole" in the fuel system (at least in the US etc) since the fuel system is supposed to be vapor tight. There _is_ a small drain hole behind the typical fuel filler door which mostly exists to prevent water from getting caught inside the compartment and rusting things out. That said...
We pump gas _far_ too fast to be environmentally sound. It _froths_ out of the hose in a turbulent flow and a lot of vapor escapes because of the frothing, which is why we now have those vapor recovery hoods etc on a lot of pumps.
When the tank is nearly full, e.g. "as full as it ought to be", the froth boils up the fill-pipe and triggers the back-pressure sensor causing the nozzle to click closed. I few seconds latter the frothing settles and there is now a space in the tank. "Topping off" is the attempt to fill that space.
Back in the before time, that is, before gas was expensive and mileage was important, getting that quarter of a gallon into the car meant getting another three or four miles before needing to fill up. Nobody cared that the net effect was 3 cents of gas gushing out of the pipe and onto the ground because everybody thought "what the heck" because nobody knew that dispersing hydrocarbons did anything but smell nice and industrial. Plus gas fill points were low and typically at the bumper so it didn't even ruin the paint job.
Now days, "topping off" is as bad as it ever was, and worse too boot. The attempt to fill that last little bit not only causes gas to gush out onto your paint job, and pollute the environment, not it also can put liquid gasoline into the vapor recovery system. This can cause the back-pressure valve in the pump to "miss" the fact that froth is rising in the fill tube. You can end up pumping gas right back out of your car and into the gas station tanks ( this costs you money) and then when you separate the nozzle from the car a _lot_ of gas can have collected in that rubber hood thing which then goes everywhere.
Better yet, then next guy will get the same treatment if there is still liquid gas in the vapor recovery system. I filled up my Prius in a bad part of town the other day, and when I pulled the nozzle out, a good 3 cups of gas went everywhere. Some person before me must have "topped off" and that turned the vapor recovery system into a siphon. Who knows how many people that effected before me, and after as now _my_ gas was in the hose for the next guy.
Your gas tank is never supposed to be _full_ by absolute measure. Just like every other container of liquid you have ever dealt with, there is a little space at the top.
Topping off _any_ container is the act of trying to fill that last little bit between "properly full" and "absolutely full" and it _always_ results in waste and spillage due to over-filling.
In my grandfather's age, the tank wasn't full until some spilled out. Topping off was the norm. People still do it because that's how they learned to do it "no matter what the sign says, my daddy showed me good"; this is the law of the dumb.
Re:Topping Off, An Apocryphal Correction (Score:2)
And one way or another, when you fill that canteen you either leave/trap a little air or waste some water due to overspill. In fact I bet you often do both.
And the word I meant to put in the subject was "Apocryphal"...
Not to be pedantic. Twice. 8-)
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At this point, that extra gas goes out of a little overflow hole, and typically runs down and onto the ground
I'm quite skeptical of your claim. How is it legal to make a car that intentionally leaks gas, especially in a non-obvious way? Also, how is it that I've seen gas spill out of the port (is that the right word?) used to insert the nozzle? Is the overflow hole an insufficient size for its intent?
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I always let the pump run at full speed until it clicks off, then wait about 10 seconds and run it at full speed until it clicks off again.
Due to the design of my car's tank etc., this means I can usually get another 1-1.5 litres in there. I haven't had a spill, yet.
Actually, no... but not a "stopper". (Score:2)
I would expect a standardized interlocking cartridge thing, or in-place charging.
In the case of replacing the fluids:
(1) The quantity of the two liquids would need to be kept in balance, which would be very hard to do using a "pumping" paradigm.
(2) The liquid isn't "consumed" (e.g. burnt) so much as "exhausted" (reduced to a non-charged state) so the spent liquid would need to be returned at the same time as the new liquid is supplied, which would get you up to four connections in the system instead of two.
Nothing new (Score:1)
Radically new approach? (Score:2)
It's hardly a "radically new approach". The idea has been around for a long time and is easy to come up with off the the top of your head. I did in
this slashdot post [slashdot.org]. I'm not going to try to claim to have come up with a radically new approach there either since the idea has, in all likelihood, been around for about as long as batteries have (which is millenia, incidentally). Making it work is another matter altogether. If they have, it may be of some interest. Of course, in the post I linked to above, I spe
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You have a high opinion of major metropolitan areas...
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Hard to tell which is more important: groundwater or air. I was actually arguing for sealed batteries as opposed to liquid flow battery juice. Concentrating the job of filling batteries with highly reactive heavy metal containing liquid compounds seems like a job best done in a small number of well-regulated facilities with serious containment and trained, careful personnel rather than at tens of thousands of little stations maybe inspected once every few years with the filling done by commuters in a rush o
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Yes, the point is that the heavy metal loaded run off from these will be even worse than what ends up under the gas stations now. And yes, I have a point. I've already stated it too. The point is that sealed batteries would probably be a much more environmentally sound idea than filling up with liquid battery juice.
How about... (Score:2)
Instead of refueling a battery, you change the whole battery every time you stop at a "gas" station. The system has been used for gas cans for decades now and it works.
I always wondered why do they assume that a car battery needs to be the same every time.
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I'm not sure comparing 30lbm propane gas cylinder swaps to swapping batteries is a fair comparison. (Assuming that's what you meant; I'm not aware of anywhere that swaps gasoline cans.)
That said, there are many groups working on swappable battery packs. Part of the problem, though, is that you have structural issues, alignment issues, storage issues (it's a lot easier to store and move liquids than it is 100+ lbm battery packs), matching the correct battery pack to the correct vehicle, and issues like makin
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That is the basic idea, but it's really simple:
I've seen working prototypes with working swappable batteries, so that shouldn't be an issue.
Same way every car either takes leaded gasoline, unleaded gasoline or diesel, just make 3 types of batteries (different power for different requirements).
The management part should be possible to overcome, especially because the adoption would be slow. The infrastructure would have to be built, but that doesn't meant it isn't doable. The up side is that you wouldn't req
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It's a bit like where we would be if we had at this moment just discovered petroleum as a viable engine fuel, but for some reason what we actually have in production is tar. Tar has terrible viscosity and it doesn't make a very g
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Trick is, a natural gas tank is just a can full of natural gas. and 30 pounds of natural gas is pretty much like any 30 pounds of natural gas.
Batteries, on the other hand, age. As they get older, they hold less energy. So, you take your brand new battery (which you paid a pretty penny for when you bought your new electric car, and which w
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I think of it like a propane tank for a gas-fired barbeque grill:
It's (usually) cheaper to refill the same tank over and over, but that takes more time, and can only be done at a limited selection of locations. Plus you've got to keep the thing free of rust, have it inspected periodically, and sometimes apply a new coat of paint. Eventually, the tank will fail inspection anyway, and needs replaced.
And while some folks do all that, others just toss their empty tank into the car, and exchange it for a full
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There was a little Italian electric sports car that did exactly this. The trailer even had active steering so that it would always be directly behind the car.
hurray (Score:1)
another amazing, wonderful, world changing, society fixing, all or our problems are solved, idea i heard about this week that ill be wondering what the hell ever happened to.... ten years from now when gas is $50/gallon to power a car that still doesnt fly and my cell phone charge still wont last more then an hour and all my friends are still obese and dying from cancer, lack of health care, with an upside down mortgage and no jobs and a microwave dinner that still fucking frozen in the middle.
someday you s
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yeah i came off critical of mit or something, i was really bugging more about tech journalism and OMG THE FUTURE!!! eeehhh .
It's got what cars crave... (Score:2, Funny)
It's got electrolytes!
Better than public transportation (Score:4, Insightful)
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2009 figures for U.S.: more than 2/3 from fossil fuels:
coal 44.9%
natural gas 23.4%
nuclear 20.3%
hydroelectric 6.9%
other renewables 3.6%
petroleum 1.0%
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And where will the electricity come from? Oil is energy; transportable and relatively dense, but it still accounts for more than 35% of US energy use. A "transition... to all electric" does not mean energy independence anymore than a "hydrogen economy" does.
I expect electricity generation to get cleaner, greener, and cheaper over the next 100 years as we finally figure out safe nuclear that can run without lies and coverups.
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Not for the US. The vast majority of our oil comes from Canada, Mexico, Venezuala, and other locations in the Americas.
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Right, but cars do work very well for the majority of this country's 300 million population. Only a small fraction have to live in the overcrowded metroxplexes that do not have adequate road systems for their populations.
Ever tried driving a car in say, Lubbock, Texas? It works AMAZINGLY well. You can get anywhere in the city you want in 15 minutes, and delays are minimal.
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Its worth noting that approximately 60% of the US population lives in cities of 200,000 people and above. Lubbock, at 60,000 people in spacious (and relatively recently developed) West Texas, is actually quite different.
Source: http://www.fhwa.dot.gov/planning/census_issues/metropolitan_planning/cps2k.cfm [dot.gov]
Am I the only one who saw this? (Score:4, Insightful)
This BS needs to stop. Repeal the Bayh-Dole Act [wikipedia.org]. It has done nothing but harm the public and our economy.
Re:Am I the only one who saw this? (Score:4, Interesting)
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You can either have academic labs researching things which are commercially interesting, and then give the professors working on it the perk of having the opportunity to commercialize it first (or at least royalties), or you can have academic labs researching things which the professor is academically interested in, and hope that it is commercially interesting. It is difficult to get both.
Either you get people complaining that publicly funded research isn't free to the public to use, or you get people compl
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Like how private trucks drive on public roads, and the government hires contractors to build infrastructure with tax money? You're a moron.
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"As for there getting 'first dibs', where did they get the resources and right for 'first dibs'?"
It's called the Bayh-Dole Act, and it's an abomination. It was well-intended, I think, but it had unintended consequences.
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Another "upside" of this technology... (Score:2)
Various governments around the world can impose a tax on the liquid, effectively being able to keep that huge income stream intact. When the price at the pump is 75% tax (in my glorious socialist EU country), at 1,70€/liter...
Electric cars can use 20Amp 3-phase chargers to charge the batteries (albeit slowly) without requiring any changes in the electrical systems of a house. This makes government budget centers iffy, since they cannot easily tax you (despite the fact that in many EU countries you alre
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At-home charging doesn't help when you're driving a distance larger than a single fill-up range. Nor does any charging scheme where the wait time is significant.
There is a legitimate market for fuel substitutes that are easily flowed in & out of a vehicle.
The Keywords Are "Lightweight and Inexpensive" (Score:1)
Am I the only one who thought... (Score:2)
Pre-peer puffery (Score:3)
"The new semi-solid flow batteries pioneered by Chiang and colleagues overcome this limitation, providing a 10-fold improvement in energy density over present liquid flow-batteries, and lower-cost manufacturing than conventional lithium-ion batteries."
It's statements like this that make me cringe when I look at the puffery which comes out of academia. 10 * better than A, and cheaper than B. Is it 10 * better than B? Or as good as B? Or (more likely) 1/10th as good as B.
Charge time isn't the problem (Score:2)
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I think many people would choose to charge at home while their car is in the garage. Filling stations would be most often used for longer trips which is the vast minority of vehicles on the road.
Also, yes electric motors generate heat. If that electricity came from solar, you know where most of the energy would have gone were it not for the solar collection? Heat. A tiny bit of reflection might escape the planet, but it would mostly go to heat.
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Interesting idea, with some flaws (Score:3)
I just read the Advanced Energy Materials article (which you can easily find by googling the title and filtering for pdf).
The idea itself is interesting, and could potentially remove some manufacturing problems (i.e. no need to dry, calender, cut electrodes and then assemble single cells and wire them in a pack) but I see a couple of big flaws in it:
1) Let's get off the table the idea of "refueling". Li-ion batteries are assembled in their discharged state. The slurries containing LiCoO2 and Li4Ti5O12 (as per the article), when put in contact, produce exactly 0 energy. You have to either charge them using electricity, or prepare slurries of Li0.5CoO2 and Li7Ti5O12. Neither of the two materials is stable in air, thus I don't think it's possible to prepare a "refueling" system with current Li-ion battery materials.
2) The beauty of Li-ion batteries is that they have 99.995% efficiency round-trip. This system seems to be based on very thick slurries which probably require strong pumps to circulate in a system, thus killing such efficiency.
3) What's more, the slurries are prepared with highly flammable solvents (dioxolane). Not sure I'd like to carry around two tanks of the stuff, considering that a breach in the separator or in the "fuel" lines could ignite the whole thing.
It is true that changing materials is a simpler problem than designing a completely new system, but as the authors themselves admit this is just a readaptation of an old system.
I think it would be much more practical to redesign redox flow batteries to use non-aqueous electrolytes, thus allowing to work in a larger potential window (water only allows about 1.5V).
I'm not sure things are looking up for A123, and I hope Prof. Chiang won't sink with this idea either. Good luck to all the researchers involved.
honey ... (Score:1)
Not really that new. (Score:1)
The only difference in this one is that the reacting material is a suspended, particular solid. There are commercial systems that use flow through batteries already.
See:
Flow batteries have historically had low energy densities, as the entire reacting mass was in solution. E.g. the article above cites 25-75 Wh/kg
Which means a 50 kWh system would require roughly a cubic meter of tank, or about 5 standard drums. This is acceptable for a house, unworkable for a car. (50 kWh is about 2 days average power f
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Nope. The anode and cathode in a car battery are lead/lead oxide/lead sulfate plates. There's an aqueous electrolyte, like in any wet cell battery.
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quick and easy, sure, but not the same at all. (Score:2)
Two fluids, out and in, reduce the mixing so that the fresh fluid is not diluted unacceptably by the stale, ensure none of the anode fluid _ever_ mixes with the cathode fluid, ensure that no person (including a curious child) is exposed to both fluids at once even if they "poke at" the nozzle. This is not a "fill the tank with gas" analog operation at all.
I think the material has great promise, and since it is fluid based, it is probably very able to be cooled quickly as it charges so a closed-loop fast cha
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You remember Atari cartridges and cartridge slots that had flaps that protected the connectors and made them difficult to accidentally touch? Use something like that. Inside have a connector that only fits on one way.
For replacing the fluid, you can have a switch or data interface for the pump to tell the car to go into "charging mode" that opens any valves and opens a small bypass around any pumps so that the station pump can force new electrolyte through the system. That is if it needs to be air-free at a
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It is, because the 'recharging' occurs at the 'petrol' station long after you've left.
Its then pumped in to someone else's car.