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Power Cellphones

Nanodot-Based Smartphone Battery Recharges In 30 Seconds 227

Zothecula (1870348) writes "At Microsoft's Think Next symposium in Tel Aviv, Israeli startup StoreDot has demonstrated the prototype of a nanodot-based smartphone battery it claims can fully charge in just under 30 seconds. With the company having plans for mass production, this technology could change the way we interact with portable electronics, and perhaps even help realize the dream of a fast-charging electric car."
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Nanodot-Based Smartphone Battery Recharges In 30 Seconds

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  • by digsbo ( 1292334 ) on Monday April 07, 2014 @10:50AM (#46684403)
    TFA states that they would need to substantially improve current capabilities for a car-size battery. Not that it doesn't make it cool, but at the same time, it's a bit presumptive to assume this will be the basis of car batteries given existing capabilities. Good luck to them, though!
    • by Alioth ( 221270 ) <no@spam> on Monday April 07, 2014 @11:13AM (#46684715) Journal

      It's irrelevant if they do this anyway, because if you had a 100kWh car battery that could charge in 5 minutes, the voltage and current requirements would be so enormous to make it impractical, because you'd have to deliver 1.2MW to charge the battery in that time. At 11000 volts you'd still require a current of about 110 amps, so not only very high current, but very high voltage.

      One of Britain's largest single generating plants is the Sizewell B PWR nuclear generator, rated at 1200MW. It would take just 1000 such cars all wanting to charge at once to completely use all the capacity of this entire large nuclear power station. How many cars are currently filling up with petrol in Suffolk (the county where SIzewell B is situated) right at this second? Probably well over 1000.

      • Re: (Score:2, Funny)

        you'd have to deliver 1.2MW to charge the battery in that time

        As I read that quickly, I got excited and then realized I was reading it wrong and you did not state that you'd need to deliver 1.21 gigawatts.

      • you'd have to deliver 1.2MW to charge the battery in that time.

        Megawatt industrial motors and pumps are common. A home charger could not do deliver this much power, but a charging station along a freeway could. If you are at home, it is unlikely that you need a super fast charge anyway.

        How many cars are currently filling up with petrol in Suffolk

        Wrong comparison. How many of those cars need to be filled in 30 seconds? As we switch to electric vehicles, >95% of the charging will be done over several hours while parked at home or work. Those chargers will also have enough intelligence to suspend charging if there is a sudd

      • It's irrelevant if they do this anyway, because if you had a 100kWh car battery that could charge in 5 minutes, the voltage and current requirements would be so enormous to make it impractical, because you'd have to deliver 1.2MW to charge the battery in that time. At 11000 volts you'd still require a current of about 110 amps, so not only very high current, but very high voltage.

        Don't forget that if the process is even 10% inefficient then that's a 120kW heater underneath your car. Winding the windows down while you're charging probably won't be enough cooling to keep the passengers alive.

        • That's not horrible... just 1200 lightbulbs. You could protect the occupants with some space shuttle tiles or any ablative impregnated carbon shielding you might have sitting around the house.

      • by AmiMoJo ( 196126 ) *

        Most people don't run their electric cars down to zero though, they top up at home and at work. The only time someone would want to do a full charge in five minutes is when making a long journey when they absolutely can't afford to stop for say 30 or 50 minutes and must get 100% capacity in order to drive for another four hours solid.

        Realistically the current 30 minutes for 180 miles range or 50 minutes for a full 300 mile range charge that Tesla offers is more than adequate for most people. As EVs get more

        • Realistically the current 30 minutes for 180 miles range or 50 minutes for a full 300 mile range charge that Tesla offers is more than adequate for most people.

          I think it is close but they probably need to cut the 30 minute time in half before people will be ok with it. 30 minutes is a pretty long time to stand around your car waiting for it to charge. It's fine if you are stopping for a long break but I don't really need to stop for a half hour or more every 3 hours of driving. My current car can go from Detroit to Cleveland and about halfway back on a single tank and if I need to stop it is a 5-10 minute deal. A Telsa could usually make the trip one way (bar

      • How many cars are currently filling up with petrol in Suffolk (the county where SIzewell B is situated) right at this second?

        Yes, this is the point that all the electric car makers either miss or ignore.

        Petrol has a massive energy density (party due to being able to use air as a "free" oxidiser). In simple energy terms it "contains" about 33M Joules per litre - or 2GJ in a standard tankful. Try to transfer 2GJ of energy into an electric car's battery in the time it takes to fill your tank and you realise just how convenient a liquid fuel is.

      • by Cyberax ( 705495 )
        That's not entirely correct. Most people will still charge at home during the night. Super-fast charging is probably going to be used only for long-distance travel.
      • by jcochran ( 309950 ) on Monday April 07, 2014 @12:54PM (#46685871)

        You forgot the obvious solution since a service station doesn't need to handle a lot of cars at once. Namely have the service station hold its own set of batteries. These batteries can be "slow charged" based upon the available power. Then when a car pulls up needing a fast charge, the station batteries can do the job. Yes, this will cause an extra layer of inefficiency, but it should be quite doable.

        • Exactly. I fail to understand how someone can be smart enough to think of the shortcomings of super fast charging without being fast enough to think of the obvious solution of batteries in between the power station and the car charger. Suggests either extreme laziness or some kind of agenda.

          • Er I meant "without being *smart* enought", not "*fast* enough". In this case I guess I was too fast to hit submit. Or maybe just not smart enough to re-read properly before submitting?

            By the way Slashdot's post rate limiting is completely dumb. It's now been 2+ minutes since I submitted my comment and I can't post this correction yet. Hey Slashdot, how about implementing an 'edit post' button! Welcome to the 2000's!

          • ...because I don't want to drive off with someone else's $20,000 dud battery...
      • I'm going to have to go with 'gas' stations being fitted with capacitors that charge continually, and discharge rapidly each time a car plugs in to it.

      • I get 12MW to charge a 100kWh battery in 30s. Your nuclear generator would only be able to charge 100 cars simultaneously.

        But if you relax the requirements, it isn't quite as bad. It's unlikely anyone is going to fully run down their battery, and I also believe EVs like Teslas don't ever fully charge their batteries either, in fact it appears they recommend not to fully charge it unless you really need the full range, as fully charging it reduces its lifespan faster (someone correct me if I'm wrong). Any

  • Phones yeah (Score:5, Informative)

    by 3.5 stripes ( 578410 ) on Monday April 07, 2014 @10:51AM (#46684423)

    I'm not sure charge speed is so important for cars, I'd imagine that reducing the battery weight and size would be more important.. having twice or three times the capacity in the same space would be much more important than charging fast, especially considering how much power you'd have to put through a cable/connector to charge EV batteries in under an hour (as an example)..

    • Re:Phones yeah (Score:5, Insightful)

      by Nemyst ( 1383049 ) on Monday April 07, 2014 @10:57AM (#46684497) Homepage
      Very fast charge (on the order of 1-2 mins for current battery sizes) would make "gas stations" viable for electric cars. It'd immediately remove the current big stumbling block, which is that once your capacity is depleted you need to wait for a few hours to recharge. Bigger capacity would be nice, but it'd just delay the issue. Fast recharge would let current gas stations convert to electric, allowing us to reuse existing infrastructure and easing the transition between gas and electric.
      • Going to need superconducting charge cables. My mom sure isn't going to be wrestling 00 gauge charge cables into a connector.

        They aren't looking at battery swaps because charge time is an easy problem to solve. Even if the batteries were done, there would be technical and safety challenges.

        • by Mr D from 63 ( 3395377 ) on Monday April 07, 2014 @11:28AM (#46684887)

          Going to need superconducting charge cables. My mom sure isn't going to be wrestling 00 gauge charge cables into a connector.

          >

          No problem, we'll just 3D print em'. 3D printing will solve all our problems.

          For that matter, why don't we just 3D print a fully charged battery?

        • They aren't looking at charge swaps because the infrastructure cost is enormous. Better Place tried it in Israel (much smaller country with more political incentive for EV use) and went bankrupt because people really didn't need swaps as much as they thought they would, and because they could only get one model of car to use the compatible battery.

          It's hard enough getting people to roll out the standard charging stations we have now and keeping them all operational, can you imagine getting 100x that inves

        • Going to need superconducting charge cables. My mom sure isn't going to be wrestling 00 gauge charge cables into a connector.

          There are already prototype robotic gas pumps. The hardest part is opening the gas cap on all the different models. If the electric connector on cars is standardized, then robotic electric charging stations should be easy. So your mom can sit in her air-conditioned car and listen to the radio, without touching any cables.

        • by Prune ( 557140 )
          00 gauge isn't anywhere close to cutting it, even if you're running this at a few kV. GP poster simply didn't think this through when rushing to post.
        • by AmiMoJo ( 196126 ) *

          Charge time is solved for most people. I'm surprised Tesla is bothering with battery swaps. I expect it is just to shut up the doubters and get some good PR.

        • by afidel ( 530433 )

          480V 600A cables are smaller in diameter than current gasoline lines and probably not that much heavier per meter, though that would take ~20 minutes to fill a 100kw battery instead of 3-5 minutes for a gasoline fillup.

        • My mom sure isn't going to be wrestling 00 gauge charge cables into a connector.

          Years ago, they had these things called "Gas Station Attendants."

          Just sayin'...

          • by lgw ( 121541 )

            Is this progress? Moving from 1-minute fill up to 20 minutes and it requires an attendant? Not in my book.

            I can see the appeal of a plug-in hybrid: charge at home for short trips, a great 80% solution, gas for everything else.

      • Very fast charge (on the order of 1-2 mins for current battery sizes) would make "gas stations" viable for electric cars.

        You've done the calculation for how many amps that would need, right...?

      • by nojayuk ( 567177 )

        Fast-charging an 85kW battery, the same capacity as fitted to the Tesla S, from 20% to full in five minutes would take about 700kW or roughly the power feed for thirty-five typical US homes (100A @ 200V). If the "gas" station wanted to charge two batteries at the same time then double that figure. Halve the charge time to two minutes, double the power feed rating again. Assuming 400V battery packs a 2-minute fast charge unit would require connectors and cables rated to handle about 10,000 amps.

        Folks don't

        • by AmiMoJo ( 196126 ) *

          The difference is that you can charge your car at home, at work, at the car park or pretty much anywhere that has electricity. There isn't the bottleneck of everyone having to go to the petrol station and fill their tank any more. Most people will just charge overnight when electricity is cheap and never normally visit a Supercharger, because they don't drive 250+ miles a day.

          • by nojayuk ( 567177 )

            I live in a block of flats, I don't have a garage or other place to plug in a car to charge it on a regular basis. I'd have to visit a local supermarket car park which has two electric vehicle charging bays at the moment to charge an electric car if I owned one. It's about a kilometre from home on foot and the car park rules only allow me to park there for two hours at a time before I'd have to pay penalty fees of up to £80 a day. That's assuming either of those bays is free when I get there of course

      • by Alioth ( 221270 )

        Very fast charge is also completely impractical for cars with any forseeable technology. To charge the (relatively small, with only a couple of hundred miles range) 85kWh Tesla battery in 1 minute would require 5.1 megawatts of power to be delivered by the charging cable. Even at 11,000 volts you'd be looking at over 460 amps to do that. The largest power station in the USA is 6800MW (Grand Coulee) and would only be able to simultaneously charge 1334 cars assuming no transmission losses.

        Quick charging beyon

        • So, use a big, braided, heavily insulated cable. With a connector about the size and weight of a gas-pump nozzle.

          Now, neighborhoods won't want huge high-tension lines running to every corner "gas" station. But, no worries, we have these cool new high-rate high-capacity batteries! You just load a semi truck with them, and put on REALLY big (a few square feet) charge/discharge connectors. The truck charges up at the generation facility, drives to the local station, and discharges into the station's below-grou

          • Why not have capacitors (or batteries like these) that can slowly charge up from the grid and then quickly discharge to quick-charge a car? Multiple banks of them could allow a few cars to quick-charge in sequence without leaving the next customer SOL.

        • Re:Phones yeah (Score:4, Insightful)

          by robot256 ( 1635039 ) on Monday April 07, 2014 @11:51AM (#46685199)

          It probably also demonstrates something about how energy profligate that personal motor transportation really is.

          Yes it does, especially when you consider that electric vehicles are 80% efficient compared to 20%-efficient gas cars.

      • For cars any fast-charge battery doesn't remove the *ahem* "current" stumbling block but rather *moves* it.

        Tesla's fast-charger claims a 4-hour recharge on a charger pulling 16.8kW and a charge will get you rougly halfway from San Francisco to LA - a trip easily made on a tank of gas.

        To match a gas-station fillup you would need to transfer that amount of energy in about 5 minutes requiring a supply of a touch over 800kW. At 600VDC - the voltage used by BART - your cables would *only* need to carry about 1,3

        • Re:Phones yeah (Score:4, Insightful)

          by GameboyRMH ( 1153867 ) <gameboyrmh AT gmail DOT com> on Monday April 07, 2014 @01:16PM (#46686111) Journal

          Overall, high-speed recharge for cars may bring as many or more problems than it solves, especially when the battery-swap alternative allows for load-leveling, for leveraging the ability to purchase at the cheapest or most environmentally friendly times, for eliminating the need for an owner to worry about large battery-replacement costs and potentially even for returning power to the utilities at peak-demand times.

          Oh no. Battery swapping carries the greatest number of problems of all electric car charging solutions. It means all cars need to have a standardized battery size, technology, and connector, and even a standardized bay if you want to load them in any hurry. This will slow EV development from a sprint to a crawl as every car will now carry legacy technology that will have to be accounted for.

          This will also have big ramifications in car design. Right now, most cars have a bespoke gas tank for their sub-model (a great example I've learned about the hard way is the AE90-series Corolla. 2-door, 4-door, and wagon tanks are different. Carbed and EFI tanks are different. And then there are two EFI tank variants with different ports on top just to make things interesting. So you're looking at 6+ different tanks for a line of cars that would seem to be mostly very similar). Same thing with EVs and battery pack designs. Lots of space will be needed to shoehorn standardized batteries into the cars with a nice accessible swapping bay.

          And then after you've gone and kneecapped EV development and made every car look like it's smuggling a bulk-pack of cigarettes through an airport, you might one day receive a dud old battery and get stranded on the side of the road anyway, because each battery will have a unique operating history you don't know about. Mission accomplished!

      • I'm not sure you really need 1-2 minute charging.

        Assuming an all electric infrastructure.

        Cars would start the day fully charged - no need to "fill up" on the way to work - because of an overnight charge and it's reasonable to assume that will be sufficient for a typical day for most people.

        The remaining obstacle is long distance driving. A 30 minute charge time every 4-6 hours wouldn't be unreasonable but that would only work if there wasn't a queue before you got to start charging. That's going to mean a l

      • Very fast charge (on the order of 1-2 mins for current battery sizes) would make "gas stations" viable for electric cars.

        I think the magic tipping point number is probably somewhere around 10-15 minutes. Maybe 20 at the outside. I doesn't have to be shorter than gasoline pumps but it needs to be relatively close in duration to get enough juice to go something like 200 miles or thereabouts. Technically challenging but based on observed technology progression I think it will happen before terribly long - perhaps 10 years.

        • I don't know - if you're talking 4-6 hours of driving on a charge then you probably want to stop and eat and use the facilities more often than you need to charge the car. How long will you be busy? There's your optimal charging window.

    • by swb ( 14022 )

      I would imagine mass is probably the biggest variable. What's the increase in range for every reduction of 1 kg of battery, presuming the power side stays the same?

      • Actually, drag is the most important issue on long trips. Mass is less of an issue in EVs because you can recapture 60% of your kinetic energy when you brake, and mostly a non-issue when driving at a constant speed on the highway. Adding lithium batteries to a car without increasing the drag profile invariably increases the range.
    • Long charging times for electric vehicles stop any journey where the trip is greater than the battery range. Who wants to have to stop for hours to get a full battery when you are trying to get somewhere.

      Liquid fuels can refuel most vehicles in 10 minutes, and half of that time is queuing and paying. Electric vehicles will have match that capability at some point or they are going to be forever stuck in the niche of toys and glorified shopping carts.

      • Long charging times for electric vehicles stop any journey where the trip is greater than the battery range.

        Yes they do, but we don't need this tech to fix it. Existing batteries can do it just fine [wired.com], if we would only invest in enough high power charging points.

      • Electric vehicles will have match that capability at some point or they are going to be forever stuck in the niche of toys and glorified shopping carts.

        They probably don't need to match the speed of refueling with gasoline but they need to get close. I figure something in the 10-20 minute range for around 200 miles of range is probably about where it will get competitive.

        There is the option of having a towable generator for longer trips to extend range for long trips. Think of it as hybrid on demand. Not the most elegant of solutions but might be a useful stopgap measure while electric vehicle charging tech develops.

        • by Guspaz ( 556486 )

          They're not that far off now. Your goal is 20 minutes for 200 miles of range, Tesla is doing ~110 miles in that amount of time. They've said that they might eke a little bit more out of it the current cars and chargers (they do 120 kW today, and are planning to move to 135), which would get them up to ~130 miles per 20 minutes), but that future bumps will require improvements to the hardware itself.

      • That depends heavily on your driving style. If you can drive for 4-6 hours on a charge then most people will probably want to stop for food/restrooms more often than they need to for recharging. As long as you can recharge in less time than it takes you to eat and use the facilities it'll be a non-issue for most people. Of course it'll undermine the "gas up and grab some fast-food to eat on the road" behavior, but frankly that's probably a good thing for most people's stress and health levels, I imagine

    • Actually it is VERY important. If your battery takes 4 hours to charge, it effectively limits your range for long road trips and also pretty much prevents short road trips.

      If it takes an hour to recharge a battery, you can stop for lunch, recharge, travel till dinner, then stop again, travel on to your motel, then sleep for the night. Repeat.

      If it takes four hours, then you ride in the morning, run out of power, stop for half the day, eat lunch, then are forced to wait 3 hour while you finish rechargin

      • Existing batteries can charge to 80% in half an hour. The only thing stopping us is the scarcity of high-power charging stations, and making batteries charge faster only makes those stations more expensive and less likely to be actually installed. That is why improving battery capacity and efficiency, not the charge rate, and rolling out more infrastructure using the existing standards are the most important things for EVs right now.

    • People are much more willing to put up with a 200 mile range on a car if it only takes them a 2-minute stop to recharge. If it takes an overnight charge, then that's a deal-breaker for anyone who might want to make long trips.
      • There's a pretty big continuum between 2 minutes and overnight. Existing EV batteries can charge in half an hour at a suitable fast-charger station with a manageable cable assembly. Making them charge faster simply doesn't help because it (a) does not solve the problem of needing expensive high-power chargers everywhere, and (b) creates a new problem because you need ridiculously high voltage and/or current capacity in all the charging cables.
    • by Adriax ( 746043 )

      Charging is the current hangup for electric cars. Mainstream is addicted to the ability to drive any distance they want with one vehicle and be able to refuel in 10 minutes at any gas station of their choosing.

      Give someone an electric car with a 1000 mile range and they'll complain about having to stop for 8 hours to recharge it in the middle of their 2000 mile roadtrip they totally plan on taking one day. Having to stop for 8 hours to rest after 16 hours of activity is totally unacceptable from a car.

      • ^Get to a 1000 mile range for an 8 hour charge with a reasonable price point and you'll see mass market adoption because there are a large number of drivers who rarely drive that far. Folks that buy those cars won't complain.

        Seems that we have a unnecessary complaint about future complainers.
        • Yeah. And as an added bonus it will get those people driving non-stop for 25 hours (2000 miles/80 mph) off the road, making everyone safer.

          Okay, yeah, a lot of folks may be driving in shifts, but I've known plenty that don't think twice about saturating their system with caffeine and doing it solo. I tried that once, when the hallucinations (sparkles + flashes) started up around hour 18 I decided it was time to get off the road and get some sleep.

      • Since the TSA started their nonsense, I take at least one 2000 mile trip and multiple 700+ mile trips per year. Living in Dallas, I can get to San Diego, Orlando, or New York in roughly 24 hours or less with two drivers, switching out at each fuel up.

        I'd love to have a Model S for the 70% of my mileage to and from work, groceries, and entertainment, but 30% of my driving, I'd still have to have internal combustion.
        • >but 30% of my driving, I'd still have to have internal combustion.

          Of course that doesn't necessarily require a different vehicle - add a generator insert for the trunk, or a small trailer, and you're good to go. Better yet use a fuel cell and easily double your mpg over a traditional car.

    • Battery weight, size, capacity, and charging time are all important attributes for electric cars in general. R&D is being done to address all of those things, with varying success. You are correct in noting that even if a battery is capable of recharging in minutes, delivering that much power safely in the real world has some major hurdles. Other replies have mentioned battery swapping as one workaround. Another workaround that I'm hopeful for is batteries full of electrically charged liquid slurry.

  • by mpoulton ( 689851 ) on Monday April 07, 2014 @11:00AM (#46684533)
    A Tesla S has an 85kWh battery. To charge that in 30 seconds requires 10,200,000 watts of power - approximately the full electrical service to a decent size skyscraper. That's 42,500 amps at 240V, the full maximum power available to over 212 modern homes and a totally impractical amount of current to handle with any reasonable electrical equipment. So while fast-charging batteries are great and a necessary step forward in technology, the universal adoption of electric cars will require not just upgrading our infrastructure, but a complete rethinking and redevelopment of the electrical grid using not-yet-imagined technologies.
    • Once electric cars become prevalent, the charging time doesn't really matter for the supply and HV distribution side of the grid - each car sucks either 10.2MW for 30s or 10.2kW for a bit over eight hours (30,000s). Once there are enough that the spikes in charging smooth out, the demand increase is the same whichever charging rate you use. The only problem really comes at the edge of the grid, with the connection to individual houses currently being sized about three orders of magnitude wrong for this us

      • You don't want to know how much that upgrade will cost.

        If rapid charging ever becomes viable, they will have a second battery pack in the garage to supply the rapid charge power. Otherwise you'll need high voltage/current service to every garage.

        There is not much need for home rapid charging. This is more about highway travel. If you've got 8 hours to charge, it will almost certainly be easier on the batteries to charge slow.

    • IANAEE (I am not an Electrical Engineer), but couldn't you just locate some capacitors close to the charging location? Charge them up slowly over time, then quickly discharge them when a car needs juice, that way you're not putting the load on the grid all at once. It probably wouldn't work if you were to set them up like gas/petrol stations, since you wouldn't have much time between discharges to recharge the capacitors, but for home use, it seems (to someone such as myself who knows next to nothing on the

      • It would still work (capacitors/batteries) in the sense that it would smooth the grid loading - you would charge during low times so that you could service at high times.

        Of course, that requires enough storage for buffering - which would be probably 50-60% of the total capacity charged in a day. Well, that and cables too big to handle - even at 400V, you're still talking thousands of amps - and cable diameters measured in inches.

      • IANAEE (I am not an Electrical Engineer), but couldn't you just locate some capacitors close to the charging location? Charge them up slowly over time, then quickly discharge them when a car needs juice, that way you're not putting the load on the grid all at once.

        There's usually a queue at my local gas station.

        • IANAEE (I am not an Electrical Engineer), but couldn't you just locate some capacitors close to the charging location? Charge them up slowly over time, then quickly discharge them when a car needs juice, that way you're not putting the load on the grid all at once.

          There's usually a queue at my local gas station.

          If you had quoted just one more sentence, you'd have seen that I said it wouldn't work for gas stations.

        • So put a big, obvious indicator on the charging station that shows a color-coded load level. After a while, EV owners will come to understand it at least enough to know that a high reading means their car will charge slower.

          If consumers can figure out those little pinch-the-ends-to-read charge indicators in some batteries, and what a regular traffic signal means at an intersection, they can figure out "green means fast, red means slow" at the charge station and charge up or go elsewhere accordingly.

          Station

        • by Guspaz ( 556486 )

          Even with a queue, an individual gas hose isn't in use 100% of the time. There's the time you take to pull up, get out of your car, connect the hose, disconnect the hose, pay, and drive off. Even if capacitors supported a 1 minute charge every 3 minutes, that'd probably be enough.

          Personally, I think a 30 second or 1 minute target is unnecessary. It takes longer than that to refuel a regular car anyhow. Five or ten minutes is probably fine, and charging 85 kWh in 10 minutes can be done with ~500 kW. That's h

    • A Tesla S has an 85kWh battery. To charge that in 30 seconds requires 10,200,000 watts of power - approximately the full electrical service to a decent size skyscraper. That's 42,500 amps at 240V, the full maximum power available to over 212 modern homes and a totally impractical amount of current to handle with any reasonable electrical equipment. So while fast-charging batteries are great and a necessary step forward in technology, the universal adoption of electric cars will require not just upgrading ou

      • by Guspaz ( 556486 )

        Tesla's plan is to have large amounts of grid storage on-site, powered mostly by solar (by building roofs over the charge stations). Tesla claims that they should be a net-positive in terms of grid power (that they produce more power than they consume). I'm skeptical that would work once they get popular, but it does still offset a chunk of the power draw, and the grid storage on-site smooths out the surges in demand.

    • by LoRdTAW ( 99712 )

      The gas stations would have to have their own substations and high voltage service to do 30 second electric car charges. And a typical gas station has about 8 pumps. So 80MW to charge 8 cars in 30 seconds is going to be a killer unless you run a 120kV ~400A service to the gas station. Overhead lines would be a no go in many areas and underground lines are super expensive to lay. All that for a gas station.

      A single 10.2 MW "pump" would require 430A @ 13.8kV. Or run 69kV to the pump and have an 86A circuit.

      A

      • by Guspaz ( 556486 )

        Power cables typically use stranded conductors specifically to avoid this problem. Drop your time requirement to five minutes (half a megawatt) and use the kind of power conductors that normal people use and you've got something practical.

        Current charge stations (with their existing cabling) are expected to be able to do up to 150 kW. Worst case, you use two charge cables per car, and going from 150 kW to 250 kW is suddenly not such a big leap.

    • by eth1 ( 94901 )

      A Tesla S has an 85kWh battery. To charge that in 30 seconds requires 10,200,000 watts of power - approximately the full electrical service to a decent size skyscraper. That's 42,500 amps at 240V, the full maximum power available to over 212 modern homes and a totally impractical amount of current to handle with any reasonable electrical equipment. So while fast-charging batteries are great and a necessary step forward in technology, the universal adoption of electric cars will require not just upgrading our infrastructure, but a complete rethinking and redevelopment of the electrical grid using not-yet-imagined technologies.

      It could also be a grid engineer's best friend. You just have to change the way you think about it - the cars would be a *massive* local storage resource. The VAST majority of people are just going to be plugging their cars in overnight at home, and starting with a full "tank" every morning. I could imagine a system where, once electric cars are ubiquitous, most parking lots and cars would be designed so that when you park, your car just automatically gets hooked into the local grid. You set some parameters

    • by gatzke ( 2977 )

      I am not a EE, but a 10 MW generator is not physically that large. I have seen giant flywheels that store a lot of energy and are spun up by a smaller motor on the other end running continuously (TUM / IPP fusion reactor energy storage near Munich). You could imagine putting something like that in to avoid fouling the power grid with 30 second 10 MW spikes.

      I think the problem is letting a human connect these things. Maybe if you automate all the connections, similar to the Tesla battery swap stations? T

  • by kheldan ( 1460303 ) on Monday April 07, 2014 @11:01AM (#46684543) Journal
    At 2.5W, you won't be charging this battery in mere seconds with a standard USB connection. Anyone else notice the rather large connector the demonstrator plugged in to charge it? You'd have to have a charger capable of supplying several amps to charge it that fast. Assuming it's a 3.6V nominal battery at 2000mAh, that's 7.2WH. For a typical 2.5W USB connection, you'd still take 2.88 hours to charge your phone (longer if you take inefficiencies into account). Also, can a mini- or micro-USB connector's power pins handle several amps without getting burned? Don't get me wrong, I'm not discounting the possibilities of this development, but I am saying the demonstration was a bit misleading, and that there are problems that would have to be worked out before it'd be practical for a phone battery.
    • that there are problems that would have to be worked out before it'd be practical for a phone battery.

      Or we could separate power from data and do away with "all approx. 5V connections must use a USB adapter." Bonus, it solves the charging station hacks.

  • by PvtVoid ( 1252388 ) on Monday April 07, 2014 @11:01AM (#46684547)
    ... discharge time is another. How long does the battery last? TFA (typically for stupid tech articles) omits this detail.
    • by kheldan ( 1460303 ) on Monday April 07, 2014 @11:05AM (#46684607) Journal
      Actually, it doesn't omit that at all, it states their prototype is 2000mAh. For discharge time, you'd have to know what the power requirements are for the phone they used to demonstrate it, and probably what the discharge curve for the battery looks like.
      • Actually, it doesn't omit that at all, it states their prototype is 2000mAh.

        I stand corrected. Thank you!

    • Only not explicitly explained.

      In short - it lasts the same as the battery of that capacity lasts today.

      'In essence, we have developed a new generation of electrodes with new materials â" we call it MFE â" Multi Function Electrode," StoreDot CEO Doron Myersdorf told Gizmag. "On one side it acts like a supercapacitor (with very fast charging), and on the other is like a lithium electrode (with slow discharge). The electrolyte is modified with our nanodots in order to make the multifunction electrode more effective."

      It's basically a supercapacitor on top of a battery.
      You charge the capacitor quickly, it discharges into the battery slowly, and because the capacitor is actually a part of the electrode the loss is minimal.

      On top of that, not having to discharge the capacitor into the battery all at once, it can discharge into the battery slowly, without heating it up, increasing the battery's life-cycle.

      Discharge time is

  • Let's see, a 4,700mAh 5V battery has a capacity of 23.5 VAh or 84.6kJ. To charge that in 30s, you'll need a 2.82kW charger output. So whether it's feasible or not probably depends on what jurisdiction you're in - a British 240V 13A socket will give you 3.12kW, so as long as your losses are below 10% you'll just get it. An Australian 240V 10A socket will give you 2.4kW, so allowing for 90% efficiency of the charger you'll get about 40s to charge. A US 110V 15A socket will give you 1.65kW, requiring about

  • If a 2000 ma/hr (2 amp/hr) battery supplies 2 amps for a full hour then we need to put the same amount of current in reverse to fully charge it. So a 2 amp charger can charge a (dead) 2A/hr battery in 1 hour. To do it in 30 seconds we need a heck of a lot more current. So a little math reveals that to charge it in a minute we would need 2A*60min = 120A/min charge current. And for 30 seconds we would need 240 Amps. Though I bet most people won't be charging stone dead batteries.

    30 amps could charge a dead ba

    • You're not looking at it correctly. You have to consider voltage to get a picture of actual power contained in the device. 2ah * 5v = 10 Wh = 0.01 kWh. For convenience, we look at this in kilowatt*seconds = 36kWs. To charge in 30 seconds would therefore require an absolute minimum of 36kWs/30s = 1.2kW of power. Even with some line losses this will fall well within the output capabilities of a U.S. standard residential plug.
  • by robot256 ( 1635039 ) on Monday April 07, 2014 @11:09AM (#46684659)

    Am I the only one skeptical of whether this is real or not? What they describe doesn't make a lot of sense to me:

    On one side it acts like a supercapacitor (with very fast charging), and on the other is like a lithium electrode (with slow discharge). The electrolyte is modified with our nanodots in order to make the multifunction electrode more effective.

    So is it a battery or a capacitor? Maybe I'm just woefully ignorant of how lithium batteries work, but I was under the impression that it was the surface area of the electrodes and the activity of the electrolyte that govern the internal resistance, and hence the charge rate. Capacitance has nothing to do with it, unless you are charging up a capacitive "buffer" that drains into the chemical battery more slowly afterward, but that seems kind of pointless.

    Pulling out buzzwords like "environmentally friendly" materials and nanodot "self-assembly" doesn't really help your plausibility, either. Anybody can make a box with banana jacks and an app with a timer in it.

    • It's called pseudocapacitance: basically you have a hybrid of a battery and a capacitor, aiming for the high power density (i.e. rate) of the latter and the high energy density of the former.

  • Comment removed based on user account deletion
  • If we wanted to solve the charging fast problem, couldn't we just make battery swapping easy in phones? You'd leave a battery on the charger and when you get home, you swap the batteries in like 5-10 seconds.

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