Scale that to a 'leccy car
and you have a winner.
Three researchers have come up with a technique they claim will allow laptop and smartphone batteries to be recharged in two minutes. Huigang Zhang, Xindi Yu and Paul Braun of the University of Illinois created a new battery cathode - the negatively charged one - formed "from a self-assembled three-dimensional bicontinuous …
How easy would it be to increase the capacity of the batteries to the point where they would be useable in EVs?
The biggest stepping stone with vehicles seems to be the amount of time it takes to charge vs filling a liquid fuel tank. if these batteries charge to 90% in a couple of minutes, take that to EV level and you'd be able to fully charge your car while parked up for an hour doing the shopping...
While this super fast charging might work on small scale batteries it could get a bit tricky when you start getting into the massive batteries used in electric vehicles. To "fill" a battery for an electric vihicle in a time comparable to filling a gas tank would likely require that the electricity be flowing at thousands of amps.
"Nickel Hydrogen cells don't tend to explode; they mearly vent hydrogen gas at ~200°C. Of course if you light it when it comes out, that is your own problem."
I think you'll find Hydrogen at +200c venting into the air on Earth won't *need* an ignition source.
Should make a really nice "afterburner" effect to add to you EV though.
while I agree that this would be dangerous if just left to a simple twin+earth plug, with proper safety precautions kept in mind I don't see how this is any worse than we do now.
Perhaps a locking mechanism which won't allow the "pump" to be powered on until the plug is locked in place, and won't allow the plug to be removed until the pump is powered down again, similar to the Gas pumps used for LPG, at no point will anyone be at risk from electrocution.
Alternatively the batteries could be charged in parrallel. Instead of a single cable charging at thousands of amps, several cables could be used each charging at hundreds of amps. The more cables, the less amperage required down each one.
It's no worse than a hose-ful of highly flammable liquid/gas - if done well it could even be safer!
I'm sure someone more intelligent than I will work out a way of making money putting this tech into cars!
High current line, batteries in parallel when charging. Could charge each cell at the same time and be done in a few minutes.
The Tesla uses the equivalent of laptop batteries (http://en.wikipedia.org/wiki/Tesla_Roadster#Battery_system) so connecting the sheets in parallel when charging should do the trick. You wouldn't want to stick your tongue on the end of the charging socket though....
What I don't understand, if the charge time is such an issue with EVs, is why car manufacturers don't build cars with removable rechargeable batteries. Get the the petrol(?) station, remove your battery and swap it for a fully charged one, and drive off. Your previous battery gets recharged gradually after your gone and sold to another driver the next day.
I assume manufacturers must have thought about this (it's an obvious idea) so what are the pitfalls? I realise petrol stations would have to factor in the cost of taking batteries out of circulation once they've reached the end of their life and might need some mechanical apparatus to aid removal, lifting and reinsertion of batteries due to their weight but I can't think of any show stoppers.
Anyone know why this hasn't been tried?
actually battery recharge time is only the obvious immediate problem, using hydrogen for power storage is one way to get around that problem (as well as the problem that there aren't the resources to build the batteries that would be required, but at the cost of reduced efficiency)
the real problem is you still need to produce (and distribute) the huge amounts of electricity that would be needed in the first place - a few thousand demo cars isn't the same as placing our entire transport demands on the national grid, we don't have the ability to produce anywhere near enough electricity for that, and afaik there aren't any plans to change that
The big problem being, just how green would it be if they tried to scale production to the level required to make electric cars viable.
Much of the materials used in making electric vehicles are extremel complex to extract, and not by particulary environmentally friendly processes. Until we solve this secondary problem, electric vehicles will remain a novelty item.
I'm not knocking the EV - just pointing out it isn't as simple as solving the charge time
Yes, that is true what you say however:
The cable to carry all that power whould be rather huge. Also the power drawn would be so much that Sainsbury's would need their own power-station to power all of their charging stations. Of course with that power station not doing anything when you weren't there charging, the cost of the electricity would be pretty high (You can't just bung 100MW onto the grid randomly depending on how many cars are charging)
A much better idea would be for you to plug in your car when it is not running (probably 20 hours a day) and charge it slowly. The added bonus is that you don't stress the power supply network, the charging electronics or the battery, so they can all be cheaper and last longer. Oh, and the charger would be a HELL of a lot cheaper to make too!
Of course for taxis and buses it's a different situation, and there the best current option is a system where the empty battery is switched out and changed for a charged one.
Re: Dr Insanity:
A decent EV battery is 50-100 KWh in capacity. In order to charge that in 5 minutes (comparable to filling with petrol) you need to push between 600KW and 1.2MW into the car. Unless you have a very high voltage (and the associated problems that that brings) this will need a lot of current.
EV users charge their cars every night, so only need to charge away from home if doing a daily journey in excess of the car's range. The comparison with filling a legacy car with liquid fuel isn't really valid.
...but any word on the energy storage density per unit volume and/or mass? In other words, can they make one that fits into the back of my HTC and lasts more than 16h, or one that can store enough energy to propel a car a few hundred miles without adding several tons to the mass?
...the old "self-assembled three-dimensional bicontinuous nanoarchitecture consisting of an electrolytically active material sandwiched between rapid ion and electron transport pathways" trick!
I always knew that would work. Honest. I told my mate Derek about that down the pub, you can ask him yourself! Or was that my auto-inflating glow-in-the-dark Bulgarian airbag idea? One or the other...
...so I've read.
Me thinks there will be a market for 'small' (LOL, ~300MW) nuclear plants to be buried beneath the stations' forecourts. Not to mention superconducting cables, plugs and sockets.
Also, someone may wish to compute V=IR, P=V*I, T~P, and PV=nRT.
I was wondering what to do with some self-assembled three-dimensional bicontinuous nanoarchitectures consisting of an electrolytically active material sandwiched between rapid ion and electron transport pathways just the other day!
This is actually dead cool and if its charge cycle life can be increased and the battery can be scaled for EV tech, then we have a serious breakthrough.
Ok, 'C' in this context doesn't appear to mean coulombs. Having now read the article, the following is the relevant phrase:
"the C-rate−1 is the time in hours required to fully charge or discharge an electrode or battery; an nC-rate indicates that the current chosen will discharge the system in 1/n h"
The percentages quoted is the capacity of the battery at a higher charge/discharge rate as a proportion of the 1C rate.
This explains most of it:
"At 305C, the NiOOH cathode delivers 90% of its 1C capacity, and when the discharge rate increases to the unprecedented value of 1,017C (291 A g−1), the electrode delivers 75% of its 1C capacity in ~2.7 s. In comparison, commercial NiMH cathodes, which consist of a large-pore-size (~50 µm to 1 mm) nickel foam coated with a thick layer of NiOOH, usually retain ~1–2% of their capacity at C-rates exceeding 35C"
"In any case, today's batteries lose capacity over time. So does the trio's battery, but they found it to maintain its capacity for at least 100 charge/discharge cycles." - at least a hundred? If this is more expensive than your standard rechargeable battery - and it will be, even just looking at materials - you're going to b spending a lot of money on replacing it. If an EV is getting a charge every night, you'll be replacing your batteries twice a year, just to keep that full charge. Ouch.
Awesome tech, but it needs work before it's mainstream. Let's try for 100 *thousand* cycles, shall we?
You going to need a BRICK of a PSU.
14V 4000mAH approx = 1hr @ 56W (about 90% of a 4400mAH pack), and er, 4 amps
same charge in 20 seconds is 180x, = 10kW! at 720A on the 14VDC, (about 45A, or more than three plug sockets!)
So ... maybe very small phone batteries. But not big laptop packs.
Do I smell burning motherboard?
I am inclined to agree with previous posters. If this could scale to run electric vehicles, even if the range wasn't up to much, if it only took 10-15 minutes to recharge, you'd be on to a winner.
Even a half hour break every 200 miles would be acceptable in my books for a full charge, allowing shorter stops to deliver less charge as demonstrated, 5 minutes for a quarter of a tank maybe?
Scaled up to EV sized batteries this would be a step change and with re-charging points as common as filling stations (in principle *more* common given its basically a socket + metering and billing hardware) and people *could* become quite comfortable with EV's.
Ironically the question might be now can it be built to discharge *slowly* enough not to fry the motors.
Obviously this is a *long* way from production and is certainly not the first battery tech that looked incredible in the lab but has not set the world on fire (unlike some of the successful ones, which on occasion have).
Thumbs up and I will wish them *every* success but this is just the start of the end of the beginning. IE about v0.1.
But if they make it to 1.0 I'll be cheering.
Use an array of the new batteries at the charging station to dump the power into the new batteries in the cars. The station batteries can charge relatively slowly using the existing grid, spreading the current draw across many hours, while still providing the ability to charge a car in a short period of time.
Battery chargers with built-in thermionic diode based coolers.
Peltiers it seems are very inefficient but using these in combination with silicone thermal pads increases the efficiency of the charging process as well as the longevity of the cells.
Result is that the cells last 2000 cycles with no capacity loss.
It also occurs to me that making each cell with a void in the centre where liquid coolant flows and polarised hollow magnetic contacts at each end could also allow a higher capacity cell which would be compatible with conventional chargers and allow for rapid assembly of custom packs with the ease of Lego.
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