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News Silicon to improve batteries tenfold

Discussion in 'Article Discussion' started by Claave, 16 Nov 2011.

  1. yassarikhan786

    yassarikhan786 Ultramodder(Not)

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  2. Bakes

    Bakes What's a Dremel?

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    The issue with fast (dis-)charging is that it kills the battery far, far quicker - so you frequently have to replace the battery. That's why electric car manufacturers tend to build in checkers to see how fast you've been charging the battery, to protect against spurious warranty claims.


    If you manage to get 400 miles off a charge with a 30 minute break in between, that'd be fine - most drivers would take a 30 minute break by that point (and if they didn't, they'd likely be in an unsafe situation).
     
  3. yassarikhan786

    yassarikhan786 Ultramodder(Not)

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    Yeh, that would be awesome. But right now it is just a concept/idea, so I wouldn't get my hopes up.
     
  4. elthusiast

    elthusiast What's a Dremel?

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    Argh

    I get so sad when I see this. Are you really so incapable of being just slightly sceptical or so uninterested that you don't actually try to LISTEN first? That would prevent asking stupid questions that only betray your own ignorance.

    There are many reasons why electric vehicles are better for the environment. The most fundamental is simply that electric motors are far more efficient than combustion engines. The most efficient internal combustion engines out there spend 75% of the chemical energy released when burning the fuel to heat the engine, the radiator, and the exhaust system.

    In addition, fossil-tech engines exhibit a quite narrow band in which the engine can output anywhere near maximum power and torque. This is why the cars have multiple-speed gearboxes, which means further mechanical losses (heating the transmission) and more parts that wear out (not a big factor in the environmental respect, but a small one).

    Another major reason is of course the fact that electric cars produce no tail-pipe emissions and much less noise than fossil-tech cars, both of which have a major impact on our human environment in cities. The WHO has warned about the now well-established link between NOx and lung cancer, a problem that has become much more serious in Europe as the car park has shifted to more and more diesel vehicles. In Norway, the government has already announced that it will introduce restrictions on diesel cars when pollution levels run too high in cities, meaning that it will be illegal to drive a diesel car during those periods. (Local pollution level depends mainly on how much traffic there is to emit it, and wind to disperse it.)

    Even if you ran your EV exclusively on power from coal stations, and even if your EV was a big, heavy, luxurious vehicle like Tesla's Model S, your driving would cause considerably less emissions than if you drove a Golf BlueLine diesel (the most fuel efficient internal-combustion engine in the world). And of course no tailpipe emissions wherever you drove.

    To get a handle on how energy efficient EVs are, I recommend the following exercise: Head to Wikipedia. Look up Tesla Model S and find out what the largest battery pack capacity is, and the range you can expect with that. Then look up the energy density of gasoline and diesel, and convert the Tesla battery pack to the equivalent "tank volume" (i.e. storing the same amount of energy).

    Since I am aware that most people are too lazy to ever try to look up actual numbers for anything (even though they do enjoy pretending that they want to know stuff!), I am going to provide the answers here: The largest battery pack you can get for the S is 85 kWh, and gives you a range of up to 300 miles (though the EPA2 rating is lower, as more of the miles are stop-and-go city driving - which reduces range the same for EVs and other cars). The energy density of gasoline and diesel is a little over 10 kWh per liter. In other words, the Tesla takes you 300 miles on a battery storing as much energy as just over 2 gallons of gasoline or diesel. (The energy density of diesel is slightly higher than that of gasoline, but not enough that it's worth bothering with when comparing such completely different beasts as fossil-tech cars and electric cars.)

    Now, I've said that an EV is better for us even if we run it on coal. But, even more important: An EV means your car is able to run on any energy source. Electricity is not found in nature (well, we don't find it in practically exploitable forms anyway) but can be generated from pretty much any source (though with varying degrees of efficiency and at very different costs). This means that running EVs is a shift from reliance on fossil fuels to a reliance on energy. There is no shortage of challenges to produce enough energy in the future, in a safe, sustainable, cheap and reliable way, but EVs help both by being much more energy efficient, and by being completely agnostic about the actual power source. If we find better ways to make electricity in the future (and much is underway) EVs are ready for them. While we do continue to find new ways of extracting more fossilized energy, nobody that knows anything about it could look you in the eye and say they are "better ways": "ever more intrusive, ever more expensive" is rather closer to the mark.

    Finally, an important point that is too seldom mentioned: Renewable energy sources tend to be intermittent; the wind comes and goes, waves are sometimes huge and sometimes not, the sun is strong or the cloud-cover thick, and so on. In order to rely on renewable energy it is paramount to be able to store huge quantities of energy. (As it is, we constantly monitor and adjust production to match consumption at all times.) Several possible solutions to this problem have been proposed, for instance to pump water up into reservoirs during times of excess (e.g. when the sun is strong and the wind blows fast) and use traditional hydropower to make electricity in times of starvation. But, given batteries that have the capacity people need and then some, an electric car park with smart chargers could provide a very cost-efficient and capacitious energy store. Our cars could charge up when there's excess power and put energy back on the grid (in fact, selling it!) when there is too little, while making sure to have enough power to meet our needs. Batteries aren't currently good enough to allow this, but there is good reason to expect batteries to improve quite dramatically. The Obama administration has devoted a few hundred million dollars to research in this field (which, if it leads to any significant gain at all is really peanuts, about a tenth of what it costs to make a movie!) with the stated goal of halving the cost per kWh (from 3,600$ to 1,800$) by 2014. McKinsey, by the way, estimates that electric cars become cost-competitive (total cost of ownership) with traditional cars at a cost level of about $2,500 per kWh. In other words, if batteries improve nearly as much as we can reasonably hope, electric cars will fairly soon be much cheaper to own as well as far more pleasant and far more environmentally friendly.

    This is running far too long, but lastly I'll just encourage people to consider what else might change if your car has all its energy reserves available in electronic form and without a motor running. Tesla and several others have already implemented a few of the more obvious ideas, such as being able to use your phone to tell the car to heat up the coupé and be nice and comfortable by some preset time. Where I live there are many days every winter with 20 below freezing, and I can vividly imagine arriving at my cosy space-age car while my neighbour is trying to get the ice and snow off the front window some particularly cold morning... :naughty:

    Sorry about the length. But I care passionately about electric cars and hope I don't write so boringly that none of it can rub off to someone who reads this.
     
    Wicked_Sludge likes this.
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