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Nanostructured Li-ion Batteries for Electric Cars

schliz writes "Researchers at the Delft University of Technology are developing nanostructured batteries that are expected to deliver more usage between charges, and shorter charge/discharge times, to mobile consumers within the next five years. The batteries will improve electric and hybrid vehicles, researchers say."

3 of 153 comments (clear)

  1. it's explosively fast by User+956 · · Score: 5, Funny

    batteries that are expected to deliver more usage between charges, and shorter charge/discharge times

    I believe Sony has perfected the battery with the absolute fastest discharge time. I don't see how this can compete.

    --
    The theory of relativity doesn't work right in Arkansas.
  2. Re:What's wrong with... by Anonymous Coward · · Score: 5, Informative

    Lead-acid batteries are a lot worse in comparison...

    Lead-acid batteries
    Energy/weight 30-40 Wh/kg
    Energy/size 60-75 Wh/L
    Power/weight 180 W/kg
    Charge/discharge efficiency 70%-92%
    Energy/consumer-price 7(sld)-18(fld) Wh/US$ [1]
    Self-discharge rate 3%-20%/month [2]
    Time durability 6 months
    Cycle durability 500-800 cycles
    Nominal Cell Voltage 2.0 V

    Lithium-ion batteries
    Energy/weight 160 Wh/kg
    Energy/size 270 Wh/L
    Power/weight 1800 W/kg
    Charge/discharge efficiency 99.9%[1]
    Energy/consumer-price 2.8 Wh/US$
    Self-discharge rate 5%-10%/month
    Time durability (24-36) months
    Cycle durability 1200 cycles
    Nominal Cell Voltage 3.6 V

  3. Re:The first of many stories by fyngyrz · · Score: 5, Informative
    They [ultracaps] certainly don't have the energy density of batteries

    Actually, they're getting very close, and right now, there are projects projecting power densities three orders of magnitude higher than batteries, in the 100 KW/kg range. So I don't think the current state of affairs (batteries > ultracaps) is going to obtain for very much longer.

    and the largest problem with them is that the discharge from an ultra-capacitor is hard to deal with using normal electronics. It can be compensated for, but it isn't easy.

    What? ultracaps have the same discharge curve as any capacitor does; the voltage drops very smoothly as the energy in the cap is dispensed. "Dealing with it" is nothing tricky at all, the technology has been in place for this for literally decades. Modern switching power supplies are *very* efficient at creating constant voltage outputs from all manner of raggedy inputs across a wide range of input voltages, if and when required. They can be engineered to be reliable and very long lasting. This is simply a non-problem. Also, ultracaps can absorb energy (for example, from regenerative braking) at a much higher rate, leading to less wasted energy. We have all manner of high-current switching devices with such low on-resistances these days as to be utterly amazing to an old-timer like me.

    I also don't buy the "environmentally friendly" nature of them as well. While they may be better than NiCd batteries or the more traditional Lead-H2SO4 batteries in terms of what they will do to the environment, you can't call them a perfect solution either. The metals used in the construction of these types of capacitors have their own kind of impact on the environment just like any manufactured product.

    You're just hand-waving here. Recycling is one issue, toxicity is another, corrosion is another, and all of them are far less critical for ultracaps - not to mention that the lifetime of an ultracap is so much longer (up to a quarter of a milling charge/discharge cycles, or more) than that of a battery, so it is that much more seldom that recycling becomes an issue. It really isn't reasonable to say that ultracaps pose the same kind of environmental issues that batteries do. They don't. Perfect? No. But what is?

    If a "Moore's Law" were to apply to battery capacity, instead of the (presumed) 18 month half-life of procesor density and speed, it will be more like 15-20 years instead for improved energy density.

    Yes, but (a) ultracaps aren't batteries at all, and (b) ultracaps are increasing in capacity at a prodigious rate, where batteries are not. Mind you, they're coming from behind, but they're a brand new technology with tons of new research driving the improvements, while batteries are not new and many, many avenues have been tried and abandoned for increasing battery capacity for exactly the reason you cite: It is hard to improve the current battery designs.

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