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Power Technology

Simple Chemical Trick To Boost Battery Efficiency 149

space_mongoose writes "Hitachi thinks that a simple chemical additive could significantly improve battery life. Alkaline batteries have a positive electrode of manganese oxide and a negative electrode of finely powdered zinc, but zinc oxide forms around these grains of zinc. Hitachi's solution is to replace the zinc with a fine powder of zinc-aluminum alloy, displacing the zinc within the zinc oxide layer making it a much better conductor."
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Simple Chemical Trick To Boost Battery Efficiency

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  • Costs? (Score:4, Informative)

    by bigberk ( 547360 ) <bigberk@users.pc9.org> on Thursday May 17, 2007 @01:04AM (#19156835)
    I didn't see any mention of cost in the article. For instance looking at market aluminum prices, I am astounded to see that the price of the raw metal is increasing something like +23% per year. I don't know if relatively speaking the aluminum/zinc oxide is more costly than just zinc, but I think a greater point is... if the raw material costs are increasing at such a rapid pace (over 20% per year!) then just how "cost effective" will these batteries be in the long term?

    P.S. the skyrocketing metal costs, including important ones like copper and silver, are part of an ongoing commodity boom and response to out of control inflation in the USA and depreciating US dollar. The rapidly increasing costs of these metals will be reflected in goods we buy, like batteries.
  • by huckamania ( 533052 ) on Thursday May 17, 2007 @01:44AM (#19157131) Journal
    Any fire alarms you have should not be using rechargeables. It will usually say so on any new alarms you buy.
  • Re:Voltage. (Score:5, Informative)

    by inviolet ( 797804 ) <slashdot&ideasmatter,org> on Thursday May 17, 2007 @02:06AM (#19157271) Journal

    My baby monitor uses AAs, and I *can* put nicads or nimhs in, but they go dead just from self-discharge as fast as they do from use, so I stick to cheap Kirkland alkalines.

    The new Sanyo Eneloop [thomasdistributing.com] NiMH batteries don't have that problem.

    I recently $wapped out my vast collection of piss-poor Energizer (2500 mAH) AAs for Eneloop (2000 mAH) AAs, and there's no going back!

  • Re:Voltage. (Score:4, Informative)

    by norton_I ( 64015 ) <hobbes@utrek.dhs.org> on Thursday May 17, 2007 @02:47AM (#19157471)
    Any device which will not run on 1.2 V is poorly designed. Alkaline batteries drop in voltage nearly linearly over their lifetime from 1.5 V to about 1.0 V. Devices can and should run over this full range of voltages. NiMH batteries, by comparison, stay roughly 1.2 V for most of their charge cycle. There is simply no excuse for designing something that does not work for half the life of an Alkaline battery.
  • Re:Costs? (Score:2, Informative)

    by mpsheppa ( 1088477 ) on Thursday May 17, 2007 @05:28AM (#19158309)
    I'm not too sure on the details of the US economy and inflation in the US might well be related to a depreciating US dollar and a depreciating US dollar would have some effect on metal prices. However these effects are very minor compared to metal price rises which are actually a result of increasing demand, mostly notably from a booming Chinese economy, outstripping supply.

    On your question of costs, according to lme.co.uk, Aluminium is currently $2,185 per tonne and Zinc is $3,850 per tonne, so I wouldn't be worried about the raw metal cost since Aluminium is cheaper. Anyway, neither of these costs is likely to be at all significant when making a battery.

    In the last 2 years the Zinc price has gone up about 300%. By comparison, Aluminium has only gone up abut 60% in the same time period. The price of Aluminium is probably less affected because its cost comes more from the highly energy-intensive manufacturing process rather than the discovery and mining costs which would more heavily affect Zinc.
  • Re:Voltage. (Score:2, Informative)

    by Anonymous Coward on Thursday May 17, 2007 @07:03AM (#19158795)

    I suppose you know a lot about electronics design to be making such a judgment.
    Yep, I worked for 4.5 years in an electrical engineering firm, designing the electronics for hand-held consumer products, with a particular focus on the supply side.

    In particular, consumer products that can't deal with 1.2v cells simply have a supply-side electronic design that is 30+ years old. A lot of old designs get reused over and over again, as their patents have expired and the designers find it easy to replay the same theme over and over again.

    Although it generally costs no money to design and build something that works properly using 0.9 to 1.8 v cells, some manufacturers like to milk old designs well beyond their useful life, because any engineering or manufacturing change costs at least some money.
  • Powertop (Score:3, Informative)

    by repvik ( 96666 ) on Thursday May 17, 2007 @08:10AM (#19159211)
    Useful link for saving power on Intel hardware: http://www.linuxpowertop.org/index.php [linuxpowertop.org]
  • Re:Costs? (Score:2, Informative)

    by TimSSG ( 1068536 ) on Thursday May 17, 2007 @12:14PM (#19163643)
    The price of energy is rising faster than inflation. Tim S From http://en.wikipedia.org/wiki/Aluminum#Aluminium_me tal_production_and_refinement [wikipedia.org] Aluminium electrolysis with the Hall-Héroult process consumes a lot of energy, but alternative processes were always found to be less viable economically and/or ecologically. The world-wide average specific energy consumption is approximately 15±0.5 kilowatt-hours per kilogram of aluminium produced from alumina. (52 to 56 MJ/kg). The most modern smelters reach approximately 12.8 kWh/kg (46.1 MJ/kg). Reduction line current for older technologies are typically 100 to 200 kA. State-of-the-art smelters operate with about 350 kA. Trials have been reported with 500 kA cells.

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