1.    Provides basic characteristics on 10 basic battery chemistries.
2.    Also provides specific batteries for tasks by manufacturer for 23
manufacturers.

    http://www.energy-sales.com/lithiumion.html

1. is fairly basic but allows you to compare energy density per kg and per
litre, useful temperature ranges, recommended operating loads, self
discharge rates & shelf lives.

________________

Another good battery specification site

        http://www.batteryspecialist.com/Merchant2/

eg Panasonic battery specs

         http://www.batteryspecialist.com/Merchant2/panasonic.html

        Regrettably specs given vary with battery type.
        Some are superb, giving mAh, pulse mA, recommended mA etc

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