The Digital Camera Battery: 
Which ones work best?

 excerpt from imaging-resource.com

Some digital cameras come with proprietary rechargeable LithiumIon battery packs in the box - If you own one of these, there's no issue of which brand and type of batteries to buy, just be sure to get an extra battery pack and keep it charged as a spare. 

A great many digicams however, use conventional AA-size batteries. For the AA-equipped cameras, it's well established that standard alkaline batteries are almost completely worthless in most cases. You want high capacity Nickel Metal Hydride (NiMH) rechargeable AA cells and a good charger. There's quite a range of performance between brands and models of NiMH batteries.

The rankings, top to bottom:

Battery brand & rated capacity		Watt-hours (4 cells)	mAh	Min
	Powerex 2200	10.10	2069	134.1
	Sanyo 2100	9.66	2013	131.8
	Uniross 2100	9.41	1867	124.0
	Powerex 2000	9.04	1856	120.5
	Nexcell 2100	9.00	1886	126.9
	Nexcell 2000	8.91	1861	122.8
	Sanyo 1850	8.89	1841	123.2
	Energizer 1850	8.88	1827	121.7
	GP 2000	8.86	1845	121.5
	Kodak 1850	8.84	1813	120.5
	Jetcell 1850	8.81	1815	121.0
	Panasonic 1950	8.65	1822	121.3
	Powerex 1800	8.46	1726	112.0
	Nexcell 1800	8.32	1737	114.5
	Duracell 1800	8.21	1707	112.0
	GP 1800	8.21	1690	112.6
	Sony 1750	8.17	1683	112.1
	Energizer 1700	8.01	1646	109.4
	Kodak 1700	8.01	1667	112.3
	Olympus 1700	7.84	1631	107.3
	Powerex 1700	7.79	1618	109.0
	Kodak 1600	7.56	1569	105.4
	Radio Shack 1600	7.49	1537	102.0
	Powerex 1600	7.44	1527	101.3
	Rayovac 1600	7.31	1479	100.0
	Panasonic 1600	7.10	1457	96.9
	GP 1600	6.83	1428	96.5
	Panasonic  (Alkaline cells)	3.66	774	56.0
	Duracell Ultra  (Alkaline cells)	3.66	781	57.0
	Energizer  (Alkaline cells)	3.55	756	55.0

Watt-hours vs mAh

Normally you see batteries rated in milliampere-hours (mAh), a measure of how much current they can provide over time. A rating of 1600 mAh means that the battery should theoretically be able to supply 1600 milliamps (mA) for one hour, or 160 milliamps for ten hours, etc.

It turns out though, that mAh is really only part of the story. What we really care about is how much total energy a battery can deliver. Energy is measured in Watt-hours, the product of voltage and current over time, or volts times amperes, measured over hours. (A milliamp is 1/1000 of an ampere.) To measure total energy, we need to measure the voltage and current moment by moment throughout the battery's discharge, multiply the two values together, and total up all the individual readings.

The Importance of the Charger

The right (or wrong) charger can make a big difference. The worst chargers, in charging terms, produced "charged" batteries with only half the stored energy of ones charged with the best chargers.

for the full battery report, see: imaging-resource.com