Alkaline cells have an impressive energy capacity, usually
greater then 2500mAh. But this is only one of several factors that affects
the performance of a cell. At certain points in their operation Digicams
have extremely high power demands. The power a cell or battery can deliver
depends on both the voltage it can provide, and the electrical current it
can deliver (the power supplied is actually the voltage multiplied by the
current). The voltage is limited, it is fixed by the chemistry of the cell,
so the only way to deliver that power is with a large current. The
essential problem with alkaline batteries is that they have great difficulty
providing these large electric currents.
Alkaline cells are brilliant, however, in the right application. For low
power devices, or devices that are used infrequently e.g. doorbells, radios,
remote controls etc., they are superb. They have a huge energy capacity,
and a shelf-life of several years. . (Many
pro-photographers keep some high quality alkalines in their bag so that they
can always take a few shots if their rechargeables run out etc.)
