La Crosse Technology BC-900 AlphaPower Battery Charger from:
La Crosse TechnologyCharging Ni-MH batteries is the result of a compromise. A low current
is gentle on the battery and maximizes its lifespan, but a full charge
takes hours.
A high current will recharge the battery much faster, but put more
strain on it, causing it to wear out prematurely. It also requires
careful monitoring of the battery's electrical characteristics to
prevent damage.
Most of the chargers you can find on the market today use one or
the other of these methods. The fast chargers, especially the cheap
ones, excel at one thing: destroying perfectly good batteries, because
they lack the monitoring circuitry to control the charge current and
detect when the battery is full. The slow chargers are usually better,
mainly because it's harder to design a really bad slow charger.
Unfortunately... they're slow.
The BC-900 is a completely different breed: it lets you pick the
charge current for each individual battery, has very sophisticated
monitoring circuitry that controls the charging process, and is also
capable of "renewing" batteries by running full controlled
discharge-recharge cycles.