At what temperatures should batteries be charged and discharged?

Discharge should take place at room temperature. At temperatures below 0° C, the capacity of the batteries decreases considerably.
Charging should preferably take place in the range of 10 - 35°C, as this is where the batteries have the greatest capacity.
With NiMH batteries, the handset interrupts charging at temperatures above 45° C, with LiIon batteries below 5° C and above 40°-45° C, as the batteries must not be charged outside these temperatures.