In the above settings:
Icon On: if the voltage falls below this level, the low battery icon is turned on
Icon Off: once the low battery icon has been turned on, the voltage must rise above this level to turn it back off (hysteresis)
Blink On: same as Icon On, but for the icon blink / audible alert
Blink Off: same as Icon Off, but for the icon blink / audible alert
Example, using the default NiMH settings above:
1. If battery level falls below 4.47V, the icon will be turned on "solid". It must rise above 4.55V before it will be turned off.
2. If the battery level falls below 4.31V, the icon will blink and the audible alert will sound. It must rise above 4.44V to stop blinking / silence alert. If it rises above 4.44V but is still below 4.47V, the icon will be on "solid" (see #1)