Canon 188A - Manual (Page 9)

Remove the batteries if you do not
expect to use the 188A for about three
weeks or longer
Set the main switch to OFF when
flash photography Is finished
When the batteries become exhausted,
replace all four at the same time with
four new ones of the same brand
Since battery performance deteriorates
in low temperatures, keep the batteries
warm until just before use. Keep a set
of spare batteries warm and alternate
them with the loaded ones so that
warm batteries are always in use
In temperatures below 0“C, the use of
fully-charged Ni-Cd batteries is recom­
mended When recharging Ni-Cd bat­
teries. follow the instructions of the
battery manufacturer
Each brand of Ni-Cd batteries has its
own terminal system Be sure to use a
type which is suitable for this flash.