Nikon D300 User Manual page 342

My Recommendation: Nikon allows but does not
recommend using certain AA batteries, such as Alkaline
(LR6) and Ni-Mn (ZR6 – nickel-manganese). Its primary
objection to these two types is that they do not work well at
lower temperatures. In
fact, once you go below 68 degrees F (20 degrees C), an
Alkaline battery starts losing its ability to deliver power and
will die rather quickly. You may not get as many shots out of
a set of AA batteries, so your cost of shooting may rise.
However, AA batteries are readily available and relatively
low cost, so some people like to use them, especially in an
emergency. If you do choose to use AA batteries, why not
stick with Lithium types (FR6) since that is the same type of
cell used in the normal Nikon EN-EL batteries and is not
affected as much by a low ambient temperature. You can also
use the Ni-MH (HR6 – nickel-metal hydride) batteries safely
since they are not as temperature sensitive and provide
consistent power.
Battery Order
Custom setting d12 (D300S) and d11 (D300)
(User's Manual – D300S page 280; D300 page 287)
Battery order lets you choose the order in which you want the
available batteries to be used—camera's battery first or those
in the MB-D10 battery pack first.
Here are the screens and steps used to configure the Battery
order (Figure 4-47):
342