Yes, spare or loose dry-cell [e.g. AAA, AA, C Cell, D Cell and 9-Volt] and nickel-metal hydride batteries can go in your carry-on bag, but not checked luggage.
The restrictions that apply to dry-cell and nickel-metal hydride batteries:
Not sure if you can take it? Contact your airline and check with them.
Batteries can overheat and catch fire.
You will be asked to relinquish all dangerous or prohibited items found in your carry-on luggage. If you refuse:
AvSec X-ray bags going onto aircraft to ensure there is nothing dangerous in them.
For more information, see Retrieving your removed items.