echo 1 stag arms m16a4 help

Hey guys I just received my echo 1 stag arms m16a4 and I really like it. The only problem is the battery compartment is to small even for the battery they (airsoft GI) sent me. I can fit it in there but it is an extreme hassle, I have to jam it in there and when I pull it out it scratches the covering on the battery. I am considering buying a new stock but I really don't want to. Is there any solution to this?

if you have to you could un screw the butt plate and put it back on each time but that is probably just as bad

mabye you could buy a butt plate that your battery fits in but i don't know where you can di that

ya I have thought of that I guess I will go try it

I also have another question, how can I tell the battery it cam with is nimh or nicd? thanks