My cordless laptop mouse doesn't seem to hold the battery in place very well?

My cordless, battery powered mouse is virtually brand new. I only used it a handful of times before it just stopped working. I figured the battery needed to be changed out so I bought a new battery (size AA) and put it in, but still the mouse wouldn't turn on. Later my husband looked at it and he says it's not holding the battery right. The battery kinda wiggles around in the slot, rather than fitting snug. But if you press the battery up angainst the mouse wall, the light comes on. Since I cannot use it if I am holding the battery in place, I would LOVE to know if there are any ideas out there on how I can fix it. Can I slide a small piece of metal or something into the gap??? I don't know what to do, and I hate having to go out and buy another one.