How do I make my iPod 5 gen stop asking for my Apple ID password to update an app?
Agree with @Tyson, updates do not require a password in recent versions of iOS, presuming you are signed into the App Store with the account that originally purchased (or acquired) the app.

If you have multiple accounts, and each account has downloaded one or more apps, you are always going to be prompted for the password if the account that is signed in is not the same one as the account that purchased the app that you are trying to update.

It sounds like in your case you might have changed Apple IDs, or used somebody else's when originally acquiring the apps? In which case, you can sign out of the store (App Store > first tab > "Sign Out [your email]" at the bottom) and sign back in with the account that acquired the apps you are trying to update.