Use account balance for cell phone bill?

You can’t transfer your Apple Account balance to another payment method. From the article below.

About unused Apple ID balance

You can't redeem or return Apple Gift Cards, App Store & iTunes Gift Cards, or unused Apple ID balance for cash, except as required by law. If your jurisdiction allows for refund of redeemed gift balances, you can contact Apple Support to request a refund. - When you contact Apple, please include the following information:

Your Apple ID.   -

The refund amount.

Your current shipping address.

Apple ID balance - View  *

To learn 'What you can buy with your Apple ID [Apple Account] balance', click here --> What you can buy with your Apple Gift Card or Apple Account balance - Apple Support

Since that doesn't include phone charges, and as outlined earlier you can't transfer your balance to another place, the answer is basically "no".