as it say when you buy battle funds,you also share the BF with your account on BFP4F.
http://battlefield.play4free.com/en/
Battlefield play 4 free
its basicly BF2 but smaller,with less maps,4 total,1 original,its there other cash cow that will never leave beta.
Just make sure u use the same email for bfp4f.

And if youve already been playing either BFH or BFP4F, DO NOT, i repeat, DO NOT buy AP here to get the cheaper battlefunds, because they do not state this anywhere but on a few forum topics, but you cannot buy battlefunds with AP on ANY old EA account before the whole EA & aeria hookup thing, you have to make a new account if you want to make use of the cheaper battlefunds provided at aeria games.