I tested many LIPO for my 2/2.5 inch quad and here the best you can get. It it not the chepeast LIPO that you could find, but for long term usage and long fly here the best:

58a75c5d-35a9-4f67-91f1-a79408160b01

618JRMwkMVL.SY355

GNB-11-1-V-550-mAh-80-160C-3S