I use these http://www.amazon.com/gp/product/B010P2BQ2S?keywords=BL-51YF&qid=1447201273&ref_=sr_1_2&sr=8-2

Not OEM, but not pretending to be, and comes with the cradle. They aren't quite as good as the one that came with the phone, in particular the battery percentage tend to jump around a bit, but overall I'm happy with them.

http://www.amazon.com/gp/aw/d/B010P2BQ2S/ref=mp_s_a_1_1?qid=1447185434&sr=8-1&pi=SX200_QL40&keywords=lg+g4+replacement+battery&dpPl=1&dpID=41tleyKlPQL&ref=plSrch great battery for the price