Where does spermatozoa attain maturity during its passage?

While passing through epididymis, sperm become motile and their surfaces and acrosomes undergo final maturation steps. Fluid within the epididymis contains glycolipid decapacitation factors that bind sperm cell membranes and block acrosomal reactions and feilizing ability until the factors are removed as pa of the capacitation process in the female reproductive tract. Ref: Mescher A.L. (2013). Chapter 21. The Male Reproductive System. In A.L. Mescher (Ed), Junqueira's Basic Histology, 13e.