Higher frequencies, as bats use, give finer resolution. This seems impossible for humans, but since we have cochlear implants, there's no reason they couldn't respond to a shifted audio spectrum. Or, just have an external hearing aid that frequency-shifts the sounds (and cancels out the original), together with a higher-frequency sound source.

OTOH, eye implants are probably not that far off.

> Just the auditory cortex of a human brain is many times larger than the entire brain of a bat.

This really startled me. It seems plausible that we could do as well, with early training etc. Plus, I imagine that some of the higher-order processing of the occipital cortex would also be seconded.