Which is which

Gen 4 NiMH look physically different than previous generations of battery module, but still work in all previous generations. Lithium on the other hand are not just rare, but won't work on any of the previous generation and don't look anything like them.

It'd be way faster to do a Google image search on what each module looks like, rather than ask on PriusChat

 

You usually look up the part by VIN to ensure you get the right battery otherwise you would have to know which models came with NiMH and which came with Lithium. I would expect the part numbers of the batteries (NiMH v Lithium) to be different.

What specifically is the issue you are having?