Camera Batteries Li-Ion or li-Po

Hi all

Looking for a bit of advice on Camera Batteries

I have been testing quite a few different makes to check on the claimed v actual capacities and noticed something I need help with

I have a number of LUMIX Batteries all listed as Li-Ion and all rated at 7.2volts which is correct for 2 Li-Ion cells as they are 3.6 volts each

But all the third party batteries I have although all printed as being Li-Ion they are all rated at 7.4 volts or 3.7 volts per cell which is what Li-Po cells are rated at.

So are the third party batteries really Li-Po as indicated by their voltage or Li-Ion as printed on the battery.

or are there Li-Ion batteries that are 3.7v per sell or is it something else.

Thanks for any help with understanding this.

Paul