The ELPH 180 uses a NB-11L (or NB-11LH, basically the same) battery. So any adapter or DC coupler meant to power a NB-11L–type battery compartment should work.
Canon's ACK-D90 is the AC power adapter + DC coupler meant to power cameras that use an NB-11/L/LH battery. So any 3rd-party that is equivalent to it should work just fine.
Apparently, the DC coupler (the "dummy battery") part number is DR90 (or DR-90). I can't find it at Canon's site, but that's what many 3rd-party sellers seem to call it.
As far as using the product you show, if it were me, I would go with it. Battery-powered devices have voltage regulators precisely because the voltage output of batteries is never exactly what its label says. The labeled voltage is nominal. As the charge in a battery is depleted, its voltage drops. And that voltage drop profile is highly dependent upon on the battery's technology (alkaline, NiCad, NiMH, Li-ion, etc.). Bottom line, the camera will never rely on exactly 3.6V from the battery, so they much expect for and regulate varying input voltages.
Checking Canon's compatibility page for the ACK-D90, it only works with red ELPH 180's, or refurbished red or silver ELPH 180's. ;-)
(Note: I'm joking about the compatibility. That what Canon's site says, but clearly, the compatibility isn't depending on the color of the camera that otherwise is the same.)