Question about Garmin Drive 52 Full EU MT

You can also charge the navigation device with a USB charger or with a USB connection to the PC/laptop.

The navigation device is only installed when we use it from time to time. Because of the small battery capacity, it then only has a small charge when switched on, which is enough (or not) for a short time (a few minutes).

In principle, yes; the navigation system has a USB connection and can also be charged via it.
The question is what you connect it to, i.e. how much voltage you apply.

Unfortunately, I can't give you an effective duration, because it usually depends on the adapter.
However, it is usually already empty when I switch the device on again after a week or so...
The old one (also Garmin) had a certain residual charge for months (even in winter).
Gut feeling says "weak battery".