With a bit of trouble, it doable to add points of interest to R-Link. In this country, R-Link (Tomtom) while not a bad navigation system at all, is not very pretty usable for the charger networks. User MartijnEV maintains a separate multi-sourced KML with only and all the 22 and 43 kW chargers in the country. It sits happily in Google’s My Maps and downloaded for offline usage in Maps.me on my phone.
Things snapped together as Jana Höffner described the procedure (in German) to put OV2 files in your R-Link and Pieter, who also made CanZE’s icon, found a snappy website to convert KML straight into Tomtom’s OV2 format.
Follow the links to get the gist of it. MartijnEV decided to publish the ov2 files in parallel with the KML. Instructions, with alle relevant links open when you click that yellow PC alike symbol in the far North of the map.
Edit: More generic instructions (in German) can be found in the goeingelectric wiki, including those for Linux.