Not sure how familiar you are with plugshare. Quick and dirty overview.
1) go to www.plugshare.com
2) search for a city / town. It looks like a google map, sort of. There's a " + / - " to zoom the map in / out. If you "hover" your mouse over a button / item, it generally tells you what it does.
3) One the left of the screen, you see pop-down items : Legend, Filters, Pay with PlugShare, Recent Activity, etc.
4) click on "Legend" to see what the little symbols mean ( "green teardrop" means "Public L1 or L2", "Orange teardrop" mean "DCFC", etc.) Then hide it - it's simple to remember.
5) click on "Filters". There are sub-menus "Plugs", Min Power", "Networks", "Include", Amenities", "Min PlugScore", "Extras"
5a) zoom out the map in order to show the full area that you will be driving for your trip.
5b) In Filters, click on "Plugs", and UNselect everything except for "CCS/SAE" (because you are looking only at DCFC sites - later you can add J-1772 in those places you will stop in order to charge overnight via L2). close the "plugs" pop-down menu.
5c) Make sure to check the settings (inside the Filters area) for :
- "minimum power" should probably be "0 kW". You *could* set it to 50 kW so that you don't see the old, slow 20-25 kW DCFCs. But to start, try "0 kW" (i.e., all of them)
- "Include" should have "Payment Required" and "Currently in use" selected, so you see pay chargers - not just the free ones AND ones that somebody is using right now (respectively). UNselect "Coming Soon" : those aren't turned on yet, so they aren't going to be much to you on your trip. (they have a "wrench" on them)
- "Amenities" : all unchecked (although if you check only "Lodging" and set "plug" to "J1772", you an identify hotels that either have on-site charging, or there is charging very close by)
5d) click on "Networks", and then "toggle all" button to turn OFF *all* the networks. Now just click on ONE (say, electrify America). Look at all the sites that are available. Slowly go thru the different providers (prob starting with EVgo, ChargePoint, GreenLots since they tend to be the biggest ones, but you might as well go thru all of them). You UNselect the previous choice and then SELECT a single new company to see what each one has available. You have now identified the networks that have the most units in the area(s) that interest you. Write those down. Consider getting a free card / account at all of them. Note that there is one "network" called "Other". That is (obviously) all the other networks, including "other networks / non-networked" .
You can also play a little bit, and (say) :
* In plugs, select "J-1772" as well (green teardrops). Zoom the map in close on/around the areas where you are planning on stopping (for several hours, overnight, or several days). You now see all the charging locations in areas where you will be spending time.
* In "include", UNselect "Payment Required". Now it is showing you all of the free charging locations. Maybe there is free charging downtown, and you pick a hotel nearby. Or near that museum of basket-weaving the wife wants to spend 7 hours in. Or near that park you want to hike in. Or just down the street from the in-laws where you will be staying for 3 days.
* In “include” section there is also “residential locations”. Take a look at those (they are blue / aqua / teal teardrops with a house icon). These can also be lifesavers. They are homeowners (generally with an EV) that will let you charge at their home in an emergency. Sometimes there are none, sometimes a few, sometimes a lot. (There are probably over 100 with 6-10 miles of MY house, but, well , Silicon Valley tech geeks and all.)
Hope this helps ...
Oh, and you *might* be able to use Chevrolet dealers in emergencies. You can identify dealerships along your travel route, maybe around times you would eat anyways, and call them directly and tell them you are traveling through and ask if you could use their charger for an hour or so. You would of course be willing to post on yelp (or elsewhere) how great they were, nice, friendly, accommodating, willing to help out a chevy owner who was just passing through, etc. Since the dealers (that have them!) tend to have the slow units, it would be most advantageous to use them to "top off" from 75%-100%, since the car will only charge at about 25 kW at that level of 'fullness' anyways. Or simply to bridge a gap that you wouldn't otherwise be able to make.)
Ditto Harley dealerships (maybe it is only in CA, but a BUNCH of Harley dealerships have installed 24 kW DCFC units because Harley announced an electric Harley bike). In plugshare, those sites are generally listed under the 'network' : "Other" .