Tesla team recharging at a Supercharger stop while traveling on its Cross Country Rally last weekend. Source: Tesla's official Twitter feed.

On Sunday, a team from Tesla (TSLA 3.91%) driving two Model S cars crossed the finish line in a cross-country drive. The two fully electric vehicles made the trip only charging at Tesla's Supercharger stations. More importantly, however, Tesla recorded a record for the lowest charge time for an electric vehicle traveling across the country. But just how convenient is the route?

Killing range anxiety
One potential threat to demand for fully electric vehicles is range anxiety, or the concern that there are not sufficient charging stations for long-distance travel in an electric vehicle. While making long-distance travel viable will certainly help minimize range anxiety, making it convenient would be an even better antidote.

For instance, the bare minimum number of charging stations on a route may enable long-distance travel, but it will likely take more than the bare minimum for the route to feel convenient. Even more, charging can be inconveniently slow, or it can be expedient -- obviously, the faster the charge, the better.

Taking a look at Tesla's recently completed cross-country route may give investors a glimpse of just how convenient Tesla plans to make its Supercharger network. To assess the convenience, let's take a look at the two major factors that go into charging convenience: charging speed and charging station density.

Charging: It's no secret Tesla's Supercharger stations are better than the typical charging infrastructure. Roughly 16 times faster than the typical public charging station, a Supercharger can give a Model S a 50% charge in 20 minutes or an 80% charge in 40 minutes. The Supercharger network was recently named "Technology of the Year" by AOL Auto. 

Thanks to fast charging, Tesla's Cross Country Rally team managed to complete the drive in just 76 and a half hours last weekend, despite "road closures, detours and traffic delays" as a result of a Colorado blizzard that cost the team eight hours. Other challenges included blinding sand storms, freezing temperatures, and heavy rain.

Charging station density: But how dense is the cross-country route with charging stations? Is it set up to handle both the 265-mile range and the 208-mile range Model S?

Currently, the Supercharger stations are approximately 120 miles apart, spaced for both the 60-kWh and 85-kWh vehicles. Tesla says it is adding additional stations along the route for greater density.

Solid progress
Currently, 80% of the U.S. population is now within 200 miles (just enough for a 60-kWh Model S) of a Supercharger station. By the end of the year, Tesla plans to have 95%-98% of the U.S. within range of a Supercharger.

While it's unclear just how convenient Tesla plans to make coverage over the long haul, the company's ambitious short-term achievements and its current goals suggest that Tesla doesn't plan to slack on the network. This is good news for Tesla investors; a convenient charging network is a key factor in the customer experience of driving a Tesla vehicle.