I am planning a long road trip for my Tesla Model Y. In the past, I would charge my Tesla to 100% at home and at each rest stop according to my Tesla App. It could take me 40 to 45 minutes to charge at the various rest stops and then I would be on my way for 200 to 250 miles. As the trip developed, I ended up stopping at a local rest stop for a bathroom break even if they did not have a charging station. So, my trips ended up taking 20% to 25% longer than an ICE car. This started to bother me so I researched how I can reduce the trip for my trips.
The first clear recommendation is to start your trip at 100% or close to it. This is applicable for people with chargers at home since it is cheaper and you are not really concerned with the length of time it takes to charge. The only downside that I can see is that the regenerative braking is shut off when you are at 100%. I will acknowledge that regularly charging your Tesla to 100% will stress out the battery resulting a reduced lifespan.
As to the strategy for charging on the road, you need to start with some understanding of the battery charging timelines. Tesla (and other EV’s) batteries charge the fastest at the lower end of the charging percentage. This means, that it may take 20 minutes to charge from 15% up to 75% (or 80%) but it may take another 20 to 25 minutes to go from 75% (or 80%) to 100%.
On my Tesla, the extra 20% equates to approximately 60 miles. So, I have to ask myself is the 60 miles worth an extra 20 minutes? I came to the realization that by only charging to 80 will result in 2 to 3 extra charging stops. My last trip of 1,200 mile required 8 stops with an average charging time of 45 minutes for a total of 360 minutes.
If I only charge to 80% (with each stop taking 25 minutes) but need to add 3 additional stops that would take 275 minutes, a savings of 1 hour 25 minutes. Looking at it another way, I can stop 5 more times to charge my Tesla to 80% and it would still be faster than I charge to 100%. Looking at it this way, it makes no sense to wait to charge your Tesla to 100% if you have a steady supply of charging stations.
For those with range anxiety, there is no stretch from Florida to New York without Tesla or other charging stations that come close to 100 miles. In fact, you can find most charging station almost every 40 to 50 miles. I did find that in Maine there is a stretch of highway that is approximately 103 miles without any charging stations. With that being said, there is no reason that you need to charge your car to 100% in fear of not reaching the next station. My recommendation is to start at 100% and then charge to 80%. It will be faster and you will preserve your battery.