Roadtrip at lower charges ended up with faster trip time

[noshadow]

I did the same 500+ mile (one way) trip a couple of times this year so far, and my biggest issue was how long it took to charge. I never got 250kw, and was always crawling at less than 80 at the super chargers. It was easily taking an hour or more to charge. After asking around here, the culprit was I kept the car topped off to 90 or 100 every charge.

I was doing this because it was the winter, I had a cargo roof box, and so I was worried about range so I kept my charge topped off. There are two stretches where there are no chargers in between and I would be driving quite far.

After people enlightened me that I could really ever achieve the fastest charge when the battery was mostly empty, I tried it out. I spent my last trip (4th time doing it) getting to the superchargers at less than 30% charge by not going too high, and there it was, I cut my average charge time from 50 minutes down to about 10 minutes for the same amount of recharge.

I did this on my last drive because I was pretty confident of what my average wh/mile was after taking note of it on the previous trips, so I knew I could make it every time.

 

[NCC81701]

Yes this is because for lithium batteries you can charge at max amperage until the cells are near their max voltage of 4.2V/cell. Once the cells are at or near that voltage then the charger is voltage limited and will have to back off the amperage to keep the cell voltage below 4.2V. If the batteries ever goes over 4.2Vs it will spontaneously combust.

This is why you can get a faster trip speed if you charge just enough + some safety to make it to the next station. This way your average charging speed for the trip will be higher even though you’ll have to make more charging stops.

 

[jcanoe]

If you have not already tried using this app, A Better Route Planner is a very good tool for planning your trips, ABRP will recommend optimal Supercharger stops for your trip. You can access ABRP on your phone; also at A Better Routeplanner

 

[user212_nr]

Using trip planning software like ABRP (A Better Routeplanner) or Tesla's route guidance avoids this blunder.

Glad you figured it out, but sad how many people get the car and have no idea for several months or years (including myself).

 

[TomServo]

The charging speed "throttles" big time after 65%, so if 65% can safely get you to the next SC that's the fastest charging routine than to start a charging session at 40% or 50% and going to say 80%+.

Bjorn's latest charging speed test bears this out. And the Mach-E is a joke after 80%

 

[mark95476]

Yup. I think it takes everyone time to get over range anxiety to purposely aim for low SoC before charging. Nobody wants to get stranded, whether its a gasser or EV. My GF would get nervous when the fuel gauge hit 25% in my old gasser and she would insist on stopping at the next gas station for a refill.

Using trip planning software like ABRP (A Better Routeplanner) or Tesla's route guidance avoids this blunder.

Glad you figured it out, but sad how many people get the car and have no idea for several months or years (including myself).

 

[Zextraterrestrial]

I am for 5% arrival. up to 10% max in the old S ( 97k miles on it w/ many, many 310 mile trips w/ single, or now 2 stops 5% - 70% is best in in that format S now

Y and 3 like about 10% maybe even 15% to start and up to ~75/80% is pretty quick. I'd stop at 60% (15-20 min total chare time) or 90kW rate if its enough to get 2 hrs of driving and chargers are close to the route

 

[Rocky_H]

You may hear people refer to "splash and dash". That's what they are referring to.