For three weeks now, my wife and I are the very happy owner of a used Tesla Model S 85 of 2013 with just over 100 000 km (or 60 000 miles) on the odo. It has a rated range of 406 km (252 miles) at full charge. So far, we are very impressed with the car performances and all its features.
Regarding charging, we are in the particular situation where once a week, we have to do a 400 km (250 miles) trip on a fixed schedule. In principle, we could make the distance with a full charge, driving at ~100 km/h (60 miles/h) on flat land, consuming 190 Wh/km (that's 305 Wh/mile), and arrive home close to 0 km of range. But the land is not flat, we need air conditioning or heating, battery will need heating during cold winter days (we live in Quebec), it is not good for longevity to charge the car regularly to maximum range, we often have to do 5-10 km detours to pick up something, and we wish to get back home with 30-40 km of range, just in case. And it’s a bit odd to drive such a car close to 100 km/h… Fortunately for us, in the middle of the trip, we have access to a NEMA 14-50 plug for about 2 hours. (Remember the "fixed schedule".) I thought we would be good. Not completely...
Here is some info I gathered on forums and blogs, some of I didn’t understand correctly before, and that some other new user might find useful. I hope this post doesn’t contribute too much to the noise!
Other things less or not related to battery and charging that I found useful:
That’s what I had in mind so far. Hope it’s helpful for someone. Sorry for the long post.
Regarding charging, we are in the particular situation where once a week, we have to do a 400 km (250 miles) trip on a fixed schedule. In principle, we could make the distance with a full charge, driving at ~100 km/h (60 miles/h) on flat land, consuming 190 Wh/km (that's 305 Wh/mile), and arrive home close to 0 km of range. But the land is not flat, we need air conditioning or heating, battery will need heating during cold winter days (we live in Quebec), it is not good for longevity to charge the car regularly to maximum range, we often have to do 5-10 km detours to pick up something, and we wish to get back home with 30-40 km of range, just in case. And it’s a bit odd to drive such a car close to 100 km/h… Fortunately for us, in the middle of the trip, we have access to a NEMA 14-50 plug for about 2 hours. (Remember the "fixed schedule".) I thought we would be good. Not completely...
Here is some info I gathered on forums and blogs, some of I didn’t understand correctly before, and that some other new user might find useful. I hope this post doesn’t contribute too much to the noise!
- I though that the access to the NEMA 14-50 would be sufficient as I initially thought that I could get 50 A, maybe 60 A from such a plug. But by North-American regulations, things connected to a NEMA 14-50 plug are not allowed to draw more than 40 A from the plug, event if the connector is related a 50 A breaker. This is the case of the Tesla Mobile Connector provided with the car; it wont let you dial more than 40 A on the charge current limit. In my case, the 220 V/40 A plug gives me 45 km (or 28 miles) of rated range per hour of charge. So +90 km of rated range for our trip. With that, we can currently do the trip at ~110 km/h, including a couple detours. But during winter, with interior and battery heating...
- A possibility would be to have access to a Tesla Wall Connector (TWC) at that mid-trip location. The TWC can provide up to 80 A, i.e. 90 km of range/h in our case. But it has to be connected on a 100 A breaker. Like most houses in Quebec, the house where we can plug at mid-trip is equipped with a 200 A main electric panel. 100 A is the half! Installing a TWC would actually require changing the complete electrical panel and outdoor post to 250 A. Plus, above 60 A, it require a safety contactor next to the TWC. All that is not cheap, considering it would be used only once a week for a couple of hours. And this is not our home! Not a solution.
- We have only two SuperChargers in Quebec. One of them is 1 km from home, so it doesn’t help (we are already fully charged when we leave, or nearly empty but near the home plug when we come back), and the other is not in the direction we’re going. 2-3 more are planned. They will be very practical for travelling to the Maritime Provinces, which is their purpose, but won’t be of any help for our weekly trip. There are also some destination chargers at hotels, but they are reserved for guests, and they are often only 40 A instead of 80 A, i.e. not better than the NEMA 14-50 plug we have already access to.
- We are blessed to have ~20 CHAdeMO chargers in the province, including one along our route. They provide 50 kW of charging power. That’s 5 times what we can get from the NEMA 14-50 plug (nearly 10 kW), and nearly half the power of a SuperCharger (120 kW). It costs 10$/h, charged to the minute IIUC. It requires an adaptor (which now exists, a saga of its own apparently) at a cost of 500 CAD+tx. Much cheaper than changing the electrical feed at someone else house! But it involves waiting ~30 min in the middle of nowhere (in the case of that specific charger) to get 100 km of rated range. Still, this is likely to be our solution during winter if/when maintaining the battery and the car warm requires so much from the battery that we cannot drive at a reasonable speed.
- There are also about 400 other chargers in the province, but most of them are 220 V/30 A. This would presumably give us 34 km (or 21 miles) of range/h. For us, this is useful only in case of emergency (i.e. for some reason we didn’t manage to recharge and are approaching 0%), or if we stay at a hotel with such a plug. We don’t usually stay at a restaurant like 3 hours, or enough to get significant range from that sort of plug. But at least, they exist, and there are so many of them, we would have to be very unlucky to end up at 0% before being able to reach one.
- Speaking of winter, we will certainly heat the car while it is still plugged, and program the charging so it ends just before we leave, so the battery is warm, and we don't draw all that power from the battery during the first few km. Because of battery and interior re-heating, people report that making multi-stop trip with >30 min breaks during cold days is an absolute range killer. (By cold, here, I mean -20 C or 0 F and below). Continuous trips in cold weather are not that bad, apparently. Looking forward to see that.
- Regarding the battery capacity degradation, heat and full charge are the enemies. (See port #2 in this tread, which cites articles.) It makes a lot of sense. As most chemical reactions, those leading to degradation require energy and heat to occur. Quebec is a good place for coolness, so that’s one. Currently, I keep the charge below 50% during the week, and increase to 95% just before the weekly trip. I read a post where someone who started keeping the charge below 50% even reported regaining a couple of km of range. I’m eager to see that! But I guess it's more related to "battery balancing". Next point.
- People report a range increase after "balancing the battery", which requires to keep the charge at 100% for a couple of weeks. But this is a different point than degradation: the battery may give as a whole a lower capacity than it actually can because some of its cells are more degraded and discharge faster, preventing the other cells that are plug in series with them to fully charge or discharge. By balancing the battery pack, you allow the system to recalibrate and find which battery has which capacity. As a result, the more performing ones will be able to charge and discharge more than the weaker ones. See wikipedia for mode details. So you may regain some rated range because the better cells are then allowed to charge more. But you are not reversing the degradation process of the weak batteries. If anything, you accelerate it, because you put the battery in one of the conditions that accelerate degradation: full charge.
Other things less or not related to battery and charging that I found useful:
- VisibleTesla is a great tool! Big thanks to jpasqua and the people who figured out the commands send to Tesla servers. Be sure to download the latest version (as of this writing the 0.50 series) as there have been some changes on Tesla side that prevent the previous versions to work. A couple of times so far, I had to reboot my Mac to make it work. Not sure why.
- When the car falls into deep sleep, it is often hard to wake it up, either with Tesla’s Android app or with VisibleTesla. There is an option to "stay connected" in the car controls, which helps. In my case, it decreases the range by a couple of km during the night, vs. nearly 0 km when it’s not on and the car is in complete deep sleep. Your choice.
- The car responds to several voice commands by pressing the "voice button" (top right button on the steering). See this page for a summary. Among others, you can search Slacker for a tune by saying "Play" followed by the name of the group, song, etc.
- It’s really cool to have the traffic showing up in real time on the screen. However, the time predicted by Tesla’s trip planner seems to be based on official maximum speed, not on actual trafic speed as Google Maps does. It’s probably because Tesla wants, above everything, be able to compute and show a rated range curve for the trip, to which you can refer in order to know if you actually meet the rated consumption and end the trip with the predicted range left. Fair enough.
- But the trip planner does not let you add waypoints, and will prefer a route that uses less power, event if it takes a few more minutes, and not considering trafic, AFAIK. It would be very practical to be able to predict the range left after a trip that does not go straight to the plug one is planning to be the next. And it would not defeat the purpose of "the curve".
- The car map does not show the other charging stations than Tesla’s SuperChargers and destination chargers. For that, tesla.plugshare.com will be your friend. Its interface is made easy to use on the car web browser, and it provides info about whether the plug is public or reserved for clients, the cost if any, whether you need a registration or a card to access it, users comments, etc.
That’s what I had in mind so far. Hope it’s helpful for someone. Sorry for the long post.