Yes, the wise BEV shopper when confronted with an EPA range of 400 immediately reduces that in his mind to a "working range" of 300 miles or so.Now I am goin g to throw another wrinkle back into the mix based on my extremely limited understanding of BEVs and lithium battery care. If we say the range for the 180kWh R1S is 410 Miles as is currently stated it is my understand that to take the best care of the battery you typically want to drive in the 15% to 85% range
Tesla's guidance is to not discharge below 20% nor charge above 90% on a regular basis. They also advise not using Super Chargers unless it is necessary. They taper charge rate when SC are used (might start at 2.5C and taper to 0.4C or less) so that it is actually faster to stop twice and charge to 55 - 60% than to charge once to 90 or 100%. Now this is not a problem for daily use. You set the charge limit to 80% and plug in each night when you come home. You leave the house every morning at 0.8C. A long trip is a different matter. It is perfectly OK to charge a Tesla to over 90% in preparation for a long trip and discharge below 20% if necessary. It is doing this repeatedly that decreases battery life.rarely charging to 100% (especially with a DC charger) and also don't want to drop below 15% as both of those ranges "hurt" or shorten the life of the battery. Would those of you with BEVs today agree that 15%-85% is the sweet spot for battery care and longevity?
Take all that as an example of what you might expect to encounter. Rivian is not using the same battery technology as Tesla and they may have a different set of instructions for us to follow but I don't imagine they will be too much different.
All true. The big difference with BEV is that you get much (but not all) of the mass related energy consumption (acceleration, ascending hills) back but you don't get any of drag loss, which is proportional to the square of airspeed (groundspeed ± windspeed) back.I realize just like with an ICE vehicle fuel economy is not completely linear. IE: Uphill, Downhill, headwind, heavy foot all affect absolute range.
That is true but keep in mind that on a road trip you don't typically shave 15% - 20% off the ends. I start most road trips at 0.9C (90% SoC) and have finished legs with as little as 0.11C left in the tank.But if I take 410 max range as a best case scenario and I attempt to keep the battery between 15% and 85% as much as possible then my best possible range shrinks to 287 Miles between charges(shaving off 15% of range on either end of the battery).
A more important consideration is as to what your actual consumption is per mile. If the EPA rating is 410 miles and you drive at a rate that mimics the EPA test conditions you will get 410/C miles or 4.1 miles per percent SoC taken. In the Teslas you tell the autopilot where you are going and a graph connecting current (departing) SoC at the left side and estimated SoC at the destination on the right. As you make the drive a second line appears on the graph indicating the actual SoC at your current location and an updated estimate of what will be left at the destination based on the drive so far. This is your most powerful tool for managing battery. If it looks as if you won't have enough margin at the destination you can take corrective action as by slowing down, turning off HVAC or stopping for a supplemental charge. I will be absolutely astonished if Rivian does not offer a very similar tool.
Part of what these tools do is show you the average watt hours used to travel various distances. On of the first things you want to do is figure out what your number is under various sets of driving conditions. I have seen, for example, nothing more dramatic than heavy rain increase consumption from 300 Wh/mi to over 400. The implications of this are abviously a decrease in range to 3/4 of that attainable without rain.
My advice at this point is always the same: Plug it into ABRP and see what it tells you. If I do that it says 20 hours of driving with 2:39 charging spread over 6 charges i.e. it would have you making an extra stop each day. The longest stop would be for 38 minutes. In no case would SoC be larger than 87% (except for the departure from home which would be done at 90%) and in no case would you arrive at less than 20%.Today if I leave Austin Tx at noon I can be at Disneyland in Anaheim by 5pm the next day with an overnight stop at the Hampton Inn in Deming, NM which is about the halfway point. I typically make that drive with 2 stops each day but I don't think that would be possible in the R1S especially if I am trying to take the best possible care of the battery.