Effect of Free Super Charging for Life to 2019 LR Model X

[RoBoRaT]

How bad is it for battery life if I was to charge a Model X every other week, almost exclusively using Super Charger, to use FREE SC for the life of the X?

The average weekly mileage for this new 2019 Raven LR X will be 100 miles a week, if that.

SC is urban 72kW type, from 20% topping off at 90% SoC every 2 weeks.

What do you think?

Pundits, SMEs, and neewb's opinions welcome.

 

[ajdelange]

If you regularly charge the battery to 91% you will, eventually, get a warning message to the effect that you are going to shorten the battery life and at some point the BMS will step in and limit your charges. If you regularly charge to 90% you won't get any such messages or limitations imposed. This tells you that Tesla thinks that regular charging to over 90% is a bad idea and it is pretty well known that this is the case with lithium batteries. But how bad an idea is it? No one will be able to give you a hard number such as a statement that hard charging reduces the life life of your battery by 0.764%.

It also seems sensible to conclude that 90% isn't a hard limit and that charging regularly to 85% may extend your battery life relative to 90% charging, Again the question is as to how much improvement this might get you. Note also that the president of the company has said repeatedly that charging the car to 90% won't hurt it.

Add to this that your projected mileage of 5,200 mi/yr is well below the 13,000 mile average for the US and I think you will probably be OK with your plan but I certainly don't have any hard numbers for you.

 

[RoBoRaT]

@ajdelange, I appreciate your insight.

It's good to know that charging to NOT more than 90% is looked at OK by Tesla. I did not know that it's the repeated fast charging => 91% that triggers the BMS warning or eventual throttling of SC speed.

Thanks again for the info. RBRT