Where are the new 60 and 70 cars SW limited?

[Olle]

There has been extensive threads about these software limited batteries describing their usable kWh but some interesting questions remain unanswered:
1. is the limitation on the top or bottom of the charge? If it is split between top and bottom, how?
2. what happens when you hit 0 miles?

What would be cool about this information is that we would have a better understanding of how much 100% charge wears on the battery (i.e. how close you are to the real 100%) and how careful you need to be not to run below 0. On the old 85s I remember that it was pretty arbitrary where the car stopped but you could more often than not drive into negative miles before they hit the bricking reserve and shut down.

 

[BerTX]

I think if somebody had a concrete answer, they would have said so i all those discussions that you already read.

Each person has to look at the clues that we have available and decide what they believe. There are folks here who are pretty darn sure, and willing to bet your car battery health on it.

The question is, are you?

I charge to 80% unless I need more (for me, that basically means if I'm going to use the car, I'll charge to 100%). In the past, I've Supercharged to 100%, but I'm weaning myself off of that. I had one time that the Supercharger was DOA when I got there. Since I had charged to 100% at the previous SC, I was able to limp to the next one down the road.

 

[Olle]

Thanks for that answer.
Another question came to mind. There are a lot of experts who say you need 100% charge once in a while to balance the battery. If the limitation is on top and the battery will never be full, how would it ever get balanced?

 

[mblakele]

I believe the 60 and 70 are top-limited, based on reports of reduced charging taper and full regen at high SoC. Whether that's right or not, what happens around zero will be unpredictable because the SoC the car reports is just an estimate.

Assuming it's top-limited, the cells may get unbalanced. But would that affect anything? I suspect not. If and when you ever unlocked the full capacity, you could give it a full charge then.

 

[Olle]

There is definitely a top limit, that makes sense. But low charging taper and full regen could be achieved even if only part on the limit would be on top.

Since the battery wears most in the extreme ends, http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

it would make more sense to limit on both ends for longevity purposes, no?

 

[DB 2]

Top: 86% of non-limited capacity.

Bottom: ~5.5% (~3.8 kWh remaining per BMS).

The bottom is available for driving (no arbitrary cutoff) all the way to 0 kWh remaining, but be careful because the 0 kWh point is an estimate and can be off in either direction.

Based on personal experience with refreshed S60.

 

[Olle]

Top: 86% of non-limited capacity.

Bottom: ~5.5% (~3.8 kWh remaining per BMS).

The bottom is available for driving (no arbitrary cutoff) all the way to 0 kWh remaining, but be careful because the 0 kWh point is an estimate and can be off in either direction.

Based on personal experience with refreshed S60.

Finally somebody with experience with the interesting part of this How do you mean that the bottom is available for driving, and how far below 0 miles did you drive before you hit 0 kWh remaining? (0 plus anti bricking reserve obiously)

 

[DB 2]

How do you mean that the bottom is available for driving, and how far below 0 miles did you drive before you hit 0 kWh remaining?

I'm not sure what you mean? You just keep driving. The IC gauge stays on zero (no negative SOC or rated miles). I have driven for 3.5 kWh below zero repeatedly. Miles depends on conditions, but is usually between 13 and 18. I have always put the car in the garage under its own power.

 

[Shock-On-T]

There has been extensive threads about these software limited batteries describing their usable kWh but some interesting questions remain unanswered:
1. is the limitation on the top or bottom of the charge? If it is split between top and bottom, how?
2. what happens when you hit 0 miles?

What would be cool about this information is that we would have a better understanding of how much 100% charge wears on the battery (i.e. how close you are to the real 100%) and how careful you need to be not to run below 0. On the old 85s I remember that it was pretty arbitrary where the car stopped but you could more often than not drive into negative miles before they hit the bricking reserve and shut down.

Fremont, I believe.