How harmful is low SOC?

[PDB33]

Model S 2017 75D BTX8 battery has been at a Tesla-approved body repair centre for repair of a couple of dents for a week. Yesterday I received a notification on my phone that SOC was 7%. I don't know long it is been this low. This morning it was 4%. They plugged it into a domestic supply at 2kW and brought the charge up to 8% with a plan to move it to a fast AC charger overnight.

Have they been killing my battery?

 

[ewoodrick]

Don't worry about it. The car will completely shut down before significant harm is done.
Of course delivering it with a full charge wouldn't have been a bad idea.

 

[Glan gluaisne]

I strongly suspect that when the car reports 0% the battery probably has some remaining capacity, as it seems pretty normal to have a buffer at the top and bottom of the battery range. If I had to guess I'd say that an indicated 0% might really be around 5% and an indicated 100% might really be about 95%.

Bjorn did a test on a Model 3 recently where he drove it around until it shut down, and there seemed to be a fair bit of range left below an indicated 0%, and I suspect that the car shut down before the battery got to a real 0% SoC.

 

[Jason71]

I think it's one of those things you would not want to do repeatedly like holding at 100% for long periods but once will not do any noticible harm. Tesla have moved on at least a bit since the roadster!

 

[Yev000]

Battery will be fine. below 20 some features don't work, like sentry.

The biggest risk taking it to 0 is killing the 12v battery.

From the manual:
"When left idle and unplugged, your
vehicle periodically uses energy from the
Battery for system tests and recharging the
12V battery when necessary."

"If you allow the Battery to discharge to
0%, other components may become damaged
or require replacement (for example, the 12V
battery)."

"Discharging the Battery to 0% may result in
damage to vehicle components. To protect
against a complete discharge, Model 3 enters
a low-power consumption mode when the
displayed charge level drops to approximately
0%. In this mode, the Battery stops supporting
the onboard electronics and auxiliary 12V
battery. Once this low-power consumption
mode is active, immediately plug in Model 3 to
prevent a jump-start and 12V battery
replacement.

Note: If the vehicle is unresponsive and will
not unlock, open, or charge, then the 12V
battery may have become discharged. In this
situation, contact Tesla."