Danger/long term issue if battery goes flat?

[Midnight Man]

Hi folks, a quick question for those who may be able to advise please

My MY RWD is in for hail damage repair, and as part of that process, the boot and doors are being left open for extended periods for paint-drying purposes.

This doesn't allow the car to go to "sleep", rather, it's "idling" a lot, and therefore, the battery is losing charge.

What happens if the battery falls to a low percentage? Does the "idling" stop and the car shut down? If it falls to 0%, and potentially stays there for a period (week or two), will this harm the battery?

Many thanks for any advice here!

 

[meloccom]

Generally if a battery goes below 20% for a long period of time you can expect some acceleration of degradation.
If it goes below about 10%, I would call the repairer and ask them to put it on charge overnight.

 

[Vostok]

If Sentry and Climate are both off, the car not sleeping should not consume too much battery. How much is it losing per day? Also, I understand that parked Teslas will progressively shut down various systems to preserve the traction battery if the SoC goes very low. Finally, Teslas have a power reserve. When the battery reports SoC of 0%, it’s not actually at 0%.

From what I’ve read, it is worse for a Li-Ion battery to be on 0% SoC for an extended period of time than it is for it to be on 100% for the same amount of time. As to how long an “extended period” is, people have various views, but it seems to range from a couple of weeks to a couple of months.

 

[E90alex]

Why have they not disconnected the LV battery?

 

[doggy1]

Why have they not disconnected the LV battery?

Perhaps ICE mentality?

A cautionary tale. My Zoe's charger failed in the middle of Covid and it took the dealer 3 months to fix. Even though I asked them to disconnect the HV battery, they did not. Started at 15% and ended up very low. I lost 2.5% SOH due to that.

I would get your repairer to disconnect the HV battery. Not hard- many of us have done it on our own cars.

 

[Midnight Man]

Thanks for all the replies - I assume if the battery is disconnected, the car will go "offline"?

 

[Quickst]

My MY RWD is in for hail damage repair

1) switch off sentry
2) stop checking on the car
3) ask the repair shop to charge the car
4) Disconnecting the LV battery would help - disconnecting the LV battery will mean the car will go offline and opens the HV contactors

I would get your repairer to disconnect the HV battery. Not hard- many of us have done it on our own cars.

Should not need to
Disconnecting the LV battery should open the HV contactors which isolates the HV battery from the components which use the HV side of the system.
If wanting to service the HV side, need to do a Vehicle Electrical Isolation procedure to confirm the positive and negative contactors are in the open state in case for some reason they are stuck on the closed position.