Tesla powered storage

[eclectricdave]

I charged my car to 90% and left it connected. I need to use my ICE car for a week because of a towing need. Will the car top up in this time? Is there hysteresis? ie does it need to drop SOC before it gets more charge?

 

[raynewman]

I charged my car to 90% and left it connected. I need to use my ICE car for a week because of a towing need. Will the car top up in this time? Is there hysteresis? ie does it need to drop SOC before it gets more charge?

I have found mine doesn't top up - what I do is use the App to 'unlock the charge port'; this will then restart the charge.

 

[animorph]

When your "vampire" losses reach some significant level (a few percent?) it will charge itself again. That could be every day if you have an active data logger running, or every few days if you only lose a mile or two a day.

 

[essmd]

I charged my car to 90% and left it connected. I need to use my ICE car for a week because of a towing need. Will the car top up in this time? Is there hysteresis? ie does it need to drop SOC before it gets more charge?

I am confused... Top Up? as in maintaining to 90% or going to 100%

If you leave the car connected, it will maintain your set charge level literally forever. That is the function of the battery management process and even if you watched it, you would never see a drop.

 

[eclectricdave]

I mean hold 90%

 

[Mark E]

The car will let the charge drop down a little before topping back up to where you set your charging limit.

 

[WhiteStar]

If you're not using your car, why would you want to keep it at 90%?

There's ample evidence & expert advice contained in these forums stating that storing at 50% SOC will minimise cell degradation.

 

[Blue heaven]

If you're not using your car, why would you want to keep it at 90%?

There's ample evidence & expert advice contained in these forums stating that storing at 50% SOC will minimise cell degradation.

I agree with Whitestar, set it to 50 or 60% when not in use, a few hours before you need it for a long trip get out your phone/iPad app and set the car charge up to 80 or 90%.

 

[essmd]

If you're not using your car, why would you want to keep it at 90%?

There's ample evidence & expert advice contained in these forums stating that storing at 50% SOC will minimise cell degradation.

I do agree with this, and have heard many times that unless range is needed, the lower you keep your charge level the better for the battery.

However, I also intuitively thought about the concept of the numbers of recharging cycles as being somewhat impacting long-term battery health, therefore minimizing cycles by charging to a higher level, then only charging when around 20% would be beneficial. However, this goes against what Tesla recommends, so I yield to their expertise and knowledge of their batteries and charging system.

Also, apparently keeping plugged in helps to "move the charge" around the almost 8000 18650 batteries... what a task...

 

[eclectricdave]

I havent explained everything. Where I keep the car is on a country property outside Melb. It is powered by a 5kW inverter & 5kW PV array.with batteries. This time of year electricity production is low. Also there is no internet. I usually charge to 100% before leaving because my Melb house is also solar powered with less PV than country house. I will want to leave the next day when I do the car changeover. The RichSC is out of the way.

 

[essmd]

Ahh, then you have a less common charging situation than most.

So keeping your car plugged in when not in use is still the best process, as the "trickle" charging to maintain should be within the power availability.
However, if your concern is for times when the required power to charge is not available, I am not sure how the adapter deals with that, but pretty sure this was part of the design, just like when during a blackout.