Trickle charge deeper than fast charge?

[BoHoWo]

We have visited our son already three times with our 2023 Tesla Y LR (that is the same six one-way trips). One one-way trip costs 19-20%. Last Memorial Day weekend we spent a couple of nights there and did quite some local driving. Two days before going home I decided to use his 15A/110V outlet to charge back to 80%. That trickle charge took more than 36 hours. Lo and behold, having arrived home our Tesla Y had used only 15-16% of the battery charge. That results in a significantly lower mileage (mi/kWh)!
Question: does a slow trickle charge provide a “deeper” charge than my “fast” charge at my 60A/220V Tesla charging pole? [note: I have 5 times 19-20%, and one time 15-16%]

 

[ATPMSD]

15A/120V is not a trickle charge, so I am unsure of your question. There are many variables that can explain the difference you saw. Here are a few:

• Temperature
• Wind
• Changes in elevation
• Your average speed
• Usage of Sentry
• Overheat protection
• How long the car sat asleep (from what you said this seems the most likely. If your car sat at your son's house the 5-times you saw the 19-20% usage, remember the car consumes power when just sitting there).

 

[Park2670]

I drive 400 miles each way pretty regularly to visit family. The occasional time the wind pushes us home, our efficiency drops from ~300wh/mi to 260wh/mi. Made it so I could skip a supercharger.

Using the 120v plug does nothing to how much energy the car can accept or hold. All it does is take longer to charge.

 

[spsheridan]

... That trickle charge took more than 36 hours. Lo and behold, having arrived home our Tesla Y had used only 15-16% of the battery charge. That results in a significantly lower mileage (mi/kWh)!

I'm not sure what you're saying here. If the "trickle charge" resulted in a lower drain on your battery for the same trip (15-16% vs. 19-20%), wouldn't that reflect higher mileage in mi/kWh?

 

[BoHoWo]

I'm not sure what you're saying here. If the "trickle charge" resulted in a lower drain on your battery for the same trip (15-16% vs. 19-20%), wouldn't that reflect higher mileage in mi/kWh?

I am sorry … you are correct, more miles per kWh (fewer kWh’s per 100 miles).

 

[jjrandorin]

Question: does a slow trickle charge provide a “deeper” charge than my “fast” charge at my 60A/220V Tesla charging pole? [note: I have 5 times 19-20%, and one time 15-16%]

No, it doesnt.

Any difference is going to be due to something else, and there are a LOT of "something else's" it can be. Tire wear, wind, overall outside temperature, etc etc etc.