Optimal EV Charging

What would be great to see is chargers in highway rest stops, look out points, tourism info centers, and fast food restaurants.
Eating some mcnuggets, and taking a pee, while the car charges would be fabulous.
Or going for a walk somewhere beautiful along the side of the highway.
 
What would be great to see is chargers in highway rest stops, look out points, tourism info centers, and fast food restaurants.
Eating some mcnuggets, and taking a pee, while the car charges would be fabulous.
Or going for a walk somewhere beautiful along the side of the highway.
There’s a number of fast food restaurants here that have them. I know I’ve seen more than one at a Culver’s. Tesla Supercharger too. It’s my stopping point on my 150 mile return trip regardless of what car I’m in.
 
For reference, I’ve read that whether you charge at 10, 20, 32 or 48 amps at 240v, it really makes no difference to the battery as it’s basically like a trickle charge when comparing to a Tesla Supercharger. I’ve alternated between 24 and 32 at home for no real reason as either one gets back my 55-60 mile daily commute in a few hours.

Interesting video though.
 
I'm still using a NEMA 14-50 receptacle on a dedicated 40A 220 Volt circuit. Works fine for me especially as I'm now charging at only 25A/hr. [Which is plenty fast enough for my usage.]

Using the Tesla charge cable with a Tesla 14-50 adapter works just fine. I think that's what you used to use too. What advantage was there to adding the Tesla Wall Charger?
Yes, I used the Mobile Charger for 5 years. The Wall Charger is hard wired; no plug. What you are doing is fine. I am long term Tesla and will very well have 2 later this year. I now keep the Mobile in the frunk with 3 plugs: 110v, 240 3 prong dryer and Nema 14-50.

You can add another Wall Charger on the same circuit and they will share the power. Of course this is not for the average user.
 
For reference, I’ve read that whether you charge at 10, 20, 32 or 48 amps at 240v, it really makes no difference to the battery as it’s basically like a trickle charge when comparing to a Tesla Supercharger. I’ve alternated between 24 and 32 at home for no real reason as either one gets back my 55-60 mile daily commute in a few hours.

Interesting video though.
The Mobile Charger is just the cord; it uses the car's internal charger. Superchargers are chargers that bypass the car's charger.
 
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The Mobile Charger is just the cord; it uses the car's internal charger. Superchargers are chargers that bypass the car's charger.
Yep, I get that. I just meant that any of the at-home methods are the equivalent of peeing in the ocean when compared to Supercharging.
 
Yep, I get that. I just meant that any of the at-home methods are the equivalent of peeing in the ocean when compared to Supercharging.
I think reason some lower it is just to space out charging for their use because of the always be charging mantra some swear by. I can't fault the thought process. It's hard to forget to charge the car that you always leave plugged in.
 
For reference, I’ve read that whether you charge at 10, 20, 32 or 48 amps at 240v, it really makes no difference to the battery as it’s basically like a trickle charge

That is generally true a 48A (11,500W) charge rate is still a fractional C rate for just about any modern 80,000KWh pack. 1/6th to 1/7th C.
 
For reference, I’ve read that whether you charge at 10, 20, 32 or 48 amps at 240v, it really makes no difference to the battery as it’s basically like a trickle charge when comparing to a Tesla Supercharger. I’ve alternated between 24 and 32 at home for no real reason as either one gets back my 55-60 mile daily commute in a few hours.

Interesting video though.
At 40 amps my GT turns on the cooling system to regulate temps in the summer a lot. With 24 amp, little to no need. Also, laser temps of handle to car, and charger to wallplug show about a 20 to 30 degree delta. Im hsing a Hubbell plug, so I know its not poor components.
 
I think reason some lower it is just to space out charging for their use because of the always be charging mantra some swear by. I can't fault the thought process. It's hard to forget to charge the car that you always leave plugged in.
In the winter, if keeps the juice flowing nearly until im ready to leave again. Battery stays a bit warmer in my detached garage.
 
I think reason some lower it is just to space out charging for their use because of the always be charging mantra some swear by. I can't fault the thought process. It's hard to forget to charge the car that you always leave plugged in.

Why not just time it? Charging the battery is always going to be big power drain, but there are these little things like keeping the computer running and heating/cooling where it’s better to not use the battery. If someone had to wait outdoors with the heat on in an EV, I’d think it would be better to draw that from external power than from a battery. Especially since battery performance/efficiency goes down with lower temps but external power efficiency is generally independent of temperature.
 
I think it’s a little more complicated than a pass through. At least a relay and thermal protection to cut off power if it senses a fault.
EVSE(Electric Vehicle Supply Equipment) is the term. All it does is supply power to the car. Sure there's circuitry to cut power in a fault(hopefully), but all it's doing otherwise is giving power to the onboard charger.
 
For reference, I’ve read that whether you charge at 10, 20, 32 or 48 amps at 240v, it really makes no difference to the battery as it’s basically like a trickle charge when comparing to a Tesla Supercharger. I’ve alternated between 24 and 32 at home for no real reason as either one gets back my 55-60 mile daily commute in a few hours.

Interesting video though.

Any Level 1 or 2 charging is going to be well within a vehicle’s ability to cool down the battery.

Level 3 is another matter. Tesla has to liquid cool the cables on Sulerchargers. Not sure why the 72kW Superchargers have the same cable thickness, other than maybe it simplifies repair parts.
 
EVSE(Electric Vehicle Supply Equipment) is the term. All it does is supply power to the car. Sure there's circuitry to cut power in a fault(hopefully), but all it's doing otherwise is giving power to the onboard charger.

I at least hear an audible click of the relays within the box when the car indicates it’s starting to accept power or when there’s a user controlled disconnection. If I stop charging, the relays seem to disconnect but a Model 3 indicates it’s receiving 2V.
 
Why not just time it? Charging the battery is always going to be big power drain, but there are these little things like keeping the computer running and heating/cooling where it’s better to not use the battery. If someone had to wait outdoors with the heat on in an EV, I’d think it would be better to draw that from external power than from a battery. Especially since battery performance/efficiency goes down with lower temps but external power efficiency is generally independent of temperature.
That involves more thought. I just don't bother worrying about it much. I could set a limit and just keep it plugged in but considering that the LFP has such a narrow voltage range I like to occasionally let it drop down and Tesla says to charge it to 100% once a week. It's the only way I'll accomplish that for battery management anyway. Sure it only seems to use the power supply to warm up when it's plugged in and if I have a longer trip to make then I worry about it. Most days the car doesn't see more than 10 miles so I don't worry about it. I'm only using 120V right now so everything is a trickle.

I have all the temperature protections shut off. I'd worry about turning those on if it was sitting out in the elements when it's cold, but the car heats up quick enough that I just don't concern myself with it and and it's been especially mild this year.

When I start daily driving it in a few years my tactics will definitely change. I'll use the battery limiter and then allow it to get to 100% on 240V when I get called to work. It's the right battery to deal with my style of abuse moreso than the ones that say to limit charging to 80%. If I do that I'd get roughly the same range as the one charged to 80%. That's a better fit for my wife's usage. She really wants a Model X so I'll likely buy one of those used in a few years and drive our current car daily.
 
That involves more thought. I just don't bother worrying about it much. I could set a limit and just keep it plugged in but considering that the LFP has such a narrow voltage range I like to occasionally let it drop down and Tesla says to charge it to 100% once a week. It's the only way I'll accomplish that for battery management anyway. Sure it only seems to use the power supply to warm up when it's plugged in and if I have a longer trip to make then I worry about it. Most days the car doesn't see more than 10 miles so I don't worry about it. I'm only using 120V right now so everything is a trickle.

I have all the temperature protections shut off. I'd worry about turning those on if it was sitting out in the elements when it's cold, but the car heats up quick enough that I just don't concern myself with it and and it's been especially mild this year.

When I start daily driving it in a few years my tactics will definitely change. I'll use the battery limiter and then allow it to get to 100% on 240V when I get called to work. It's the right battery to deal with my style of abuse moreso than the ones that say to limit charging to 80%. If I do that I'd get roughly the same range as the one charged to 80%. That's a better fit for my wife's usage. She really wants a Model X so I'll likely buy one of those used in a few years and drive our current car daily.

I’m thinking it’s providing 2V from a transformer in the box when it’s not actively charging. I can hear the relays open, but I’d think turning 2V on/off can be done with ICs.
 
I’m thinking it’s providing 2V from a transformer in the box when it’s not actively charging. I can hear the relays open, but I’d think turning 2V on/off can be done with ICs.
I'll have to check next time when I have scheduled charging on. I typically only let it charge after 8pm anyway, so there is a decent amount of time that it is plugged in but not charging.
 
I'll have to check next time when I have scheduled charging on. I typically only let it charge after 8pm anyway, so there is a decent amount of time that it is plugged in but not charging.

Educated guess on my part. When hitting “stop charging” on the screen or Tesla app, there’s a noticeable click coming from the Mobile Connector box and the screen then displays 0A and 2V.
 
At 40 amps my GT turns on the cooling system to regulate temps in the summer a lot. With 24 amp, little to no need. Also, laser temps of handle to car, and charger to wallplug show about a 20 to 30 degree delta. I'm using a Hubbell plug, so I know its not poor components.
That's interesting. Possible the temp rise is still minor, but over the temp threshold due to high initial temperatures.

Since the heating is really due to internal resistance, and charging at 1/7th the C rate is pretty gentle, I'd expect only a minor rise. Can you display the battery temp before and during charging?

There are optimum charge temps for each charge rate too. Generally, the faster the charge, the higher the ideal temperature to avoid damage.
 
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