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Battery Charging Criteria

Battery Charging Criteria

Does anyone know whether the Tesla home chargers can be left charging
for an indefinite period as is the case when using trickle chargers on
normal lead acid batteries ? If not, do the chargers auto disconnect
the supply when the battery is fully charged ?

Thanks.

Rocky_H | 2017年3月13日

Yes, they can be left connected. You're thinking of it backward, though. The connector on the outside of the car is not "forcing" electricity into the car, and you are describing. The connector makes the energy available, but the car decides how much it wants to take and then shuts off when it's done charging.

dbrich | 2017年3月13日

Hi Rocky.
Thanks for that --- a very clear explanation.
Cheers.

jordanrichard | 2017年3月13日

Also, there are no Tesla chargers outside of the car, besides the superchargers. The chargers are built into the car. You can charge your car via a standard household 120v outlet.

Frank99 | 2017年3月13日

Remember - "A plugged in Tesla is a happy Tesla".

Rocky_H | 2017年3月14日

@jordanrichard, It was really obvious what he was referring to. You don't need to do the pedantic correction of terms every time.

Haggy | 2017年3月14日

Yes, it was obvious what he was referring to. It's also clear that many people don't understand the concept of the charger being built into the car, and the car merely needing a mobile connector instead of a more complex external charger. It's not a correction of terms, but helpful information for a potential owner who probably wants to understand how it works.

jordanrichard | 2017年3月15日

Haggy +1.

People come here to learn about Tesla and related things like charging. It is important that people get the terminology correct, otherwise the mis-information ship will keep sailing along.

Rocky_H | 2017年3月15日

@jordanrichard, Quote: “People come here to learn about Tesla and related things like charging. It is important that people get the terminology correct, otherwise the mis-information ship will keep sailing along.”

Well, I suppose, but it’s so common that you do it, too.

“Every car company out there can strike a strategic partnership with Chargepoint, but if the chargers are not fast and more important conveniently located on the highways, it's pointless.”
“Even then, only a fraction of Chargepoint's chargers are Fast chargers.”
https://forums.tesla.com/forum/forums/93-hours-recharge-bolt

“There are countless stories of L2 public chargers not working.”
https://forums.tesla.com/forum/forums/looks-chevy-beat-tesla-punch?page=1

It is like if someone says, “I’m about ready to go. I just need to get my shoes on.”
Do you correct their “mis-information” by telling them that they actually put sandals or boots on instead of shoes?
Or if someone says, “Hang on a sec. I need to get a pen.”
Do you correct their “mis-information” by pointing out that they got a pencil instead?
It’s just using shorthand terms for something to wear on your feet or something to write with or something to charge the car with. If you’re going to a shoe store to buy something, then yes, you need to be specific, but in these types of cases, where the technical term for the equipment doesn’t matter, correcting people’s words like that is just being irritating and serves no helpful purpose, and I’m trying to help you not be that guy.

Anyway, I guess this is my best try at giving this suggestion, so I’ll try not to bring it up to you again if you want to keep doing it.

andy.connor.e | 2017年3月15日

I imagine it does the same that your phone does when its fully charged. My recommendation, dont leave it plugged in when its fully charged. And if you want to go hardcore about it, skip out charging it if you have to leave it plugged in when fully charged, unless you seriously need the charge.

Haggy | 2017年3月16日

When it's fully charged, it's essentially disconnected, from the standpoint of the circuitry. There's no need to unplug it. If a charge is scheduled for the next night and the car went unused, it will simply skip the charge. It won't try to top off a few miles. I'm not sure where the threshold is but it might be about 10 miles from the set level.

SUN 2 DRV | 2017年3月16日

Rocky's explanation of pull vs push was way more helpful to the OP than the pedantic correction of where the "charger" is located.

Frank99 | 2017年3月16日

The whole recommendation to "remove things from the charger when charging is complete" dates back to the first rechargeable batteries in consumer electronics - when manufacturers saved a buck or so by not putting a charging chip in the system, and instead using a "dumb" charger. Leaving the device on the charger would overcharge and destroy the battery. That whole concept got thrown out the window when Lithium Ion batteries started shipping in consumer products - the manufacturer HAS to include the charging chip or the battery catches fire. Any device built in the last 10 years with a Lithium Ion battery has smart charging built in - when the battery is full, charging stops.

One reason to leave the Tesla plugged in is to keep systems up and running - battery temperature management, over-the-air upgrades, etc. Modern Tesla's start shutting down various systems when the car is parked and not plugged in - the longer it isn't plugged in, the more systems get shut down. As long as it's plugged in, all of those background systems can do what they need to do when they need to do it. And you don't have to worry about overcharging the battery - there's probably nobody in the world who knows more about how to coddle Lithium Ion batteries than Tesla, and they're doing all the coddling they know how to do when the car is plugged in.

Mapowing | 2017年3月17日

@Frank99 excellent explanation

bj | 2017年3月18日

@Rocky_H - "Or if someone says, “Hang on a sec. I need to get a pen.” Do you correct their “mis-information” by pointing out that they got a pencil instead?"

Nah, I'd correct them by pointing out that it took 26 seconds not 1!