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Hmm... So is there any taper if charging at 240VAC, 11kW, or does it pull that all the way to 100%. And if so, is that higher than the ending taper rate on a DCFC?
240V at 32A is less than 8kW of power, so there isn't really any "taper" other than the battery balancing step (which uses less power) once the battery has reached full charge.
 

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2022 models will support 11kW AC charging with identical battery as 2020-2021 models. Why? Competition? Or maybe inverter manufacturers are phasing out 32A inverters in favor of higher powered units?

If the batteries can take 55kW on DCFC, certainly 11kW is not going to stress things. Once the power leaves the inverter, it is DC current. So to the batteries, it all looks the same whether it is AC or DC charging, just a different path to get there.
Would be neat if we can buy the higher power OBC and get it installed at the dealer. The dealership would probably appreciate the work. :)
 

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Discussion Starter #23
This also explains why when Tesla Powerwall is in use, it will disable the solar panel until battery SOC reaches 60%. However, as a home battery, that's a bad idea because when your Powerwall shuts off the solar at noon and drains itself, you will have no power that night. LOL
The better solar systems usually have a red light diode that prevents back drain.
But the red dot goes out after awhile that leaves you guessing if the drain protection is still working or not. Sure the better systems work fine but you may never recoup the expense.
Some care less about costs, but unfortunately, that is not me.
 

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Would be neat if we can buy the higher power OBC and get it installed at the dealer. The dealership would probably appreciate the work. :)
I wouldn’t bother, most of us wouldn’t bother.

Following my 130 mi commute, I plug in and the schedule starts charging at 10pm. By 1-2am, I have restored everything I used the day before and continue sleeping for several hours.

The number of times in 3 years that faster L2 would be helpful, twice. And both times, the public charger was 6-7kW so it wouldn’t have helped.

Now, faster DCFC, different discussion. But 2022 doesn’t seem to have any improvements to DCFC.


Sent from my iPhone using Tapatalk
 

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True, as long as you keep in mind that 11kW at a 50% state of charge is a lot different in terms of battery stress than 11kW at a 90% state of charge.
If 11kW is a problem at 90%, surely they BMS would start to taper on L2 also. I have not charged beyond HTR (88%) in a long time, but I suspect 32A L2 slows a bit at higher SOC.
 

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If 11kW is a problem at 90%, surely they BMS would start to taper on L2 also. I have not charged beyond HTR (88%) in a long time, but I suspect 32A L2 slows a bit at higher SOC.
L2 doesn't get to 11kW, it doesn't even get to 8kW. 240V times 32A = 7,680W (7.68kW). So it doesn't have to slow the L2 charging rate when the battery fills up, although my understanding is that the power draw does drop when it performs cell balancing.
 

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L2 doesn't get to 11kW, it doesn't even get to 8kW. 240V times 32A = 7,680W (7.68kW). So it doesn't have to slow the L2 charging rate when the battery fills up, although my understanding is that the power draw does drop when it performs cell balancing.
2022 models will, that was the context of the point (from my prior post).
 

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Hmm... So is there any taper if charging at 240VAC, 11kW, or does it pull that all the way to 100%. And if so, is that higher than the ending taper rate on a DCFC?
There almost certainly will be a taper because there is one now at 7.5kW if you charge to 100%.
 

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This also explains why when Tesla Powerwall is in use, it will disable the solar panel until battery SOC reaches 60%. However, as a home battery, that's a bad idea because when your Powerwall shuts off the solar at noon and drains itself, you will have no power that night. LOL
Do you have a source for this claim? I've had Powerwalls for a couple of years and have never seen this behavior during tests, nor have I read of such a thing.

The only time that the TEG instructs the solar to shut down is in a grid fail condition, the Powerwalls are FULL, and the Sun is shining. The PV is shut down because the energy has nowhere to go. Once the home load draws the 'Walls down a few percent, the PV is turned back on. The draw-down is nowhere near 60%. It's in the 90s.
 

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Discussion Starter #31
The Bolt is designed so that the battery can charge with up to 50kW of power or more at the low end and around 10kW of power when it's nearly full.

120V/8A charging delivers less than 1kW of power, and 120V/12A delivers less than 1.5kW of power. Both of those are way, way less than the battery and its charging system were designed to handle, even for a full battery. So it's hard for me to believe that there would be any noticeable difference between these as far as battery longevity goes.

I charge my battery using the OEM EVSE at 240V / 12A, which delivers less than 3kW of power, and IMHO the same comments apply.

An L2 EVSE running at the car's limit of 240V / 32A delivers less than 8kW of power, still less than the design point of the charging system. You need to use a DC Fast Charger before the charger's capability to deliver power exceeds what the car designers felt was acceptable, which for a battery that's nearly fully charged seems to be around 10kW. So L2 charging is getting closer to the battery's design limits when the battery is nearly full (but not when it's around 80% or less).

The big question is this: why you think that the car's designers chose that 10kW limit? Did they choose it because they were conservative and they felt that it was a safe level that didn't impact battery life significantly, or did they choose it because they wanted to push the battery technology as hard as they felt comfortable with in order to deliver faster charging times?

If you believe the former, you shouldn't have any issues with full L2 or DC Fast charging. If you're very conservative and you want to do everything in your power to avoid stressing your battery even if it means longer charging times and potential inconvenience, then you might want to back off on those highest charging rates and avoid filling the battery completely unless you really need to.

Some folks with very high mileage and a history of using a lot of DC fast charging have reported pretty minimal battery degradation, which encourages us to believe that GM was pretty conservative with the design of its charging system.

Even so, because the Bolt has a lot of capacity and therefore a lot of range - more range than most of us need on a daily basis - limiting the maximum charge of the battery in normal use is a pretty common practice. It's easy to do, has minimal impact on your daily life, and is more likely to help the battery than hurt it. And it doesn't stop you from deciding to fully charge using a fast charger on those occasions when it makes your trip faster or more convenient.
Thanks for a thorough, comprehensive answer. Will be interesting to see "long range 300k mi+" effect on different charging strategies down the road.
 

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Do you have a source for this claim? I've had Powerwalls for a couple of years and have never seen this behavior during tests, nor have I read of such a thing.

The only time that the TEG instructs the solar to shut down is in a grid fail condition, the Powerwalls are FULL, and the Sun is shining. The PV is shut down because the energy has nowhere to go. Once the home load draws the 'Walls down a few percent, the PV is turned back on. The draw-down is nowhere near 60%. It's in the 90s.
8:00, so this guy is wrong?


and this owner & Tesla Support are wrong?

 

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8:00, so this guy is wrong?


and this owner & Tesla Support are wrong?

Yes, and yes.

Enphase is trying to sell their batteries, and the Tesla poster (and Customer Service) was operating on firmware that's at least two and a half years old.
 

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Yes, and yes.

Enphase is trying to sell their batteries, and the Tesla poster (and Customer Service) was operating on firmware that's at least two and a half years old.
The guy sells all kinds of systems, not just Enphase. His Youtube channel has tons of comparisons.

Good to know the bug was fixed. I know it probably made sense to the engineers on system design side but was not very functional.
 

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I believe that I read tests that indicate the Bolt won't engage under 8A.
I charge my 2019 LT at 6A, L2 frequently, not because I want to baby the battery, but because my utility appreciates low peak loads and sometimes that's all my solar panels can muster.
 

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I charge my battery using the OEM EVSE at 240V / 12A, which delivers less than 3kW of power, and IMHO the same comments apply.
Can you elaborate on your OEM at 240V setup? Are you using a 120V-to-240V dongle? If so, can you recommend one? I've seen that the OEM EVSE is 240V capable (made by Clipper Creek), and it's best to have a certified electrician set it up for 240V charging (NEMA connector from the panel) with a dongle to step up to 240V.

Thank you!
 

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Can you elaborate on your OEM at 240V setup? Are you using a 120V-to-240V dongle?
Better sit down - I've installed a NEMA 5-15 socket in my garage that's connected to a 240V circuit breaker. Yep, it's against code and a nuclear-level hazard, but it was the simplest way for me to do it and it leaves the thermistor in the NEMA 5-15 cord fully functional to cut power if it detects the plug overheating (which means the socket is overheating).
 

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Better sit down - I've installed a NEMA 5-15 socket in my garage that's connected to a 240V circuit breaker. Yep, it's against code and a nuclear-level hazard, but it was the simplest way for me to do it and it leaves the thermistor in the NEMA 5-15 cord fully functional to cut power if it detects the plug overheating (which means the socket is overheating).
That was quick, Sean. Thank you.

It sounds like the NEMA 5-15 is a female socket that accepts the OEM EVSE 3-prong male connector and is wired to 240V at the panel; no dongle? If correct, I get it. I've read on a Volt owner's site (sourced from this site) about having an electrician make the dongle to step up to 240V, matching it to whatever NEMA connector will be used on the female end.

[I'm looking at the 5 yo thread you participated in here: 2016 Volt 120v EVSE is L1/L2 Conversion Capable]
 

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Better sit down - I've installed a NEMA 5-15 socket in my garage that's connected to a 240V circuit breaker. Yep, it's against code and a nuclear-level hazard, but it was the simplest way for me to do it and it leaves the thermistor in the NEMA 5-15 cord fully functional to cut power if it detects the plug overheating (which means the socket is overheating).
At least change the outlet cover to red and put a printed sticker on it saying "250V - EV Charger Only" or something like that.
 
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Can't seem to find via search, so here it goes.

Is L1 8amp charging easier on the battery than 12amp?
Same question on L1 vs L2/L3.
In my case, I can get by with the slowest trickle charging if it is the best option for battery life. Actually wish there was about a 4amp trickle charger available if that would extend battery retention even further.
(Keep my ICE generator 12v battery on a 0.5amp maintainer and may do same with Bolt 12v. Chevy smartly has the smaller adjacent posts available for just that).
And is 8 amp safer than 12 for old wiring/sockets?
 
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