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Discussion Starter #1
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).
 

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I am not a battery expert, nor did I sleep in a Holiday Inn Express last night. Nevertheless, I have a hard time imagining that anyone could notice a real world difference in battery life between charging at 120V x 8A vs 120V x 12A. You're much more likely to see an impact from your driving habits, local weather conditions, frequent fast charging, leaving the battery charged at 100% for extended periods, etc.
 

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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?
No. The power difference there is irrelevant.
Same question on L1 vs L2
No. The power difference is irrelevant
(L1 vs) L3.
There is no L3. Officially SAE has DCFC Level 1 and DCFC Level 2, which the Bolt (and I believe every other EV with CCS1/CCS2) only implements DCFC Level 2. Common terminology is CCS or DCFC. Level 3 is deprecated.

Answer is still no with the Bolt.
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).
Not possible. Minimum J1772 current level is 6A. I believe that I read tests that indicate the Bolt won't engage under 8A.

The two primary wear effects on Lithium batteries are State of Charge extremes, and time. All charging on the Bolt measures under 1C charging rate, which is low enough to have no impact on the battery. Once could charge every day with DCFC with minimal battery wear.

Set your max SOC to 80%. Never run it down to 0% SOC and keep it there. Charge anyway you want. Everything will be fine.

ga2500ev
 

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Is L1 8amp charging easier on the battery than 12amp?
The single largest determinant of how much capacity you will have at 100K miles, or 8 years, is the capacity it left the factory with. There has been significant variation right from the factory. Beyond that, the biggest effect is age. You will lose capacity every year, regardless of what you do. Any charging rituals you devise will do more for your health than the battery's. ;)

I assume, since you are concerned about battery health, that you have already set up Torque Pro, and know your current Ah capacity?
 

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Discussion Starter #5
I am not a battery expert, nor did I sleep in a Holiday Inn Express last night. Nevertheless, I have a hard time imagining that anyone could notice a real world difference in battery life between charging at 120V x 8A vs 120V x 12A. You're much more likely to see an impact from your driving habits, local weather conditions, frequent fast charging, leaving the battery charged at 100% for extended periods, etc.
Just to be clear, I was trying to express effect on battery longevity and not range. Although your appreciated answer can actually apply to both.
I know from my tournament bass fishing days, that trickle charging the trolling motor batteries seem to extend battery life considerably over hard charging. Then again different era, different technology.
 

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Discussion Starter #7
The single largest determinant of how much capacity you will have at 100K miles, or 8 years, is the capacity it left the factory with. There has been significant variation right from the factory. Beyond that, the biggest effect is age. You will lose capacity every year, regardless of what you do. Any charging rituals you devise will do more for your health than the battery's. ;)

I assume, since you are concerned about battery health, that you have already set up Torque Pro, and know your current Ah capacity?
Thanks, there goes my low amp solar charging theory.
Actually haven't done the Torque Pro yet. May be testing the outer cognitive limits of this 75 year old, (Joe, I can relate) but if taxed, I can always secure the services of my 4th grade neighbor.
 

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Discussion Starter #8
Yes. If you put lithium ion batteries on a trickle charger to keep them "topped up" at 4.2 volts per cell, they will be junk in half the time. Ask people who always keep their phones plugged in.
So am I wrong to keep my laptop (now called desktop, so what do you now call the old desktop?) constantly plugged in?
 

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Thanks, there goes my low amp solar charging theory.
Actually haven't done the Torque Pro yet. May be testing the outer cognitive limits of this 75 year old, (Joe, I can relate) but if taxed, I can always secure the services of my 4th grade neighbor.
Absolutely understand the cognitive concerns. I break out in a cold sweat every time my PC says," Do you want to download this update?" I got my first smartphone to see Torque Pro on the Bolt.
 

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So am I wrong to keep my laptop (now called desktop, so what do you now call the old desktop?) constantly plugged in?
Yes. If you have a device with lithium ion batteries, and it has a dumb charger, which can't be set to less than 4.2 volts per cell, you are killing the battery life.
 

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Thanks, there goes my low amp solar charging theory.
Slow charging the Bolt will not hurt it. You have the ability to set the finish charge level in 5% increments. If you have the luxury of only driving 50 miles every day. You can set the charge level to 60%, and run it down to 40% every day, and you will, in theory, see the longest possible battery life.
 

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Is L1 8amp charging easier on the battery than 12amp?
That amp setting is not for the car's battery, it's really for your home and the safety of old wiring and sockets drawing that much continuous power. That's why the granny cable monitors the temperature of the outlet it is plugged into.
 

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Discussion Starter #13
Slow charging the Bolt will not hurt it. You have the ability to set the finish charge level in 5% increments. If you have the luxury of only driving 50 miles every day. You can set the charge level to 60%, and run it down to 40% every day, and you will, in theory, see the longest possible battery life.
On my 2020 you have four 25% increments which you have to guestimate from. I could be missing something.
 

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Yes. If you put lithium ion batteries on a trickle charger to keep them "topped up" at 4.2 volts per cell, they will be junk in half the time. Ask people who always keep their phones plugged in.
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
 

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Is L1 8amp charging easier on the battery than 12amp?
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.
 

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The big question is this: why you think that the car's designers chose that 10kW limit?
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.
 

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If the batteries can take 55kW on DCFC, certainly 11kW is not going to stress things.
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.
 

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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.
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?
 
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