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I wonder how level 1 vs level 2 charging affects battery life and efficiency. Does the battery take differently to fast vs slow charge in the long run?
 

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To recreate the experiment, I ran the car around town for several days without charging at night (my normal SOP). I made 285.3 miles on 56.2kW (5.1m/kW and the average temp was in the 70’s). The range read 3 miles when I dared go no further. The JuiceBox says it took 59.993 kWh to stuff 56kW into her. To be able to still use ~56.5kW of the 60kW battery seems pretty good.....to me anyway. That’s 94.2%.
You've got your units wrong again. In all of the above cases, kWh are the correct units.

kW and kWh are very different metrics. Please see https://www.mynissanleaf.com/viewtopic.php?p=520169#p520169.
 

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I wonder how level 1 vs level 2 charging affects battery life and efficiency. Does the battery take differently to fast vs slow charge in the long run?
On a Nissan Leaf forum a few years ago someone quoted a battery expert who said L2 provided enough power to burn off something that builds up in the cells that L1 charging could not. Sorry, cannot remember the specific terms used.
 

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[....]
And some interesting surprises

Depth of Discharge (DoD) is critical and can cut battery cycle life by a factor of four if constantly repeated. A model battery may have a 20,000 cycle life discharging 40% regularly and only 5,000 cycles discharging >95%. This condition may be an issue with drivers who adopt a 'gasoline' fueling model: run to near empty then hit the DCFC. Remember, this is not going to happen with one long drive; 5,000 daily cycles is well over 15 years.

I enjoyed the read and hopefully you can add to the forum.
As you say, it is not going to happen over one long drive, but it does beg the question of getting a sense of how much damage is done over just a few discharges >95%. For one thing, that is one method that some here seem to follow in order to get a sense of their own test their own battery capacity.
 

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I'm more paranoid than most when it comes to battery degradation but even I think the occasional discharge to 0% (or thereabouts) or the occasional charge to 100% won't be noticeable.
I think most of the paranoia stems from the days when the LION in our cell phones would degrade down to nothing in 2 years or less.
The biggest cause of that issue was that phones had no BMS AND people would leave them ON overnight while charging. The phones would literally charge 100%, stop, drop to 99% then charge back up to 100% again.. over and over, hundreds, maybe thousands of times overnight.

I'm not saying we've completely solved LION degradation issues, but with BMS to prevent the situation described above, and to regulate charging in other aspects as well, in addition to temperature management systems, and better chemistry, we should be looking at long battery life.
 

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On a Nissan Leaf forum a few years ago someone quoted a battery expert who said L2 provided enough power to burn off something that builds up in the cells that L1 charging could not. Sorry, cannot remember the specific terms used.
It's always been assumed slow charging conventional 12V batteries was better than fast charging, for longer lifetimes.
 

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To recreate the experiment, I ran the car around town for several days without charging at night (my normal SOP). I made 285.3 miles on 56.2kW (5.1m/kW and the average temp was in the 70’s). The range read 3 miles when I dared go no further. The JuiceBox says it took 59.993 kWh to stuff 56kW into her. To be able to still use ~56.5kW of the 60kW battery seems pretty good.....to me anyway. That’s 94.2%.

Armed with the comments in this thread, the paper I still need to read and the data I’ve gathered, I’m willing to put this to bed......for now. I think I’ll try seeing how far down I can take her every quarter or so and see what the long term data tells me. Stay tuned.
If I remember correctly, you could still have something like 10 miles of range left after the GOM stops displaying, which would represent about 2 kWh in your case. You also don't have a SoC figure when you had consumed 56.2 kW, so we don't know how much was left. My guess is you have better than 94% capacity remaining.
 

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A friend of mine has a B-I-L who's an EE and works at the local battery plant (XALT). They've tested and dissassembled a Bolt battery pack. His summary - the pack will last forever.
Michigan? I think the Bolt will rust out before the battery pack goes.
 
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