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PowerWalls not charging to 100%

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I recently received PTO for my solar panel system. I am using “Backup” mode. On the first day of activity my 3 PW’s charged to 98%. They are slowly losing charge each day and are now down to 96%. Once they got to 98% all solar energy was directed to the home or the grid. Is this normal behavior? I expected them to charge to 100% and stay there until needed. Will they discharge to a certain level and then charge back up to 98%? Thanks.
 
OP, if you want to see them charge to 100% (just to see it, for example) change to self powered and set the reserve to something like 90%. If the powerwalls are in self powered mode, they will definitely charge to 100%. In backup only mode, they dont, as mentioned by @nyprepper .
 
FWIW I run mine mostly in Advanced - Cost Savings. Rarely did I ever see it charge past 99%. Today it has charged to 100%. On FW 20.40.3

Screenshot_20201231-135713_Tesla_sm.jpg
 
Even though 100% is not truly 100%, the higher the SOC that you leave it just sitting there, the faster your PWs will degrade.
Is there any evidence to back up this claim as it applies to PW batteries? Or, more specifically, to document how much excess degradation you would see? I have not seen anything that suggests any significant difference, and, with full net metering and no TOU rates, I would see no reason to try and maintain a lower charge when the main result would be less backup power in the event of an outage. And, since Tesla doesn't let you fix the percentage (as in, I always want to be at exactly 80%,) modes that allow you to go to a lower number result in more charging and discharging, which also means more wasted energy.
 
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