I honestly do not know the correct answer for you. I do know with zero lemon, Hyperion, etc...those 7000 mah batteries should never be discharged to zero. If memory serves me, never below 3%.
You may want to try the 12 hour minimum charge cycles again like when it was new? Also, maybe you could use a better charger/cable? I had a zero lemon that started acting wonky at right about 6 months, and they were good about honoring the warranty. While I was waiting for the replacement, I ordered the Hyperion 7000 mah, and they have a 2 year warranty. I've only had it a couple of months, and so far very much like the zero lemon. It actually seems exactly the same (except for the warranty).
One last thing, and this may not be good advice, but I picked up a rocket fish charger, it charges at 1 mah instead of .5 like the standard charger....Just because it charges twice as fast. No one told me to do that, and I don't know if it's bad or good. I figured they wouldn't sell rapid chargers if they were bad.
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