I really hope that you do not give up, kd. To me, the health benefit/improvement is well worth the effort. Honestly, I don't know what is happening with your attys. Especially since you are having the problem with both 901s and 510s. But...it has been pointed out that your passthrough vapes at 5v, and most batteries, though rated 3.7v actually are only at 3.2. The extra voltage could be the major issue.
Did you try using only batteries on a brand new atty to see if the problem still occurred after a few days? (Not on an atty with which you have ever had this problem - try a NEW one only.)
And do remember that cartomizers can be refilled several times. Perhaps that would be a better alternative for you than atomizer/cartridge combos. They are disposable, and only about $2.00 each, sometimes less. So there is little more cost, if any, to using them. KR808D-1 cartomizers are compatible with the 901 threads, and the newer 510 cartomizers only recently on the market are getting very good reviews. I like them, myself, a lot.
Hang in there!