Thank you for your suggestion lemming.
I'm sorry to bother so much but I just realized that these phone batteries have 3 (-) contacts and that they are isolated (no continuity). I always thought they were connected. Could I use one (-) contact for charging from one solar panel and one of the others to put the batteries in series, or is it to perfect to be true?
Edit: Never mind...the other contacts aren't Ground but temperature and something else 