You can charge lipoly batts safely in parallel as long as you dont go over 4.2 volts max , dont go over 1C charging current and the voltage of each cell should be resonably close( dont charge a half full cell with a very low one).
You need a CC/CV ( constant current / constant voltage) charger or a lab power supply where you can set the voltage and current limit.
They can be charged in series 4.2, 8.4, 12.6 volts but you should use a ballancer. Without it, sooner or later the cells in series will charge to different voltages some higher than 4.2, and lipoly's have a bad habit of igniting if over charged( or over discharged, below 3 volts ruins lipolys , or discharged at to high a rate), and they burn very violently.
This isnt a maybe. If you abuse these you will have a fire!
sam
P.S. If the batteries puff up at all while you using them( they are junk) discharge them with a resistor and them drop them in salt water for a couple of days. Always charge them in a flame proof container and never unattended.( no joke)