LiPo Charging Voltage and Operating Voltage problem
I would not recommend charging a LiPo battery with a simple voltage charge. The normal charging regime is:


Constant current, then
Balance, then
Constant voltage until terminal charge state is reached, then
Disconnect charging voltage


LiPo batteries do not like float charges. Taking shortcuts can result in damage to the battery or a catastrophic failure resulting in an explosion or fire. I recommend that you acquire a properly constructed charger for your LiPo battery. A LiPo charging/storage bag is a good accessory to avoid spreading damage should a catastrophic failure of the battery occur.