Need help with LiPO batteries
We have used LiPo in parallel successfully. Parallel cells must have the same batch #.

When charging, use a voltage regulated source set to (slightly less than) the 4.2 volt cell charging voltage. 

Look at a DC-DC converter with a current limit at 1C (240mA)

So you need a modular DC-DC converter for rated at 400mA, at 4.2V.
The upright-PCB ones are available from RS etc...