Balance charging and protecting 4s LiPO battery pack
A Protection Circuit Module (PCM) is designed to provide 'last-ditch' protection which (hopefully) prevents damage if other circuitry fails. It is not supposed to be used as a substitute for a proper Lipo charger, or to turn the device off when the battery gets low.

Balancing modules are designed to equalize small capacity differences between cells, to ensure that they all get fully charged without any going over-voltage before the whole battery reaches maximum voltage. Most balancers are not powerful enough to correct large imbalance (which might be caused by mismatched cells or a faulty cell) in high capacity packs. 

After adding a PCM and balancer you may get away with using a basic CVCC (Constant Voltage Constant Current) or current-limited power supply to charge the battery, if it is adjusted to the correct voltage and current and has stable output. However this doesn't protect against severe cell imbalance, low voltage, or other anomalies that the PCM can't detect. 

If you decide to go this way rather than using a proper charger, it is your responsibility to make sure that the battery stays in good health. Measure cell voltages regularly to check that they are well balanced (voltages within +-0.03V). If the battery gets over-discharged then you should charge at a lower rate until the voltage gets to ~3.7V per cell. If any cell shows anomalous behavior (eg. not maintaining the same voltage as others) then it is faulty and the battery should not be used.