I have a powerflite charger that ive been using for years on my old powerflite li-ions , but with in the past year i "upgraded" to fromeco relion 5200 mah li-ions

i'd like to know if my old powerflite charger with an output of 8.4 volts and 1200mah is sufficient enough to maximize the capacity of my fromeco relion 5200 mah 7.2 volt battieries