i recently bought an gens ace imars charger 2 from rc mumbai. i used it to charge my 2200mah 3S lipo from rcbazzar and there was no problem. but when i was configuring my charger for 6S 6200 mah tattu lipo i found that the CURRENT value for the charger is going only till  3.96A where as for the 2200 mah 3S lipo CURRENT was showing 2.2A. anyone who has used this charger could tell me is it alright to charge the 6S tattu lipo with 6200 mah at 3.96A?

That charger is only rated for 100W. As power = Volts x Amps, a 6S (22.2V nominal) can only be charged at a maximum current of 100/22.2 = 4.5A which will decrease as the battery voltage increases. The real world figure may be even less depending on your power supply. And yes, charging a 6200 mAh pack at 3.96A should be fine as it is even less than 1C (though it will take a while to charge).

Thanks! Just went ahead with charging but it's not balancing the cells