I'm starting to have second thoughts about the aftermarket chargers, I've been using one, not the same one posted here but I also got it from Amazon, I figured it's be safe as the balancing circuit is in the smart battery brain, however I just started having very bad power problems and after taking my I1 to the DJI Store by DroneNerds I found that ALL 4 of my batteries are shot, bad cells on all of them, well I have one left (TB47)to check but all my TB48s are done, now I need someone that knows how tho get them balanced again, trying the discharge recharge trick now to see if I can salvage something. Only common denominator that could be at issue is the aftermarket multi charger.