Most chargers has Balancing Charge. Chargers peak out at 8.4v. I think all lipo's are not equal. It charges to the average of the 2cells. 8.69v for both cells, if you check out the voltage in Balancing mode, 1 cell could read 4.34v the other cell could read 4.05. It'll be the average of to cells total.

If you cycle the pack, it'll even itself out. Most chargers cycle 3 to 5 times charging and discharging, function cam take up to 10hrs or more. I do it 3x every 6- 8 week depending on usage.

Chargers are the same, difference is cosmetically. Function are the same. They came a long way, to keep it safe in the hobby. Good question to ask. Storage of lipo, I think should be taken, store the @ 1/3 the capacity, fully charged and stored could be the problem of puffing up or ballooning.

Be safe!! have fun!!