What cell voltage should I use to charge a 2S 7.4 V LiPo battery?
It looks like this setting is OK.
One LiPo cell will have a (maximum) voltage of around 4.2 V.
2S means that there are 2 cells in series. In series means that the voltages add up so for a 2S battery you get 4.2 V + 4.2 V = 8.4 V.
Now things get confusing because on your battery is says 7.4 V!
When a LiPo cell is fully charged its voltage is around 4.2 V
When a LiPo cell is almost empty its voltage is around 3.7 V
What they list on batteries is the &quot;almost empty&quot; voltage which is around 3.7 V per cell, of which there are 2 in series so: 3.7 V + 3.7 V = 7.4 V.
Your charger also says &quot;2S (7.4 V)&quot; so that's OK.
The Current setting might be a bit high. I would take that down to 2 or 3 A especially if you can accept the longer charging time.
Charging / discharging cells with high currents decreases their lifetime so if you can, take it slow, use a lower current.
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