Why do Lipo batteries charge to 8.4 volts instead of 7.4 volts?

[RC_Hobbyist]

I received these Gartpot 7.4 Volt Lipo batteries from amazon.
I put them on the charger today on balance charge & each cell got to 4.2 volts (8.4 volts total) before the charge stopped.

I am wondering why this it charges to 8.4 volts, as the label clearly states voltage is 7.4 volts (3.7 volts per cell).

[bsy2010]

Batteries are always labeled with their nominal voltage, as the actual voltage might vary. In case of a normal Lipo cell, the nominal voltage is 3,7V, a NiMH is 1,2V, but actual values are much higher, like the 4,2V of your Lipo

[Ecky78]

Lipos can be used between 4.2V (which is their maximum voltage where the charging process ends) and then down to about 3V. Voltage drops during usage, as with other batteries.
Actually, NiMHs are also charged to about 1.55V, if I remember correctly.

[RC_Hobbyist]

Thanks for the replies.

As GI Joe said at the end of most episodes "...And knowing is half the battle." 😉

[Wooders28]

The new liHv high voltage lipos are 4.35v per cell. Although racing rules say you can only still charge to 4.2v.

[alvinlwh]

I had seen NiMHs charged to 8.9v before cutting off. 

[Honza]

2 hours ago, alvinlwh said:

I had seen NiMHs charged to 8.9v before cutting off. 

That's a bit different, NiMH charges with constant current, so voltage during charging is higher than voltage of a charged battery. The value depends on charging current and internal resistance.