Battery help

[ModBod]

Doing some reading on batteries and dont understand why specs on battery say 3.6 volts when a full charge is 4.2 and which i would use for ohms law

 

[The Cromwell]

Depends. The output voltage will drop under load. For example a GOOD fully charged 10 amp rated 18650 will likely put out no more than 3.7 volts under a 20 amp load.
But under a 10 amp load it may put out 3.9 volts.
And under a 5 amp load it may put out 4 volts or more.

If you are talking mechs and doing cloud builds figure on ~3.7 volts if a fully charged GOOD battery.

 

[Carambrda]

http://batteryuniversity.com/learn/article/confusion_with_voltages