The Flight Pack Battery Config is how you have your batteries configured for a single flight.
The battery config is written as the total number of cells in series (S), followed by the total
number of cells in parallel (P) and finally, the total capacity of your battery config (mAh).

If you fly off a single battery, then the configuration is simply that battery. For example, a
single 3cell 2200mah pack is three cells in series and would be displayed as '3S 1P 2200mAh'

If you fly off two 3cell 2200mah packs in parallel to get extra capacity, then the battery config
would be '3S 2P 4400mah'

If you fly off two 3cell 2200mah packs in series to get higher voltage and make a 6cell pack, then
the battery config would be '6S 1P 2200mah'

If you fly off four 3cell 2200mah packs in parallel and in series to get higher voltage and extra
capacity, then the battery config would be '6S 2P 4400mAh'

And finally, you may mix different batteries to acheive different cell counts. For example if you
have a 3cell 2200mAh pack and a 5cell 2200mAh packs, you could mix them to get an 8cell
setup. This battery config would be '8S 1P 2200mAh'

Likewise, you could mix two 3cell 2200mah packs with two 5cell 2200mah packs to get an 8cell
setup with twice as much capacity. This battery config would be '8S 2P 4400mAh'