I'll show you how I make the Li-ion packs that I use for my Long Range FPV flights as well as talk about different cell types, amp handling and more. I would recommend that those new to soldering do not try making their own li-ion packs. The soldering required is more difficult than building a quad. (My middle finger on my dominant hand lost a fight with a skill saw recently so you'll have to excuse me for not being quick enough getting the heat on and off the cells. It should really be done a little faster than in my examples.)

Video chapters:
0:00 - Warning
0:20 - Different cell types I've used
5:12 - What you need to make a li-ion pack
7:16 - Prepping the cells
11:05 - Tinning the ends
19:00 - Cell layout & diagram
24:40 - Making the series connections
28:05 - Adding the XT60
32:48 - Layout & attach the balance wires
39:30 - Foam & electrical tape to protect the ends
43:15 - A final wrap
45:15 - Checking with a multimeter
46:45 - Final thoughts, charging & maintenance
47:40 - Ending / video suggestions

I'm often asked about how I get such good video and transmitter range. The biggest improvement for most will be from upgrading their antennas. I use these ones (Airblade UAV affiliate links):

Goggles TrueRC - X2-AIR: http://bit.ly/3hKcXeS
VTX TrueRC - Singularity: http://bit.ly/2L2YONN
Crossfire Receiver TrueRC - Bardpole: http://bit.ly/38eIhzm

Quad & Gear used (Airblade UAV affiliate links):

Frame - FalconRad 7" V1
Goggles - Orqa FPV.One (Amazing Goggles!)
Goggle antennas -
TrueRC X2-AIR: http://bit.ly/3hKcXeS
DIY 7 turn helical (thingyverse link): https://www.thingiverse.com/thing:367500
HD Camera - GoPro Hero 6 Black
Camera Butter ND filter: http://bit.ly/3rXd0IM
Transmitter - taranis X9D
Tx - TBS crossfire micro Tx at 250mw: http://bit.ly/395NrwR
Rx - TBS crossfire nano diversity: http://bit.ly/3rSWny0
Rx Antennas -
Back/Vertical - True RC Bardpole: http://bit.ly/38eIhzm
Front/ horizontal - TBS extra extended immortal T: http://bit.ly/2MvtyaF
Flight controller - DYS F4 Pro V2
ESC - Diatone 40amp from MK2 stack
Motors - Brother Hobby Avenger 2806.5 1300kv: http://bit.ly/2XaTSZN
Props - Gemfan 7040: http://bit.ly/38YDf9j
Fpv cam - Runcam Phoenix V2: http://bit.ly/2XcHyIs
GPS - BrainFPV GPS: http://bit.ly/38WOiQe
VTX - Tank Ultimate Plus: http://bit.ly/2L33UcT
VTX antenna - True RC singularity: http://bit.ly/2L2YONN

Comments? Questions? Leave them in the comment section below. I'll do my best to answer.

Music all from youtube audio library.