Battery building
Here I shall put some step by step pictures to help you put together some packs for the Pic. Note that the battery manufacturers do not approve of soldering direct to cells, it heats up the cell contents and the seals under the +ve terminals. Also I can't guarantee you won't make a mistake with the cells, short them out or otherwise abuse them, so undertake the procedure at your own risk.
Assuming you have a soldering iron, conventional electric iron of 50W or more, or a 100W gun like mine, you will need some flux cored electronics type solder, cables connectors and heatshrink tube. A heat source to shrink the tube, some glue, wire of some kind to connect the cells, insulating tape, and personally I use a flux to help tin the cell ends, I use Fry's Powerflo it doesn't appear to corrode things and I wipe most of it off anyway.
Ok above is what I use to link the cells, it is desolder braid or wick, it is fluxed woven copper and remains flexible. Of course it solders easily, that is what it is designed for!
Tack the cells together (I use superglue though this is brittle and hard to dismantle if you need to separate the cells). Dab a tiny bit of flux on the cells and tin the ends as above. The iron should be hot enough to do the job in about ONE second. If you dont have a flux, it may be necessary to sand a clean spot on the metal.
Solder your link to one cell and trim to length.
Hold down the end with a heatproof tool and solder it to the other cell.
You eventually will have all the links in place. Note the vacant cell end. this would be the -ve lead end for a 7 cell pack, but I needed an 8 cell with one on the end, so it got a bit more complicated next.
I needed two extra "ears" to get the othe cell in place.
Protection required from some heatshrink tube (2.4mm here).
Make up the leads while the cell ends are still accessible! Note block of wood to hold the connectors.
Solder the wire on and..
Shrink some more sleeving in place. Don't leave the ends bare or unsleeved unless you enjoy small fires in the workshop. Then solder the wires to the pack.
Tape over the pack ends. On this pack another cell is to rest here.
Like this.
Cut your large heatshrink about 4mm (3/16) over length and shrink the ends first, then the middle.
Phew finished! Don't worry if your first attempts at heat shrinking are complete disasters, so were mine ;o) And try to get the wires coming out of the correct end of the pack..the above are not - oops. My heli configuration needed the wide cell at the wire end.
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