Have come across the A123 prismatic cells that seem fairly high powered, but would this be a legit listing? https://www.alibaba.com/product-detail/High-Power-A123-LiFePO4-Battery-20AH_62081621477.html?spm=a2700.7735675.normalList.8.1f64446cZ3t9vx&s=p
Seems awfully cheap to me. There are also listings going for around double the above cost. I might order one for science and see what arrives
Shipping batteries is always super expensive, as batteries become more prevalent in literally everything there will need to be changes made to how they are shipped
What price are you selling a battery for? Like a 12s5p or something?
Depends on the battery. 12s5p would cost about 720AUD with a smart BMS.
Dudes.
Can you tell me about the process you use to solder the silicone cable to connect the series?
What soldering iron? How hot?
Do you just do the soldering on top of the p groups as they lay flat? Any concerns with heating the side of the cells?
Any way to protect the sides temporarily?
Do you scratch up the nickel?
Using a 100 watt or better iron solder a pool of solder on the nickel strip b, in between 2 weld points, before you weld the P groups. Use liquid flux to make it stick.
Raf, I use a 3x10mm thick piece of aluminium as a heatsink when soldering on cells, if you need to weld on top of cells, just add tabs and then fold them over on themselves with the heatsink between the tab and the cell.
Be careful not to make shorts tho 
Edit: when soldering to nickel, PLEASE rough up the nickel first
Is the ts100 iron suitable?
I feel like there mayyy be a story in thereā¦
Just a few little sparks here and there
I rarely insulate the terminals that Iām not working on, itās caught me.out a few times.
Good tip for learning battery builders; insulate the terminals that you arenāt working on. Masking tape is a good solution, easy to use and remove and reasonably cheap. Things can go wrong very quickly if you arenāt careful.
Yes, and make yourself foldover tabs so you donāt have to hunt for the end.
Or you could use big masking tape 
i use application tape that signwriters use for transferring lasercut vinyl stickers
I use flux cored solder, scratch the nickel a little (nothing much just a few scratches) and first make a solder pool on the tabs.
Then I pre-tin the cable ends with solder and finally solder the cable to the pool.
I use an ERSA RDS 80 iron
Usually I set it at 400C, sometimes I may increase the temperature to 450C but this burns out the flux very fast so I have to add extra.
Instead of a aluminium bar I usually just put a folded cardboard piece to protect the sides but I all honesty it is more a precaution than need since the sides of the cells are already semi protected from layer of fishpaper under the nickel.
Have you tried splitting the bottom of the 2 p groups apart on a flat surface, then press the center down on the table until it is completely flat on the surface, then while holding both sides flat, push the groups together to compress the center
This is how I do it. As you are pushing the cells down flat towards the table, try to leave a substantial gap between the two packs so that the nickel just ācurvesā and doesnāt actually fold. You want the fold to occur while you have pressure down on them and pushing them together at the same time.
I also like to put something between the two packs. I use salvaged fibreglass strips from other battery packs or strips of those really thin cutting boards.
Edit: also as you are pushing the two packs together, it is also important to add pressure in the direction to make the two packs line up nicely.
Iām not fan of the folding method. Especially if you use multiple layers of nickel and donāt bend them in the right way there will be always stress on the welds which might over time be enough to rip up the nickel connections and in the worst case even cause a short.
Probably not hot enough