I am updating my NIB pack build for the sakes of anyone that might be secretly interested... Everyone has different needs, I need a pack that doesn't need frequent charging, I aim for once a week, I don't have access wall power socket where I keep my bike..
My pack is now a 12S7P of 18650s Samsung 29Es. In case some don't know 29Es can discharge down to 2.5v..
http://lygte-info.dk/review/batteries20 ... %20UK.html
I am using 60mm wide copper foil to connect the cells, one strip of copper foil connects the positive and negative sides of each cells.. This was the copper foil I used, one side is adhesive.. http://www.ebay.com/itm/60mm-10m-Pickgu ... 53e150f8d8
Doubling or tripling thin metal thin foil metal gives better cell terminal contour than a single thick ply of metal..
*Edit/Add* I have realized some folks aren't going to read this entire thread but I recommend you try.. So I have to point out one of the most important things you should do when trying to make these packs is use "Paper Insulation Gaskets" lots of different sizes on Fasttech.com
If you don't you might create a situation like this https://youtu.be/ZTzEHsJVZhA
..lots of lithium cell fires out there but how about a wound video? https://youtu.be/tnuKR0i4b-s
I also replaced my EM3EV bag with a Lunacycle bag, and also not using the Dolphine battery case at all atm.
The Trek logo is now easily visible and everything else looks a lot better on my bike now, the EM3EV bag overly covered the bike/frame.
On my last major full use of the battery pack I connected a power meter onto it, the pack cells were charged up to 4.16v each.
I rode around at an average of 350watts I would say and traveled 81 kilometers.
I weighed the pack and putting the cells aside the rest of the pack being wires, tape, and nibs added about an extra 550grams of weight I estimate from the weight of cells are 48g each.
The pack doesn't have a BMS and I charge it with a pure parallel balance battery charger, the pack is easily split-able in half with a simple removable link in the middle so I can charge at 6S on a BC168 or similar charger. With the middle link removed the charger sees the pack as 6S14P. It's very important to unplug the charger before reconnecting the middle link.
http://www.radiolink.com.cn/doce/produc ... l-102.html
I did away with crappy unreliable JST connectors and instead used trailer connectors which are quite similar to bullet HXT lipo connectors but in a convenient 7 pin one way only style plug. All with thicker wiring gauge wiring then JST...
http://www.banggood.com/7-Pins-12n-Trai ... 55839.html
I soldered the connector/male plug directly onto the BC168 type charger.
http://www.banggood.com/Tirol-Wire-Conn ... 57602.html
I think the construction is self explanatory but I will try and fill in some bits.. it uses standard 18650 cell separators..
I wrapped the whole thing in kapton tape..
When using the 60mm copper foil I placed the foil directly over the bare cell terminals.. and then the nibs on top and there is enough copper foil on the sides to wrap over the top of the nib magnets so they can never jump.. It effectively becomes a whole 7P 2S copper tab strip with magnets on the inside..
The magnets are placed all with the same uniform polarity, this way they all tend to oppose each other from jumping naturally.
Every time I have looked at it over the last few months of using it I ask my self "is this safer then my lipo packs?" and the answer for me is yes. If you had to ask me the question whether it would be safer for you, then I would probably be forced to say no because you shouldn't be asking me that question, you should have confidence in your own builds..
As you can see its no pack of beauty, I have always approached it with zero aim of impressing anyone.
I will probably edit this specific post and answer any questions to help make it a single informative post..