I have doubled up the wire, tripled the wire, quadrupled the wire, different connectors, different crimpers, and when I am done, I either crimped so hard to smash things into oblivion or the wire pulls right out. Must be me as so many of you succeed without failure, but then even Andy screwed up one of them
I have took one of my spare busbars and drilled a hole in it, and used a tap and die set to make a hole for a screw. This method could be used to get an open end connector or other type of connector sized for a 26 AWG wire. I think most of us are having trouble because there is not a 1/4" to 26 AWG open end crimp available, so we take the M6 which is made for a much thicker wire and make do. I have a 26 AWG open end crimper, but when I use it on the M6 crimp, it bends it:
That orange tool could crimp a 26 AWG (.14 mm2) crimper, but with the M6 stud, its just to big. A smaller stud or screw would work, it would just have to be screwed into the busbar since it won't fit on the battery stud.
This is how I have decided do 26 AWG to M6 stud on an open end crimper. I don't double and triple bend the wire. I put heat shrink on first because it won't fit over the M6 connector and then using my MC4 crimper with a 2.5 mm2, 4 and 4 mm2 crimper. I crimp the insulation on first, then crimp the wire on. For the insulation, I use the 4 mm crimp, and for the wire I use the 2.5 mm crimp. On the orange tool pictured above anything smaller than the 2.5 mm crimp bends the conector so I use this tool which the second photo shows the crimp size:
This is still too loose and will pull out. so I take a pair of needle nose pliers and crimp the 26 AWG end so it ends up looking like this:
I then take the heat shrink put it over the wire and heat into place:
I've done this on the two 25 ah battery packs I am using and have put this on my 280 ah eve cells.
For those Eve's using a BMS, I have pre-charged to less than 3.45 volts per cell, 27.5 volts Absorption Charge, and now that they are at 95% capacity, I will put them in parallel to finish off the top balance at 3.65. This pic is the BMS app from just before taking the 8S 24 volt battery off the pre-charge, disassembling, reassembling in 8P, and starting the top balance at 10 amps and 3.65 volts.
I pre-charged these cells to avoid being on the 10 amp power supply at 3.65 volts per week.