Which Crimp Connectors For Overkill BMS?

chrisski

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I'm getting two Overkill BMSs, one each for my lithium batteries. These will Attach to Eve 280 ah cells with M6 laser welded studs. I'm having trouble finding parts on line. Sizes I'm looking for are:

M6 Stud to 26 AWG for balance wires
=============
I can't find any of these made, so what have you done for these connections?
In their instructions they list using 16 to 22 AWG ring terminals and a 3/8" ID ring. For ID, I will go with an M6 stud.
1625515585039.png
This will be the first job I will be crimping such small wires, and would like to know if you've used insulated or not.
=======================================================
=======================================================
Two 8 AWG Wires crimped into a 6 AWG Stud
=============================
So this is probably just a misprint and I know I won't be the last attention to detail guy to ever notice that the diagram in the instruction manual erroneously labels the two blue wires as three, but in my case since I'm getting 8 AWG wires, I will use 6 AWG to M6 Studs for crimping.
1625515804574.png
1625516021684.png
 

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Samsonite801

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I just used these ones here and fold the wires either once (to get 2 thick), or twice (to get 4 thick), depending on how small the wires are (to get a tight fit), before crimping them in. You have to twist really tight, crease the wire with your fingernail, pinch very tight, make sure the strands are all good and tight so they all go into the crimp and none are stray. May have to practice a couple times to get it just right.

 

Bubba1

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We could use a sticky thread on different connectors. Going from small wires to large post is not available at the local hardware store.
 

time2roll

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I have the 6mm bolt connections on the OK BMS. I used a lug for the #6 wire with a #10 hole that I drilled to 6mm. I combined the 2 #6 wires into a #4 butt connector to continue with #4 wire. Next build I plan to put a copper bus across the bolt terminals on the BMS and go direct to #4 wire with a single lug.

The balance wires I drilled and tapped a 6-32 hole in the bus bar for a small screw. Then used a solder/seal terminal rated 22/18 wire and #6 hole for the small screw. The solder/seal solders the terminal and heat shrinks in one motion of the heat gun. Solid connection electrically and mechanically.

I have also had better success with a Kline crimp tool 1005 vs the standard wire crimpers. It says for non insulated but I use this on insulated heat-shrink terminal just fine even if it is a bit hard on the insulation. Good crimp without folding the wire.
 

Stepandwolf

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I am in the same predicament. I wanted to avoid soldering as there are lots of comments about not soldering connections as crimping is better. I have the same 26ga wires coming from my Daly. I doubled the wire and it still easily pulled out of the connector. I even crimped so hard when testing that the crimper sliced right through the connector.

I saw someone suggest you first crimp on the white ferrules rated for 22ga, then put the ferrule in the ring connector.

These are the ring terminals I am using that have rings from #10 up to 3/8"

ring terminals

The wire gauge goes down to the typical red 18-22 size, but maybe crimping on a 22 ferrule and then crimping that into the ring terminal will work. Maybe soldering is easier and be done with it.
 

smoothJoey

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I am in the same predicament. I wanted to avoid soldering as there are lots of comments about not soldering connections as crimping is better. I have the same 26ga wires coming from my Daly. I doubled the wire and it still easily pulled out of the connector. I even crimped so hard when testing that the crimper sliced right through the connector.

I saw someone suggest you first crimp on the white ferrules rated for 22ga, then put the ferrule in the ring connector.

These are the ring terminals I am using that have rings from #10 up to 3/8"

ring terminals

The wire gauge goes down to the typical red 18-22 size, but maybe crimping on a 22 ferrule and then crimping that into the ring terminal will work. Maybe soldering is easier and be done with it.
Have you verified that the balance leads are 26 awg.
That is really tiny.
 

time2roll

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I doubled the wire and it still easily pulled out of the connector. I even crimped so hard when testing that the crimper sliced right through the connector.
What crimper? I have good luck with the Klein. Hard on the shrink but holds the wire.

klein-tools-crimpers-1005-e1_100.jpg


https://www.homedepot.com/p/Klein-Tools-Crimping-and-Cutting-Tool-for-Connectors-1005/100630657?
 

Stepandwolf

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Have you verified that the balance leads are 26 awg.
That is really tiny.
Mine are definitely 26ga...I have a wire stripper that goes down to 26ga. It "barely" was able to strip the wire, sometimes requiring several tries to get a bite. It certainly didn't cut any strands as a stripper would that was too small. When I asked Daly before receiving the BMS they too confirmed the leads were 26ga.
 

DerpsyDoodler

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I'm getting two Overkill BMSs, one each for my lithium batteries. These will Attach to Eve 280 ah cells with M6 laser welded studs. I'm having trouble finding parts on line. Sizes I'm looking for are:

M6 Stud to 26 AWG for balance wires
=============
I can't find any of these made, so what have you done for these connections?
In their instructions they list using 16 to 22 AWG ring terminals and a 3/8" ID ring. For ID, I will go with an M6 stud.
View attachment 55153
This will be the first job I will be crimping such small wires, and would like to know if you've used insulated or not.
=======================================================
=======================================================
Two 8 AWG Wires crimped into a 6 AWG Stud
=============================
So this is probably just a misprint and I know I won't be the last attention to detail guy to ever notice that the diagram in the instruction manual erroneously labels the two blue wires as three, but in my case since I'm getting 8 AWG wires, I will use 6 AWG to M6 Studs for crimping.
View attachment 55154
View attachment 55155
3/8" is a bit big for m6. 1/4" is what i used on my m6 terminals.
 

time2roll

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Yes the included crimper looks easy on the shrink but not going deep enough on the metal.

Solder-seal terminals do work well. Heat gun does the whole process.
 

toms

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There are a few threads going on this topic. Look for an open barrel uninsulated terminal, and use the correct crimpers (i use Iwiss)
Automotive wiring (with its associated vibration) is done this way, 26awg is commonly used for signal wires, it is no problem.
 

A.Justice

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I use red Wirefy heat shrink connectors on small stuff like that. 1/4 inch is almost perfect for M6. Fold the bare end of the wire over itself 2 or 3 times, crimp and heat. The adhesive in the sleeve holds the wire in place, and IMHO is less likely to pull out.

Wirefy connectors are the only "small" (10 awg or smaller) crimp connectors that I use anymore, they are thick tinned copper, and the adhesive lined heat-shrink is the bees knees when it comes to clean, professional looking work.

 

DerpsyDoodler

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i bought some e-volt based on Will's recommendation (they were listed on his site).*puke* wont get those again. they were thin and super soft. he had had some others listed that he did a vid about, but i guess they were sold out and he switched to the evolt.
 

A.Justice

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i bought some e-volt based on Will's recommendation (they were listed on his site).*puke* wont get those again. they were thin and super soft. he had had some others listed that he did a vid about, but i guess they were sold out and he switched to the evolt.
Try the Wirefy ones, you won't regret it. They have assorted boxes too, with all kinds of connectors for multiple sizes of wire. They run about $50. Really useful when you are trying to fit something together and don't know exactly what you need.
 

chrisski

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Look for an open barrel uninsulated terminal


This is something you recommend for M6 studs and 26 AWG?


1628202442832.png
And to crimp these:
1628202678048.png1628202699975.png
 

Stepandwolf

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Still just gets you down to 22 AWG. There is a slightly better set of connectors
ring terminals

I already have the crimper for doing the double crimp. At least the crimp around the insulation might hold it from pulling out but solder still might be the best option.
 

toms

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You can get those terminals and crimpers to suit for 26awg wire.

Search Iwiss mini micro open barrel crimper to see what i use.

Solder, especially on very fine wires can cause a stress point that will crack with vibration. The glued heatshrink will look fine, but the wire can still go open circuit. That is why in automotive and aviation etc there are no soldered wires.
 

time2roll

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I believe as long as the heat shrink covers the wire further than the solder wicks up there is minimal to no issue of creating a stress point to break.
 
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