Its a used Sunko 709a
my first kweld welds. Nickel to nickel. 0.15x8mm. Do they look ok? Thoughts on which looks better 25j or 30? How does nickel compare to the positive on the battery? Will I need the same power or more (or less)? Feedback appreciated.
Pic of the top
Pic of the underside
Nickel to nickel is weird and different from nickel to steel. Usually need a lot less power to weld to cells.
Nickel to utility knife blades is a decent way to get in the ballpark.
Your photos are a bit blurry, hard to see.
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Ok thanks. I’ve put those strips into salt water so I’ll take new pictures later next week and repost. I’ll also do some nickel to utility knife as well.
How hard should it be to pull apart? Should it rip the strip or break the welds? I’ll need two strips of nickel for my 5p packs so welding nickel to nickel is inevitable.
Thanks!
They need to be strong enough that you’d not question if it’s strong enough, eh?
Personally I’ve not gotten there. Nickel to nickel seems temperamental with lots of variance, and never feels that strong. I usually end up with copper soldered onto the nickel. Others seem happy with it though…
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Some builders who dislike nickel to nickel welding opt for copper bars, like @deucesdown said, while others simply use a 20awg TINNED copper wire like so:
Personally I would ensure the largest amount of contact between the nickel and copper as possible, but this ‘should be more than enough’ for parallel* connections for a 100a battery
(I’ve heard it’s gotta be tinned or it’ll oxidize eventually. I’ve got no clue how that impacts performance, but I don’t want to find out 
)
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If yer soldering, why not put some metal there. 
(IMO the nickel is enough for the parallel current if series wires are placed with consideration)
(hidden because no longer relevant, but the video is awesome!)
Here's Doctorbass again. 100a is a *lot*.
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I saw you typing and double checked my paragraph, I accidentally switched series and parallel in my head. I edited it just before you posted 
This isnt my work, it’s @thisguyhere s and I asked him to beef up the parallel**** bc I was planning on potting it. ‘More ability to carry current = hopefully lower batt temps’ was my rationale behind asking for it.
I do get what you mean about adding more than 20 awg but I was assured many times it wasn’t necessary
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You won’t be pulling 100a continuous. It’ll be 100a bursts of a few seconds at a time. Average amp draw for dual pnumatic is like 15a.
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Jst 2 pin wire thickness test
I decided to check wire thickness between random jst connectors from different ebay/aliexpress sources and one from hobbyking.
Here you can see hobbyking wire on the left and 2 thickest and 1 thinest wires from china on the right:
Conclusion:
Only hobbyking uses real silicone 20awg wire on jst connectors and even best connectors from ebay/aliexpress have less than half strains than hobbyking. Chinese connectors are only good for signal/switch/led display, I would not use them for charging, escpecially not at 5A or more. Some chinese connectors have criminally thin wires and I wouldn’t risk with that. If anyone else has some other source of quality connectors, I would like to know, otherwise get yourself real deal from hobbyking.
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Good study. Thanks for sharing!
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I always makes my own. Due that I can use 18AWG 
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Thats also great idea! So you just plug pins out of plastic, replace wires on pins and return them back in?
You can fit that in JST-XH? You da man.
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Where does everyone buy their silicone wire from?
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In the US acerracing either their website or ebay. Quality is good, prices are okay.
Also scour aliexpress and ebay. Takes so much energy but can be cheaper if buying in bulk. Look for high strand count tinned copper. I’ve not noticed a quality difference.
Sometimes you can find red+black wire fused together, which can be very nice in some applications.
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Am I missing something? I had a spare charge port from meepo, and I added it to my 12s nese pack, but my 12s charger does not fit into the port…
Anyone know where I can get a 12s charge port in the US?
Is that a magnetic charge port?
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