I mean the D140 is $30…isn’t that reputable?
Also not a clue, all I know about them is they are no longer around
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My bad I meant the ‘no name’ chinese ones 
Cory told me my 10s2p had a d140 on it, and it served me well
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Been using 3 of the red water proof guys wired charge only for the past 6 months with no issue yet. I like the size and they dont get to hot when charging 4a. 10S only so far, I’ll give a 12S one a try a try soon too.
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Thanks for the info! I’ll be charging my pack at 3a for now, so hopefully my thermals will be as good as yours 
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Is it safe to run 30A through 40mm of 0.15x10 nickel?
You should use multiple strips, I’ve heard people are getting super wide nickel for carrying more amps as well as being easier to use.
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Ahh this is perfect
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I think these ratings are pretty conservative, but they provide a great point of reference.
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Anyone has tried out these battery packs from Metroboard?
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Hi Guys, I am partly rebuilding/revising a 10S4P 30Q pack. In this pack the poles of different P-groups are opposite to each other.
How do I make sure the poles in the middle won’t short out? What’s safe enough for this? I thought about fishpaper + shrink wrap on each side but I’m not totally sure.
Here’s the pack, that’s how it will go together too:
Note: I know some places don’t have fishpaper where needed. Still need to do this as I removed it because it wasn’t looking amazing anymore.
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i did…and it stopped charging less than a week. I sent it back to them… December 11, it was delivered December 17. I have not heard anything yet…i think things are slow because of the holidays. waiting to see what is up with it. I got the 10s5p one.
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Still trying to think through the details, but it seems like this should work, yes? I’ve got two layers of fish paper under the bar and I’ll put a layer of k tape under there also before I’m finished. Seems like this will carry the current better than the nickel that I have on hand.
Thoughts or suggestions?
Thanks!
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Has anyone built with Efest or Hohm Tech cells? Did they live up to there specifications?
I think the solder joints are a bit cold, they should flow out more. And I hope you trimmed the corners of the nickel on the positive terminals
But yeah that’s should work, someone recently advised that layout to me
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Thanks! I have not yet done anything regarding the positives other than trimming the corners 
I’ll be more careful with the solder moving forward. I don’t think I’m going to use this one for anything more than a template. If I reheat it can I make it better or does it not work like that?
If you use a really hot solder iron and flux it works well, I run mine at like 800C with 63/27 flux solder, it makes massive joints super clean
You should be able to reflow a joint if you add a little more solder so it conducts the heat
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Seems like the same copper I am using.
From what I can gather it is only rated for 20a. How are you planning to do your series connections from there?
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I would switch to braided copper. The bar should work fine but just looks like there is potential to be a lot of bumps and sharp edges. Less of that the better.
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Yeah its not fun to work with, but soldering through the middle of braided wire isn’t a bunch of fun either.
A dremel makes short work of the sharp edges
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