Custom 18650 Battery (Pre-Build)

ESK8 Electronics
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it just so happens that i have a custom build request coming my way and i’m going to need to build a pack.

Depending on the mAh per cell, i may want as many as 60 if enough people get in on it. Otherwise i’ll probably only get 30. plus a couple of extras in case there are duds.

Where do we buy from?

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If my math is right (I’m still learning) your battery would be 180Wh? And weigh approx 840g (1.8lbs) That’s pretty enticing! This just about what I’m looking for thanks for the work and links

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I think so, @Bender Ur welcome! Do you know how to wire the BMS to the battery indicator?? @longhairedboy do u know?? What else do u know about on/off switches for the battery?

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As far as power switches, you can either use the one on the BMS if it has a soft switch (if you’re using a BMS at all) or buy a soft switch similar to what @torqueboards is selling. Or use his, i’ve been pretty happy with the one i got from him a couple years ago. there’s also an open source one somewhere on the web that i can’t find right now that’s basically the same thing, a couple of FETs on a tiny PCB with a low current push button switch attached to it.

The volt meter / fuel gauge can just be wired into the mains after the switch and before the ECSs. On my 6S rat board i have the volt meter soldered into the leads on the switch. ITs as good a place as any. If you put it between the pack and the switch you’re going to end up with a volt meter that’s just always on.

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Thanks for the feedback!

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I just got the Vedder’s SparkSwitch made but made some changes to handle more amperage due to the issues a few people have been having with it.

  • Added wider traces to the PCB.
  • Included 40amp fuse jumpers. Will be XT90 10awg ends (overkill though).
  • It will have the same push button switch as before. Blue LED. I’ve added a 3 pin to make it easier to connect. In the future, I will probably switch this out with a connector which doesn’t come undone.
  • This will replace the switch which I currently have…

4 Likes
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When will it be available… Dumb question… does this mean that you will be able to use any switch with it… just solder to the given ports?

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How are you planning to house this battery? I’m really curious about solutions for that issue. Can’t wait to see your build become a success!!!

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I am going to vacuum form an abs enclosure

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Isn’t your capacity gonna be 5000mah? For the total battery

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How do you calculate it? I was curious becasue they are 2500mAh cells and there is now way its 50,000mAh I am going to plan on making it 10s3p in stead of 2p

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okay so if battery “A” is 3.7 volts @ 2500mah And battery “B” is the same

When you combine them both in parallel meaning + with + and - with - then then the mah jumps to 5000. and voltage stays at 3.7 volts.

SO since this is a 2p pack the mah is 5000.

a 3p pack would be 7500 mah.

If you combine 10 of those 3p packs together in series youll get 3.7volts * 10 packs and you get 37 volts.

Sorry i dont mean to insult you im sure you know most of this stuff already just wanted to walk thru it all in case someone else read this

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Haha not at all! Thanks!

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You only have two batteries in parallel and at 20 amp continuous each that will be 40amp continuous. I would go to 3p so you can have 60amp continuous. Up hills and at high speeds you can easily get past 40 amps.

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Thanks! that’s what i plan on doing!

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mAh are added in parallel, but voltage is added in series.

if you have a 10S3p using 2500mah cells, what you have is a 36V 7500mah pack.

Essentially a space cell.

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http://www.gearbest.com/batteries/pp_254172.html PLUS THE 10% COUPON: 55liuhao (maybe expired, so try FBGBES for 9% off) I just ordered Samsung 25R cells from here, they had the lowest prices I could find, free shipping, and people say their cells are authentic (both on vaping forums and the product’s review page. They also have LG HE4 cells for similarly cheap prices (they’re out of stock for the flash sale, but their normal price is only $1 higher for the 4 pack). I chose the Samsung for their slightly higher continuous discharge rate since I’ll be running a 3p battery.

1 Like
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Haha yes but everything is out of stock! @paragon

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Wow. I was able to order 4 packs of the Samsung 25R’s like 10 minutes ago. I bought 24 cells for an 8s3p pack. It came out to $83 shipped.

Also, the out of stock is just for the flash sale. They’ll be in stock (when it says the flash sale ends) for about a dollar more for each 4 pack. I think it’ll be $15 for the HE4 and $17 for the 25R 4packs, and then you can use the 10% off coupon in my post above.

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You broke it :cry: haha thanks for letting me know/ promo code!