I was gonna say… I don’t think I ordered that many 
That Kweld Holder is dope!
2 Likes
After lots of reading, I was wondering if this battery construction method will work. This is taking part of the PCB’s construction method and part of the nickel belts construction method.
The cells shown are large QB 26800 cells: https://www.aliexpress.com/item/32955965193.html?spm=a2g0o.detail.1000060.2.52334aeaJyyvj8&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.128609.0&scm_id=1007.13339.128609.0&scm-url=1007.13339.128609.0&pvid=7874d22d-9aab-4d05-ac55-639b4429b5e1
And the nickel belt is .15mm x 100mm from here: https://www.aliexpress.com/item/32849118805.html?spm=a2g0o.detail.0.0.2b937f36DMhtI3&gps-id=pcDetailCartBuyAlsoBuy&scm=1007.12908.131037.0&scm_id=1007.12908.131037.0&scm-url=1007.12908.131037.0&pvid=4fa16210-ca9e-465e-9b8b-deb5c0d0d6aa&_t=gps-id:pcDetailCartBuyAlsoBuy,scm-url:1007.12908.131037.0,pvid:4fa16210-ca9e-465e-9b8b-deb5c0d0d6aa,tpp_buckets:668%230%23165967%231_668%23808%234093%23886_668%23888%233325%2311
I am planning to build a massive dual stack12s6p or 12s7p pack. (12s7p in images below)
- The cells will be hot glued together.
- 26xxx fishpaper o-rings on the positive side.
- A fish paper that wraps around the entire P group. (Or perhaps 3D printed shell)
- .15mm x 100mm nickel belt that is spot welded on all the cells
- the top part of the nickel belt bent over the top
- 10awg silicon wires soldered to the top tab that will connect the P groups.
- the balance wires will attach to the top tabs as well of each group
- The entire completed pack wrapped in kapton tape and heat shrink
Let me know what you think
And depending on how nice I can cut, maybe make the nickel into this shape:
3 Likes
would you not put any cuts to bridge the welds over?
what do you mean?
Like the slits here?
https://images-na.ssl-images-amazon.com/images/I/81XFwzRYs1L.AC_SL1500.jpg
I was thinking it would help the nickel bend to touch only on the center of the cell as well as make better welds.
1 Like
What do you guys think is the most efficient and cheap way of testing the capacity of multiple cells? Would like some sort of rig that can do at least 8 cells at once.
1 Like
Buy 2 if those cheap 4 cell charger/tester units.
Cheap and easy.
4 Likes
Or order a handful of these or similar. https://www.aliexpress.com/item/32960593121.html Just make sure to check them for reasonable accuracy first: test the same cell on each one to see how close the readings are between them. @whaddys
2 Likes
Dude. We need print files if you’re just gonna come in here and drop porn
3 Likes
Is there a video of how to use one of these? I think i actually have one, plugs into my USB but I never knew how to wire one properly to battery. Do I need an arduino to make these work?
It’s pretty simple - Four connections, two for battery input, two for a load resistor. They’re labeled on the underside of mine.
Hook up the cell under test and a suitable resistor as a load, apply USB power, and hit the “OK” button. The module will begin discharging the cell through the resistor, while monitoring the current. Once the cell reaches the cutoff voltage (set by pressing the + and - buttons, default 3v), the module stops discharging the cell and displays the discharged capacity.
1 Like
kweldbattholder.STL (346.6 KB)
Print it vertically with the compression prongs facing up and it needs no support. All overhanging arches are rounded. Fits both the Turnigy nanotech and graphene 3s lipos. I stuck a piece of rubber to the prong for to keep the batteries in place better. Strip of VHB tape is holding the weld print solid to the tray atm
1 Like
All good, my printer is broken anyway. But this one is going into the print bank for sure 
cheers brother
2 Likes
https://lygte-info.dk/review/Review%20Charger%20LiitoKala%20Lii-500%20UK.html
You can find these for $20-30. Banggood coupon codes, etc.
Somewhat inconsistent. Read the review.
1 Like
Folks who use that Chinese Bluetooth bms, shouldn’t the app show individual cell voltages?
I only get the front page with no options.
Click the menu button in the top left and go to “battery state” then swipe over to the right one screen to “battery voltage”
Edit: actually looks like you figured it out, from your post in the pictures thread
Figured it out, had to downgrade the app
Wondering what the difference is D595 has 12 pins for balance connector and D140 has 13 pins?
From the looks of it b- is missing from the D596
Wondering if I can simply solder the b- to that pin on the D140. I am switching from the huge D596 to the small D140. Also wondering if I left b- with nothing in it, would it even matter?
Run continuity test from B- to that pin. I’m pretty sure it’s connected together and redundant but not 100%
2 Likes