Would it be possible to make a version without such large gaps between the cells? Quite a shame that this method comes with the size tradeoff.
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You can wire in whatever BMS you want. There’s a 13 pin header that exposes B0- through B12+ and 2x M5 slug terminals for the main battery leads.
Very soon:
No, because the PCB copper isn’t supposed to carry any of the main current; it’s mostly for structural + balance cable organization. Nickel is overlapped so that it carries the current directly between P-groups.
Totally. It becomes a brick pack at a certain point though and you lose any flexibility whatsoever- which might not be a bad thing for most builds. The 12S4P model see here is based on the one I did with @torqueboards for the TB40 deck.
Is there interest in a 10S/12S, more compact version? I can always do a small run of 10 PCBs if there’s some interest.
PS: I am waiting on some more inventory to arrive but I’ll be putting together $5 cable/connector kits to go with these so that people can get 95% of whats needed to build these and just add solder/fishpaper.
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- I’m interested in a more compact 10s version!
- I’m interested in a more compact 12s version!
- These ones work fine for me!
- Not interested at the moment
0 voters
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Okay scratch that- I went and updated the remaining inventory I have of these kits today to expand out what comes with them- I was going to make this a separate add-on kit but I’ve decided to just include it in the base kit to make it a bit more comprehensive. Price remains the same.
Kit Includes:
- 12S4P FlexPCB
- 25x 4p-18650 Pure Nickel p-group tabs.
- 48x Fishpaper Rings
- 2x M5 Bush Terminal (175A rated)
- 13-pin RA JST Header (Balance connector)
- 2x M5 10-12awg Ring Terminals (100A)
- 2x M5 14-18awg Ring Terminals (Balance)
- 2x M5x10mm Socket Head Bolt & Split Washer
- Amass XT-60 Female Connector
- 2x 150mm 12awg Silicone Stranded Cable
- 4x 150mmx10x0.2mm Nickel Strip
- 200x200mm Adhesive Backed Fishpaper Sheet
This should now include everything needed to build out the battery minus cells, silicone, solder, & BMS.
Heads up: After today’s sales I have 4 of these 12S4P kits left, but have a PCB shipment coming due in 7-10 days that will replenish those.
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You sir are a gentleman. I appreciate that
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Possible to use this PCB board work with 26650 cells for a 12s3p pack?
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I don’t have any of those type of cells on hand, but the FlexPCB + the nickel tabs have drawings/dimensions published so you’re welcome to see what could work.
Likewise, the same layout could be used for a 12s7p or even 12s8p double stack with some additional nickel strips and creativity.
I’ll have a 3d model of this battery up by Monday.
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@DerelictRobot, sorry, I should have given you more information for my question.
26650 cells (26mm diameter 65 mm length) are same length as 18650 cells (18mm diameter 65mm length) but have larger diameter.
Based on the dimensions, I think 26650 cells (I’m thinking A123 LiFePo4) should fit, but in a 3p configuration instead of 4p to account for the larger diameter. I’m starting to research battery building and for my first pack I would like to use your PCB kit (convenient, thanks to this how-to) with the A123’s which are dirt cheap compared to Samsung 30t cells.
Sorry for long winded blah blah… to the point, do you see anything wrong (fatal flaw I’m not seeing) with me trying to use A123 26650’s in a 3p with your PCB?
** I purchased, guess I’ll find out
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I’m gonna give that a solid “sure, maybe?” Id have to model it without the cells on hand to know for sure.
these are DIY kits, so you’re encouraged to trim some nickel or even add additional nickel as needed. So long as the cell footprint works you can usually figure out a solution on the nickel connection.
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Does the kit come with the lunch tray? can we request alternate colors; i’m fearful that red may be too fast for a beginner such as myself
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Following this. I recently placed an order for TB40 and I am going to build a 12s4p for it with 21700 cells. This looks promising.
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Worth mentioning that there’s now a more compact version of this with less ‘flex’ is available as a few people requested it:
Compact PCB dimensions:
416mm L x 144mm W x 1.6mm D
FlexPCB dimensions:
439mm L x 150mm W x 1.6mm D
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@DerelictRobot if you need another build guide, just leave your back window unlocked again and turn off that security system you installed after my last “visit.” I’ll come by and “grab” some more supplies. I promise not to steal your dog this time. 
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Just wanted express my appreciation for this battery kit. waiting on a BMS, but so far it’s gone together really well.
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Super clean assembly dude!
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Looks like I’ll need the female 13 pin JST Connector to connect the balance wires to BMS (unless I’m missing something). What size JST pin came with this set? I’d measure, but I’m not crazy about sticking my calipers between the battery terminals.
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I believe it’s JST PH, but dont take my word for it. @DerelictRobot care to clarify? Maybe good info to include on the product page as well.
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13 pin JST PH 2.0
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Good call, going to have actual 13p harness cables soon too.
Champ!
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