14S6P Triangle Pack build using Samsung INR18650-20R cells

[migueralliart]

Just wanted to make a thread showing the steps I took in my triangle pack build so that others going that route at least have some guidance.

Last night I was thinking about my next build which is going to be a hardtail + MAC and it occurred to me to make a triangle carton cutout of the frame so that I can make an ABS enclosure.

I already know what the configuration is going to be;
9 fet controller from cell man with upgraded MAC and then the battery which will be explained throughout this thread.

The first thing I did after I got my frame was to make a crude carton cutout of the frame.



From there I took the approximated lengths of the 3 sides with a good measuring tool and proceeded to find out the three interior angles (always remember your trigonometry).

Then on to google sketchup to see how much pack I can put in there. I opted for 6P bricks in 2x3 configuration using the spacers that the seller provided. The spacers are 20mm squared for a single cell so when changed to inches it is about 2.36" rounded it to 2.4". I did the same with the width which is 40mm = 1.57" rounded to 1.6"

So you draw the sides of the triangle with the angles then go 3/16"(ABS THICKNESS I TYPICALLY USE) to the inside and then start laying 2.4" x 1.6" rectangles in there. Please make sure you do so conservatively. Don't stretch your space or go over the interior lines. Keep in mind you will need two or three bolts so leave room for that too. ALso take into account the discharge leads and interconnection leads. I'll take more pics of this later when my packs arrive.





After that I then made a layout ppt so that the battery supplier knows what I exactly want in terms of interconnections. See below;



Within 30 minutes I got a quote and paid via paypal.

I went to bed around 11:10pm last night. This morning I checked my inbox and there I had all the pictures of the packs built before being shipped so that I could verify all looks good.

3S6P TOP







5S6P MIDDLE



6S6P BOTTOM PACK





And then all packs done





Total capacity is 12AH. The pack is 14S6P ~600Whr 120amps discharge capable (tabs will melt or get hot) we'll see about that.

Stay tuned for more. The pack was shipped today in 3 split packages. I hope I can get the ABS enclosure here in time for that.

 

[bonald]

that's nice.
i am curious what price you paid.

 

[migueralliart]

Paid 560$ TOTAL with expedited shipping because

AIN't NOBODY GOT TIME FO THAT

 

[migueralliart]

Got everything delivered today... except the ABS enclosure which will be shipped sometime next week

Here is the package as FEDEX dropped it.



One of the packages was inspected by FEDEX and passed (luckily). But they did a really BAD JOB at closing the package.



Inside the package




Three packs inside the bubblewrap





The sides of the pack is not exposed. It is covered with a temporary adhesive cardboard.



And then all the packs overlaid inside the triangle for measuring.




Waiting impatiently for the ABS enclosure.

 

[spinningmagnets]

I have been studying these cells on and off for the past two months. The more I look at them, the more I like them. The NCM and NCA cells are more expensive for only a small improvement in capacity (if all packs have the same size). NMC and NCA C-rate is better, but for a significant price benefit, the excellent C-rate of these cells may be "good enough".

I'm still searching as to how they improved the C-rate, and I think it has to do with the internal construction rather than the chemistry. The chemistry is the same safe and long-life LiMnO2 that Justin at ebikes.ca has had very good luck with for years.

 

[sabongi]

Where did you order the ABS enclosure?

 

[migueralliart]

I have been studying these cells on and off for the past two months. The more I look at them, the more I like them. The NCM and NCA cells are more expensive for only a small improvement in capacity (if all packs have the same size). NMC and NCA C-rate is better, but for a significant price benefit, the excellent C-rate of these cells may be "good enough".

I'm still searching as to how they improved the C-rate, and I think it has to do with the internal construction rather than the chemistry. The chemistry is the same safe and long-life LiMnO2 that Justin at ebikes.ca has had very good luck with for years.

I've been studying the discharge graphs a bit and I noticed there is a slight "increase" in capacity when discharging each cell past 10A. This could be due to the cell warming up? Maybe Luke can comment on that as I'm no chemistry expert, I just buy and test the $hit out of it.

So far I managed to burn my 40amp fuse in my small pack (12S4P) 2 times. This is due to the controller not being programmed correctly. I have to go back and put it at 32-35 battery current. Blowing that fuse does tell me these cells can do some serious discharge. I just got a 18fet setup to 60 amps and I have a modified yescom 1000 watt hub sitting there that I might test out with it. We'll see.

 

[migueralliart]

Where did you order the ABS enclosure?

The ABS enclosure was ordered from pololu.com

You need to provide them a 2D drawing of it in the dxf format and they can give you a quote.

 

[migueralliart]

Weight of the batteries without cables or balance plugs = 8lbs 10oz

WHERE IS MY ABS ENCLOSURE!!! I can't wait for it to get here.

 

[agniusm]

This is a beautiful battery pack. Well done

 

[ken1645]

I'm looking forward to seeing you fit all those in that frame. Best of luck once your ABS pack arrives.

 

[pwbset]

WHERE IS MY ABS ENCLOSURE!!! I can't wait for it to get here.

Dude duct tape that bling and get riding already! :wink: 8)

 

[richmpdx]

Really interesting triangle pack. Any updates?
Rich

 

[migueralliart]

So far I have not received the ABS enclosure. I was away for a couple of days and all the orders from the website were just sitting there. All is shipped now so I might get some time now to track the package and start taking pictures

 

[migueralliart]

Well I received the motor and enclosure. Here are the pics.

After a long weekend of vacation this build is back on track.


Anybody know what the bottom bracket width should be for a rear 7 speed freewheel and MAC?

Is it 122mm?

 

[cal3thousand]

Orlando:

Where did you order the battery pack from? Link please?

 

[migueralliart]

Orlando:

Where did you order the battery pack from? Link please?

This is her contact info;
supowerbattery@gmail.com

You can add her to google talk and she connects every evening after 9pm until 9am.
Tell her you are from ES and your config. If you need any help let me know.

 

[cal3thousand]

Thanks!!