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Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 13 2019 1:28pm
by Offroader
hgclobo wrote:
Dec 30 2018 1:11pm
Thanks for showing the frame clearance, it does look very close, I’ll keep an eye for that, still, I’m worried about the max space between crowns, its too short for the bomber 380 at only 148mm, damn, I’m gonna pass on this offer I found and look for other forks.
Frame clearance will be close if the top crown slopes down, I believe most don't. Depending on the fork you will have to see how much room you have to raise this.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 13 2019 1:39pm
by Offroader
Decided to pull my 280 cell pack after a couple of years to finally add my Adaptto max-e BMS. Without the BMS, all cells were still balanced so the BMS was not needed.

I used 28 gauge silicone wire for the BMS.

The battery was still fairly tight in the frame but not as tight as it used to be, the foam did loosen a bit so I will be adding some foam to make the battery more secure when putting it back into the frame.

Image

My spot welder I used to place the cells in parallel to add the BMS. Those probes are attached to super flexible silicone 4awg wire, the long flexible wire makes working on the battery easy.

Image

I added small nickel strips to put the cells in parallel

Image

I then soldered my BMS 28 guage wire to very small nickel strips and then welded them to the battery, this way I did not have to solder anything on the battery. Not soldering anything to the cells may have been the reason why my pack stayed in perfect balance.

Image

I plan on putting the BMS in this location at the top of the bike. It will be encased in the foam. The Max-E BMS is very small.

Image

What my battery looks like with the BMS finally wired in. The pack has been wrapped with first Kapton tape to avoid residue on the nickel, then with clear packaging tape to hold everything tight including the wires I used to build the pack. I put some electrical tape over the wires because some wires looked to have been rubbing on the sides of the frame.

Image

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 13 2019 7:39pm
by Merlin
what the heck is this :shock:

i thought (all the years) your copper wires were soldered to ALL CELLS.
did i miss something on that pics?

are your series connection this tiny 0.15 strip of nickel?!

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 13 2019 9:50pm
by Offroader
Every 2 cells has a 16 gauge wire that puts the cells in series.

I soldered the wire to the .2 nickel. Then I spot welded the nickel with the wire on it to the cells. This way I never had to heat any cells up.

You can see in this picture the 16 gauge wire connecting the cells, the cells are not in parallel here and I ran the bike like this for 3 riding seasons. There are 14 cells in each series group.

Image

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 14 2019 4:22am
by madin88
Offroader wrote:
Jan 13 2019 1:39pm
I added small nickel strips to put the cells in series
typo? because the small nickel strips put the cells in PRALLEL (on one side only), and the wires make the series connection.
When you built this battery, safety wasn't first priority, right? but it's good to see that it stays balanced so well :)

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 14 2019 10:19am
by L3chef
Just a noob walking around trying to learn.. So..
Why would it be safer to have 14cells in parallel wired to next series connection, than 7*2 parallel groups --> Serie..?

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 14 2019 12:17pm
by Offroader
Opps, yes I made a typo.

The little nickel strips were to put the cells in parallel.

The cells stayed surprisigly perfectly balanced in almost 3 years.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 14 2019 12:23pm
by Offroader
L3chef wrote:
Jan 14 2019 10:19am
Just a noob walking around trying to learn.. So..
Why would it be safer to have 14cells in parallel wired to next series connection, than 7*2 parallel groups --> Serie..?
I do not understand what you mean by 7*2.

There really is no other way to do this for 20s, 280 cells and keeping each group at 14 cells.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 20 2019 7:23am
by L3chef
Offroader wrote:
Jan 14 2019 12:23pm
L3chef wrote:
Jan 14 2019 10:19am
Just a noob walking around trying to learn.. So..
Why would it be safer to have 14cells in parallel wired to next series connection, than 7*2 parallel groups --> Serie..?
I do not understand what you mean by 7*2.

There really is no other way to do this for 20s, 280 cells and keeping each group at 14 cells.
I understand your battery pack as 20s2p and you have 7 of those wired in parallel to make 20s14p.. Well at least before you added the smaller nickel strips..
I wanted to know why this method would be less safer then do it as you see most packs built.. First all cells in parallel and then to series and so on..

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 20 2019 10:08am
by Offroader
L3chef wrote:
Jan 20 2019 7:23am
Offroader wrote:
Jan 14 2019 12:23pm
L3chef wrote:
Jan 14 2019 10:19am
Just a noob walking around trying to learn.. So..
Why would it be safer to have 14cells in parallel wired to next series connection, than 7*2 parallel groups --> Serie..?
I do not understand what you mean by 7*2.

There really is no other way to do this for 20s, 280 cells and keeping each group at 14 cells.
I understand your battery pack as 20s2p and you have 7 of those wired in parallel to make 20s14p.. Well at least before you added the smaller nickel strips..
I wanted to know why this method would be less safer then do it as you see most packs built.. First all cells in parallel and then to series and so on..
Since I wanted to build the largest battery possible to fit inside the Q76R frame, the battery had to be rounded. Most ebike batteries are square and makes it easy to build.

This is debatable, but at the time I built the battery, there was talk about how the series connections current path needed to be equal between all cells or some cells would have different resistances and would cause some cells to have more or less current draw. Or certain cells would have more load on them then others and this would cause issues.

Think of it like this, if you had a 2s2p pack, one cell had a 30 gauge wire connected in series and one cell had a 4 gauge wire, it is possible the cell with the 4 gauge wire would take much more of the load.

In order to get equal current path or equal resistances for all cells in my round pack I had no choice but to use wires. There is no way you could build that with nickel strip. Every two cells share the same length 16 awg wire.

Another advantage is that 16 awg copper wire has also much less resistance than 100% nickel strip, so battery power losses should be lower.

Since I built my pack I never bothered to put the cells in parallel. Some cells have 2 cells in parallel, many have only 1 cell in parallel because the other side of the pack may not have the same two cells connected with nickel strip.

Was it worth building the pack like this? I do not know and it is debatable if it really made any difference. I do know that in almost 3 years of use this pack was never balanced and still holds perfect balance. And this is across individual cells as the pack was never put in parallel.

The problem with building a rounded pack is that the cells on the outside of the pack could have higher resistances and it is possible those cells would not be used as much, causing the cells with the lower resistances to be used more. I don't know if this really matters because electricity flows at the speed of light and while there would be some current differences between cells it would be so small as to not matter.

Like one cell may draw 8.92 amps, and another cell on the corner of the pack may draw 8.86 amps. Totally negligible.

However when I built the pack I was under the impression that some cells may draw maybe 6 amps and others 8 amps in the same parallel group, now that would cause issues.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 20 2019 10:21am
by Offroader
Here is the post that I mostly followed when designing my pack. You can see I followed the design in the bottom right of the picture and using wires allowed me to do this very easily.


https://endless-sphere.com/forums/viewt ... 96#p920396


To improve your battery life and cell overheat I would suggest to improve the current share between the cells. The actual connections you make on each 1s group make the cell closer to the center to suffer more than the cell around the group.

Image


The nickel have high resistance and the cell closer to the main serie connection will suffer and be drained at higher rate than the rest.



here is a representation to explain and also some ex of solution I suggest to resolve that:

Image

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 25 2019 1:13pm
by TheBMallory
The last few posts convinced me to build a custom battery pack for my q76r and I'm currently ordering some sanyo cells from @tumich,

i do not have them yet so I can't test fit them. I'm planning to build a 20s12p pack and here's what I came up with :
Image

@Offroader: I don't understand how you can have a 20S14P pack. I suppose you gain some vertical space by stacking the cell in a zigzag fashion instead of the rectilinear way shown in the pic ?

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 25 2019 6:03pm
by Offroader
The max I could fit was a 20s14p or 280 cells. This was such a tight fit the pack had to be glued together compressed inside the case to make sure it fit.

My Qulbix frame is the original or old version. If you bought your frame in the last couple of years the frame opening is actually larger. It would have been so much easier to build my 20s14p pack in the newer q76r frame.

Here is my frame with 280 cells compressed together for gluing. It was a pain to do it like this. It is much easier to just glue the cells and place them next to each other but the issue with that is you increase the pack size as it isn't compressed and the glue adds space.

Do you really need a 280 cell or 20s14p pack? Probably not, This is way more capacity than I ever need. However, it will be easier on the cells and allow more peak power by building a pack with more cells, especially if you are using 3500 MAH cells.


Here is my 280 cell pack. The paper around the pack is to compress it together as there were about 8 cells that were almost touching the frame opening. Your frame opening is larger so you will have much less issue with a 280 cell pack.
Image

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 26 2019 7:00am
by TheBMallory
actually I got one of the first frame also. I've been using it with a 48v 20inch magic pie :
Image

and after having almost bought a sur-ron, I figured it would be cheaper to at least first put a proper motor in the qulbix. I'm going to buy the moto seat an foot pegs too.

did you ever drain your battery entirly ? how much time of off-road use do you get ?

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 26 2019 3:10pm
by Offroader
What do you mean drain the battery entirely? If you mean like drain it until its close to 0 volts, never did that. I go as low as 3.3 volts per cell.

My Q76 saw lots of hard off-roading, at least half of my riding.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 27 2019 9:06am
by TheBMallory
I was going to rephrase to "did you ever drain your pack to the point of having the low voltage cut off kicking in" but then I realized you didn't have a bms until now...

Basically I'm trying to guess how much of a difference there will be changing from my current 960wh battery to a 3kwh one in terms of riding time

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Jan 27 2019 11:24am
by Rix
TheBMallory wrote:
Jan 27 2019 9:06am
I was going to rephrase to "did you ever drain your pack to the point of having the low voltage cut off kicking in" but then I realized you didn't have a bms until now...

Basically I'm trying to guess how much of a difference there will be changing from my current 960wh battery to a 3kwh one in terms of riding time
Simple math tells me you will have 3 times the ride time and distance if comparing your 960wh pack to a 3kwh pack over the same terrain.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 8:03am
by TheBMallory
hey,

received the cells and a kweld spot welder (still waiting for the nickel strips). did a test fit and redesigned (again) my pack :
Image Image Image

quick question @Offroader, where did you find a 100A bms that is less than 76mm wide ? I'm thinking about putting the bms on one side of the pack instead with the heatsink toward one of the black metal cover kind of like this : Image
but I know this is not ideal

haven't bought a BMS yet so I'm open to suggestions

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 9:41am
by Merlin
you will not have space on the sides for a bms.
batterys without nickel are 65mm. Frame is 76 without foam to protect battery.

76er frame guys with high power bms put them outside above the controller to the frame.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 10:41am
by madin88
I have used a Daly 20s BMS for a Q76R build:

https://www.aliexpress.com/item/Daly-20 ... st=ae803_4

The dimensions of 120A and 150A version are 150x66x26mm (100A version has a height of 17mm).

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 11:05am
by Merlin
is this DALY 100 continue?
how much peak is your 76 bike using?

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 11:37am
by madin88
Merlin wrote:
Feb 13 2019 11:05am
is this DALY 100 continue?
how much peak is your 76 bike using?
Yes, the 100A version can do 100A continuous (and 200A peak) according to the specs. The Mosfet's used on these Daly BMS are quite good and the wiring seems to be sufficient too for the specified current's.
I have built that 76R for a friend with the 120A version of mentiond BMS and 20s9p battery.. Peak amps?? not that high as the controller is a lame 12F Infineon which peaks at 50-60A.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 3:45pm
by TheBMallory
Thanks ! I just purchased a 120A Daly bms !

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 13 2019 5:47pm
by MJSfoto1956
madin88 wrote:
Feb 13 2019 10:41am
I have used a Daly 20s BMS for a Q76R build:

https://www.aliexpress.com/item/Daly-20 ... st=ae803_4

The dimensions of 120A and 150A version are 150x66x26mm (100A version has a height of 17mm).
Anyone know why the "Common Port" version is slightly more expensive than the "Separate Port" version? I see this same pattern with other AliExpress sellers of BMS's.

Re: Qulbix Q76R Frame Kits & Complete Bikes PRE-ORDER

Posted: Feb 14 2019 5:43am
by madin88
MJSfoto1956 wrote:
Feb 13 2019 5:47pm
Anyone know why the "Common Port" version is slightly more expensive than the "Separate Port" version? I see this same pattern with other AliExpress sellers of BMS's.
Technically seen, on BMS with common charge and discharge port, the discharge current has to flow through two banks of Mosfet's, whereas on BMS with separte ports for controller (P-) and charger (C-), the discharge current just has to flow through one bank. This means they can reduce the number of Mosfet's on the bank for the charge port which would explain the lower price.

common port:
pros: usually identical max allowed charge and discharge currents, protection against overcharge from regen (or charge via controller)
cons: more heat at given discharge current

separte port:
pros: less heat a given discharge current
cons: usually lower max allowed charge current, no protection against overcharge from regen