how to interpret this data? something is not working

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want to build

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May 18, 2018
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Hi
2 years ago i did this soldering test battery prototype. it has been laying with bms plugged in for 2 years.
the battery was made with some ok not perfect used vtc4 and vtc3 cells. 13 2p. 13 of each

this week i tried to plug my xiongda and controler(i think it is a kt not sure) . i plugged all the wires i had and was left with this white plug that i dont know what im supposed to plug in. i also plugged the pas sensor even if it is not installed on the bike..
Anyway, i charged the battery to 100pourcent at 1. and it was around 40 volt.

the motor is not moving.anyone knows why? is it a battery probleme or attachement or maybe a part is broken?..
i took those picture that give some data while it was plugged to the motor and battery.

tx

https://imgur.com/gP2jlqd
the 2 pin white is the only thing that is left unused .What does it serves for? is the reason why nothing works?
here is what i can see.

https://imgur.com/HZalhvO

https://imgur.com/NxdDt1u

https://imgur.com/PKE39SG

https://imgur.com/Tnx2mjH

https://imgur.com/zPp8VAv
https://imgur.com/YET1qK7
https://imgur.com/FqZjlC8

what to conclude from those info? sorry some are repetitive but not all
 
presume this first time used this controller, is it new ? do you have a throttle ? if so how many wires?
should be 3 , if not then white probably goes there, not sure of specs on your cells but think fully charged should be more like 52 for a 13s screen says 39v so that not good , what voltage is your charger ? could the pack be so out of balance BMS is shutting of straight away? need to do a voltage check on each parallel, has this motor worked for you before ? are your phase wires correct order? do you have motor cut of on brake is wires correct, maybe do a picture how you wired controller ,lots of questions I know but all reasons wheel no go :mrgreen:
 
Just troubleshoot one thing at a time.

As mentioned in the other thread (crosslink?)

I'd start with that battery pack.

13S is nominal 48V, around 50% SoC.

It should get up to 53-54V charging, hold it for a while, then it should not drop much at all.

Put a small load on it, say a few light bulb whatever, at 1-2A

The voltage should hold above 50V for quite a long time.

If not, get a new pack going, at least ordered. This time use brand new cells from a trusted source, and take care of it properly, not just ignoring it for months at a time, especially when it's not being cycled.
 
Greendog said:
presume this first time used this controller, is it new ? do you have a throttle ? if so how many wires?
should be 3 , if not then white probably goes there, not sure of specs on your cells but think fully charged should be more like 52 for a 13s screen says 39v so that not good , what voltage is your charger ? could the pack be so out of balance BMS is shutting of straight away? need to do a voltage check on each parallel, has this motor worked for you before ? are your phase wires correct order? do you have motor cut of on brake is wires correct, maybe do a picture how you wired controller ,lots of questions I know but all reasons wheel no go :mrgreen:
Click to expand...

presume this first time used this controller, is it new yes?
do you have a throttle thumb yes? if so how many wires? 3These are the only wire wich color dont mach apart from the break that the color dont mach neigther.
should be 3 , if not then white probably goes there, not sure of specs on your cells but think fully charged should be more like 52 for a 13s screen says 39v so that not good ,
what voltage is your charger ? Dc out put 54.6

could the pack be so out of balance BMS is shutting of straight away? I dont know need to do a voltage check on each parallel, they all show 3.5 apart from 2 parallele group where i can only read 0 readings


has this motor worked for you before ?
Never tested it is new
are your phase wires correct order? The color match each other
do you have motor cut of on brake is wires correct,they are electric brake so i imagine they have a cut off
maybe do a picture how you wired controller ,lots of questions I know but all reasons wheel no go :mrgreen:
could the unused 2 pin red black be a speed controler?
when i press the truttle the display turns to say number 3 and on the right info.
https://imgur.com/a/lfRVkLX
image 1 is the what i beleive trottle unmatching color.
image 2 are break i beleive also not matching
3 is what the battery look like
4 is the controler attached only one 2 pin red and black that i dont know what is for..https://imgur.com/gP2jlqd
 
here is the post where i need help
tx

https://endless-sphere.com/forums/viewtopic.php?f=14&t=113146&p=1673409#p1673409
 
Have you done objective testing on the pack yet?


https://endless-sphere.com/forums/viewtopic.php?p=1673019#p1673019

If the pack does not pass, just replacing the worst cells is only going to kick the can down the road.
 
john61ct said:
Have you done objective testing on the pack yet?


https://endless-sphere.com/forums/viewtopic.php?p=1673019#p1673019

If the pack does not pass, just replacing the worst cells is only going to kick the can down the road.
Click to expand...
hi what do you mean by objective testinG? does taking the voltage of parallel group is sufficient testing?
they all show 3.5 apart from 2 parallele group where i can only read 0 readings

could you rephrase this , im still learning english tx just replacing the worst cells is only going to kick the can down the road.
 
by want to build » Aug 31 2021 8:28am

john61ct wrote: ↑Aug 31 2021 12:12am
Have you done objective testing on the pack yet?


viewtopic.php?p=1673019#p1673019

If the pack does not pass, just replacing the worst cells is only going to kick the can down the road.
Click to expand...
hi what do you mean by objective testinG? does taking the voltage of parallel group is sufficient testing?
they all show 3.5 apart from 2 parallele group where i can only read 0 readings

could you rephrase this , im still learning english tx just replacing the worst cells is only going to kick the can down the road.
Click to expand...

Having two groups reading 0V means your battery should not be used any more.
"kick the can down the road" Means that your not fixing the problem, just getting getting a little more time.

Think of a air leak in tire. you can put more air in it but does not fix the leak.

Hope that helps.
 
I gave you a link to my post in the old thread with specific suggestions.

Ask there if you are unclear on any details

Voltage by itself tells very little
 
john61ct said:
I gave you a link to my post in the old thread with specific suggestions.

Ask there if you are unclear on any details

Voltage by itself tells very little
Click to expand...

hi
the link when i click it brings me back to how to interpret this data? something is not working is this what youre talking about?
 
want to build said:
john61ct said:
I gave you a link to my post in the old thread with specific suggestions.

Ask there if you are unclear on any details

Voltage by itself tells very little
Click to expand...

hi
the link when i click it brings me back to how to interpret this data? something is not working is this what youre talking about?
Click to expand...

i feel confused about what you are directing me at since you wrote couples of messages can you paste it ?
 
ZeroEm said:
by want to build » Aug 31 2021 8:28am

john61ct wrote: ↑Aug 31 2021 12:12am
Have you done objective testing on the pack yet?



viewtopic.php?p=1673019#p1673019

If the pack does not pass, just replacing the worst cells is only going to kick the can down the road.
Click to expand...
hi what do you mean by objective testinG? does taking the voltage of parallel group is sufficient testing?
they all show 3.5 apart from 2 parallele group where i can only read 0 readings

could you rephrase this , im still learning english tx just replacing the worst cells is only going to kick the can down the road.
Click to expand...

Having two groups reading 0V means your battery should not be used any more.
"kick the can down the road" Means that your not fixing the problem, just getting getting a little more time.

Think of a air leak in tire. you can put more air in it but does not fix the leak.

Hope that helps.
Click to expand...
well since all the rest of the groups show 3.5v if i replace the 4 cells, would that solve the problem?
why do you say that there seems to be an inherent problem (like a leak) with my battery? if i redo the soldering around those cells does that solve the problem you see (that i still dont understand?) plz explain tx for my understanding
 
by want to build » Aug 31 2021 5:54pm

ZeroEm wrote: ↑Aug 31 2021 11:40am
by want to build » Aug 31 2021 8:28am
john61ct wrote: ↑Aug 31 2021 12:12am
Have you done objective testing on the pack yet?



viewtopic.php?p=1673019#p1673019

If the pack does not pass, just replacing the worst cells is only going to kick the can down the road.
Click to expand...
hi what do you mean by objective testinG? does taking the voltage of parallel group is sufficient testing?
they all show 3.5 apart from 2 parallele group where i can only read 0 readings

could you rephrase this , im still learning english tx just replacing the worst cells is only going to kick the can down the road.
Click to expand...
Having two groups reading 0V means your battery should not be used any more.
"kick the can down the road" Means that your not fixing the problem, just getting getting a little more time.

Think of a air leak in tire. you can put more air in it but does not fix the leak.

Hope that helps.
Click to expand...
well since all the rest of the groups show 3.5v if i replace the 4 cells, would that solve the problem?
why do you say that there seems to be an inherent problem (like a leak) with my battery? if i redo the soldering around those cells does that solve the problem you see (that i still dont understand?) plz explain tx for my understanding
Click to expand...

All these nested quotes are getting hard to read. I was trying to help, does not looks like i'm making it worse.

I will get back to the basics:

You have cells groups at 0V. The battery needs replaced.
It is dangerous to use as it is. To repair it would cost more money and time than it is worth.

If you just want to learn how to work on batteries there are many threads on testing cells and building batteries.
 
want to build said:
john61ct said:
I gave you a link to my post in the old thread with specific suggestions.

Ask there if you are unclear on any details

Voltage by itself tells very little
Click to expand...

hi
the link when i click it brings me back to how to interpret this data? something is not working is this what youre talking about?
Click to expand...
The link should be going directly to my post #3 of that thread.
 
Deleted
 
totally get wanting to build bike with minimum expenditure , but somethings are worth spending on,
a good battery is the heart of a nice ebike , 2p pack of different cells not great ,I'd put cost of repair towards a new pack with plus points not having do soldering and increased safety of new pack also more power and range = more fun :mrgreen:
 
y john61ct » Aug 31 2021 8:11pm
The link should be going directly to my post #3 of that thread.
Click to expand...
Just looking for a short cut to fix the battery, anything else is ignored.

if i replace the 4 cells (and then) if i redo the soldering around those cells does that solve the problem
Click to expand...

I'm no mind reader, seems like a suggestion that the cells are ok and the connections are bad.
 
Greendog said:
totally get wanting to build bike with minimum expenditure , but somethings are worth spending on,
a good battery is the heart of a nice ebike , 2p pack of different cells not great ,I'd put cost of repair towards a new pack with plus points not having do soldering and increased safety of new pack also more power and range = more fun :mrgreen:
Click to expand...
it is a test battery mostly to test my new motor and how it goes up the hills.
changing the 4 cells would be less than one hour. it know it would be a tiny capacity but it is a test to also tels test my setup on bike and wiring. ... so since i already have 4 spare cell do you think replacing them would allow me to have a tiny workable battery?
 
by want to build » Sep 01 2021 6:16pm
it is a test battery mostly to test my new motor and how it goes up the hills.
changing the 4 cells would be less than one hour. it know it would be a tiny capacity but it is a test to also tels test my setup on bike and wiring. ... so since i already have 4 spare cell do you think replacing them would allow me to have a tiny workable battery?
Click to expand...

You keep asking the same question looking for a different answer. The answer is you need to rebuild the battery. At the very least take it all apart and test all the cells and go from there. If 4 are dead then more are sure to follow soon.

Wanting to do it No matter what people tell you. Let us know how it turns out. :|
 
ZeroEm said:
by want to build » Sep 01 2021 6:16pm
it is a test battery mostly to test my new motor and how it goes up the hills.
changing the 4 cells would be less than one hour. it know it would be a tiny capacity but it is a test to also tels test my setup on bike and wiring. ... so since i already have 4 spare cell do you think replacing them would allow me to have a tiny workable battery?
Click to expand...

You keep asking the same question looking for a different answer. The answer is you need to rebuild the battery. At the very least take it all apart and test all the cells and go from there. If 4 are dead then more are sure to follow soon.

Wanting to do it No matter what people tell you. Let us know how it turns out. :|
Click to expand...

I just want to make something that makes sense. if the 11 out of 13 parallel group are showing exactly 3.5 my reasonning is that those 11x2 22 cells are in good shape. is this reasoning correct? if so they can be left untouched

now for the 2 parallel groups showing 0 volt is there a way for me to discover if the problem was the cell themselfs or a bad connection soldering ?
 
Voltage means almost nothing.

If you want to futz with it, test using my #3 post to see whether or not you wasted your time.

Keep doing it to see if its health is declining.

Ideally you would do it for each cell before re-assembling your pack, and

more precisely with a proper CC dummy load.
 
You would know if you tested the Cells. If not it's a guess.
I don't see what the issue is. If your going to solider them again take them out and test them.

Messing around with bad cells and try to use them will cause a fire. But nothing I say or anyone else is going to convince you of this until you have one.
 
ZeroEm said:
You would know if you tested the Cells. If not it's a guess.
I don't see what the issue is. If your going to solider them again take them out and test them.

Messing around with bad cells and try to use them will cause a fire. But nothing I say or anyone else is going to convince you of this until you have one.
Click to expand...

hi
before building the battery i did select the cell that had voltages not decreasing much over time. they are vtc4 and vtc3 cell sony from dr bass so i feel they are good quality cells.

what makes you beleive that the 11 parellel group that show 3.5 v are bad cells?
 
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