elmobob
1 mW
NeezyDeezy said:
NeezyDeezy you did extensive diagnostics on my battery? really?? your confusing people in this forum. Are you referring to an issue you're having with your own battery?
I should've read this forum before I bought my battery from sun-
- Thread starter elmobob
- Start date
NeezyDeezy you did extensive diagnostics on my battery? really?? your confusing people in this forum. Are you referring to an issue you're having with your own battery?
arkmundi
10 MW
The order of events is to document what is wrong, then attempt to resolve amicably with the vendor, in writing, so that's documented as well. Give the vendor opportunity to respond. Then, if you're not happy with the vendor response, open a case with PayPal. Their buyer protection is the reason why its better to pay through PayPal, especially if its eBay. PayPal will then give the vendor opportunity. If its not proceeding to your liking, be sure to then escalate it into a "claim." The PayPal jury will then render a verdict for you or the vendor. Remuneration is then immediate if found in your favor. I recently needed to leverage PayPal buyer protection and I won.lester12483 said:
elmobob
1 mW
lester12483 said:
I've spend all afternoon after I got home from work contacting ebay and paypal, looks im SOL, the refund or exchange is at the discretion of the seller at this point because so much time has passed since the sale and the seller states he allows returns only within two weeks, the last resort ebay told me (an actual human being after being on hold for an hour) was to contact my financial institution to claim a refund or try to contact the seller via phone number, I received the phone number but it's disconnected. Paypal kept referring me back to ebay to open up a case. I'll give it a 2 more days and see if he replies to the message I sent him via email.
In the mean time I have a question for you folks, if this battery's capacity is supposedly 20ah, with these cells being unbalanced for who knows how long, even after opening up the pack and balancing it do you think LiFePO4 battery has suffered much degradation? If I do bite the bullet and open up the pack what kind of special charger would I need to charge the individual cell?
arkmundi
10 MW
LiFePO4 cells are nominal 3.3V with max at 3.65V. Some will say 3.7V, but I wouldn't push it. Get a simple single-cell charger in the 3.2V to 3.3V range. Voltphreaks may still be selling them, or find at eBay.elmobob said:
DAND214
10 MW
If you need a charger, I have 2 new a 1 used from Ping.
You will need at least 2 if you are going to balance all the cells.
I paid $8 plus shipping each. let me know if I can help.
Dan
You will need at least 2 if you are going to balance all the cells.
I paid $8 plus shipping each. let me know if I can help.
Dan
dnmun
1 PW
usually it is only one or two cells that are high and cut off the charge so all you have to do is use a power resistor and drain some charge off of the high cell. no need to take the battery apart. no need to use a single cell charger.
don't know why you keep saying that you have to take the battery apart.
no pictures means there is no way to tell you where or what to do.
don't know why you keep saying that you have to take the battery apart.
no pictures means there is no way to tell you where or what to do.
USAEBIKECO
10 kW
elmobob,
Chinese vendors like sun thing sell old battery packs. Who knows how long those cells in the pack have been damaged for. You got scammed.
At this point you could try and sell the pack on this forum to someone with experience swapping the bad cells.
Definitely leave negative feedback on ebay for sun thing. People need to be warned about his defective batteries.
Chinese vendors like sun thing sell old battery packs. Who knows how long those cells in the pack have been damaged for. You got scammed.
At this point you could try and sell the pack on this forum to someone with experience swapping the bad cells.
Definitely leave negative feedback on ebay for sun thing. People need to be warned about his defective batteries.
elmobob
1 mW
dnmun said:
Ok here are the pictures of the battery and current battery voltage readings, I's been plugged in all the time currently reading 38v when disconnected and 44.5v when connected to charger, where do I connect the power resistor and what power resistor exactly do I need, I'll run to radio shack quickly and grab one.
I finally got a reply from sun-thing28 late last night and he said he is going to send me a new BMS board which is what he believes is the issue, that's as far as he is going to go it looks like.
Attachments
elmobob
1 mW
I'll PM youDAND214 said:
dnmun
1 PW
no evidence you need a new BMS or that you need any other charger. nothing is known so when you accepted a BMS from them then you may not have the component needed and have now lost the right to make a claim that the battery has another problem.
all we wanted was a picture of the BMS so we could tell you where to measure things.
all we wanted was a picture of the BMS so we could tell you where to measure things.
elmobob
1 mW
dnmun said:
I lost the right to claim a refund from ebay or paypal at this point because it has been more than 45 days since purchase and because I had made an earlier claim before I received the battery because the post office lost the package but then found it a week later, I got an email from both paypal and ebay stating this, apparently you can only make one claim on an ebay item. Moving on..
The BMS is inside the battery pack. Sorry I thought you mentioned earlier that I did not need to take the battery apart. That's something I'm willing to do at this point. I'll get back with pictures once i'm done opening it to expose the BMS. I might as well turn this into a learning experience. Believe me I've learned my lesson about buying from overseas thru ebay. First bad ebay experience I've had with over 145 purchases since 2006. Past couple of days I've read other forums with people that have been on the same boat as me.
dnmun
1 PW
the BMS is on the end under that white layer. cut the corners of the shrink wrap back diagonally to the corners so just the end is free and remove that white sheet and the BMS is right there.
if there is something wrong with the manufacture of the battery and they are at fault then we have enuff clout to make them fix it. so your ebay/paypal would not matter. there are enuff people here who would contact them, demanding they fix it for you or we would not recommend their batteries, that they could not refuse.
if there is something wrong with the manufacture of the battery and they are at fault then we have enuff clout to make them fix it. so your ebay/paypal would not matter. there are enuff people here who would contact them, demanding they fix it for you or we would not recommend their batteries, that they could not refuse.
elmobob
1 mW
dnmun
1 PW
in the last picture you can see the solder bumps where the sense wire cable plug is soldered to the pcb. that row across the top.
the wire on the far right is the bottom of the first cell, the red one next to it is the top of the first cell, and that is also the bottom of the second cell. so you measure the cell voltage of each of the cells in the series from the bottom cell #1 up to the top of #12. write them down and post them up here. you can do it while charging too. try not to short the solder bumps together with the voltmeter probes.
the wire on the far right is the bottom of the first cell, the red one next to it is the top of the first cell, and that is also the bottom of the second cell. so you measure the cell voltage of each of the cells in the series from the bottom cell #1 up to the top of #12. write them down and post them up here. you can do it while charging too. try not to short the solder bumps together with the voltmeter probes.
elmobob
1 mW
dnmun said:
Exactly 3.2v on all of them, funny thing when I plugged in the charger and touched some parts of the board it turned yellow and charger fan turned on for a few seconds.
dnmun
1 PW
you mean the you were handling the pcb and it started charging?
pull the sense wire plug out and then reseat it to ensure all the pins are in contact and be careful to not damage them doing it.
i thought one cell was dead on this battery and was due for a replacement pouch.
pull the sense wire plug out and then reseat it to ensure all the pins are in contact and be careful to not damage them doing it.
i thought one cell was dead on this battery and was due for a replacement pouch.
elmobob
1 mW
tried reseating the cables, that didnt do it but, squeezing the board together at this point even with gloves on consistently gets the charger to turn on.
dnmun
1 PW
ok, those pins carry the voltage to turn on the transistors used to charge and discharge. i suspect that one of them is not properly soldered or the traces has broken so go look closely and see what is moving that should not be and take close up pictures so we can read those labels and follow the traces.
elmobob
1 mW
dnmun said:
CHECK THIS OUT
so there was one part this part when I touched that was triggering the charger to go on, turned out the blue wire soldered on to the board had too much soldering and a tiny bit spilled onto one of the little channel lines, I scrapped off a tiny hairline using a magnifying glass and box cutter. The battery is now charging happily ever after!!! A few minutes and its already at 39.3V.
THANKS dnmun, YOU THA MAN
Attachments
elmobob said:dnmun said:
CHECK THIS OUT
so there was one part this part when I touched that was triggering the charger to go on, turned out the blue wire soldered on to the board had too much soldering and a tiny bit spilled onto one of the little channel lines, I scrapped off a tiny hairline using a magnifying glass and box cutter. The battery is now charging happily ever after!!! A few minutes and its already at 39.3V.
THANKS dnmun, YOU THA MAN
Damn...that was tricky one. The man is genius. Well done dnmum
Ykick
1 GW
Now you know a little more about how these things work. Buying cheap carries some risks and often "we" must correct poor workmanship that gets through QC. The cost of cheap shit from China...
I highly reccomend getting into power meters, connectors, wiring, etc. That way you can best qualify energy delivery both in & out of a battery system.
Hope you're riding soon!
I highly reccomend getting into power meters, connectors, wiring, etc. That way you can best qualify energy delivery both in & out of a battery system.
Hope you're riding soon!
dnmun
1 PW
you did it, pretty good job to find a tiny short like that. sorry if i was a little too direct for you. just glad you got it working.
USAEBIKECO
10 kW
Be sure to test it out on your bike for at least a week before you declare victory.
dnmun
1 PW
another thing to add to this.
if you have a soldering iron and solder, you can unsolder that big wire and move it over to where it says P- which is where power goes to the controller. so then that connection could be made permanent to the controller so you don't have to disconnect to charge.
then find another wire and solder it where it says C- where the blue wire is now. the charging wire can be very small. 18AWG is adequate. so then you can charge while the battery is connected to the controller.
if you don't have separate wire for the controller circuit current there is a way to install a small DIP or rocker switch on the BMS circuit current to turn the battery off itself when connecting to the controller or if it is in storage for long periods.
if you have a soldering iron and solder, you can unsolder that big wire and move it over to where it says P- which is where power goes to the controller. so then that connection could be made permanent to the controller so you don't have to disconnect to charge.
then find another wire and solder it where it says C- where the blue wire is now. the charging wire can be very small. 18AWG is adequate. so then you can charge while the battery is connected to the controller.
if you don't have separate wire for the controller circuit current there is a way to install a small DIP or rocker switch on the BMS circuit current to turn the battery off itself when connecting to the controller or if it is in storage for long periods.
elmobob
1 mW
dnmun said:
Cool thanks, I'll do that this weekend, just got home from work, about to go n give it a try for a few minutes, right now is exactly at 40V after charging for a few hours last night. 3.33v measured per cell.
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