Is Jimmywu66 & EastUnitedMusic the same person?

[dontsendbubbamail]

I went for another ride with my jimmywu battery. Looks like I have another cell going bad. It is time to set this one on the shelf and move on. I took a chance and it turned out to be a expensive learning experience. That is just life. I could do a PayPal dispute, but I don't think it is worth all the trouble. For now I am going back to the lead acids so that I can do a little riding and experimenting. Lithium batteries are still on my list of got to haves, but I am not sure about which flavor of lithium batteries I will chose.

nopingBubba

 

[dnmun]

thatsa bummer bubba, you are down to 10 rows of cells now? i think we knew at least 2 were bad already, i would like for all you guys to be able to go together to ebay and tell them how you got rooked. maybe you guys can form a group to act as a class action to get ebay to act in your favor. there may be other people who have had to fight ebay, go google up 'ebay dispute resolution class action'.

i thought you still had another battery coming from them, i hope you don't have the same problems, but fill us in. also maybe we can resurrect your old battery. are you up to taking it apart? if you have dead cells in one row and can cut them out then maybe you can go through your whole pack and find the dead cells and remove them and then rebuild the pack so it is not as wide as originally, but has the full 16 rows to get to 48V so you can use the BMS to charge. but instead of being 11 cells wide, it might be reduced to 8 cells wide, with the new rows made up of cells lopped off other rows, and tied together parallel to rebuild the missing rows. you just would end up with lower capacity, but 8 wide would still be 7Ah.

it would be worth the education, the hardest part will be keeping track of the sensor wires so they end up in the correct place when the rows are rebuilt, and even that could be figured out later if you lose track of which wire goes to which row. and soldering to the metal straps is difficult, there are plans for a spot welder somewhere on here, maybe you can buy one after someone else uses it, or share. BOL, dennis

 

[Ypedal]

Bubba .. you in Canada or US ?

 

[leamcorp]

Bubba, sorry to hear all your problems. I've certainly had similar experience...

However, after rebuilding the pack, I haven't had any problems. And rebuilding wasn't that difficult (and I'm total electronic noob).

I would suggest that you rebuild the pack, replacing the bad cells, using pings BMS, etc. The repair shouldn't cost too much ($48 for Ping BMS and probably few cells from Batteryspace.com and bit of patient) and probably worth the effort, if not for learning experience. Maybe someone here could take a look at your battery.

 

[rguy56]

This guy is still doing business on eBay. We all know that he has a way of artificially creating feedback, and you can find a clue to it on his eBay store, Lau Chan is still doing business as "mp3hk", with the store name "Power Shop Shop Shop". Check it out! I've told eBay about this guy, but he's still there.

At the top of his store page, right under the store name is this exact quote: "This is not a feedback only service. You are buying an eBook on how to get the quickest positive feedback for the smallest outlay, and within eBay guidance."

I've checked out ebay related scams, and it looks like this seller accidently loaded this line from the resource where he learned how to build illegitimate feedback! One common source (among many others) for the buying and selling of illegitimate feedback is apparently ebooks, where nothing but cash-for-feedback occurs. Nothing else really changes hands.

Paypal has done nothing for me except sending various tasks that have to be completed within three days or they'll cancel the claim, then they extend the deadline. My claim has pretty much been in existence as long as this thread. I really think paypal is going to be of no use, sadly. However, I have also made a claim through my credit card, and there may be some hope...

Bob

 

[Battboy]

So, sorry for your experience, but thank you for documenting it so others will not make the same mistake in trusting ebay vendors without verifying. Before someone attacks me - I qualified my statement!

Don Harmon

 

[dogman dan]

Unfortunately for the original owner I see Link getting his hands on some really cheap round cells to play with in the future. At the very least this kind of pack will need to be rebuilt so you can switch out a cell group sorta easily. Swap out the bad cells with a new set and dork with sorting out the bad cells later.

I totally agree with Don about unverified Ebay vendors. I would never have sent money to china without the positive customer service reports I read about Ping on this forum and on the V. Many of the problems I see with all duct tape batteries seem to be related to too small a pack for the low c rate. Even Pings batteries can be a problem if you buy less than 20 ah. Even that is too small for the big motors.

 

[dontsendbubbamail]

Bubba is just a poor old southern boy living in the great state of North Carolina, USA. It is going to be raining tomorrow and I will be off from work, so I may take another crack at getting that pack working at 36 volts. So far I have one totally dead cell bank that measure 0.3 volts Two more are reading 2.7 volts, while all the others are reading 3.2 volts. The bright side to all this is that my motor was over heating on 48 volts, but it runs cool enough on 36 volts.

Bubba

 

[TylerDurden]

Before someone attacks me - I qualified my statement! Don Harmon

History in the making: I agree with Harmon on this:

A big thanks to the Gineau Pigs in the group. Your pain is the community's gain.

 

[Sacman]

I consider myself one of the lucky Gineau Pigs since I can still use my ductape battery even tho the BMS is dead.

Bubba good luck on your salvge operation. The cells reading 3.2v look hopeful. Just test them under load to check.

 

[R2R2]

I guess I am somewhat of a lucky gineau pig to... at least so far. I've probably gone around 200 miles now on my battery. Despite one cell and my bms going bad, I to am still able to use my battery. I've figured I'm down to 88 of the 96 total cells in the 36 volt 10 ah battery. My charger gets each of the 11 "cells" up to about 3.8 volts which is pretty safe. Once the excess charge is taken off, the cells are back down to about 3.3 volts per cell. I just have to guess how far I can really take my battery. Right now I feel pretty safe with 7 miles. Are there any tell tell signs of when a lifepo4 is nearing its end of charge? I mean it's pretty obvious with a lead acid... one can just tell by the lack of power or juice that it's over for that ride. Does the lifepo4 give any signs or does it just go kuput and ruin cells?

I'm still curious about cutting through the duct tape and getting down to the bad cell but at the same time I'm taking the stance for now that if it ain't broke (or fully broke at least) don't fix it. I have come across some ebay adds selling individual 18650 cells for around $2.60 each. I could buy 8 of these cells for about $21 and be back to where I was but then have to deal with all the soldering that seems like from what I hear isn't all that easy, and, I could possibly really louse things up.

 

[dontsendbubbamail]

Are these jimmywu batteries?

http://www.e-bikekit.com/buy-batteries.html

Bubba

 

[dnmun]

bubba, i think you can ask the seller if they are built from the prismatic pouches like mr ping or if they have the 18650 cylindrical cells. i think the fly by night guys on ebay sell directly through ebay to avoid any warranty claims, which is less likely when the batteries end up resold through a third party. i still recommend the headway group buy, i think you could still buy a battery and get it into the container before they ship. lifepo4-purchase@yahoogroups.com i think is the address.

 

[cammycc]

EastUnitedMusic

http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=eastunitedmusic&ftab=AllFeedback

playgame6969
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=playgame6969&ftab=AllFeedback&myworld=true


jimmywu66
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=jimmywu66&ftab=AllFeedback&myworld=true

The members above is non-registered ebay member..They are related with the ones below:

mp3hk
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=mp3hk&ftab=AllFeedback

free_shopping88
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=free_shopping88&ftab=AllFeedback


leebenmr08
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=leebenmr08&ftab=AllFeedback&myworld=true

Actually the three are same one...We can see there is something ungood with the batteries he selling...
Take care!

 

[oldhaq]

Just some info on the Signalab BMS supplied by Jimmywu et al.
I was able to make out most of the 14 pin IC part number that is scratched off, magnified under bright light.
It reads "CD401_" a CMOS type switch or gate.
the last digit is very hard to read, my guess is either a 4011, 4012 or 4016, as there appears to be 4 sections according to the connecting tracks.

 

[dnmun]

the four functions are?

1: high voltage during the charge, shuts off the charging fet when it goes high., 2: LVC when individual cell voltage drops below x.xxV, 3: over current shut down when voltage drop across shunt exceeds some reference voltage, and 4: maybe the 4th is just to drive the fets or invert the signal to drive the gates, driven 'either' by LVC or shunt high/low signal. you should be able to tell which is which by following the traces into the package

 

[rguy56]

WHOO-HOO!!! PAYPAL IS MY FRIEND AGAIN.

How long has it been? Three months?

Paypal says they are finding in my favour, and will credit me with original purchase price on the two faulty batteries from Lau Chan. He still claims the original batteries were fine in spite of sending me photos of batteries with different wiring being tested, and saying those were the originals. Fortunately, I have many pictures of the ones I had. He may not have personal knowledge that they were repaired before retest, but they were.

(edited: replacement batteries are winging their way back to wuu)

I'm so glad to be done with this guy, and now I can spend my money on a legitimate battery seller. I swear I'll gladly pay quite a premium for a quality seller.

Bob

 

[dogman dan]

 

[leamcorp]

Thats cool Rguy!

As for my battery - after replacing Mr Wu's BMS with Ping's, its working fine.

There was a concern while back about using Ping's BMS (since his battery is rated for 60+v vs 55v) with JimmyWu's battery. I haven't run into any problem in both charge/discharge. I was concern about the charging portion, but capacity of the charger being 55.5v, I don't think BMS really comes into play. Maybe it will be different if I use Ping's charger (which I have) but I'm not willing to risk it at this point.

 

[dnmun]

you should see if there some way to boost your charger output voltage up to 59 volts, mr ping's charger is 61 volts, right? some people have found a variable pot close to the feedback loop for the output voltage. maybe there is a fixed resistor which could be changed to get to 59V.

the BMS will shut down the charging altogether when all the cells are fully charged. that's what that charging fet does.

 

[Sacman]

Nice to hear PayPal is getting your money back Rguy. Thanks for sharing your whole negative experience with Jimmywu66 with us. I learned a whole lot about LiFePO4 batteries, BMS's, chargers and Ebay from this thread.

If your charger is like mine there is no variable adjustments inside to raise voltage. I already looked. I don't believe the higher charger voltage makes any difference anyway for our cylindrical cells battery pack. Reason why I say that is because I have another (different) charger that gets to 59V that I keep at my office. And I don't notice any gains in speed or range when I charge with that charger.

 

[Battboy]

If your charger is like mine there is no variable adjustments inside to raise voltage. I already looked. I don't believe the higher charger voltage makes any difference anyway for our cylindrical cells battery pack. Reason why I say that is because I have another (different) charger that gets to 59V that I keep at my office. And I don't notice any gains in speed or range when I charge with that charger.[/quote]

There is a reason to use a charger that is designed for LiFePO4. One is to have the higer voltage needed to "completely" charge the cylindrical cells, and second smart enough to hold the voltage and then drop it back to a trickle charge for the remaining charge curve to completely charge LiFePO4 and finally to shut itself OFF once complete. Doing it with other chargers you run the risk of cooking your cells or never acheiving a "balanced charge" which over time you will end up with an unbalanced pack. Sorry but that's the real story why a proper charger is recommended for LiFePO4.

Don Harmon

 

[Sacman]

These ARE LiFePO4 chargers with 3-stage charging: constant amps, constant volts, then trickle. But there was really no question that our charger were for LiFePO4 batteries or not. I was commenting more in regards to the higher charging voltage was not really necessary.

The idea of a higher charging voltage being possibly better came earlier on this thread when we discovered Ping was selling LiFePO4 chargers at 61V. The Jimmywu/Mr.Lau/EastUnitedMusic LiFePO4 chargers that me, Rguy and others here got are only 56V. So many guys here (including me) thought our chargers weren't charging high enough and felt we were sold a deficient charger.

But later on in this thread we discovered that Ping batteries are constructed differently from JimmyWu/Mr.Lau/EastUnitedMusic batteries and that was the reason for the difference in charger voltage. So it turns out that 56V was appropriate and enough for our JimmyWu/Mr.Lau/EastUnitedMusic batteries since these packs are made from cylindrical cells which had a lower nominal voltage (3.5V/cell) and are quite different from the the Ping batteries which were made from prismatic cells and have a higher nominal voltage (3.8V/cell).

 

[dnmun]

no difference in the chemistry so the total state of charge will be dependent on the final charge voltage. lipo is different, manganese, and other cobalt chemistry is all different, but lifepo4 is all the same chemistry, cell type should not make a difference , imo. you can use the open source BMS gary is finishing up to charge any lifepo4 cell, whether prismatic or cylindrical, to 3.65V. that's why mr ping's BMS would work on other battery packs too as long as they are lifepo4. in fact the jimmy wu BMS that doesn't work which now appears to be a knockoff of the ping signalab pcb, and is trash because the parts and workmanship is inadequate.

all jmho.

 

[dogman dan]

As Don rightly points out, these duct tape pack chargers are really just sla chargers with the voltage tweaked. I am though, skeptical that it is all that harmfull to use them since they are such weak output chargers to begin with. Leaving lifepo4 on a trickle charge at higher amperages on bigger packs may be a different story. We just have to wait to see, on reaching 1000 cycles. At the rate I'm going, I'm looking at allmost 3 years to get there. Right now I'm at aprox 200 cycles in six months, I leave my pack on trickle for hours and hours since I sleep through the end of the charge cycle, and my Ping v 1.0 is doing perfectly, with no measurable loss in capacity. Good cells last fine with the cheap chargers. With the dumpster 18650 's well, my sympaties to you all. Hopefully you will be able to weed out the junk cells and still have something usable.

One thing I am curious about though, does the jimmywu pack rest at the same voltage regardless of the charger used? If so, you may still be getting the benefit of more ,or at least quicker balancing by using the higher voltage charger. In my case, before I ruined my Ping charger, my pack rested at about 45v after charging at 46.5. Once I started using sla chargers that put out 44.5v, the pack rested at 44.5v. It stilll stayed balanced though the whole thing, and now I have a charger tweaked to 47v and the pack rests at 45v.