Thoughts on possible bad "shark" pack

Batteries, Chargers, and Battery Management Systems.
User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Thoughts on possible bad "shark" pack

Post by EVTodd » May 19 2016 7:38pm

I decided it might be a good idea to switch my wife's bike's battery pack over to something a little easier for her to take care of herself. We've been using lipo for several years without issue but I wanted something she could just plug in when she's done with the bike without having me do it (the real reason. lol).

I ended up buying a 36v 10ah "shark" pack (Panasonic cells) from a seller here in the states hoping to avoid quality issues from Chinese sellers. We got the battery in February and she has only gone on around 4 or so rides being gentle with it to break the cells in. Anyway, last night I noticed that the green light comes on the charger very quick. This is after an 8 mile ride. I would say it was plugged in less than 1/2 an hour. So I pull out the 'ol multimeter and the overall resting voltage is 39.7v. Hmmm. Shouldn't it be much closer to 42v on a fully charged pack? I'm going to assume it has a dead cell(s).

On a side note, when you plug the charger into the pack there's quite the spark. And before someone asks, I plug the charger into the battery first then into the wall. Is the spark in indicator of something wrong? None of my other packs do this.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
dogman dan   100 GW

100 GW
Posts: 35637
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Thoughts on possible bad "shark" pack

Post by dogman dan » May 20 2016 6:08am

Charges too fast can often indicate something in there is not taking a charge. But look at the plugs, it can also indicate the wire broken leading into a plug.

I thought you were supposed to plug the wall, then the pack. the spark is the pack filling the charger. There is no inrush limiter on the DC side.

999zip999   100 GW

100 GW
Posts: 9463
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: Thoughts on possible bad "shark" pack

Post by 999zip999 » May 20 2016 1:41pm

Check charger for 42 volt. Pack charge should 41.5 volt about. What did you get it.

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » May 21 2016 2:12pm

999zip999 wrote:Check charger for 42 volt. Pack charge should 41.5 volt about. What did you get it.
Charger seems to be putting out the correct voltage. I believe I got it in late February. Seller said it had just been built with fresh cells. He's actually being very helpful so we'll see how it goes.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

999zip999   100 GW

100 GW
Posts: 9463
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: Thoughts on possible bad "shark" pack

Post by 999zip999 » May 21 2016 3:21pm

Im interested in capacity.

alfantastic   10 kW

10 kW
Posts: 522
Joined: Mar 29 2011 10:34pm
Location: UK
Contact:

Re: Thoughts on possible bad "shark" pack

Post by alfantastic » May 21 2016 7:09pm

I've got a similar pack and I always plug the charger into the wall, then charger lead into battery. That way there is zero spark.

I wonder if with all this sparking on the connections, that you've tarnished the contacts and created a poor connection. Try cleaning both the charger output plug and battery input socket with some contact cleaner.

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » May 21 2016 8:35pm

alfantastic wrote:I've got a similar pack and I always plug the charger into the wall, then charger lead into battery. That way there is zero spark.

I wonder if with all this sparking on the connections, that you've tarnished the contacts and created a poor connection. Try cleaning both the charger output plug and battery input socket with some contact cleaner.
This battery has around 4 charges on it. There's zero corrosion on either plug. It's odd. I have 3 packs like this and two came with instructions to plug into the battery first and everyone here is saying that's wrong. This is the only pack that sparks. But I don't think that's the immediate problem. Seller offered a replacement pack so they seem to be standing behind their product which is great.

Capacity wise it's a 10.4 (I think) ah battery. I'm also curious about it's current capacity. Might go for a ride tomorrow and try to get some numbers.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
dogman dan   100 GW

100 GW
Posts: 35637
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Thoughts on possible bad "shark" pack

Post by dogman dan » May 22 2016 6:57am

If you are getting that spark, then the charger you got with it is definitely not designed to handle the in rush when you plug in the DC first.

the problem could be the charger,, defective causing a large spark, or the spark caused a problem.

These are wild guesses btw. I don't know shit about your particular charger.

But in general, the best for both charger and bms is to energize the charger from the AC side, where there is an inrush limiter to keep the charger parts from filling too fast for their own good. Similarly, the circuit in your BMS is designed to receive power slowly, not to have power rush out of it. So when you plug into charger first, it puts a rush of current through the bms, backwards.

Having said that,, I've done it wrong so many times,,,, not particularly caring, or seeing any big sparks, or having any problems.

999zip999   100 GW

100 GW
Posts: 9463
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: Thoughts on possible bad "shark" pack

Post by 999zip999 » May 22 2016 12:32pm

I have put together many types of commercial ebikes and some have instructions to plug in battery first some say wall first.

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » May 22 2016 12:56pm

I hear ya. Actually it does make sense to plug it into the wall first. Really though. That should be something that really doesn't matter. They can't expect a regular consumer to even think about that when they're plugging it in.

I really didn't mean for the thread to turn into a discussion on how to plug the battery in. The big issue is that it isn't charging to full. Bad BMS or cell(s) from the look of things.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

2old   100 kW

100 kW
Posts: 1238
Joined: Jul 19 2014 3:20pm
Location: Socal

Re: Thoughts on possible bad "shark" pack

Post by 2old » May 22 2016 1:57pm

Not to add to something that you don't want to amplify, but I asked the "same" (I think) vendor about order of "plugging" and AIR he said that it doesn't matter. See a very little spark when I plug in the battery to charger first. Getting good value from my 52V, 10 a/h battery. Agree with you that it's probably a bad cell(s) since the charger is putting out the correct voltage.

999zip999   100 GW

100 GW
Posts: 9463
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: Thoughts on possible bad "shark" pack

Post by 999zip999 » May 22 2016 2:39pm

Could be loose sense wire. Check the ez free stuff first. Bad solder joints ect.
Check parallel cell voltage.
1. 3.95v
2. 3.85v
3. 4.01 v

10. Xxx volts.

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » May 24 2016 9:36pm

Welp. It looks like I might be testing some stuff to figure it out myself now. I attempted to ship this via UPS then Fedex figuring I would be honest and say what the contents were and maybe pay an extra hazardous fee or something. No go. They both said it was too big of a lithium battery to ship. I imagine even worse if they think there might be something wrong with it. I guess all of the sellers are just leaving out the fact that they are shipping big batteries when they package them up.

I'm about ready to switch back to lipo already. Thousands of miles on them and I've had one bad cell the entire time. I buy what I thought was a quality premade battery and dang, first one has something wrong with it.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 19 2016 3:39pm

Ok guys. After trying again to ship the battery back with UPS and Fedex both telling me I can't ship it I decided to crack the case open and take a look inside. The first thing I noticed is that it has Samsung cells. I had just purchase another pack and had that confused. Anyway...

I measured each bank of cells. The first one measured 4.11 and the rest measured 3.96. That got me thinking that there is something wrong with the bms so I started looking at the balance leads.

I've been using lipo for years so this may be a stupid question. If you look at the photo you'll notice that the 2 white balance leads (closest to you in the photo) are both going to the same cell bank (positive and negative on same cell). Does that make sense? Shouldn't each lead go to the positive side on one bank of cells like the rest on this pack? Again, sorry if that's a stupid question.
balance leads.jpg
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
friendly1uk   10 MW

10 MW
Posts: 2282
Joined: Mar 14 2013 1:18pm
Location: The not so UK

Re: Thoughts on possible bad "shark" pack

Post by friendly1uk » Jun 19 2016 7:02pm

I don't see a problem with the connections. One wire goes to the top of cell group 10, and the other goes to the bottom, yes. The bottom of group 10 is also the top of group 9. So you have a wire on the top of 10 and a wire on the top of 9. Which is the bottom of 10. Yes?


lots of 4s and a 4.1 looks suspect. Measure again to see if that 4.1 is dropping. It may of been over 4.2 and stopped the charge.
bmsbattery sent me broken and incorrect stuff, and won't even talk to me about it.

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 19 2016 8:05pm

friendly1uk wrote:I don't see a problem with the connections. One wire goes to the top of cell group 10, and the other goes to the bottom, yes. The bottom of group 10 is also the top of group 9. So you have a wire on the top of 10 and a wire on the top of 9. Which is the bottom of 10. Yes?


lots of 4s and a 4.1 looks suspect. Measure again to see if that 4.1 is dropping. It may of been over 4.2 and stopped the charge.
Gotcha on the wiring but that's the only group that's wired that way. Seemed odd that the wire for group 9 was soldered to the negative of the same cell that has another balance lead for group 10 on the positive side of the cell. Again, I probably have no idea what I'm talking about.

The 4.1 group doesn't drop at all. This pack has been sitting for over a week and everything is exactly the same as hot off the charger. Group 1 is reading 4.11 volts and 2-10 are reading 3.96. Do you think it's bad cells? It's odd that it charges to exactly the same voltage every single time and just stays there.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
Ypedal   100 GW

100 GW
Posts: 12524
Joined: Dec 27 2006 12:55pm
Location: Moncton NB, Canada
Contact:

Re: Thoughts on possible bad "shark" pack

Post by Ypedal » Jun 19 2016 8:13pm

the highest voltage group is likely hitting 4.20v first and causing the bms to shut down before the other groups get to full, plug in the charger and test the groups while the charger is working to confirm.
ES site status page:
http://www.ypedal.com/ES/ES.htm
----------------
http://www.ypedal.com

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 19 2016 8:21pm

Ypedal wrote:the highest voltage group is likely hitting 4.20v first and causing the bms to shut down before the other groups get to full, plug in the charger and test the groups while the charger is working to confirm.

I will discharge the battery a bit and try that out. I'm sure that's exactly what's happening. Assuming that's the case what can I do to fix the problem? Is it a bad bms causing it or were the cells just really unbalanced when they built the pack. Remember, this pack has been exactly like this since new.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
Ypedal   100 GW

100 GW
Posts: 12524
Joined: Dec 27 2006 12:55pm
Location: Moncton NB, Canada
Contact:

Re: Thoughts on possible bad "shark" pack

Post by Ypedal » Jun 19 2016 8:28pm

could be a number of things, but my best guess is a weak cell in that highest voltage group, less capacity means it hits 3.0v first, and also 4.20 first... bench test will confirm ..

If.. " IF " you are lucky and the other groups hit 3.0v first, then it's a balancing issue and easily corrected . ... but this is unlikely.
ES site status page:
http://www.ypedal.com/ES/ES.htm
----------------
http://www.ypedal.com

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 19 2016 8:37pm

Ypedal wrote:could be a number of things, but my best guess is a weak cell in that highest voltage group, less capacity means it hits 3.0v first, and also 4.20 first... bench test will confirm ..

If.. " IF " you are lucky and the other groups hit 3.0v first, then it's a balancing issue and easily corrected . ... but this is unlikely.
Just my luck. First "made in the USA" ebike purchase and it's crap. Lol. Just my luck. Oh well, I'll do more testing on it when I have time.

Thanks for all the help!
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 22 2016 7:56pm

eTrike wrote:What Ypedal said is probably the case. I had the same issue recently with positive most cell hitting full charge while others were much lower, BMS is ~$25 and about 25+ days of shipping...

I'd bet the cells are just fine though. Got a hobby charger to test and balance with?
I thought the seller of this battery was being pretty good about it until I finally explained that I couldn't find a way of sending it back to them. Now there's zero communication. Jeez. I was hoping to buy a new BMS from them. No reply. Trying to find decent suppliers in this industry is almost impossible.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 25 2016 8:48am

Anyone on here know who owns Enhancedcycles.com? Just curious if it's an ES member. Did a search but can't find a single post about them.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
teklektik   10 GW

10 GW
Posts: 4020
Joined: Mar 26 2011 1:15pm
Location: CT, USA

Re: Thoughts on possible bad "shark" pack

Post by teklektik » Jun 25 2016 11:06am

EVTodd wrote:First "made in the USA" ebike purchase and it's crap.
EVTodd wrote:I thought the seller of this battery was being pretty good about it until I finally explained that I couldn't find a way of sending it back to them. Now there's zero communication. Jeez. I was hoping to buy a new BMS from them. No reply.
Unfortunately, you've not identified the vendor to help other ES members make informed decisions...
What makes you think the pack was made in the USA? Don't confuse USA resellers who buy or have their packs made elsewhere (China). I don't know of any US-manufactured ebike battery packs except AllCell.

The best kind of product support is the kind you never need to use...
EVTodd wrote:Trying to find decent suppliers in this industry is almost impossible.
Not really. Trying to buy a quality product for super cheap is, though.

For a BMS, email BesTech Power for a quote. A respected supplier here on ES with top quality BMSes.

If you need a battery to get the wife on the road while you fiddle with this one, give a look at EM3EV, perhaps one of the oldest and most respected battery manufacturer/sellers known on ES - a long time ES member (cell_man). Paul is an English guy with a pretty advanced battery manufacturing facility in Shanghai.
Visit Grin Technologies at www.ebikes.ca
Build Thread: 2WD Yuba Mundo V4

User avatar
EVTodd   10 kW

10 kW
Posts: 956
Joined: Oct 17 2007 7:15pm
Location: Illinois

Re: Thoughts on possible bad "shark" pack

Post by EVTodd » Jun 25 2016 12:57pm

teklektik wrote:
EVTodd wrote:First "made in the USA" ebike purchase and it's crap.
EVTodd wrote:I thought the seller of this battery was being pretty good about it until I finally explained that I couldn't find a way of sending it back to them. Now there's zero communication. Jeez. I was hoping to buy a new BMS from them. No reply.
Unfortunately, you've not identified the vendor to help other ES members make informed decisions...
What makes you think the pack was made in the USA? Don't confuse USA resellers who buy or have their packs made elsewhere (China). I don't know of any US-manufactured ebike battery packs except AllCell.

The best kind of product support is the kind you never need to use...
EVTodd wrote:Trying to find decent suppliers in this industry is almost impossible.
Not really. Trying to buy a quality product for super cheap is, though.

For a BMS, email BesTech Power for a quote. A respected supplier here on ES with top quality BMSes.

If you need a battery to get the wife on the road while you fiddle with this one, give a look at EM3EV, perhaps one of the oldest and most respected battery manufacturer/sellers known on ES - a long time ES member (cell_man). Paul is an English guy with a pretty advanced battery manufacturing facility in Shanghai.
Actually, I believe my last message did kinda say who the vendor was. And my intent wasn't to call them out. I'm hoping to contact them here on ES just in case they might have an email issue or whatever. They did actually tell me to send the battery back to them. But... Right now I'm glad I didn't, it would have sucked to have them get it and then stop talking to me. And... I have been told by Fedex and UPS twice that I can't ship it even by ground since it's a defective battery. My big problem with the whole thing now is that they can't even reply to one simple question. Sorry, that's terrible customer service. I assumed since they wanted to fix it they might have a BMS they could sell to me or at least point me in the right direction. I've never asked them for anything for free btw.

Yes, I realize many US sellers are just buying packs from China. After conversations with this seller, it sounded as though they built the pack. They told me when it was built and they were planning on fixing it so I guess it's an easy assumption. I suppose I could be wrong. There's only one seller building packs? I thought Luna (who I wish I would have purchased this from) and some others were putting them together here in the states. I know they don't build the parts (cells, cases, etc...) but no one is getting the stuff and putting them together? That's surprising to me.

And yup, I already know I should have done more research on here before buying. Either way, I guess my point was that I was trying to give my money to a US seller.

I actually don't shop for the cheapest ebike products. I used to but these days I'm looking for reliability over price and I frankly don't need to now. Yeah, this wasn't the most expensive pack but you would expect more than 20 miles or so out of it.

Thanks for the link for the BMS. I will check that out. I'm good on batteries at the moment too I'm just hoping to get this one going instead of throwing that money down the toilet.
New Tidalforce friction drive build: http://endless-sphere.com/forums/viewto ... 28&t=28029

My Friction Drive Outrunner Setup: http://endless-sphere.com/forums/viewto ... &start=330

User avatar
tomjasz   10 GW

10 GW
Posts: 4228
Joined: Mar 29 2014 1:45pm
Location: Out riding, MN USA
Contact:

Re: Thoughts on possible bad "shark" pack

Post by tomjasz » Jun 25 2016 2:08pm

No one to my knowledge is building cased batteries in the USA. It's all a matter of getting the right Vendor who'll work with the buyer. Luna will send new parts. I have a charge port being replaced. AS to shipping back, I use my Amex card for best coverage of purchase when possible, and just ship the battery ground as bike parts. The whole bullshit shipping problem has little to do with quality 18650 cells. Again we have regulations that are a blanket coverage of ALL lithium because of isolated problems with unstable chemistries. Pack it and ship it. Just ship it ground and use UPS. STFU and ship. That said there are good sources for 36V BMS that can be found in the thread like ultimate repository here. To hell with Besttech, they sell some junk too. And at inflated prices and a 2 part MOQ to boot.

https://endless-sphere.com/forums/viewt ... repository
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

Post Reply