Ping problem 36V 12ah 2.0 Bulging

[JinbaIttai]

Something must be wrong with my ping battery.

I did my usual routine. Starting on a full charge I rode 3.5 miles up a 100 foot hill and then rode 3.0 miles up an 800 foot hill to get home.

I let it sit uncharged overnight, and then rode back down the hills to work.

When I went to plug the charger in a couple of hours later at work, I noticed the battery bulging at the sides. What used to be a perfect fit was then
a “ stuff” fit in the plastic bin in my bag. I rode it home like that more slowly than usual. It still seemed to have the same amount of power.

I don’t get it. I understand this is a 1C battery. My controller is limited to 24 amps, or 2C. Because I want the battery to last a long time, I’ve developed a habit of always cruising at half throttle or less, constantly pedaling hard enough to share a decent amount of load. I wish I could commute faster, but that’s what I get for buying the smallest battery I suppose.

Even going up the hill, I poke along at 5mph in low gear, half throttle, pedaling away. I have 3 LEDs on the throttle I use as a primitive ammeter. If one of them goes out, I pedal harder (except for a couple of steep spots where I have accepted 2 out of 3 LEDs lit as ok).

I only go full throttle in emergent situations, and then for no more than 10 seconds.


Did I burn my battery out because I pull too much current on a day to day basis?
I have no cycle analyst, but I’d estimate it spends most of its life between 0.5 and 1.5C.

I’m not sure of what to do now; the battery is about 6 months old, put into service less than 3 months, and only has 35 shallow cycles on it (about 7 miles per cycle).

Perhaps I should consider upgrading to 48V 20ah?

Any suggestions?
View attachment P1000054.JPG

 

[Ypedal]

I bet there are broken tabs on one or more cells resulting in the one's left taking a hard load, making them puff ( 4ah cells in paralell right ? ) .. only way to know for sure is to open it up.. :lol: ( take pictures pls ! )

 

[Reid Welch]

Ypedal mentions a question burning my mind: has anyone here, in any thread, shown an unwrappped Ping?


I want to open my new, unused Ping and take pictures.
I do not want to do this if someone else has been there/done that before me.

The problem at hand: I have no idea but it does sound reasonable to suspect that the battery, under warranty,
should be send back on a fast boat to China for Ping's inspection.


Only fools like me open or short or cut connectors or fill with oil,

hub motors or batteries, etc, which have not even yet had a chance to give service.


Good wishes, and sorry for your undeserved bad luck with the 'small' Ping pack.
Mine is 36/20Ah because I am afraid of C rates and hills and watersports (I joke)
and afraid to take apart now, perfectly good new gear such as I have here. (I joke).

---again: Are there any threads showing denuded Ping packs here at Endless Fear Forums?

 

[Jeremy Harris]

Here's a couple of pics of mine, partially split (I separated it into two halves to get a shape that would fit under the seat of my 'bent a bit better):

As it arrived, with charger

With most of the tape off

Top view, before I took the pack apart

BMS board, after I removed the yellow heatshrink

Finished composite battery box

Sorry I don't have any closeups of the cells. Here's what the finished pack looked like after I'd made a composite box and fitted it under the seat of my 'bent:

Jeremy

 

[dogman dan]

On the 12 ah size a 1 c discharge rate would be 12 amps, so I suspect you have done more 2c discharge than you may think, especially since motors tend to get hot and draw more than usual when going up a long hill. But I agree, if one cell tab got disconnected, then you would be riding on a 8 ah battery, and tend to over amp the remaining connected cells. Email Ping for sure, and ask him what he will do, and then look up the ping repair threads in the archives of the ES. While you have some replacement cells coming anyway from ping, it might be best for you to order some more, and make a 20 ah pack out of it. In my opinion, only the 20 ah pack sise has much chance of lasting a long time, unless, 1 you live in real flat terrain, and 2 you have a very low amp bike, like a 10 amp controller.

Reid, there are hours and hours of entertainment reading last springs duct tape threads, where pix are posted on opened packs, and maybe the repair stuff there too.

I hunted a bit, but couldn't find the how to solder on the tabs post. It may be in the duct tape ebay batteries thread but I don't know for sure.

 

[marty]

x
x
x
x
x

Finished composite battery box

Sorry I don't have any closeups of the cells. Here's what the finished pack looked like after I'd made a composite box and fitted it under the seat of my 'bent:
x
Jeremy

Jeremy,
How do you make composite battery box?

 

[Reid Welch]

Jeremy, thank you for those images!

I need links or just to "work" to find by search, old threads of denuded Pings.

Of course, all I plan to do is untape mine, and count the cells and see how they are interconnected,
and make a ton of close-up photos. Then re-tape and water seal.

Noting that Jeremy's Ping BMS is nearly identical to my two.
BMS # One, I fried because I'd un-shrink wrapped the thing, then stupidly shorted playset chain, whilst hanging the bike and tilting,
shorting the chain across, from, negative to positive poles of the naked, uncoated, BMS.

The new BMS, instead of being shrink wrapped, is epoxy encapsulated (see my bike build thread for images?)
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=7454&start=180
epoxy images are seen about half way down the long and silly page.

Noting: when charging, even with the small, OEM charger, the FETs get just warm to the touch.
Epoxy is somewhat of a thermal insulator. So is shrink wrap.
I will not be wrapping this BMS. I may give it a light spray coat of flat black.
It will be mounted (glued or double-sticky taped) to the side of the Ping brick.
And with air-space clearance between the BMS and the wire mesh basket,
those FETs (hardly thermally stressed by charging), will charge very cool.

Likewise, the controller, instead of being a totally sealed box, relying on heat sink of the FET mount to the box
for thermal conductivity; that controller will not only have that feature retained, but it will be an "open box",
in the full blast of rider's air motion, and freely open at the bottom for air and even, water, to splash up in there:
the controller board will be epoxy sealed, as is the new Ping BMS. The controller box, will be OPEN to the elements (cooling air in particular).

Philosophy: forget trying to seal OUT moisture from any sort of container, whenever possible.
Instead, waterPROOF the sensitive electronics (and epoxy is the most waterproof, non-hygroscopic, inert sealant.

We want no terreriums growing lichen, unseen, in a controller enclosure, or BMS shrink wrap, etc.
---
enough of me. I talk too mulch. typo intended :lol:

 

[Jeremy Harris]

Marty,

The box was made using the "lost foam" method. I hot glued two bits of 60mm thick extruded polystyrene foam insulation together (the pink or blue stuff used as house insulation) and just carved it to shape (the outside of the foam becomes the inside of the box).

I covered the foam with brown plastic parcel tape (the 2" wide stuff) then laid up woven glass cloth with epoxy resin over the lower half, leaving the top face uncovered (you have to use epoxy as polyester attacks the foam). Once this had gone hard, I trimmed the edges so they were flush with the uncovered top face and then parcel taped over the newly laid up glass fibre. I then laid epoxy glass over the top and sides (to about half way down the sides) and let that cure.

Once it was all hard, I drilled a hole on the lower half (at the end where the wires come out) and poured petrol (gasoline) in. This melts the foam and the pretty horrible sticky mess runs out (it takes three or four goes to melt all the foam). The two halves of the case then pop apart, with a reasonably good internal finish, due to the shiny surface of the parcel tape.

The last thing to do is to trim the top part edges, fill and sand the outer surface and give it a coat of paint. The top is a tight sliding fit over the bottom, as it was moulded on top of it, with just a thickness of parcel tape as clearance. This makes it fairly watertight, but to be sure I put a wrap of PVC tape around the joint as well.

The longest job was filling, sanding and painting the outside, the actual carving and laminating is pretty quick. I did this because I wanted a box that would fit exactly into the limited space I had. You can use this technique to make pretty much any shape box you like. I've made odd shaped fairings, aircraft fuel tanks and even an inlet manifold for an experimental fual injection system using this technique. You can make the shape as complex as you like, as long as you can get the glass cloth to drape over it OK.

Jeremy

 

[dogman dan]

Awesome box fabrication! I got lucky and found a vintage metal toolbox exactly the right size. As a lifepo4 battery breaks in, it will do more balancing with the bms, which is when the fets get hottest. I found later on the battery charged without as much heat in the bms. I was also worried about this, and put some air space between the bms board and the top of the pack, so if the bms ever does melt, it won't take the top of the pack with it. I'll hunt more for those pack repair links, without the exact name of the thread I'm having trouble finding them.

 

[dogman dan]

Bumped a few threads with pics for you Reid.

 

[likes2bike]

Yeah Jeremy, that's a nice job and a marvelously adaptable and a accessible method you have there. I think I will attempt to do a similar mod to the 48/12 Ping i just got and make an inside the frame mount with some mounting tabs molded in too. This forum: the place to lurk and learn!

 

[JinbaIttai]

Email sent to ping.

I'll let everyone know how it turns out.

As of now I am very grateful I decided to buy from Ping because of his reputation to stand behind his product when there are flaws, since it seems that I am experiencing some flaws.

 

[JinbaIttai]

This is what it looks like with the top zipped off:







I'm pretty certain that purple wire came disconnected when I sliced the top off. In the photos, the lowest left and right corners were bulging from the outside.

 

[JinbaIttai]

I can't tell if the bottom middle cell group is swollen or just the two bottom outer ones.

 

[dnmun]

i disagree about the purple wire. i think it broke under stress caused by the pouches swelling. it looks like the other end of the ribbon cable is restrained and i think it tore off before you opened the pack. in that case you could have had very low cell there because it couldn't balance properly. which was why there was not capacity. i would recommend you first get some slack for those wires on the left end, reattach the purple wire and then recharge. maybe you can get it to charge up again properly and put the tape back on. you may have bad cells there now, but you may get off easy yet.

 

[JinbaIttai]

Well Ping was quick to respond to my emails and is going to take care of me. I won't be able to simply solder in a few more cells to make this one bigger, so I'll have to stick with repairs. Either way, I'm pleased with the customer support.

 

[rguy56]

Ried

Training those turtles to work for you is brilliant!

Bob

 

[paul-home]

I'm afraid my Ping 2.0 36v 16ah failed in a similar way, except I got a fluid leaking as well.
After stripping down the pack, I had 12 swollen cells. I had the pack for about 3 months, it had done about 6 cycles.
Very sad, I had expected better from it.
Ping kindly provided replacement cells.

 

[docnjoj]

Another Ping winner! My 48 volt charger died almost immediately and new one just arrived. Been recovering from trike accident so I havent had a chance to send back the old charger but will next week! Let me tell U when your rear chINWHEEL LOCKS UP IN THE DERAILUER and flips u at 20 mph it hurtz! 6 Broken ribs and a load of road rash! Great!
otherDoc

 

[snowranger]

I wonder what the failure rate is. Most of these posts are about failures. How many Pings are out there?

 

[nomad85]

My ping V1 had a bad cell group after 1100 miles, no swelling, got it replaced(48v20Ah), and the V2 has been fine for 780 miles, it hasn't ever sagged below 47v, even at 75%DOD (I have a 23 amp controller, so it shouldn't sag much, but my V1 sagged quite a bit more)
When you hear about problem with ping's stuff, you always hear good marks for customer service. Good guy to buy from.

 

[dnmun]

i still think you need to solder the purple wire back onto that connector and charge it up. if you did not run the pack below the low voltage limit, i think your pack may still be ok, but the other (gray) wire on the left side is also about to tear off too, so allow more slack for both of them from where the ribbon cable bends over the right side of that pack, charge it up and see what the voltage reads after soldering it together again.

 

[jha07]

I also had a bulged cell and this happened before my first cycle, so I'm pretty sure it's not caused by a high discharge rate.
My pack arrived with with a dead cell group. I had removed the bad group and was waiting for the replacement cells. When the cells arrived, I noticed that the cell closest to the bad group that I had removed was bulged. It wasn't bulged when I took the bad cells out. So this happened during the 2 weeks when i was waiting for the replacement cells.
I told Ping this and he didn't know what caused the cell to bulge, but he did know that the bulged cell needed to be replaced. I was luck Ping sent me an extra cell so I was able replace it along with the other bad cells.

 

[snowranger]

I've got a 48 V 20 ah Ping and noticed that it only charged to 55 volts yesterday, not the regular 60 volts it normally does. It turns out that two cells were at 3.7 volts and the rest were around 3.3 with one at 3.2.

Is it possible that these two cells have less capacity than the rest (i.e. broken tab in parallel group) so that their voltage rises faster during charging? What would you do next?

 

[jha07]

I've got a 48 V 20 ah Ping and noticed that it only charged to 55 volts yesterday, not the regular 60 volts it normally does. It turns out that two cells were at 3.7 volts and the rest were around 3.3 with one at 3.2.

Is it possible that these two cells have less capacity than the rest (i.e. broken tab in parallel group) so that their voltage rises faster during charging? What would you do next?

How long did you leave it on the charger?
It's possible that your pack is just out of balance and if you let it charge longer, the other cells will climb up to 3.7V.
I would leave it on the charge for 48 hours and see if the voltage climbs.