1st Ever Ride on LiPo !

[GGoodrum]

Hmm... Bummer about the bad cell. Make sure it's not a broken wire.

On the 4-in-1 charger, would you do me a favor and check to see if the grounds are common on all four outputs? The reason I ask is because the single Accucel-6 charger 50W has a non-isolated output (input and output negative terminals are common...) so I can't use two of them in series, using a common 12V supply. If this 4-unit model uses the same 50W design as a base, the inputs would be common, which means you wouldn't be able to use it to charge a 12s, 18s or 24s series connected pack.

-- Gary

 

[Ypedal]

Would a picture of the insides show what you need to know ? :lol: I"m willing to open it up, no worries there.. :wink:

 

[Ypedal]

And about the bad cell, i've been wanting to open one of these up for an inspection, perfect opertunity, too late tonight but tomorrow in the driveway with daylight... she's getting opened up ! :wink:

 

[GGoodrum]

Would a picture of the insides show what you need to know ? :lol: I"m willing to open it up, no worries there.. :wink:

Probably, but you could also use the resistance mode on a multimeter, and just measure the negative outputs. Just put one lead on one, and the 2nd lead on one of the other ones. If they are not isolated, the resistance will go to zero. Also, check one of the negative outputs against the negative 12V input.

Thanks -- Gary

 

[Ypedal]

How's this ?

 

[liveforphysics]

And the bad..

out of 16 packs.. got one like this :

When you see double zeros like that, it often means you got lucky and it's just a balance tap wire that got tugged off, or they wicked it when they soldered it so it snapped inside the insulation when flexed etc. Generally when a cell dies, it ends up at like 0.03v or something slightly above zero, so it's likely all you need to do is re-attach a balance tap lead. But of course, you might just have happened to internally have some plate/plate resistance that let it drain clear to 0.00v...

But be sure to probe around and check before counting it out.


Ohh!!! Don't forget to report them to the shipping companies, then reverse the Visa charges, say they scammed you everywhere possible, etc etc, rather than paying $15 to mail the bad pack back and get a new one. It's always the most sensible choice, just ask Mdd0127.

 

[Hyena]

Ohh!!! Don't forget to report them to the shipping companies, then reverse the Visa charges, say they scammed you everywhere possible, etc etc, rather than paying $15 to mail the bad pack back and get a new one. It's always the most sensible choice, just ask Mdd0127.

Shit stirrer :lol:

You can also check if it's just a bad balance tap connection by measuring the whole pack voltage - if it's not reading ~4v low you know it's OK.

 

[johnrobholmes]

Thats enough muckracking, LFP. I want to hear more about this charger instead.

I'm guessing that reading on your meter means no continuity?

 

[GGoodrum]

That's good, it means the outputs are all isolated.

I agree with Luke, re: a broken tap wire connection. I've never seen a cell die like that, with the voltage 0.0V. Hyena's test is perfect. If you truly do have a dead cell the pack will be down about 4V, or so.

Luke needs a spanking, but I kinda think he'll like it too much...

--Gary

 

[MrKang]

Ypedal! i noticed your Lipo 4 pieces holder on the photo.

That looks awesome dude! can you take a better picture of that nice creation of yours?

 

[Ypedal]

Ypedal! i noticed your Lipo 4 pieces holder on the photo.

That looks awesome dude! can you take a better picture of that nice creation of yours?

The Black Box :
http://endless-sphere.com/forums/viewtopic.php?f=6&t=18296&start=30

:wink:

 

[El_Steak]

Nice...

Do you know if the Turnigy 4 port allows for adjustments to the LiPo end voltage? The Accucel 6 only allows you to go with LiPo (4.20) or Li-Ion (4.10)

I'm also quite sure the 0.00 cell is juste the balance wire thats broken, they are quite fragile. You don't need to open up the whole pack, you can access all the connections from the top of the pack, just remove a bit of shrink wrap and the little white plastic sheet.

I once dropped one of my pack from the table and grabbed it be the balance tap while falling. I broke off one wire.

 

[GCinDC]

Good idea to epoxy or ca gel the wires to the jst-xh connector too...

 

[Ypedal]

Good idea to epoxy or ca gel the wires to the jst-xh connector too...

Yeah, that is one thing ive been considering, i had the hot glue gun in hand a few days ago but without my charger and ballancers i had no way to know how far i could take it before they would not click in, or possibly get deformed by the heat of the hot glue.. Epoxy however..

I just plugged in a celllog8, coooooooool !!!!!.. i like the graph mode, 3 of these would give me my 24 cell SOC.. very good..

 

[Ypedal]

Opened up the bad pack , all connections are solid so it's not a ballance lead problem..

 

[Ypedal]

The 6 cells are covered in adhesive plastic , then covered with shrink..

If i can find a safe way to unsolder the tabs i'd like to make a 4S and a single cell by removing the bad one.. face shield, gloves and cinder blocks in the back yard ... project for next week's vacation time !

 

[Hyena]

Which cell is dead ? I've tried to salvage a few packs and murphys law dictates that it's always a cell in the middle that goes, making you have to seperate the glue from the cells on either side!

As Luke's videos have shown this things aren't as likely to blow up as everyone seems to thing. Mind you I was nervous doing mine, fearing I'd puncture the foil pouch trying to seperate the glue. Again from Lukes videos you can see they're not volatile as we've been lead to believe, and Aussie Jester and others have even sliced open the foil to release the gas build up causing puffing then glued them shut and kept using them without incident.

You'll need a beefy soldering iron to get them out. Also check out this thread if you haven't already seen it.
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=17494&p=257128&hilit

 

[GCinDC]

If i can find a safe way to unsolder the tabs...

Another thought would be just to clip the pcb to remove the cell. Not sure how doable that is w/ lipo pack, but it was much easier and cleaner than soldering my ping pack on the replacement job (thankfully on end cells!):

PS. Thanks for that view of the PCB! Nice photo. I'd always wondered...
Also psyched to hear about the stranded tape. Does it come in black...? :lol:

 

[Ypedal]

Got my 1st case of KFC tonight ~!~!~!~ ( Fried Connectors )

Found another pack with a cell going under 3v tonight, part of my last shipment, 5 cells at 3.8x volts and one at 2.98v .. .... so i put it on the charger for a minute to bring the low cell up above 3v and had to step away for a moment.. did not want to let the charger go while i'm not there so i stopped the charge cycle.

Came back a few hours later and wanted to swap my banana leads from the Icharger to the Turnigy 4x6 charger... pull the banana's out and got a sudder FLASH.... like Whoa Man !!!!..

I've had enough experiences with sudden sparks to not instinctively just throw stuff.. i seperate conductive pieces as a reflex nowadays lol..

Stupid me forgot the pack was still hooked up at the other end..

BIG difference between shorting 2C lithium " sparky spark " and 20C lithium !!! " BZZZZrrrrtt.. "

 

[Hyena]

You got off light, I did that once with with a multimeter probe and it completely vaporised it down to the plastic!

As a side note, the quality of your 4 pack turnigy charger looks quite nice from what's visable of it there

 

[AussieJester]

Have you tried getting the Turnigy cells apart yet YPedal Man? Its near impossible the glue they use between the individual
cells is piled on (was on mine anywayz) I was only able to prior the first cells off the pack i couldnt seperate the middle ones just wrecked them trying. Least i'm not the only one that has come across dead cell, just the only one thats lost near 12 packs because of it.

KiM

 

[Ypedal]

I think mkeefer has the right idea with the thin spatula, that's going to be my 1st method..

The solvent i'm not so sure about, might try zippo fluid, of all the stuff i've tried from rubbing alc to methanol to wd-40 to goo-gone etc etc etc.. nothing works better at disolving glue than liquid butane..

 

[Ypedal]

Re the Turnigy charger, i removed a few screws tonight..

 

[Ypedal]

other side

 

[Ypedal]

I wonder what these pins do ? software ? temp sensor ?