Sony US26650VT source!

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pwbset

100 kW
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Well... I really didn't want to share because I was hoping to snag all these myself :wink:, but I've already got 100s of good 18650Vs so I'm going to spend my money building a stupid tab welder instead. Anyway... it seems that the Ingersoll Rand IQv lithium toolpacks have the Sony US26650VT cells in them. I've emailed them to confirm 7s in their "19.2v" pack as the charger max voltage is 29.4v, which is consistent with 4.2v/cell @ 7s. These cells have 50A max current and 2.5ah... ES member drewjet built a pack with them awhile ago so maybe he'll chime in... anyway... here's an ebay listing for some right now:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190312020223

The seller is very responsive and said he has 1,300 of them and doesn't need them all... he added his Ingersoll Rand toolpack source and a closeup of the cell text for me within a day. Even with unknown cycle life $2.75/cell seems reasonable and I bet he could be talked down with a bulk buy.

Anyway... happy shopping!! Wish I wasn't married to my stupid little 18650s! :lol: *sigh*
 
Interesting. I wasn't aware that Sony made these in the larger format, like the a123s. I sent the seller an inquiry for what about 100 would cost.

-- Gary
 
Excellent! :wink:

Now we can convert 36V dewalt pack to 42V !! :lol:

Just one thing.. they suggest a voltage range of 2.5 to 4.2

If you want these VT cell sto last at least 300 cycles with ebike use, than use 3.0 to 4.1V

The LiMn VT cells are not 4.2V.. they are 4.1V charge... they tolerate 4.2V but that affect theyr cycle life!.. same thing about the 2.5V... 3.0V is safer and make the cells to heat less! ..again less heat give better cycle life!! so the 0.5V you loose is very compensated by the lomger cycle life gained!

Also, this is unusefull to put electrical seperator between paralleled cells! :wink: just put them between each group in serie!

Doc
 
Great find and a dirt cheapm price. I am using 216 of these in a 18S12P setup. I charge to 4.2 volts as thats what my balancing charger does. I don't know how many cycles I have on them, but I do have 3200 miles. I probably average 8 miles per charge so in the neighborhood of 400 cycles. They are still going strong. I had one of the parallel strings go bad, but it was my fault in the build, as it shorted out. No smoke no fire just 12 dead cells. I rebuilt it with the few extra cells I picked up and it hasn't missed a beat. I think I will pick some up, so that I have spares again. Thanks for the tip.

Drew
 
Hi,

pwbset said:
Well... I really didn't want to share because I was hoping to snag all these myself :wink:, but I've already got 100s of good 18650Vs so I'm going to spend my money building a stupid tab welder instead.

Anyway... happy shopping!! Wish I wasn't married to my stupid little 18650s! :lol: *sigh*
Click to expand...
Maybe selling your 18650V's, getting some Dewalt end caps and buying the US26650VT won't cost much more (and be a lot easier) than building a tab welder and using the 18650V's.

pwbset said:
Anyway... it seems that the Ingersoll Rand IQv lithium toolpacks have the Sony US26650VT cells in them. I've emailed them to confirm 7s in their "19.2v" pack as the charger max voltage is 29.4v, which is consistent with 4.2v/cell @ 7s.
Click to expand...

Do you know which of their packs use the Sony US26650VT cells?

Is the nominal voltage 3.7v?
 
Thanks! I just clicked for 50 of these to try and make a 7s5p pack for my Kollmorgen unmodified motor with built in controller (24V).

With the extra 15 cells to be used as replacements or the possibility of going to 10s5p in the future.

I plan to machine a drop in holder for the 35 cells out of delrin on my cnc mill.

So what was the final verdict on charging these? I know the 4.1V per cell. I gathered that they were about as volatile as the A123 cells (and the same size, which makes them attractive)
 
Does anyone know if these cells require a BMS or do they stay well balanced like the Sony 18650?

Anyone know if these cells are still in their original pack form? ie tabs still on.

John
 
I use a balance charger every single time, they do appear to always be in balance, but I rarely check, since the charger does it automatically. I think having 12 of them in paralell helps also. Personally I would never use lithium (any lithium) with out some form of balance charging or BMS, but that's only my opinion.

So far, for me, charging to 4.2 has not been a problem.

I ordered 24 of them my self.
 
John in CR said:
Does anyone know if these cells require a BMS or do they stay well balanced like the Sony 18650?
Click to expand...

The Sony/konion cells don't stay balanced any better than any other higher quality cell, like an a123, or a PSI/BMI cell. The reason Doc's packs stay balanced is mainly because he never discharges them anywhere close to a LVC point. Another factor is that Doc has like 15 cells in parallel. This definitely helps average out differences in capacity, etc.

I've got packs made with 4 and 5 a123 cells in parallel, and they too stay very well balanced, until the first time the pack is drained down to LCV. At that point, the cell blocks will definitely get out-of-balance.

-- Gary
 
Gary,

I beg to differ. A company like Bosch isn't going to give a 1yr warranty (which can easily be extended to 3yrs for free if you register in time) if the pack wasn't proven durable. They have no BMS, so obviously one isn't required. The Makita packs that Doc gets as returns don't have BMS's either, and the majority of those returns resulted from a faulty tab weld from the factory.

As a test of one of my packs, 5 strings of 2p17s (18650V cells) with the 5 strings paralleled at only the ends, I over-discharged the pack and then over-charged the pack. At first the pack was out of balance to some extent, but after using the pack daily for a few weeks with very conservative charge and discharge, I finally got around to manually balancing the pack, but then it didn't need it. Somehow the pack returned to acceptable balance with all cells within a range +/-.04V, which was barely worse than my initial manual balancing of the pack after assembly. Try that with A123's and you'll kill perfectly good cells.

Keep in mind that I wasn't as scientific as Doc regarding cell matching. All I did was put the cells in strings of about 230V and discharge them using a pair of lightbulbs in series. I then matched them based on ending voltage as my caveman version of capacity matching.

John
 
Hi Gary,

Maybe Richard's post explains this?

http://endless-sphere.com/forums/viewtopic.php?f=14&t=7015&p=105868&hilit=+overcharge#p105868
fechter said:
Limn have a higher energy density than LiFePO4 but most have a slightly lower power density, so the maximum C rate for discharge may be less.

Most do not use a BMS other than a whole pack LVC. During charge, they can tolerate a fair amount of overcharge without damage, which allows balancing without cell level monitoring. I suspect they might last longer with cell level monitoring.
Click to expand...
 
I hadn't seen Richard's post about this, but his comment about tolerating a bit of an overcharge makes sense, as that would mean they can sel-balance, to a certain extent. That would explain how John's cells got back in balance over time. I''ve only played with single string cells/packs, mainly with RC helicopters, and draining them down too far will get them out-of-balance, for sure. I just never tried just charging them up as a series string multiple times, to see if they would self-balance.

This is definitely a big plus for these, over LiFePO4-based cells, but like Richard says, this might not be the best thing for longevity. I think what I'd do is still use cell level LVC, which should keep them from going out of balance too far, and then still try and charge them to at least 4.1V. The one thing I really like about a123s is that I can drain them to LVC cutoff, and charge them to 100% and they still keep plugging away. I haven't seen any real degradation for any of my healthy cells/packs. The whole capacity is fully usable. If the big konions can come close, without having the complexity of a full BMS, that would make them much more attractive to me.

-- G.
 
Well,

I went ahead and got me a bunch of these. Will be so happy to get away from the weight of the the SLA's.

I think I'll make up a BMS using the Goodrum / Fecter design, http://www.tppacks.com/products.asp?cat=26 - number of balanceing points yet to be determined. And at that point I''ll probably grovel for some input on how to get the proper cell-level voltage applied by changing the resistors. That will require some study here before I can ask the proper questions and properly interpret the answers.

I wonder : could there be a way to put a variable resistor or 2 in place of the fixed resistors for the voltage divder circuit to be able to vary the target cell voltage?

I have a Ping 2.5 48V - 15Ah unit on order, and this would have a somewhat different cell voltage target then these.

I wish I could buy several of M1 bat. pack const. kits just about now.
http://www.tppacks.com/products.asp?cat=13

Thanks for the amazing resources developed here.

Joe

If it seems like I don't know precisely what I'm talking about - you've reached the correct conclusion.
 
Joe,

I definitely wouldn't go further than doing some capacity matching of the cells before assembly, and using a balancing charger (rc lipo chargers come to mind). To me introducing anything unnecessary just gives you more points of failure. The LVC of your controller offers plenty of protection, and even that isn't really required if you pay attention to your bike's performance, because these cells sag quite noticeably in that last 25% of capacity. ie your bike starts slowing significantly and you need to already be well on your way home.

Spend the money you save on more cells, so you can run more conservatively. Then a pack of these will serve you well for 2-3 years if you treat them nicely, and by then better cells should be even cheaper.

John
 
First off, thanks for the lead!

I'm in a similar situation as Joe... I read in another thread that in a case like this, it's best to buy first and ask questions later. :? So I've ordered 100 of them, now I need to figure out how to best use them.

I would like to run a pack around 60v, so I was planning on running 16s6p, which should give me around nominal 58v 14ah. What I would like to do is build them as two 8s6p packs with the ability to parallel them and plug the balancing leads together resulting in a 8s12p pack for charging purposes. I could then do all the charging/balancing with an icharger 208b.

I still need to look into some of the details such as how to capacity match them, etc. I know the 208b has discharge capabilities, so perhaps it has some built in tools to do that testing? I need to research it further. But I first wanted to make sure my general intent is sound before buying the charger.

Thanks!
 
I run 17s with my 18650 Konions, which seems to be a perfect match for my 60V controllers. My first advice is DO NOT BREAK THE CELLS APART if they come in their original factor tabs. It's much easier and less risky for the cells to solder on existing tabs rather than directly to the cells. I've processed way over 1000 used Konion cells, and you can count on lazy me to find the easiest way to do things.

I started with used cells, so if the cells in the toolpack where in balance, I could assume those were already well matched, so I tried to do as much as possible on a sub-pack basis instead of cell basis, reducing my work by a factor of 6 or 8. I charged all the packs in parallel to give me an at rest cell voltage of 4.15V (full enough for me). I put mine in long series strings, and discharged about 2/3rd of nominal capacity at less than .5C with a series of regular lightbulbs for 2 hours. For 100 cells I'd do them all in one shot, and run the discharge more than once, since the cells aren't used (bad pvb on the toolpack), charging to the same voltage and running for the same time using the same lightbulb string.

I then used the ending voltage after discharge to match the packs together and form my series strings. Equal starting voltage + equal discharge + equal ending voltage = equal capacity for maintaining balance over the long haul. At least that's the way I did it. DoctorBass does a sophisticated capacity and impedance matching system for his cells, which on paper is the optimum, and his packs maintain perfect balance. At the other end of the spectrum, YPedal just applied a bit higher initial charge to the packs and tossed any that wouldn't hold a 4.15v charge, but then ran his pack very conservatively for a year with pretty good results, though I think my method can be quicker with not much more effort with better capacity matching.

John
 
Hi,

joe tomten said:
I think I'll make up a BMS using the Goodrum / Fecter design, http://www.tppacks.com/products.asp?cat=26 - number of balancing points yet to be determined. And at that point I''ll probably grovel for some input on how to get the proper cell-level voltage applied by changing the resistors. That will require some study here before I can ask the proper questions and properly interpret the answers.
Click to expand...
That BMS is pretty complex to setup (particularly for cells that are supposed to self-balanc). I'd use a Chargery BM6 for Cell Level LVC:
https://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8927

Its discussed here:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=9229&p=159610
http://endless-sphere.com/forums/viewtopic.php?f=14&t=9229&p=159610#p159610
I see the BM-6 on hobbycity. look here, it's only $13
Click to expand...

For charging you could use an RC balancing charger or single cell chargers. Single cell chargers are discussed on the following threads (IMO either will be simpler than the BMS):
http://endless-sphere.com/forums/viewtopic.php?f=14&t=9522#p147464
discussed in depth here:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=2586
http://endless-sphere.com/forums/viewtopic.php?f=14&t=4057

joe tomten said:
I wish I could buy several of M1 bat. pack const. kits just about now.
http://www.tppacks.com/products.asp?cat=13
Click to expand...
If you can find some Dewalt end caps Gary thinks this is easier (follow the discussion to the end of the thread:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=2498&start=360#p133042

dscline said:
I would like to run a pack around 60v, so I was planning on running 16s6p, which should give me around nominal 58v 14ah. What I would like to do is build them as two 8s6p packs with the ability to parallel them and plug the balancing leads together resulting in a 8s12p pack for charging purposes. I could then do all the charging/balancing with an icharger 208b.

I still need to look into some of the details such as how to capacity match them, etc. I know the 208b has discharge capabilities, so perhaps it has some built in tools to do that testing? I need to research it further. But I first wanted to make sure my general intent is sound before buying the charger.
Click to expand...
The iCharger will measure the cell capacity in mah. Cellpro 10s will also measure Cell Capacity. I'd consider using either 2 iChargers or 2 Cellpro 10s chargers and charging the entire pack at once.
 
I just got my 24 in the mail (enought to replace 2 strings if ever needed) They look in good shape, I haven't checked volts yet. They did have tabs welded (The first ones I bought did not), but the tabs have been removed.
 
drewjet said:
They did have tabs welded (The first ones I bought did not), but the tabs have been removed.
Click to expand...

Yeah he said he got these from Ingersoll Rand IQv battery for toolpacks, which obviously should alert all the people scrounging for toolpack rejects to now be on the alert for Ingersoll Rand stuff as these are very good cells and I'm sure everyone could use more access to them. 50A burst is impressive from a single 26650!
 
FWIW, I work for Ingersoll Rand, and after seeing this thread I looked in to buying some battery packs for myself with my employee discount. But that's still a LOT more than buying these off ebay. :?
 
Hi,

dscline said:
FWIW, I work for Ingersoll Rand
Click to expand...

Do all Ingersoll Rand packs with Lithium cells use the 26650 Konion Cells?
 
MitchJi said:
Do all Ingersoll Rand packs with Lithium cells use the 26650 Konion Cells?
Click to expand...
Honestly, I have no clue. I work for Trane (air conditioning). We were bought last year by IR, so we are one company now, , I'm an IR employee, and I can buy IR products with a discount (actually, a rebate after you buy it at a retail outlet), but I have no knowledge of IR rand products, or any of the other brands that are part of IR. I didn't even know they (we?) had a cordless tool line until I saw this thread. :oops:
 
I checked volts, all are 3.7 plus or minus .05

I am happy, wish I had more $
 
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