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19859 Posts in 1275 Topics by 5187 Members - Latest Member: charbuild August 13, 2022, 10:42:44 AM
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Breaktru Forum  |  eCigarette Forum  |  Battery  |  Topic: Sony US18650VTC5
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Author Topic: Sony US18650VTC5  (Read 10437 times)

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Offline CraigHB

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Sony US18650VTC5
« on: March 14, 2014, 04:47:09 PM »
Just saw the Sony US18650VTC5 is in stock at retailers.  These guys have them;

http://www.orbtronic.com/sony-18650-2600mah-vtc5-30a-high-drain-hybrid-imr-li-ion-battery

Sony got those out fast, the VTC4 wasn't out that long.  These 18650s just keep getting more amazing.  30A drain and 2600mAh, what more could you ask for.  I thought that LG battery was really amazing and Sony topped it.  Would love to see the official data sheet.

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Re: Sony US18650VTC5
« Reply #1 on: March 14, 2014, 05:31:19 PM »
Great news Craig. Ordered 2 of them

Offline Jackson

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Re: Sony US18650VTC5
« Reply #2 on: April 10, 2014, 07:15:37 PM »
FWIW, Sony has the lamest datasheets I've ever seen, and this one no exception.  And I have no idea where these 30A ratings come from.

http://www.intaste.de/community/dtf/technical_information.pdf

I don't know which LG you are referring to, but this one which is often labeled as 35A appears to actually be a 20A cell per LG's Continuous Max Discharge rating.

https://drive.google.com/file/d/0By-7aw3qPc-oa09ENnNFMUtxTFU/preview?pli=1


Offline CraigHB

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Re: Sony US18650VTC5
« Reply #3 on: April 10, 2014, 08:22:16 PM »
The only indication in that data sheet is a discharge curve up to 20A.  It doesn't state the actual maximum discharge rate so yeah, that data is missing.  Though, you can see with the 13 mOhms internal impedance it's definitely good for 20A continuous allowing a 30A burst rate.  Still that's really good for a round cell.  The 1400mAh 10C LiPos I have are about 25 mOhms and the 20C 2200mAh LiPos I have are about 6 mOhms.

Yes, the high drain 2500 mAh LG cell is rated for 20A continuous.  It also has an internal impedance of 13 mOhms.

Whatever the case, these cells are extremely efficient with their very low internal impedance.  They're good for any load you could put on them practically with an e-cig mod.  If that's not good enough, you can always parallel a couple of them for a 40A continuous output.

I've also seen 30A and even 35A rates claimed in listings for these cells.  I have no idea where vendors are getting the data to claim those rates unless they're using burst rates which are not stated in the data sheet.  Typically burst rates are the continuous rate + 50%.  In that case they're 30A cells, but in terms of continuous rates they're both 20A cells.

Offline Jackson

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Re: Sony US18650VTC5
« Reply #4 on: April 16, 2014, 06:55:15 AM »
Well you seem to have a lot of faith in data provided by the manufacturer who obviously will use a prime, cherry picked battery.  Will we as consumers get the same battery?

I saw this somewhere.



Am I correct in assuming that the paralleled reading will actually double for a single battery = 18m? or 35% higher than the spec you listed?

Offline CraigHB

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Re: Sony US18650VTC5
« Reply #5 on: April 16, 2014, 03:42:24 PM »
Keep in mind, that meter is also measuring the resistance of the wires and the resistance of the contacts to the battery.  It's not unusual for contact and wire resistance to be equal or greater than that of the battery.  To get a true reading, you need to to calibrate with respect to contact and wire resistance.  That may be the case for the measurement in that photo, but there's no way to tell just by looking.

I would probably trust the specs listed in a data sheet before that of a hobby meter with a regular battery holder.  Even so, it's not that far off.  The reading indicates 18m Ohms per battery which is pretty close to the impedance spec stated in the data sheet.

Also, the specs in the data sheet are internal impedance measured with a 1 kHz frequency generator and analyser.  This is not the same as the voltage drop you would see using that number as a resistance value.  Resistance and impedance are not the same thing, though they can be under purely DC conditions. 

The internal impedance spec is reflective of a battery's DC performance and it's a good number to use for comparison purposes, but it's not necessarily going to provide the actual voltage drop seen when the rubber hits the road.  In some data sheets you see the DC resistance value as well as the impedance value.  DC resistance is usually a bit higher.  That makes the number seen in the photo quite reasonable if that meter is measuring DC resistance and not impedance as stated in the data sheet.

As far as "cherry picking", there may be some of that going on.  They usually spec the prototypes and then put limitations on how much units can vary from that coming off the line.  There's always a number of cells coming off the line that end up in the recycle bin so you can end up with one either better or worse than the stated specs.  A quality maker puts a pretty tight tolerance on that kind of thing.  This is the primary difference between a Japanese and Chinese cell, the consistency in quality.

In my own experience with quality cells, I've not found the impedance spec to vary much from one cell to the next.  I've have yet to end up with one that has a markedly higher internal resistance than another.  It's something I pay pretty close attention to in testing.


« Last Edit: April 16, 2014, 04:03:09 PM by CraigHB »

Offline richard31

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Re: Sony US18650VTC5
« Reply #6 on: May 22, 2014, 07:36:17 AM »
I was in search of this kind of Battery

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