eX-cell 3100mah Panasonic based protected 18650 cells. Highest capacity worldwide!

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RedForest UK
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eX-cell 3100mah Panasonic based protected 18650 cells. Highest capacity worldwide!

    These cells are based on the new high-capacity Panasonic 18650 3100mah cell.

 

Link to pictures of label design, base cell data-sheet and actual cell: http://img69.imageshack.us/slideshow/webplayer.php?id=excellwrapper.png

 

eX-cell logo

 

eX-cell 3100mah Actual Cell

 

Data-Sheet


Info:

 

        3100mAh Capacity Typical (Minimum 2950)

        Built in PCM to protect from overcharge, overdischarge, short circuit

        Made in Japan

        4.20v±0.05 charge voltage, protection circuit cut-off set at 4.28v

        2.50v safe cut off voltage, protection set at 2.5v.

        3.6v Nominal voltage

        Charging type: CC/CV

        Max charge current: 1C (3.1A)

        Recommended charge current .3C (1.03A)

        Max discharge current: 6.2A

        Button top (low profile, the same style as Redilast cells) to keep cell as short as possible

 

 

    The cells are made to a very high quality, with the protection circuit and cell being sourced from top Japanese companies: Cell = Panasonic, PCM = SEIKO.

 

 

    These are currently the highest capacity protected cells that money can buy and having sourced all parts carefully from the best manufacturers and suppliers I believe that they are also the best quality as well. There are other quality manufacturers out there who I respect and will not speak badly of, but these cells are up there with the very best!

 

 I also believe these to be some of the safest 18650 cells on the market. The chemistry can be safely discharged to 2.5v, I apologise for any confusion, but my supplier has recently informed me that they did in fact fit 2.5v cut-off PCMs to these cells. This may be why it did not kick in before in my testing but I still would imagine that the PCM protection can be bypassed at low current or with a light run direct drive, please do not run the cell at low for an unreasonably long time (we're talking hours in most cases, it takes ages to deplete the cell when current drops so low) at lower levels after higher modes can't be accessed, unless you are willing to risk overdischarging the cell.

Again, the max low discharge of this cell is recommended by Panasonic to be 2.5v, lower than other li-ion chemistries, but still a very important thing to keep track of before recharging.

 

    I understand these cells are hardly 'budget' being the best currently on the market, but they will ship from the UK to most countries worldwide, and for what they are, at a very competitive price.

 

    The first batch will be a limited run of only 20 cells, the price will be £9.99 per cell or £27.99 for 3 cells and in multiples of 3 after that.

 

    Postage will be £2 in the UK for any number of cells. Price to the EU will be £3 for any number of cells.

 

Of course all Import and Customs duties have already been taken care of by me.

 

    US Prices are $16.99 per cell or $45.99 for three, postage will be $6 for any number of cells. Alternatively US customers can pay in GBP and postage will be £3.50 for any number of cells.

 

Worldwide shipping is also available: I can quote you a price if you message me, but it will be £3.50 to Australia and most other countries, just like the US.

 

 

Please Message me with interest, or post in this thread. If very interested, do both for a quicker response! Wink

 

If wanting to purchase, please post 'I'll take ___ (number of cells)!' In this thread and Message me, I'll send you my Paypal Address.

 

Thanks for looking Smile

Edited by: RedForest UK on 06/25/2011 - 11:29
sb56637
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Hmm, thanks for the offer! I'm glad to see this "Want to sell" forum being used.

I do like the cutoff voltage a lot. I own some fairly high quality XTAR 18700 Sanyo-inside cells, but I can't get the protection circuit to trip for low voltage, which really makes me wonder if it would work for high temperature explosion protection as well. I don't usually run my cells very hot, but my usage habits usually mean that I run the cell slowly to the ground, which isn't good for them.

Budget Light Forum ...where Frugal meets with Flashlight!

FlashPilot
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I will be impressed once these are independently tested and confirmed by our flashaholic battery gurus and withstood the test of time and punishment. Dont these have to be charged to 4.35V to attain 3100mAh? Cell is made in Japan but assembled in China (also assuming a made in China PCB along with the usual advertising claims that we are all used to reading about) At several times the price we pay for quality Japanese 18650 cells on this forum, I do believe I will definitely pass on this gracious offer. It is nice to see the availability of these exotic batteries for the masses and Im sure some enthusiast has probably had his eyes on these for a long time. Thanks for posting!

RedForest UK
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Hi FlashPilot, thanks for posting but I don't think you read through all my post. These do not need to be charged to 4.35v, they are 4.2v max as stated in the specifications. It is the completely different Samsung 3000mah cell which needs to be charged that high.

 

Also, as stated in the first post. The PCM (PCB is 'Printed Circuit Board' for an LED, PCM is 'Protection Circuit Module') is made in Japan, by SEIKO. Not in China as you guessed, according to what I assume was no information. The cells are assembled in China but that doesn't have to be a bad thing, this is done to a very high QC standard by the same people that assemble 'Redilast' cells.

 

Anyway, you are free to buy what you like, but I hope you will stick around to see the tests of these cells as I believe the results will be very good ones.

FlashPilot
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Hello Red Forest,

Thanks for the corrections! My apologies for not reading your add more carefully. The seiko PCM sounds intriguing as it might actually work! The trick will be for them to work consistently and accurately under varying load conditions.

I understand that these are new, but can you by chance provide an independent link where a respected private enthusiast has tested these batteries and posted results? I searched and didnt come up with anything.

If you would be willing to donate a cell or two to this forum, we have several respected battery enthusiast that would be more than willing to provide accurate faithful test results and post them here for comparisons on our battery database. The gurus will surely drop in as they read your post, but might I nominate "old4570" for his immense amount of battery testing that he has already conducted for us. If you are unable to donate, I understand... these are not inexpensive.

My fingers are crossed for this product being able to perform as advertised. That would actually be a new breakthrough for consumer level 18650's.

 

RedForest UK
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Don't worry about it. I didn't want to get frustrated but with you seeming to try and take a chunk out of these new cells before they've even 'lifted off' I felt a little defensive, as they really are top quality.

 

I am currently doing discharge tests to test the PCM right now to see where it cuts out. There is much information in another thread on BLF about the same base cells with capacity information etc. I will try and upload a picture version of the Panasonic data-sheet for these to include in the thread.

 

I would like to have these cells independently tested/reviewed, but was hoping some people may provide their testing data out of their own interest. I would send one to old4570 as his testing is good, but shipping to Australia is a bit much for just one cell (money is quite tight after just this first batch, I'm not a businessman, but a student) and the wait would be quite long. If someone here is willing to do a decent review with capacity testing/discharge curves, and who wishes to purchase some cells, I will offer a 20% discount for up to 5 cells for them. I would appreciate it if the same testing post could be posted on CPF as well though to reach a larger audience, and one probably more likely to be interested in these cells.

Don
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I'm in for 3 as per PM - Paypal sent in a minute. I was going to ask about the voltage too because I'd only heard of over 3000mAh cells that needed to be charged to 4.35V. This is much better. I may just have to build something that pulls around 6A for proper testing. 

 

Or something. With 6A to play with, a LOT of light ought to be available.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

RedForest UK
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Ok, great! I'll be very interested to see how well the PCM handles 6A continuous discharge, it is specified as 4-6A continuous, with 8-12A excess current threshold.

 

I've added a picture of the Panasonic data-sheet to the first post by the way.

 

EDIT: Please bear with me on the PCM cut-off tests, I've run it for the last hour at 0.5 dropping to 0.3A on the med mode of the manafont drop-in and it's only dropped from 3.49v to 3.28v, so it could be a while before it hits 2.8v..

..3.09v and 0.23A now almost half an hour later. The problem with the manafont drop-in is that it's completely unregulated, just using PWM percentages to create a dimming effect, so it will just dwindle and dwindle. I'll try and keep it going until it cuts out though.

I would use one of my DIY drop-ins but they all use NANJG drivers which have their own built in overdischarge protection (at 3v I think) so that wouldn't work. I'll try it in my T100C2 if this doesn't work out, that has a low 0.15A mode.

RedForest UK
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Unfortunately, the manafont drop-in drops out of any sort of regulation as the cell gets to 2.8v, pulling less than 0.05A on med and 0.01A on low, and by the time it has reached 2.6v, current is down to 0.03 on high, 0.01 on med and unregisterable on my DMM on low, so I believe it has bypassed the circuit. There is no risk of failing to notice the output dimming in a direct drive light like this however, especially at such extremely low voltages, so it shouldn't be much of an issue with this cell for which 2.6v is still safe. I'm running down to almost 2.5v though to be sure, then I will try it in my T100C2 which has some regulation, I think under a regulated load it should cut-off more quickly.

mitro
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In testing dozen of cells with protection circuits, I've never seen a single one kick in at recommended cut-off voltage (typically 2.8v). I think I'm going to test a few cells to see how low you need to go.

old4570
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There may be issue with the protection circuit cutting in, as many 3-4.2v divers have inbuilt protection 

So what happens is the driver switches to protected mode @ 3v and you get something like moon mode or less .

If you want to trip the protection , you should consider a buck boost driver equipped light, so when the voltage drops the driver begins to boost and really begins to drain the battery .. This should trip the protection circuit without fail . 

But this will be under load , and the voltage will begin to bounce back almost straight away , once the load is removed . 

 Always remember , the easiest thing in the world to do , is to expel hot air from your lungs and through some vocal chords ..
The resulting sound may , or may not be worth listening too ….

 

RedForest UK
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Yes, that is what I was thinking. But I would like to test if these cells do eventually cut-off at a safe point, otherwise I will have to remove my claim about running them until the PCM cuts in, which would be a shame.

 

The current has seriously dropped off in my T100C2 as well, it is at 0.06a now at 2.9v, I think I will go down to just below 2.5v this time to be sure. I really hate doing this to these cells though, I set aside two to keep for myself and now I am running one to within an inch of it's life.. It should be able to take it though, Panasonic say it can anyway.

 

Ok, I've had to call off the second test now as well, the light did go into a 'moon mode' type setting, and I gave up with the cell at 2.84v. I will try again as soon as possible but have to go test my new bike light out now before it's too late. I am going away tomorrow until Thursday afternoon so please don't worry if you can't get in contact with me until then.

Don
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I've yet to find a protection circuit that actually cut off on low voltage at low current drains. All of the ones I've seen thus far depended on boost drivers that would jack up the current to silly levels as the voltage dropped. If there is one out there that actually cuts off on voltage rather than current (for a price measured in pennies, not pounds), I'd get 100 of them tomorrow.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

RedForest UK
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I have now edited the OP to reflect the possibility of bypassing the PCM at low currents, please bear this in mind when purchasing any protected li-ion cells. That said, with this being an almost universal behaviour of li-ion cell PCM circuits these cells which can be discharged to a lower 2.5v than traditional li-ion cells should offer safer performance still. As by the time they are discharged that low, and in fact even significantly before that, current will have dropped to very low levels and it will be obvious the cell needs recharging soon.

 

In any circuit where current won't drop obviously at such low voltages, the PCM should trip successfully, doing it's job of protecting the cell.

FlashPilot
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Im looking forward to your review Don. Thanks for taking them on for the team.

As far as I am aware (and after reading all the comprehensive battery reviews at the other place) there isnt a PCM fitted to any 18650 that will reliably disconnect power once a target voltage is reached unless combined with a substantial current draw on the battery to trip the circuit. Only one of my cheap 18650 lights (that I am aware of) is equipped with a constant current regulator (light does not dim as the cells become depleted. Amperage draw increases as voltage decreases). My early example TR-1200 with 3 x 18650's will trip the PCM once voltage drops to around 3.6V while under a heavy load. The rest of my cheap lights simply dim, and if left on, will kill a battery all the way down to 0.0V. On my examples I have noted that the heavier a CC draw is on the battery, the higher the cutoff voltage becomes.

Lets hope for cool running, mega low resistance, higher capacity numbers @ 3A than the other offerings.

thommy
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I'll take 3 cells.

Shipping to Belgium please.

£27.99 for 3 cells + £3 postage = £ 30.99

 

mitro
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FlashPilot wrote:
Only one of my cheap 18650 lights (that I am aware of) is equipped with a constant current regulator (light does not dim as the cells become depleted. Amperage draw increases as voltage decreases).
I don't mean to nitpick, but that's constant power, not constant current. Smile Constant current would be just that... one current the entire time (like the battery discharge graphs above)
FlashPilot
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Right you are! Laughing

RedForest UK
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Only 9 left now until the next order, I'm off to the post office today to ship the first 3 sales. I'll not be back until tomorrow afternoon, (I am doing more than just going to the post office) so please don't worry if I don't reply to PMs right away.

Don
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Arrived this morning. That's the nice thing about stuff posted in the same country - it (usually) arrives very quickly.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

bushytails
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You could get six protected trustfire flame 2400mah cells (with free shipping) for the price of one of these 3100mah cells and shipping....  Sorry, just not worth it, for me at least.  It's not budget-light compatible with those prices, either...

--Bushytails

old4570
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Like comparing Apples and oranges ...

I wont buy a Ferrari cos I can buy 10 Fords , and thats fair enough . But possibly un-necessary to point out ..  I think it called flaming !  

Wish you the best of luck RedForest , and good to see you @ BLF   .  

 Always remember , the easiest thing in the world to do , is to expel hot air from your lungs and through some vocal chords ..
The resulting sound may , or may not be worth listening too ….

 

RedForest UK
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Can you? £9.99 + £2 = £11.99. Trustfire flames are £6 for two at DX, so you could get 4 surely? Believe me I have gone down that route before, the Trustfires are great cells for the money, they do pretty decent in low draw applications and some can even hold up to 2.5A. But the consistency and reliability just isn't there. I have had about 10 of them, and while 7 work fine, 3 of them have over time developed problems, and either can't sustain high currents (high resistance) or flicker on lower levels, or don't hold a voltage.

With li-ion cells I like to know exactly what I'm getting and be able to trust my cells to perform well and consistently for a long time. So I started moving further over to buying AW and Redliast cells, then I realised I could bring a higher capacity and equally high quality product to the market for less money. I know I will get comments about the price having listed on a forum dedicated to 'budget' options, they sure aren't 'budget' cells. But for their quality, they are actually priced noticably less than the competition.

trooplewis
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Seems to be a few  " based on the Panasonic 3100 cell" Li-on batteries popping up on the forums. I wonder what is happening that they are suddenly being marketed like they are the Ferraris of the battery world?

I see that the actual Panasonic 3100 is advertised for $6.55 per cell, why are the copies more expensive?

http://www.evvatech.com/sdp/1015379/4/pd-4967686/8681660.html

Rats, finally sold my 2010 509hp Mustang...now I can buy more lights!

Sold the red one too! Now guess what I drive, doing my penance for 500 hp commuters...

http://dreammustang.com/

http://i884.photobucket.com/albums/ac47/Ha

bushytails
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I went by US$, being as that's where I am - six at $8.38/pair is $25.14 with free shipping, while one of these is $22.99 including shipping...  so I exaggerated slightly - you can only get five and a half protected trustfire flames for the same price, not six.  Smile  So far I've had no problems with the trustfires, and with that price difference, I can throw four of them out and still have more mAh/$.

I've had problems with other brands, although I could get 14 of the ebay ultrafire 3000mah counterfeits for the same price as one of these....

And spending three times as much on a battery as the light I'd be putting in it seems just plain wrong.  Even after the xm-l and new driver I plan on putting in several of my lights, these cells still cost slightly more than the lights and upgrade parts...

Find a way to sell them for under $10/cell including shipping (that's still over twice what the trustfires cost), and I'll consider testing one or two.  Smile

--Bushytails

agenthex
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While ~$20 does seem a bit high, it's not exactly outrageous. The price above for loose unprotected cells is for minimum 100 and the going rate for standard sanyo's on ebay is $10/apiece. Just because kinda crappy cells are $5 apiece doesn't mean someone who wants to try the latest and greatest is overspending when it's only $20 anyway.

Reading this makes you smarter: http://lesswrong.com/

RedForest UK
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First I'd like to point out that these aren't 'copies' they are protected cells, using the 3100mah panasonic as a 'base cell' based on does not mean a copy but that the actual foundation of the cell is the 3100mah cell. Like the $17.75 AW and Redilast 2900 cells are 'based on' the panasonic 2900 cell.

 

I see what you mean with mah per $, but remember all those mah aren't in one cell, and you're paying for reliability etc. I very much understand the price argument from a budget light perspective though. I mean if I only had a light worth $15 then I would not pay more for a cell for it, unless perhaps I was considering that the cell would last through a good few years of use as my light was upgraded over and over..

 

Unfortunately, if I sold them for under $10 a cell including shipping then I would actually be making a significant loss on each and every one. Remember I have to buy in bulk, and I also have to pay not for a bare cell but for a cell with a protection circuit made by seiko built in with good QC process and gold plated contact on the rear + extra wrapping and a button top and the sticker. I also have to pay postage myself, the price quoted on the websites you like to read isn't like at manafont and dx where they make their money for the shipping on the item cost. I have to pay significant real world shipping charges on top of that too. EDIT: I also forgot to mention import taxes of 17.5% when it comes into the UK.

 

Actually, when you factor in my time organising/designing this and shipping them out, after selling these 20 cells I would have been better off taking on extra overtime working in my local supermarket on minimum wage. I am just hoping when they get noticed over on CPF you will get a number of people coming over to this site just to buy these cells, and I will have a steady stream of sales, if that happens it will be worth my while to continue selling. If not, then the opportunity to buy these cells at this low price will be gone.

 

By the way, Don, I'm glad you got the cells so fast! How do you like them?

old4570
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You only need to buy 100 to get that price = $6.55  that's $655 + shipping , unless you can pick up . 

If you got 1000 Im sure you could get an even better price .  

Then you could sell them in individual lots , so $655 + Shipping [ protection circuit ? + wrapped in your own label = hmmm wonder what that costs ] and then lets not forget something for your trouble , and the final price = ?  

Sorry guys , you dont get something for nothing :  and the few Jap cells I have , are better than the Chinese ones .

Im not forcing anything on anyone , but seriously , it takes a fair bit of Gumption to go out and make something happen , and I really dont see why the need to  flame  , if your not interested thats fine , but why this ?  

This is no different than getting flamed over at the other site for mentioning budget lights !  

 Always remember , the easiest thing in the world to do , is to expel hot air from your lungs and through some vocal chords ..
The resulting sound may , or may not be worth listening too ….

 

edc
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I am surprised at the "flaming" that occurs in for sale threads at CPF. I am a member of other forums (not flashlight/knives) where comments in for sale threads that are not related to buying the item are not tolerated. I would not like to see that kind of heavy moderation here but as old4570 says if your not interested , don't comment. 

 

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mitro
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I think the issue here is that this may not be the best place for selling cells like this. BLF is generally about "bang for the buck". While these likely provide the most "bang" (in a good way) they also cost quite a few bucks.

I think maybe those who like the idea of $7 3100mAh cells ought to do a group buy and then figure out just how much it ends up costing to get them assembled with protection circuits and shipped all over the place. Either that or just use the bare cells at $7. That extra stuff (and labor and logistics) isn't free.

trooplewis
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I don't want to come across as flaming anyone, but when they advertise the cells as the highest capacity, highest quality, currently on the market, I think that deserves some explanation. Especially when there is another thread running concurrently about batteries based on the same Panasonic 3100, making about the same claims. Just seems like there are new ones suddenly popping up that I've never heard of.

Nice that technology is advancing, or that Panasonic is licensing out its technology, I'd just kinda like to know what the story is.

 

thanks, Red Forest, for the explanation.

Rats, finally sold my 2010 509hp Mustang...now I can buy more lights!

Sold the red one too! Now guess what I drive, doing my penance for 500 hp commuters...

http://dreammustang.com/

http://i884.photobucket.com/albums/ac47/Ha

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