Twelve NEW 2400mAh 18650s, under $30?

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comfychair
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Twelve NEW 2400mAh 18650s, under $30?

The HP DV4 (and similar models, not sure what all interchanges) have an optional extended 12-cell battery. The originals were rated as 8800mAh, which works out to 12 2200mAh cells inside - I bought a lightly used pack and opened it, found 12 LG 2200Ah 18650s, all in good condition. But used packs are always a crapshoot, especially if you know nothing about how it was treated in its former life.

So completely by accident I stumbled across *new* aftermarket DV4 packs on ebay, with an upgraded capacity (advertised, unconfirmed) of 9600mAh, which meant that if true, there should be 2400mAh cells inside. And the price with free shipping is, somehow, under $30. What?!

http://www.ebay.com/itm/310405754542

I bought two, and cracked them open. They may be complete garbage when used as intended as a laptop battery, but who cares about that, right? Here's what you'll find inside...

One thing to note, there was a sticker on the PCB inside that said "DV4 8.8AH", which may mean nothing fishy going on with the 9600mAh advertised rating. The internal circuitry would be the same whether the cells used were 2200 or 2400mAh, and these could have been from the same batch used to build the 8800mAh packs. Without identifying these particular cells, I'll never know.

From what I can figure '6K00112' is the model (I have 6 CJ cells from a different pack, and they are marked 6E00312) and CJ is the manufacturer... but I have no info on who or what CJ is, other than some hits for similar cells on alibaba and the like.

All cells from pack #1 were at 3.84v after they were all separated; pack #2 cells were 3.80v. All 24 charged up just fine in a XTAR WP6.

And finally, a tip for my fellow cheapskates who like cracking open laptop packs. Get yourself some of these:

Outside snap ring pliers, most commonly used for things like retaining syncros/gears/bearings on transmission shafts (remnants from my previous incarnation as an auto tech... *shudder*). Once you break open a small spot between the two halves of the casing, stick the pliers in and squeeze. POP! POP POP! And the pack is opened. No Dremeling, no hacksaws, no poking holes in the cells trying to use a screwdriver. Couldn't be easier, and on top of that you're much less likely to damage the goodies inside. Win/win.

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bads3ctor
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Have you verified the capacity of these batteries? Are they really 2400mah? I’d like to give them a try but I don’t want to find out they are 1000mah used Chinese retreads. Thanks.

comfychair
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No, I don't have anything to test capacity other than using them in lights, and compared to known 2200mAh LGs they have significantly longer run times and push more current through the same load - direct drive into two XM-Ls in parallel on copper the LGs do 4.5 amps and these 'CJ's do 5.71 amps. Out of the 24 there were 4 that had the heatshrink damaged when the tabs were welded which I re-wrapped, nothing under the cover that would indicate they're anything other than brand new cells.

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comfychair
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Look at it this way: what other options are there for 18650s for less than $2.45 each? Red/silver Trustfire "3000mAh", at a little under $2 each? I got 4 of those with the first lights I bought, 3 of them would trip the protection at 3 amps and shut the light off. The other one would just flicker even after the protection board was removed, there's something not connected inside the case. On all 4, the button tops weren't welded, held on only by the heatshrink. They are complete total garbage.

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ohaya
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Hi,

I’d be interested in these, and I have an Accucell so I can do a discharge test. Based on what you all know thus far, is it worth a try? Seems like that’s the case from this thread so far, but let me know?

Thanks,
Jim

jakey
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Bummer +10 dollars shipping to uk,But if you guys test and they r ok still might b worth it

let there b rock (i mean light)

ohaya
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Hi,

Well, I’ve gone ahead and bought one. Ebay says delivery by 3/11, but I think that I’ve dealt with this seller before, and what I bought got here (VA) faster than that… Will post back.

Jim

ohaya
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Figured it out. Sold by “N&K Trading”… Looks like that is tmart.com, or someone/something associated with with tmart.com.

Jim

marcl
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jakey
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Look similar,$47 therabout for twelve so if you pay $40 for the lap pulls its not so good to us in the uk.Thanks marc.

let there b rock (i mean light)

ohaya
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jakey wrote:
Look similar,$47 therabout for twelve so if you pay $40 for the lap pulls its not so good to us in the uk.Thanks marc.

Plus you’d get 6 battery boxes too :)!!

Jim

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Google finds hits on what appears to be these cells. After some searching, I suspect these are 2200mAh cells… when they were new.

One of the links found a MSDS
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&sqi=2&ved...

No wonder Majicshine cells are so crappy. But for what you paid, and if youre happy with them, thats all that matters.

ohaya
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cat eyes,

What is “BAK”?

comfy chair,

Your pictures didn’t show it, but do these cells have button tops? Or are they flat tops?

Jim

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jakey wrote:
Bummer +10 dollars shipping to uk,But if you guys test and they r ok still might b worth it

Try this one: http://www.ebay.co.uk/itm/190776517081

A few interesting links:

http://www.dailymotion.

ohaya
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cat eyes wrote:
ohaya wrote:
Figured it out. Sold by “N&K Trading”… Looks like that is tmart.com, or someone/something associated with with tmart.com.

Jim

i have bought a lot of stuff from them on ebay….
i did not know they were tmart…..
so maybe we can buy from tmart and get it shipped from new york….
and they have a warehouse in UK also…..

Hi,

The Ebay listing says New Brunswick, NJ, which is probably like across the river from New York:

http://maps.google.com/maps?rlz=1C1CHFX_enUS519US519&q=new+brunswick,+nj...

Incidentally, I’ve bought a lot of stuff Newegg, and that always inevitably ships out of Edison, NJ, which is almost the same place…. coincidence?

Also, before I bought the pack off of Ebay, I did do a brief search of Tmart.com, but that pulled up like 25 pages of results. The one 9600 mAh one I found was $34.99, but it looked slightly different than the pic on Ebay:

http://www.tmart.com/Laptop-Battery-7200mAh-11.1V-for-Dell-Studio-1737-1...

Quote:
This replacement battery is compatible with Laptops for HP. With this battery for your notebook you can get long hours of battery life without having to frequently plug-in to recharge. Long enough battery life is essential to optimizing your productivity while in meetings or traveling. Get one, you will never regret! Features New high quality generic Li-ion Battery Original manufacturer compatible No memory effect. Chargeable even if it has not been used up yet Specifications Condition New Product Type Replacement Battery Cell Type Li-ion Cells 12 Whr 103.7 Voltage 10.8V Capacity 9600mAh Color Black Compatibel With HSTNN-Q34C, HSTNN-C51C, HSTNN-C52C, HSTNN-C53C, HSTNN-W48C, HSTNN-W49C, HSTNN-W50C, HSTNN-DB72, HSTNN-DB73, HSTNN-IB72, HSTNN-IB73, HSTNN-UB73, HSTNN-CB73, HSTNN-LB72Compaq Presario CQ40 series, Compaq Presario CQ45 series, Compaq Presario CQ50 series, Compaq Presario CQ60 series, Compaq Presario CQ70 series, HP DV4 series, HP DV4-1100 series, HP DV4-1200 series, HP Pavilion DV5, HP Pavilion DV5-1000 series, HP Pavilion DV5-1100 series, HP Pavilion DV5-1200 series, HP Pavilion DV5T, DV5Z series, Hp Pavilion DV6 series, HP Pavilion DV6 series, HP Pavilion G50 series, HP Pavilion G60 series, HP Pavilion G70 series, HP G71-343US, 485

Re. flat vs. button top: I looked more closely at the pics from the OP, and those do look like flat tops.

Jim

P.S. On my purchase from Tmart, the payment went to N&K Trading_tmart, thus my “guess” that the ebay seller is tmart.com, or associated with them.

ohaya
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cat eyes wrote:
well they sell chinese batteries so make sure you get them cheap… do you resell lights ???

cat eyes,

Who were you talking to/asking?

Jim

ohaya
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ohaya wrote:
cat eyes wrote:
well they sell chinese batteries so make sure you get them cheap… do you resell lights ???

cat eyes,

Who were you talking to/asking?

Jim

Hi,

Oh, ok….

No, I don’t resell lights :).

It’s just that I’ve just gotten interested in lights fairly recently, and there’s a TON of stuff to learn about (for me).

I have a technical background, but it’s been all work, while this is actually FUN, so it’s like “a kid in a candy shop”… and, BTW, I think I’ve mentioned on other threads, my wife is already starting to hate it, because of the pile of lights, batteries, chargers, and rigamarole that I’ve accumulated in the last 1.5 months.

Jim

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ohaya wrote:
Quote:
Compatibel

Haha, yep, same creative spelling in the ebay listing.

-----

Is there good evidence that any cells made in China are automatically 'retreads'? That's not a leading question, I'm truly asking. I know about some of the quality issues, like everybody else I got burned years ago by the Chinese capacitor scandal, but capacitors and batteries are different animals. Lots of circuits still work passably well even when some or all of the capacitors are completely ineffective... for a while, until they vent. Can they really use river water and ox dung in a LiIon cell and have it still work?

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comfychair
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I would dearly love to have a tackle box packed full of fifty Panasonic 3400's or Samsung INRs, but not so much I'd be willing to give up food to get them.

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comfychair
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These aren't HP packs, they're aftermarket replacements. The genuine HP-branded OEM packs use LG - at least based on the one sample I opened.

edit: The OEM 12-cell pack for the HP DV4 used LG cells... they may use something else for other and/or newer models.

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comfychair
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Nearest Home Depot is ~90 miles away... Sad

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nekdo12
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cat eyes wrote:
ohaya wrote:
cat eyes,

What is “BAK”?

comfy chair,

Your pictures didn’t show it, but do these cells have button tops? Or are they flat tops?

Jim

BAK is a chinese battery factory….
the post above mine references magicshine and they sell BAK batteries for their bike lights…
BAK makes these batteries we are critiquing

and coming out of a laptop pack i would guess that they are flat top

Fenix 18650 has also BAK cell.
http://lygte-info.dk/review/batteries2012/Fenix%2018650%20ARB-L2%202600mAh%20%28Black%29%20UK.html

ohaya
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cat eyes wrote:
oh…ok….
well good luck hope you get sanyos next time…..
the black and decker battery packs at home depot
had 10 sanyos for $22 last week…..

sku 342082
on sale in store not online

They’re $89 now:

http://www.homedepot.com/p/t/203081187?catalogId=10053&langId=-1&keyword...

but not available in any stores near me :)…

Jim

comfychair
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Crude but interesting results...

Solarforce S1100, 3x18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

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ohaya
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comfychair wrote:

Crude but interesting results…

Solarforce S1100, 3×18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

comfy,

I’m losing track of this thread. Are the “BAK/CJ” ones you mention above the ones from the $30 laptop battery (the one I just bought :)!)?

Jim

P.S. Are we sure that the BAK/CJ ones are actually manufactured by BAK?

comfychair
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ohaya wrote:
comfychair wrote:

Crude but interesting results...

Solarforce S1100, 3x18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

comfy, I'm losing track of this thread. Are the "CJ" ones you mention above the ones from the $30 laptop battery (the one I just bought :)!)? Jim

YES.

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comfychair
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ohaya
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Hi,

I wanted to keep you all up-to-date. The one I ordered is now in Secaucus, NJ, on its way to me in VA. That’s the same place the orders I had from Tmart.com came through before.

The unfortunate part is that in the 2-3 orders I got from Tmart in the past, the shipments seemed to sit in Secaucus for a couple of days. Hopefully, that won’t be the case since this was purchased through Ebay, but we shall see I guess :)…

Later,
Jim

comfychair
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I got mine in 6 days, including a weekend, from NJ to MS. USPS is weird like that sometimes.

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marcl
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comfychair wrote:

Crude but interesting results…

Solarforce S1100, 3×18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

Comfy, are these good readings? I’m not familiar with this light. Also are you saying these are good cells or not? The reason I ask is because I actually want one for my HP, so it’s probably a better deal for me than anyone.

I will have to get the one in Reduk’s link of course, but I presume they are the same.

Marc.

Eagles may soar, but weasels don't get sucked into jet engines!

ohaya
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comfychair wrote:

I got mine in 6 days, including a weekend, from NJ to MS. USPS is weird like that sometimes.

Still in Secaucus, NJ today (Tuesday)…

comfychair
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marcl wrote:
comfychair wrote:

Crude but interesting results...

Solarforce S1100, 3x18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

Comfy, are these good readings? I'm not familiar with this light. Also are you saying these are good cells or not? The reason I ask is because I actually want one for my HP, so it's probably a better deal for me than anyone. I will have to get the one in Reduk's link of course, but I presume they are the same. Marc.

It's just a runtime comparison between an unknown cell and a known cell in fairly new and excellent condition, the INR 15Q (1500mAh).

I have a Turnigy MAX80W on the way, maybe I can figure it out well enough to get some real data finally.

...


marcl
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comfychair wrote:

marcl wrote:
comfychair wrote:

Crude but interesting results…

Solarforce S1100, 3×18650 in series, w/low batt warning that trips at 3.3v/cell. Tailcap draw is 1.22A, current delivered to the emitter is 3.3A.

All cells fresh off the charger, start voltage of 4.21V.

Samsung INR18650 15Q, runtime on HIGH: 1h08m

BAK/CJ 6K00112, runtime on HIGH: 1h30m

Comfy, are these good readings? I’m not familiar with this light. Also are you saying these are good cells or not? The reason I ask is because I actually want one for my HP, so it’s probably a better deal for me than anyone. I will have to get the one in Reduk’s link of course, but I presume they are the same. Marc.

It’s just a runtime comparison between an unknown cell and a known cell in fairly new and excellent condition, the INR 15Q (1500mAh).

I have a Turnigy MAX80W on the way, maybe I can figure it out well enough to get some real data finally.

Ok, good stuff. Discharge test would be excellent. Looking forward to them.

Thanks,

Marc.

Eagles may soar, but weasels don't get sucked into jet engines!

ohaya
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comfy,

Got this pack in, but having a hard time finding somewhere to get “into” the pack. The one I have is sealed pretty tight all around? Where did you go in initially?

I was expecting that the connector would be the easiest place to start, but even that seems to be sealed up pretty good :(…

Jim

comfychair
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I think I had to chisel a starting point with the screwdriver, for sure it was one of the corners around the connector opening (doesn't really matter if you poke the circuit board, as long as you don't short anything). Don't remember to which side, though. I've already thrown out the plastics so I can't go back and reverse engineer it for you. Wasn't that tough, but I was using the magic pliers on them.

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ohaya
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Hi,

Ok, got the case separated.

What I did was use a pocket knife I have (a whetstone) and run it down the seams several time, to cut some of the glue or material down in the seams. The “back” seam, the one on the opposite side from the connector was actually pretty weak, so after I had done that a couple of times, I then took a flat head screwdriver, with about a 1/4” head, stuck it into the seam and twisted. That started spreading the seam. I did that across the back seam a couple of times, then the seam kind of popped open at a corner. I separated the sides my grabbing and pulling them apart (it wasn’t easy!).

I thought that once I had the two halves of the pack apart that it’d be downhill from there…. wrong :(!! The darn batteries are in quintuples, each with the + ends all tied together with metal bands/strips and the – ends all tied together with metal bands/strips, and each quintuple is GLUED with some white stuff, really hard, to the casing.

So there are 3 quintuples in the case, end-to-end.

Struggled with getting them up. I didn’t want to stick anything in, for fear of damaging the wrappers, so I kept trying to twist the casing, and, amazingly one of the quintuples, the middle one, kind of popped out of the casing. Then, one of the quintuples on the end I was able to pull out, but the last one (isn’t that always the case?) was a heck of a time getting it out, again, just kind of twisting the casing and pulling on the batteries.

Again, I thought I was on easy street… wrong!!

Now I had 3 quintuples of batteries with each battery in each quintuple bound to other batteries with metal strips, and these metal strips were kind of wide, and I was trying to figure out how to separate the batteries.

So I did what I did previously. I took a knife and carefully going in between the batteries, tried to cut the strips.

Then, SPARKS!! And, one of the batteries started feeling a little warm.

Ran outside, carefully dumped the quintuple into a ceramic container on our driveway (kind of reminded me of a couple of other thread on BLF the last couple of weeks). Thank goodness it wasn’t raining today!

Waited awhile then took a look. It turns out, I think, that the problem was that I had nicked the wrapper on one of the batteries, near the top corner on the positive end, and the metal connector that I was cutting on the + end must’ve touched that exposed area, probably causing a short:

I eventually got all 12 batteries separated, and the metal strip things removed… but wasn’t easy, and some of the batteries still have that white stuff stuck to them.

The main things were:

1) The glue holding the battery quintuples to the case

2) The metal strips/tabs connecting batteries within the quintuples was very wide, so it hard to get in there without possibility of shorting something or damaging the wrapper at the + end of the batteries.

3) My wife is kind of ticked off at me now for this little “adventure”, so this may be the last pack for me :(. Besides, I have like 25+ 18560s now :)… And that was not counting these 12.

comfy,

How did you remove that white stuff from the batteries. I think you mentioned some chemical, but is there any “normal” chemical, something that I’d have around the house, like alcohol, that can be used to remove it?

Thanks,
Jim

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Hi,

Also, a couple of the batteries sustained small nicks (very small… much smaller than the one pictured above), either on the top+ corner or somewhere else, of the wrapper. I don’t have any kapton tape or heatshrink. I had read that clear packing tape could be used to repair those, and was wondering if this is true?

comfychair
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The white stuff is just silicone adhesive, use a dull knife and/or fingernail. Just something that won't cut the heatshrink.

Look at my pic in the first post, with the three batches of four laid out. In that position, cut between each batch with scissors. Then with each batch, grab the tab with needle nose pliers, and roll it until it pulls the spot welds loose. Then unroll/straighten the bit you just pulled loose, get a new bite at it, and roll again. No need to separate the 4 cells before removing the tabs.

...


comfychair
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Yes 4 cells out of my 24 had spots like that at the top corners. I re-wrapped them. If the spots were down on the middle I'd say tape would be fine, but that close to the positive I'd only feel safe if they were re-wrapped.

84 cents. Get some. http://www.fasttech.com/products/1616/10001953/1140200-29mm-heat-shrink-...

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ohaya
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comfychair wrote:

Yes 4 cells out of my 24 had spots like that at the top corners. I re-wrapped them. If the spots were down on the middle I’d say tape would be fine, but that close to the positive I’d only feel safe if they were re-wrapped.

84 cents. Get some. http://www.fasttech.com/products/1616/10001953/1140200-29mm-heat-shrink-...

I’ve been meaning to get some anyway, but it’ll take at least 1.5-2 weeks to get here. Would tape be safe temporarily?

Also, for that heatshrink, is a hairdryer ok? I don’t have a heatgun.

Finally, when I order the heatshrink from FT, I’ll also get some of that kapton tape.

Thanks,
Jim

P.S. Do you think those nicks were already there on the batteries before extracting them?

comfychair
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Yes, the nicks were from when the tabs were spot welded, some of mine were on the inside of the group-of-four, no way it could have been done otherwise.

I don't know if a hairdryer is hot enough. I use a butane soldering iron with no tip screwed into the hole in the end, so it just blows hot air out the end. Endlessly useful thing to have on hand. (http://www.google.com/search?&q=ST250K)

I would tape up the damaged ones... and store them away somewhere safe until you get the heatshrink.

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ohaya
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comfychair wrote:

Yes, the nicks were from when the tabs were spot welded, some of mine were on the inside of the group-of-four, no way it could have been done otherwise.

I don’t know if a hairdryer is hot enough. I use a butane soldering iron with no tip screwed into the hole in the end, so it just blows hot air out the end. Endlessly useful thing to have on hand. (http://www.google.com/search?&q=ST250K)

I would tape up the damaged ones… and store them away somewhere safe until you get the heatshrink.

Hi,

FYI, the reviews on that heatshrink on FT says hairdryer works ok, but I understand.

Jim

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Yeah, it doesn't take a lot of heat, it's easy to overdo it with the torch and pop a hole in it. With the torch cranked down low it's great, quick enough that the cell never feels warm.

Funny thing about heat, whether it's soldering, or heat guns, or welding... sometimes a higher temp keeps the workpiece cooler, because you spend less time pumping heat into it. I've ruined way more stuff from using not enough heat than from too much.

...


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comfychair wrote:

Yeah, it doesn’t take a lot of heat, it’s easy to overdo it with the torch and pop a hole in it. With the torch cranked down low it’s great, quick enough that the cell never feels warm.

Funny thing about heat, whether it’s soldering, or heat guns, or welding… sometimes a higher temp keeps the workpiece cooler, because you spend less time pumping heat into it. I’ve ruined way more stuff from using not enough heat than from too much.

comfy,

BTW, I’m planning to try the discharge on one of the 12 tonight (one of the clean ones). Will post back. I want to try that setting to see if it doesn’t stop midway, anyway.

Jim

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I've done a top-up/discharge/charge/discharge on a few of them so far (before I got distracted by the Fujitsu packs) and the numbers don't look too hot. But this whole hobby charger thing is completely new to me, so I need to play some more before I know how the numbers I get relate to reality.

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comfychair wrote:

I’ve done a top-up/discharge/charge/discharge on a few of them so far (before I got distracted by the Fujitsu packs) and the numbers don’t look too hot. But this whole hobby charger thing is completely new to me, so I need to play some more before I know how the numbers I get relate to reality.

Sorry about the “distraction” :)… but it was a good one, right, I hope :)?

So what kind of numbers did you get, so we can compare?

I’m doing a charge on one of them now, and then I’ll do a discharge to 3.0V (since I got help here… I turned the safety time off, and will be watching it “like a hawk”, esp. after this afternoon’s “adventure” (sparks, smoke, and burning odor).

Will post back…

Jim

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I grabbed 5 at random to test but only finished 3 of them, but they did 1321, 1338, & 1340. 1A down to 3.0V. But, I haven't done discharge tests on any other brand/capacity cells to know how the numbers from the Turnigy relate to the advertised capacity.

Did you see the pic I posted in the other thread about the 'distractions'?

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comfychair wrote:

I grabbed 5 at random to test but only finished 3 of them, but they did 1321, 1338, & 1340. 1A down to 3.0V. But, I haven’t done discharge tests on any other brand/capacity cells to know how the numbers from the Turnigy relate to the advertised capacity.

Did you see the pic I posted in the other thread about the ‘distractions’?

Hi,

No, sorry. Which thread was that? I’ve been going blonky with all of this charging/discharging stuff :).

BTW, do we know what these from the pack are suppose to be rated at (too lazy to check)?

Jim

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ohaya wrote:
comfychair wrote:

I grabbed 5 at random to test but only finished 3 of them, but they did 1321, 1338, & 1340. 1A down to 3.0V. But, I haven’t done discharge tests on any other brand/capacity cells to know how the numbers from the Turnigy relate to the advertised capacity.

Did you see the pic I posted in the other thread about the ‘distractions’?

Hi,

No, sorry. Which thread was that? I’ve been going blonky with all of this charging/discharging stuff :).

BTW, do we know what these from the pack are suppose to be rated at (too lazy to check)?

Jim

Hi,

Re. distractions, was it post #94 on this thread (http://budgetlightforum.com/node/20513?page=1)?

If so, that’s a good kind of distractions, right?

Also, I thought another person on the other thread just threw the Fuj/Pana batteries into their i4 charger (so less than 3 weeks)?

Jim

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The first cell from the Fujitsu packs took 2901mAh on the first charge, haven't done a discharge test yet.

12 cells, 3 series sets of 4 cells in parallel, 9600mAh rating divided by 4 = 2400mAh.

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comfychair wrote:

The first cell from the Fujitsu packs took 2901mAh on the first charge, haven’t done a discharge test yet.

12 cells, 3 series sets of 4 cells in parallel, 9600mAh rating divided by 4 = 2400mAh.

Thanks. Our posts crossed, but I think I found the post/pic you were referring to, showing 2901 mAh :)..

Jim

P.S. Now you know what I’ve been going through the last couple of nights :)!

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