18650 charging4.

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18650 charging4.

yesterday I tore open a battery pack from an old laptop.

 

the battery pack said it was 10.8V and google said the model number was 4400 mAH. 

 

I was told:

If that’s the case, they are 3.6V at 2200mAh each. 3 in series, 2 in parallel for a total of 6.



I threw these on a charger, my charger has a cut off at 4.2V with the protected 2600mAH 18650's I've been using. 


I haven't had any of these batteries charge higher than 4.16V after several hours on the charger. I put one in my flashlight and it seems to be doing as good or better than my other (expensive) batteries I bought from monsterflashlights.com. (Which may be getting wore out I charge them and use them daily.)


question is, is there a difference between the 3.6 and 3.7v batteries? I assumed they all charged to 4.2? 

hank
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and what, if anything at all, is written on each cell?

and did you read this?
http://batteryuniversity.com/learn/article/lithium_ion_safety_concerns

P.S., no reason you should trust my opinoin, I’m just some stranger on the Internet.
This search may answer your question, if you pick and choose which result you pay attention to.
Most of them look right to me:

http://www.google.com/search?q=“lithium-ion”+“3.6v” “3.7v”

WarHawk-AVG
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Got pics of the batteries, marking on batteries

I would probably guess they are Sanyo red cells w/ the red ring on top, the 2600mAh have the blue

As long as the voltage of the individual cells were not too low below 3vdc then they will charge just fine at 4.2vdc, termination voltage is dependent on the CC/CV charge pattern

What expensive batteries did you get from monster?

OMG!!! I just looked at their prices…not no but HELL no…daggum!
First of all they are re-wraps, a 14500 for $8~ good grief!
A re-labelled C8 for $65~ cmon this dude is robbing people blind!

Otanacious
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zoom zoom wrote:

question is, is there a difference between the 3.6 and 3.7v batteries? I assumed they all charged to 4.2? 

From Battery University

Battery Uni wrote:

The nominal voltage of lithium-ion had been 3.60V/cell. This is a practical figure because it represents three nickel-based batteries connected in series (3 x 1.2V = 3.6V). Some cell manufacturers mark their Li-ion products as 3.70V/cell or higher. This poses a marketing advantage because of higher watt-hours on paper (multiplying voltage times current equals W). It also creates unfamiliar references of 11.1V and 14.8V when connecting three and four cells in series. Let this higher voltage not cause confusion; equipment manufacturers will always adhere to the nominal cell voltage of 3.60V for most Li-ion systems, and the standard designation of 10.8V and 14.4V will always work.

How did this higher voltage creep in? To calculate the nominal voltage, we take a fully charged battery that measures 4.20V and then fully discharge it to 3.00V at a rate of 0.5C while plotting the average voltage. For Li-cobalt, the average voltage comes to 3.6V/cell. Performing the same discharge on a fully charged Li-manganese with a lower internal resistance will result in a higher average voltage. Pure spinel has one of the lowest internal resistances, and the plotted voltage on a load moves up to between 3.70 and 3.80V/cell. This higher midpoint voltage does not change the full-charge and end-of-discharge voltage threshold.

zoom zoom
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They say LG Chem on the + side too, but here's a pic of the battery itself. I am not good with colors, but I'd say it's a beige wrap? Looked yellow yesterday in low light conditions when I took them out.. Came from an old apple iBook.

http://i60.tinypic.com/11t3fxs.jpg



not sure how to attach a pic here yet this is a different post editor than any I'm used to.

Otanacious
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Datasheet for the ICR18650S1, ~11 year old cells!

Edit: Datasheet is for the S2, not the S1, I suppose the S1 variant is more older!

hank
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There’s no difference between a claim of 3.6 and a claim of 3.7.
Old cells are likely not worth much effort.
You’ve been way overpaying for stuff buying from Monster.
Take a look at what’s offered at mtnelectronics.

What charger are you using?
You’re taking the standard precautions with where, and when, and how you charge, assuming you have a safe charger?
You know not to inhale if a cell vents?

Basic stuff. Worth spending some time reading.
Just another interested amateur here. You’ll get varied opinions.

zoom zoom
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haha 11 years old!!! These were brand new state of the art never need another when they were first sold. 

I'll run a couple through a few cycles and see how they do. If I gotta pitch em it's not a big loss or anything, worth a try. 

 

I have a cheap charger but it's been good to me, always cuts off at 4.2. I plug it into a surge protector in a metal building that stays warm even tho nobody's usually around, not much in there that would catch fire.

snakebite
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that control panel looks familiar…
btw we know not to expect much from really old batteries like those but have been surprised a few times.
as mentioned the monsterflashlights.com stuff is waaaay overpriced.
and the batts are in the “whateverfire” class.
yes old laptop pulls are often better.
welcome to blf!
another ohioan spotted

WarHawk-AVG
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and yes…welcome to the forum zoom zoom