Disassembly of GTL batteries

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
[size=+3]Disassembly of GTL batteries[/size]

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A few more batteries with ridiculous ratings for disassembly, as can be seen on the above image I also included a GIF battery (They are just as bad).



[size=+2]GTL 26650 12000mAh (White)[/size]

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Real capacity is around 2000mAh

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There is no markings on the can, but some corrosion.

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There is also corrosion on the top.

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The actual battery is not tightly wound and do not fill all the space.

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While opening the cell I cut the negative connection, part of the tab can be seen on lid.

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The usual construction a top, then isolation and then the can.

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Below the top is a metal film, this is usual the venting seal, but I have a suspicion that the metal used here is a bit too tick for that.

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The battery roll.

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With tape at the bottom.

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Here both the positive and negative connections can be seen.

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Trying to measure the surface of the battery . A bit difficult due to the wind.
The aluminium foil is about 82cm long and 5cm wide, i.e. 410 square cm, and both sides are used doubling the area. That is about 2.4mAh for one square centimeter.

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The battery is built from:
Negative electrode is copper foil with Graphite.
Separator
Positive electrode is aluminium foil with Cobalt/Nickel/Manganese (Depends on battery type), in this case it is most likely Lithium Cobalt Dioxide
Separator



[size=+2]GTL LS18650 10000mAh (White)[/size]

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Real capacity is about 500mAh.

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It do not look like there is much contents in this cell.

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Top looks fairly standard for cheap batteries, i.e. manufactured with a button top and a vent that probably will23-jul-2017 16:49 not vent.

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The battery roll.

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The two connections. The can connection split when I removed it.

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The aluminium is about 5cm Wide

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And about 22.3cm long.
That is about 111.5 square cm and about 2.2mAh for one square centimeter



[size=+2]GIF TR16340 2500mAh (Yellow)[/size]

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Real capacity is around 290mAh

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A easy cut and it is open. As usual the cell is not filled.

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The top is made the usual way.

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Including a thick foil as vent seal and a button top.

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The battery roll is out and it do still look partly filled.


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The copper foil is about 35cm long, but I did not get a good measurement of the aluminium foil.



[size=+3]Conclusion[/size]

It looks like many of the cheap batteries are directly manufactured for the consumer marked with the purpose of being cheap and bad.
Button top is not used in the professional market, there battery connections are spot welded to a flat top.
A pressure vent that will not work is also problematic. The batteries do not have any PTC or CID, high current batteries may be made that way, but not moderate current types.



[size=+3]Notes[/size]

Reviews:

GTL 26650 12000mAh (White)
GTL LS18650 10000mAh (White)
GIF TR16340 2500mAh (Yellow)

Other battery disassembly:
Disassembly of 9V LiIon batteries
Disassembly of USB charged batteries
Disassembly of UltraFire 9900mAh 18650 battery
Disassembly of some UltraFire batteries
Disassembly of cheap 18650 battery
 

Thetasigma

Flashlight Enthusiast
Joined
Nov 10, 2015
Messages
1,197
Location
Michigan, USA
Thanks for sharing sir, as usual this is quite informative and interesting. Have you done any disassembly like this on known good cells to demonstrate the difference?
 

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
Thanks for sharing sir, as usual this is quite informative and interesting. Have you done any disassembly like this on known good cells to demonstrate the difference?

Not really, but some of the Ultrafires (See links above) where made from worn down good cells.
 
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