Why on earth... Samsung 33J 21700 3270mAh 3.2A

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mattlward
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Why on earth... Samsung 33J 21700 3270mAh 3.2A

I cannot think of a real use for this battery. The capacity is to low for a portable power bank, the continuous amp rating is to low for a flashlight and the milliamp rating may as well be an 18650. So, what am I missing here?

EDC rotation:
FW1A, LH351D 4000k (second favorite)
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Nichia 4000k sw40 r9080 (favorite light!)
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
S2+, XM-L2 T6 4C

Sirius9
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Price!?

 

mattlward
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Could be, but not a useful cell?

EDC rotation:
FW1A, LH351D 4000k (second favorite)
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Nichia 4000k sw40 r9080 (favorite light!)
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
S2+, XM-L2 T6 4C

djozz
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A quick google search tells that it has a great cycle life, which is not so important for flashlight use but in battery packs that is very important.

Sirius9
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Most batterypack powered devices like acu vacuum cleaner, BT speakers etc. use cheap not high capacity or high discharge cells.

 

HydrAxx
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Indeed, it is one of the best lithium-ion cells in terms of its life cycle (in a particular use context: Max Charge Voltage of 4.10v and Max Charge Current of 1600mA and Max Recommended Discharge Current of 1600mA too, Discharge Voltage Cut-Off at 3.00v, all for a total life cycle slightly above 2000 Cycles).

Otherwise I had the opportunity to test 2 cells of Samsung INR21700-33J of first revision(gray wrap) and 4 cells of second revision (a “2” is printed on the bottom left of the printing of the model, on the same line as the datecode and the PVC wrap color has changed: it is no longer gray but green now), the capacity of the 33J is about 3600mAh if we charge it up to 4.20v (instead of 4.10v, but by therefore goodbye the possible 2000 life cycles for rather 500 normal cycles).

In AC-IR, the internal resistance of the 33J (rev1) is about 27 ~ 28 milliOhms, while on the 33J (rev2), it is about 25 ~ 26 milliOhms, so slightly better (although common on a revised version).
In terms of continuous maximum discharge (by sacrificing the 2000 lifecycles of course), we can easily mount in 3C, that is to say about 10A Max Continous and the temperature of the cell does not exceed 55 ~ 60 ° c which remains a use without risk or premature wear.

Can a single flapping of a butterfly's wings trigger a tornado at the other end of the world?