18650 battery question

davemp

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I have a Streamlight HLX that I'm using 2600mah 18650 batteries in. My question is, how much run time will I gain by switching to 5000mah batteries? davemp
 

flatline

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Well, if the listed capacity is correct for the 2 cells, you should get about 1.9 (aka 5000/2600) times the runtime with the 5000mah cell as with the 2600mah.

--flatline
 

Lynx_Arc

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I have a Streamlight HLX that I'm using 2600mah 18650 batteries in. My question is, how much run time will I gain by switching to 5000mah batteries? davemp

You may see a drop in runtime as there is no such thing as a 5000mah 18650 battery and people selling them as such you may find yourself duped into buying a 1200mah battery with a label claiming otherwise..... The highest capacity 18650s are 3400-3500mah at this time.
 

davemp

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Thank you. Is there any downside to using the 5000mah battery? davemp
 

parametrek

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"If the listed capacity is correct" is a VERY big if. A 5000mAh 18650 doesn't exist. The highest capacity are 3500mAh or maybe 3600mAh if you are very rough on the cell.

Usually these cells that egregiously overstate capacity add an extra digit to the real capacity.

edit: Lynx you are too fast :)
 

alpg88

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Thank you. Is there any downside to using the 5000mah battery? davemp

depends, in most cases they have very little capacity, and die after a dozen of cycles, if you lucky, in some cases they blow up and can cause a fire or a serious injury
 

Lynx_Arc

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Any cell maker using 5000mAh on their 18650 shouldn't be trusted as a rule, but that's just me?

Chris

It isn't you as even if the cell isn't bad the price you pay for what ends up low capacity often isn't worth it as a ~1000mah 18650 ends up being set aside as a "last use" cell when you have many of them it never gets used and sits around as wasted money. If by chance it happens to be a 2000-2600mah cell it still may end up being an average price for a cell and those wanting a large capacity cell will soon replace it with a 3300mah+ cell and it will end up being used in something else (or not at all).
 
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davemp

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My bad. I meant to say 3400/3500 mah not 5000. Would there be much increase in run time using the 3400/3500 cells? davemp
 

alpg88

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yea it would be, by 800-900mah. that is about 30% also keep in mind some 18650 are not 4,2v but 4,35v and they calculate capacity based on that, not all chargers will charge to 4,35v so if you have such cell, and 4,2v charger you will lose 100ma or so
 

ChrisGarrett

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yea it would be, by 800-900mah. that is about 30% also keep in mind some 18650 are not 4,2v but 4,35v and they calculate capacity based on that, not all chargers will charge to 4,35v so if you have such cell, and 4,2v charger you will lose 100ma or so

There aren't too many 4.35v cells (from quality manufacturers) out there any longer. Even back then, LG made the D1/E1 and they were only 3000mAh/3200mAh and then Samsung made their 18650 of similar capacity and Sanyo had their 2200/2500mAh 16650s.

Chris
 

Lynx_Arc

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I once ordered an 18650 portable fan that came with a 2600mah battery that tested out at about 1100mah. I wasn't upset though as the price of the fan was cheaper on ebay than other dealers selling the same fan without a battery.
 

jeff51

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