Pairing cells by grammage/weight?

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Pairing cells by grammage/weight?

I know that it would be best to measure ther capacity and to pair them like that (Im talking about same kind cells). 

But Im often too lazy for that or I dont have time.  

To measure how much they weight ismuch easier - is there some sense in that - thats my question. 

I mean, Im talking about trustfire flames -

If I have a pair wich weighs 67,9 and 68,0g, and other pair weighs 64,3 and 66,0 for example (this are numbers from my hghead, probably wrong), than it owuld be safer to use first pair, no? 

It would be safe to assume that first pair is "better paired",I mean, that they'll have similar capacity, and that they'll discharge simirarly... 

Stephen Wallace
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Joined: 06/25/2011 - 11:03
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Location: London, UK

It kind of sounds logical, but I really don't know if you can assume things work that way - I wouldn't want to do it without a lot of research first (in which case, you may as well spend the time doing some discharge capacity tests).

You could say that everything else being equal, the difference in weight must be down to the active constituents of the cell, and that being the case, weight should correlate to capacity. However, changes in weight could be down to an aluminium button being used in a batch of cells rather than steel, or a different brand of protection circuit, different case wall thickness, and so on.

I don't think that weight can be trusted as an accurate indicator of capacity.

Last seen: 2 years 3 months ago
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Stephen Wallace wrote:

I don't think that weight can be trusted as an accurate indicator of capacity.


Neither do I

Last seen: 7 years 3 months ago
Joined: 10/12/2011 - 15:18
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Location: Italy

weight don't indicate the capacity, panasonic 3100 weight less of my flames 2400, but may have sense for the same lot of battery need some tests and a know-how about batteries production to answer, anyway don't see reliable a pair with a weight difference of 0,5/1g

Last seen: 9 months 5 days ago
Joined: 05/07/2010 - 20:42
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Location: Seattle,WA

How much time does it take to test the battery vs weighting them :)
Weighing isn't accurate in any event.

Last seen: 9 months 5 days ago
Joined: 05/07/2010 - 20:42
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Location: Seattle,WA

Sorry. I misread your post. I thought you were just talking about checking (matching) voltages. I don't even have the capability of testing capacity.

I only have one two battery light however (dive light). I just keep a pair of same name brand and original capacity batteries and always use them in that light.

I just make sure the voltage is the same for each battery.

dthrckt's picture
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it is a good way to get a tighter group from a box of factory rifle cartridges lol

Vectrex's picture
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Weight is absolutely no indicator for capacity otherwise cells would loose weight over time as they get older. gorann ... I have to ask ... what gave you that rather unusual idea?

Chicago X
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Please do it in a multi-cell light, then report your findings.

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