Single Lithium Ion Rechargeable (18650/16650 etc.) vs. 2+Primary Cells (CR123 for example) Safety Margin Question

cslinger47

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When it comes to batteries and current draw I am aware of the inherent safety issues with stringing multiple batteries together with radically different charges and how this can cause the magic smoke to appear and or the mini pipe bomb to go KaPop! With that said is using a single protected rechargeable battery any more inherently safe then stringing primaries together 2+ at a time?

For example, let's say I have a light that is 16650 compatible or useable that can also use a couple primary CR123's. Would the protected 16650 less likely to ever have an issue vs. the CR123 primaries?

Not that I see this as a huge issue as I have been doing this for a long time and never had an issue with 2 quality primary batteries, but I have also tended to lean more to single cell lights.

I have browsed this sight for many many years and may have posted in the way back with a long forgotten login but with the rise in popularity of 18650/16650/21700 etc. batteries my curiosity peaked. I have several 18650 lights and love them. All my questions center around protected cells of reputable manufacture only vs. reputable primaries not the cheapest ebay cells I can find. :D

Thanks all and take care,
Chris
 

Chicken Drumstick

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Not wanting to down play it. But I think sometimes people are a bit OTT with regards to li-ion. They are in loads of everyday household items, often running in series.

And lets face, petrol (gas) is highly explosive and very dangerous. Yet most people don't bat an eyelid about putting in their cars or filling up a can to put in the lawnmower.
 

cslinger47

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100% agree with you and this is more an academic question then one born out of fear per say. Like I said I've been doing this stuff for a long time and never had issue. Actually I think I had a mild outgassing with an akaline AAA one time A LONG TIME AGO but beyond that never any issues. Just a curiosity question that popped into my head the other day.
 

xxo

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A single protected 16650 should be safer than 2X CR123A because there is no way to mismatch a single cell. On the other hand, since it is rechargeable, the 16650 will have some inherent risks when charging, particularly if the cell is defective or has been over discharged but if the cell and protection are good and you are using a good charger, these risks are minimal.
 

roostre

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May 21, 2011
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... is using a single protected rechargeable battery any more inherently safe then stringing primaries together 2+ at a time?

For example, let's say I have a light that is 16650 compatible or useable that can also use a couple primary CR123's. Would the protected 16650 less likely to ever have an issue vs. the CR123 primaries?
...

The below article includes recommendations for avoiding potential issues:

 
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