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ArcticMyst Security by Avery

Battery test 18650, comparator






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Shane;

This testing was done in Denmark by "HKJ" over in the Candlepower Forum.

It is a very good study of current #18650 cells.

It is amazing that the Panasonic 3400mah puts out 5A,

much longer than the high current "IMR" cells.

Larry
 
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Now, to be fair, the IMR holds its voltage higher for a whole 10 minutes before the Panasonic's capacity and therefore, lower dV/dt gives it the win. IMRs would still have their uses in other, more demanding applications, but now that we have much better, and higher capacity 18650s, the benefits of the IMR are kind of shadowed by the benefits of the new materials chemistry.

I think it's more amazing that the panasonic still measures over 3000mAh at that 5A discharge rate, probably close to 3200mAh if discharged to the low end of the datasheet discharge voltage. Most of the time, you get the full stated capacity at some stupid low discharge rate, while the actual capacity at higher rates drops.
 
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I think it's more amazing that the panasonic still measures over 3000mAh at that 5A discharge rate, probably close to 3200mAh if discharged to the low end of the datasheet discharge voltage. Most of the time, you get the full stated capacity at some stupid low discharge rate, while the actual capacity at higher rates drops.

I think the IMR cells are losing their advantages,

as newer NCR chemistry and nickel additives reduce IR,

and increase capacity in high demand applications.

Larry
 
Joined
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Messages
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I think they also have an HRL or BBQ or something like that, that increases resistance in the presence of a dead short, and it's a chemical based safety feature instead of an external circuit controlling the battery. I'm with ya, I kind of wonder how much longer IMR can last. Only use I can think of is for handheld power tools, and the newer Panasonics are getting close to being able to replace even those, I'd imagine.
 





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