18650 cells 1 year storage?

Trout River

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Yes if they are good to start with way over 76%
I've put some away @ 4.20 volts and over a year later 4.17 or 4.18 volts still
 

Trout River

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Probably I have never actually owned or used a 14500, 10440s are the closest I've had. They last a while charged.
 

sirpetr

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Yes. If its unprotected or good quality protected, then the discharge will be very low, surely will leave more than 76% charge in the cell. I dont have any numbers by my side, but I work with these li-ions everyday, so Im quite sure.
 

chillinn

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Many recommend, when storing cells for long periods, only charging them to ~3.7V-3.85V. I haven't heard an explanation for why, tho. But it sounds like OP is not storing cells so much as preparing them to be ready for use when needed, in a year if it takes that long.
 

sirpetr

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Many recommend, when storing cells for long periods, only charging them to ~3.7V-3.85V. I haven't heard an explanation for why, tho. But it sounds like OP is not storing cells so much as preparing them to be ready for use when needed, in a year if it takes that long.
Because this voltage is somekind of neutral voltage for the chemistry used and cells with this voltage age the less. There are two aging effects, if I recall right, one happen in lower voltages and one in upper voltage. Indicated voltage value is a compromise, sweet spot for longetivity.
 

ChrisGarrett

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I discharge down to 3.6v/3.7v if I'm not going to be using them for 3-4 months and they then go into the fridge.

Leaving them at 100% SOC for a year may rob you of 1-2% capacity.

Normal self discharge is in the neighborhood of 1-2%.

Chris
 

Duster1671

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Oct 16, 2017
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Here's an anecdote on li-ion capacity loss over time:

I bought a pair of AW 2600mAh protected 18650 cells in 2011. When they were new they measured 2400mAh actual capacity and after 10 years they were down to 2100mAh. Moderate use, mostly stored in a partially charged state.

Good batteries don't lose capacity very quickly unless they're used hard, misused, stored at high temperature, etc.
 

fulee9999

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Mar 3, 2021
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I have some Sanyo reds that I forgot about for more than a year, still over 4 volts ( 4.07 if I recall correctly ) from full charge
 
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