what is the easiest way to discharge single 18650 Li-ion cells?

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Hot Brass
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what is the easiest way to discharge single 18650 Li-ion cells?

I have a few single near full 18650 Li-ions that I would like to discharge(run down) for storage and be able to monitor the voltage with my DVM,so obviously installing inside the light and turning on won’t work. Can I rig up something using a battery holder and maybe hooking up a bare bulb in between the + and -?. I want to be able to monitor the voltage as it’s running down. Something easier? Thanks,HB

LowLumen
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A 10 Ohm 10 watt power resistor would drain at about 400mA rate.
V/R=I
4V / 10ohm = .4 Amps.

comfychair
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Monitoring the voltage while it's running against a load won't tell you much, you need to know the open circuit resting voltage, so just run them in a light and remove to check the voltage every 10 minutes or so. After 1 or 2 you'll have an idea how long it takes to drop how much voltage, so you won't have to stop to check as often.

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WarHawk-AVG
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Hot Brass
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Thanks to all who responded! That battery University link is great! HB

hank
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Followup question from the Poll (left sidebar) “how do you store your batteries?”
http://budgetlightforum.com/node/54889/results

Which favorably viewed chargers have the “lithium battery storage” function?

When I have cells to store, I’ve been running cells down, then charging them at the 3.2v/LiFePO3 setting (Xtar VP2 charger) and figuring that’s about right for storage voltage.

But it gets tedious that way.

flydiver
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3.2v is on the low side if shooting for50%.

I don’t know of anything but hobby chargers that have storage function. It would be great if one did.

RobertB
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Seems like it would be a simple addition to have a “storage” function on something like an opus charger, that would discharge or charge to 3.6v.