Discharging Li-ion batteries

[RyeBread]

The best solution I could come up with in my dorm... This is safe, right?

 

[RyeBread]

Update: Bottle is now in freezer. Will check on it in an hour or so.

 

[oKtosiTe]

But why are you discharging a Li-ion cell? They actually take damage and may become unsafe from being overdischarged...

 

[akhyar]

Hopefully you light has low voltage protection or your batteries are protected

 

[KeepingItLight]

Update: Bottle is now in freezer. Will check on it in an hour or so.

I guess this will work. You could also rig up a fan to provide cooling during the discharge.

I have the Nitecore Digicharger D4. Although it cannot discharge a Li-ion battery, is has a convenient way to charge one up to 3.6 volts. That's a good storage level for the Panasonic NCR18650B and many other batteries. When the D4 is set for LiFePO2, charging stops at 3.6 volts.

I just received the LiitoKala Engineer Lii-500 charger/analyzer. It has a true discharge function. So do other analyzers. The new SkyRC MC3000 is one of the more interesting ones. I believe it can be programmed to stop a discharge at any voltage you like. (I do not own the MC3000. There may be some limitations I am not aware of.)

 

[RyeBread]

Thank you guys. The light and battery both had low voltage protection, and I took it out while light was still coming out. I may be looking into a new charger with a discharge function, so I appreciate the pointers.

 

[Cheapskate]

Thank you guys. The light and battery both had low voltage protection, and I took it out while light was still coming out. I may be looking into a new charger with a discharge function, so I appreciate the pointers.

You shouldn't be intentionally discharging them in the first place. They aren't NiMh, which are the type of battery that could develop a 'memory' and lose capacity. Li-ion batteries don't have this characteristic. With Li-ion batteries you should actively avoid fully discharging them to avoid damaging them and shortening their lifespan.