Li-ion 18650s - A couple of quick questions.

[kris994]

I was going to buy a couple of AW protected rechargeable 18650s and an Ultrafire WF-139 charger.

I read the guide to li-ions at:

http://www.candlepowerforums.com/vb/showthread.php?t=161536

and it said leaving the batteries on charge too long will damage them, but the charger specs say that it will stop charging when the batteries are done. So does this mean it would be safe to leave them unattended if i needed to?

Also, I found these batteries for quite a bit cheaper but they are not protected and i have been told AW are the best brand, Should I avoid?

Battery pics and specs:

Batteries Specifications
[FONT=新細明體]。Cell Type : Li-ion
[FONT=新細明體]。[/FONT]Battery type : Ultrafire® 18650
[FONT=新細明體]。[/FONT]Capacity : 2400 mah
[FONT=新細明體]。[/FONT]Voltage : 3.7V
[FONT=新細明體]。[/FONT]Size: Ø18mm x 66 mm
[FONT=新細明體]。[/FONT]Weight : 43g
[/FONT]

Finally, in the basics guide i saw this:

"Do NOT rely on the protection to kill the flashlight when it is dead."

does that mean you have to switch off the light as soon as the batteries run out?

Thanks in advance!

 

[Coaster]

Unless you have a good charger and lights that are designed for them you probably want to avoid unprotected cells.

The cells from AW are a little more expensive but I've found that their sizing is better in many applications where other cells are just a bit too long. The reports are that they also have less capacity loss over time.

Even with protected cells and a "auto shutoff" charger you should still remove the cells as soon as possible when they are finished charging. Depending on the protection of the cell on either charging or discharging is a bad idea, it's just a safety backup.

You also don't want to run Lion batteries until the light goes out. Unless that light is designed for lions and has a low battery shutdown feature. Most lights will run the cells down until you hit the protection, not something that's good for the cell. Once you start to notice the light getting dimmer is usually when you want to charge the cells.

All of this IS covered in the link you posted also, you might want to re-read it carefully one more time.

 

[kris994]

Thanks for your time mate. I guess it's just me not understanding it very well..