any known issues w/ U2 and 17670 battery contact?

just got a new U2, and my protected 17670 cells from AW won't work without a magnet on the (+) contact. Is this normal for the U2? My main question is, do the unprotected 17670 cells make better contact? If so, is there any circuitry inside the U2 to protect the battery, or do I need to monitor that closely myself.

I ask, because I'd rather not have to use the magnet, for fear of shorting something out, and it's just one extra little thing to lose at some very inopportune time someday. The less parts, the better. If I can get an unprotected cell to work w/o a magnet, I'd prefer that.

Do you have my new 17670 that has a button top?

Most probably the spring inside the bezel could not make a contact with the top of the battery. This happened with my U2. You'd need to extend the spring by pulling it with a small nose plier ...

SCblur,

does your U2 have the plastic sleeve?

or is your U2 version the one after the the version with plastic sleeve?

:huh2:

extend center spring , verify tailcap spring is touching an do not use the magnet(it may be causing the hall effect switch to screw up or worse touch the body and ground out)

The spring in the head (the + contact) isn't long enough to touch the top of the cell. Or maybe the button on the top of the cell is too short, assuming it has a button at all. Many li-ion cells are flat top.

I'd recommend gently stretching the head spring. But be careful, and don't pull too hard. A little stretch is all you need.

https://www.candlepowerforums.com/threads/104831

Hello AW,

They do have a button top, although it doesn't extend as far as a primary cell. I'm not sure if that helps.

AW said:

Do you have my new 17670 that has a button top?

Click to expand...

My U2 is the newest version. There is no plastic sleeve inside, and it WILL NOT accept 18650's, but 17670's fit quite well.

Luna, excuse my ignorance. Can you explain what you mean by causing the 'hall effect switch' to screw up? Also, if the cell did ground out, would it cause harm to the light, or the cell, or both?

Luna said:

extend center spring , verify tailcap spring is touching an do not use the magnet(it may be causing the hall effect switch to screw up or worse touch the body and ground out)

Click to expand...

I've tried pulling up on the spring, and I can get it to work intermittenly, but nothing that inspires any confidence. It'll work for a bit, then stop. I'm afraid to pull the spring any harder.

You probably will have to extend the spring up a little more on the bezel, and check the tailcap spring and the tabs inside the tailcap for a good connection. I ran into similar problems when I converted to 18650's.


Good Luck...I know it will be good soon!!!!!!

SCblur said:

I've tried pulling up on the spring, and I can get it to work intermittenly, but nothing that inspires any confidence. It'll work for a bit, then stop. I'm afraid to pull the spring any harder.

Click to expand...