Ultrafire torch - new problem

mathematics

My Ultrafire torch flashes and changes mode when riding on any kind of rough stuff - I am lead to believe this is due to the battery being loose and rattling around. Does anyone know if this is the case and if there is a fix for this?

This only happens with one of the torches - the other is fine. The batteries, incidentally, are the 18650 type.

Chris

supersonic

Wrap some paper around the battery and out it back in so is wedged in tight.

mathematics

supersonic wrote:

Wrap some paper around the battery and out it back in so is wedged in tight.

Great plan! Giving that a go - thank you

bartimaeus

The light changes mode because the cell moves and the contact is broken - that's how the clicky-clicky tailcap works. So wedge the cell in more securely - I use electrical tape - and if necessary add a spacer to the cell to make it 'longer'... I have some rare-earth magnets.

jimothy78

When mine started doing the same thing mid-ride, I bodged a fix by inserting a 5p coin behind the battery to take some slack out of the system.

mathematics

Next problem - I have some ultrafire 18650 batteries that are flat but the charger says they are charged, they defo have no charge in them - the wont operate the torch!!

Any ideas please? Are they shot?

jimothy78

mathematics wrote:

Next problem - I have some ultrafire 18650 batteries that are flat but the charger says they are charged, they defo have no charge in them - the wont operate the torch!!

Any ideas please? Are they shot?

Yeah, it happens sometimes. Of course, it could be the torch not working - have you ascertained that it's not at fault by using it with a different battery?

mathematics

yeah works with my other battery - the cells that wont take charge are protected - has that got anything to do with it?

jimothy78

cyd190468 wrote:

[There] are tests of the different brands of batteries from expensive ones down to cheap.

Any chance of a link, please?

bartimaeus

Torchy has what looks like some pretty decent info on cells and lights on his site... he's an eBay seller too, but the tests seem fair enough. http://www.torchythebatteryboy.com/p/18650-batteries-chargers.html

Ouija

mathematics wrote:

yeah works with my other battery - the cells that wont take charge are protected - has that got anything to do with it?

Had this happen with some 26650 Lion batteries. The protection circuit kicked in and i just couldn't get them to unlock the battery so i just cut off the protection circuit with a knife (it's only held on to the bottom of the battery by the outer shrink wrap).

mathematics

Thank you.

I trawled a battery forum and found that you can reset the protection by putting a paper clip + to + and - to - with a charged cell. Now the cells are charging!

jimothy78

Bartimaeus wrote:

Torchy has what looks like some pretty decent info on cells and lights on his site... he's an eBay seller too, but the tests seem fair enough. http://www.torchythebatteryboy.com/p/18650-batteries-chargers.html

Great link, thanks.

mathematics wrote:

I trawled a battery forum and found that you can reset the protection by putting a paper clip + to + and - to - with a charged cell. Now the cells are charging!

Also very useful information!