Will magnets hurt Li-Ions?

[ja10]

I'm building a little external battery pack to test LEDs with, and rather than solder alligator clips to the + and -, I figured I could use a couple plastic coated rare earth magnets I have lying around. That advantage to using the magnets would be that the circuit could not be completed accidentally.

I tried using the search function, but got a database error the first time, and a white page the second time. Sorry if this is a duplicate question!

 

[James S]

magnets will not hurt a LiIon battery. Indeed it's regular practice around here to use tiny magnets to extend the flat top batteries so that they can be used in things that expect batteries to have a button on top.

 

[MrAl]

Hi there,

Magnets usually only bother circuit that have magnetic components, like
inductors or transformers, or something that depends highly on magnetic
fields to work like a standard computer monitor or tv set that uses the
cathode ray type tube.

In flashlights that use inductors in switching circuits, the magnet, if strong
enough, can bias the inductor into working farther into a particular quadrant
of it's BH curve than it was designed for, which may destroy the flashlight
unless some other feature happens to compensate.

In crt screens, it can cause unsightly color blotching in some areas of the
screen or even cause the shape of things displayed on the screen to become
distorted.

Magnets usually dont affect batteries however, unless they are moved back
and forth very close to the cell where they might induce an unwanted current
flow which could either discharge the cell eventually or cause it to become
overcharged, but this would be very rare.

 

[bfg9000]

Not to mention the magnet tipped leads sold here specifically for this purpose are perfect for such temporary connections.

 

[PEU]

The problem with magnets used as positive contact on flashlights is that they may move and create a perfect short circuit against the flashlight body... and if that happens only bad things can be expected...


Pablo

 

[bfg9000]

Such a problem has a simple commercial solution.

 

[Illum]

magnets will not hurt a LiIon battery. Indeed it's regular practice around here to use tiny magnets to extend the flat top batteries so that they can be used in things that expect batteries to have a button on top.

not that I know of, I use the tiny NdFeB magnets as spacers both in flashlights and in chargers...so far so good.

there has been cases where putting a magnet on a battery is said to cause self-discharge in alkaline cells but i hasvent heard of any on Lithioum-ion cells.

 

[ja10]

I'll go ahead and start using them. Since the batteries themselves are magnetic, I just wanted to be sure that I wouldn't be disrupting the internal chemistry.

Thanks for all the replies!

 

[Illum]

Since the batteries themselves are magnetic

erm....:thinking:

i don't know of any cells that comes magnetized...only under a huge magnetic field over a length of time could cells pick up small finishing nails.

 

[ja10]

erm....:thinking:
i don't know of any cells that comes magnetized...only under a huge magnetic field over a length of time could cells pick up small finishing nails.

Sorry, I meant to say "since the battery is ferrous", not magnetic - I think (is that the right term?) I think ferrous is typically used to describe iron's magnetic properties, but I'm not sure what other term to use. It's been too long since physics class.

My point was that I wouldn't have thought twice about keeping a strong magnet near a battery if the is was not attracted to the magnet. Since the material in the battery is attracted to the magnet, I wanted to be sure that the magnet wasn't disrupting the internal chemistry that creates the electricity. I'm not a battery guru (clearly), but I was imagining metal shavings or something being forced to one side, affecting battery performance.

Thanks for catching my error though - my mistake!

 

[Fallingwater]

No, they will not.