Charging a magnetized battery is okay?

[hellokitty[hk]]

Hello.
Up until now, I've been charging my batteries with a hobby charger, and I've used three 1mmx1mm magnets in parallel to connect my LiIon and NiMH cells, hoping to reduce the resistance.
I just got a package of the 10mmx1mm magnets from dealextreme, thinking that those would be better, and easier.
I just tried them, and noticed the charging voltage is a bit higher than normal. I tried running 3A through a stack, and they got real hot real fast, so I'm guessing they actually have a pretty high resistance :(

I'll work on building a real charging cradle, but for now, I've come up with a solution that I haven't seen on these forums before. I took a large high strength magnet from one of those forever shakelights and stuck it to the side of my NiMH battery. It's strong enough that the charge leads will snap right onto the battery with nothing in between.
Looks pretty nice, and the resistance is lower, based on the charge voltage!

Since I've never heard of this before, is it okay to charge it when magnetized?

 

[Lynx_Arc]

Magnetism affects current flow so it is probably best they be kept at the ends (contacts of the battery rather than the middle of them. If a battery becomes magnetized but has no magnet on it the field created won't be very strong so it shouldn't have much of an affect on charging.

 

[xul]

This doesn't really make sense.
I guess you could run 3A through a load and see if moving the magnet close to the connecting wires affects the current noticeably.

 

[hellokitty[hk]]

This doesn't really make sense.
I guess you could run 3A through a load and see if moving the magnet close to the connecting wires affects the current noticeably.

What doesn't make sense?

Magnetism affects current flow so it is probably best they be kept at the ends (contacts of the battery rather than the middle of them. If a battery becomes magnetized but has no magnet on it the field created won't be very strong so it shouldn't have much of an affect on charging.

Yes I know...though...I mean, it's still going in the battery...I don't know.
I think it's still detecting the voltage properly, and terminating on cue.

 

[MorePower]

Magnetism affects current flow so it is probably best they be kept at the ends (contacts of the battery rather than the middle of them. If a battery becomes magnetized but has no magnet on it the field created won't be very strong so it shouldn't have much of an affect on charging.

Only magnets in motion will affect current flow. Moving magnets will induce a current. Since magnets used to hold charging leads in place are static, there's no need to worry about any sort of magnetic effect on charging.

 

[hellokitty[hk]]

Doesn't current through a wire count as movement?

 

[qwertyydude]

Physical movement is the only movement that really counts when magnetism is involved but even this would only register as mere millivolts and microamps compared to the large currents involved when charging a battery. And as far as impedance from electrical circuits, it'll only really be affected by AC and again it would be such a small effect as to be effectively non-existent, since this is a DC current none of it applies anyways.

 

[czAtlantis]

magnets can't affect charging. But magnet itself is insulator. The only conductive thing on the magnet is nickel coating which is veeery thin and has big resistance. Just sacrifice one magnet, smash it and you will see.

 

[xul]

Doesn't current through a wire count as movement?

I s'pose, but it's very slow.
http://en.wikipedia.org/wiki/Drift_velocity

 

[45/70]

Doesn't current through a wire count as movement?

It is the magnets that have to be moving, not the current/electrons.

Dave

 

[hellokitty[hk]]

Okay then, thanks.
This seems to work well.

 

[BoarHunter]

It is the magnets that have to be moving, not the current/electrons.

Dave

Wrong. Current flowing through a wire in a magnetic field will be subject to a force that will displace it.
But you would need a very strong current to have the wires fly :)


Off course, the use of magnet as contact will have no influence on charging except for the quality of the contacts.

 

[45/70]

Wrong. Current flowing through a wire in a magnetic field will be subject to a force that will displace it.
But you would need a very strong current to have the wires fly :)


Off course, the use of magnet as contact will have no influence on charging except for the quality of the contacts.

Well, LOL, were talking about two magnets on each end of a cell, inline with the current flow, I really don't see it having any effect. I mean, we're not talking about a toroid coil here.:crackup:

Dave

 

[400THz]

Doesn't current through a wire count as movement?

Of course it does! You were correct. ;)

Wrong. Current flowing through a wire in a magnetic field will be subject to a force that will displace it.

Also known as the Hall effect (although that term refers mostly to the voltage difference caused, IIRC).

Off course, the use of magnet as contact will have no influence on charging except for the quality of the contacts.

I agree.

 

[hellokitty[hk]]

Okay then, IMO this is better than using magnets on the leads. They really do have a bit of resistance.
Thanks everyone.

 

[BoarHunter]

Okay then, IMO this is better than using magnets on the leads. They really do have a bit of resistance.
Thanks everyone.

Magnets are fine, just use them to squeeze a proper eyelet to the battery terminal and not as contacts !!! Explained already in the past but people seems not to understand.

 

[hellokitty[hk]]

Magnets are fine, just use them to squeeze a proper eyelet to the battery terminal and not as contacts !!! Explained already in the past but people seems not to understand.

I don't understand O_O

 

[czAtlantis]

battery | thin copper | magnet. And this thin copper si connected using aligator clips to charger.

 

[Mr Happy]

battery | thin copper | magnet. And this thin copper si connected using aligator clips to charger.

As seen in the picture here, for example:
http://www.candlepowerforums.com/vb/showthread.php?262602-Analyzing-batteries-on-a-budget