# Re: [EVDL] Brass vs lead for automotive post connections



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Brass vs lead for automotive post connections*

Lead battery clamps tend to stretch and loss the contact pressure. You have 
to keep tighten them until the bolt ends touch.

Bare copper/brass connections will also corrode if not plated. The plating 
act as a bi-metal connection between two base metals.

I always used a zinc plated copper/brass battery clamps or use a gold plated 
ones where you install and forget about it for the next ten years.

I luck out and got gold plate ones for $1.75 each once they found out what 
it was going in a show and tell EV which gives them a ad.

Roland


----- Original Message ----- 
From: "enganear" <[email protected]>
To: <[email protected]>
Sent: Thursday, April 02, 2009 11:53 AM
Subject: [EVDL] Brass vs lead for automotive post connections


>
> I am contemplating the choice of brass vs lead for automotive post clamp
> connections for my 36V lawn tractor conversion. I have used brass 
> (without
> changing) for the last 15 years on an ICE starting battery with zero
> corrosion or other problems. Have I just been lucky? I do not anticipate
> ever pulling more than 100A and probably a LOT less. I never really liked
> lead because of corrosion, mushing at the clamp bolt, and oxidation at the
> post interface.
>
> Comments?
> Stephen Chapman
> http://www.evalbum.com/2502
> -- 
> View this message in context: 
> http://www.nabble.com/Brass-vs-lead-for-automotive-post-connections-tp22854720p22854720.html
> Sent from the Electric Vehicle Discussion List mailing list archive at 
> Nabble.com.
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
> 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Brass vs lead for automotive post connections*

Ok... so there is something more to it than the Galvanic series
(according to it,
gold should corrode against lead easily)... so what is it about gold
that makes 
it work so well? Can I use gold-plated connectors against aluminum?

-Thor


-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Roland Wiench
Sent: Thursday, April 02, 2009 3:44 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Brass vs lead for automotive post connections

Lead battery clamps tend to stretch and loss the contact pressure. You
have 
to keep tighten them until the bolt ends touch.

Bare copper/brass connections will also corrode if not plated. The
plating 
act as a bi-metal connection between two base metals.

I always used a zinc plated copper/brass battery clamps or use a gold
plated 
ones where you install and forget about it for the next ten years.

I luck out and got gold plate ones for $1.75 each once they found out
what 
it was going in a show and tell EV which gives them a ad.

Roland


----- Original Message ----- 
From: "enganear" <[email protected]>
To: <[email protected]>
Sent: Thursday, April 02, 2009 11:53 AM
Subject: [EVDL] Brass vs lead for automotive post connections


>
> I am contemplating the choice of brass vs lead for automotive post
clamp
> connections for my 36V lawn tractor conversion. I have used brass 
> (without
> changing) for the last 15 years on an ICE starting battery with zero
> corrosion or other problems. Have I just been lucky? I do not
anticipate
> ever pulling more than 100A and probably a LOT less. I never really
liked
> lead because of corrosion, mushing at the clamp bolt, and oxidation at
the
> post interface.
>
> Comments?
> Stephen Chapman
> http://www.evalbum.com/2502
> -- 
> View this message in context: 
>
http://www.nabble.com/Brass-vs-lead-for-automotive-post-connections-tp22
854720p22854720.html
> Sent from the Electric Vehicle Discussion List mailing list archive at

> Nabble.com.
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
> 

_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Brass vs lead for automotive post connections*

Hello Thor,

The conductivity of a element depends of the number of free spaces in the 
last electron orbit of a atom which is call the valiance orbit where the 
linking of these electrons occur. You can see the conductivity differences 
and effects in the Electro Chemical Conductivity Tables in a Chemistry 
Handbook.

I have done a lot of electro plating of these elements, so I have the 
references for this art form.

The electron count of a atom starting with the first roll of electrons is:

4 + 8 + 16 + 32 + 64 and so on.

Examples of common elements we use in EV systems:

Copper at 29 electrons has four rings of electrons that are 4+8+16 = 28 in 
the first two orbits and one in the last orbit which leaves
32-1= 31 free exchange spaces for electrons to link up. This makes copper a 
good conductor.

Zinc at 30 electrons also has four rings of electrons which is 28 electrons 
in the first orbit and 32-2 30 free electron spaces.

Therefore copper and zinc make a good match.

Lead at 82 electrons has four electron orbits at 60 electrons and
82-60 = 22 electrons in the fifth orbit leaving 64-22 = 42 free exchange 
spaces.

Gold at 79 electrons has four electron orbits at 60 electrons and
79-60 - 19 electrons in the fifth orbit leaving 64-19 = 45 free
exchange spaces.

Therefore Lead and Gold has a good conductivity exchange.

Looking at Aluminum at 13 electrons which has 12 electrons in the first two 
electron orbits and in the third orbit leaving 16-1 = 15 free exchange 
spaces.

Therefore the difference between Aluminum at 13 electrons and Copper at 29 
electrons if about two Aluminum atoms per one Copper atoms which causes a 
decrease of conductivity.

Gold with 45 free electron spaces in the valiance orbit would required about 
45/15= 3 Aluminum atoms per one Gold atom.

The closer in the count at the maximum amount of free electron spaces in the 
valiance orbit of a electron provides a better conductivity. If the count 
is very far apart, then there is less conduction or very little at all.

Roland








----- Original Message ----- 
From: "Thor Johnson" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Thursday, April 02, 2009 1:16 PM
Subject: Re: [EVDL] Brass vs lead for automotive post connections


> Ok... so there is something more to it than the Galvanic series
> (according to it,
> gold should corrode against lead easily)... so what is it about gold
> that makes
> it work so well? Can I use gold-plated connectors against aluminum?
>
> -Thor
>
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of Roland Wiench
> Sent: Thursday, April 02, 2009 3:44 PM
> To: Electric Vehicle Discussion List
> Subject: Re: [EVDL] Brass vs lead for automotive post connections
>
> Lead battery clamps tend to stretch and loss the contact pressure. You
> have
> to keep tighten them until the bolt ends touch.
>
> Bare copper/brass connections will also corrode if not plated. The
> plating
> act as a bi-metal connection between two base metals.
>
> I always used a zinc plated copper/brass battery clamps or use a gold
> plated
> ones where you install and forget about it for the next ten years.
>
> I luck out and got gold plate ones for $1.75 each once they found out
> what
> it was going in a show and tell EV which gives them a ad.
>
> Roland
>
>
> ----- Original Message ----- 
> From: "enganear" <[email protected]>
> To: <[email protected]>
> Sent: Thursday, April 02, 2009 11:53 AM
> Subject: [EVDL] Brass vs lead for automotive post connections
>
>
> >
> > I am contemplating the choice of brass vs lead for automotive post
> clamp
> > connections for my 36V lawn tractor conversion. I have used brass
> > (without
> > changing) for the last 15 years on an ICE starting battery with zero
> > corrosion or other problems. Have I just been lucky? I do not
> anticipate
> > ever pulling more than 100A and probably a LOT less. I never really
> liked
> > lead because of corrosion, mushing at the clamp bolt, and oxidation at
> the
> > post interface.
> >
> > Comments?
> > Stephen Chapman
> > http://www.evalbum.com/2502
> > -- 
> > View this message in context:
> >
> http://www.nabble.com/Brass-vs-lead-for-automotive-post-connections-tp22
> 854720p22854720.html
> > Sent from the Electric Vehicle Discussion List mailing list archive at
>
> > Nabble.com.
> >
> > _______________________________________________
> > General EVDL support: http://evdl.org/help/
> > Usage guidelines: http://evdl.org/help/index.html#conv
> > Archives: http://evdl.org/archive/
> > Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
> 

_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


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