Right battery fastener material?

[PMF1984]

OK, I have lead posts with iron studs and copper wire with copper terminals. Or some of the terminals are tinned something from WM.

What is the preferred nut washer material/combination?

Copper washers yes, but copper nuts? Seems they might not stand up to torque. How about silicone bronze?

And what specific combos are bad?

Right now I have a stainless lock washer and a stainless nut.

 

[aboatman]

What you have now is what I have and is pretty common. I doubt your battery has iron studs though.

 

[RT Firefly]

Greetings,
Mr. PMF. What you're using is pretty well what I've been using for 20 years or so with no apparent problems. I use SS washers and SS wing nuts (snugged down with pliers). I think what is more important is to keep the connections tight and corrosion free. As Mr. a. inferred, I'm thinking steel or SS studs not iron.

 

[Comodave]

I used nylock S/S nuts on the studs so they won’t loosen up. All washers must be on top of any wires just beneath the nut.

 

[PMF1984]

Yes, steel, not iron.

 

[psneeld]

staonless has a bad rep for conductivity...although never a problem in my world.

Stainless is OK as long as the wire lug is in full contact with the battery terminal., just dont put stainless between them.

 

[kchace]

staonless has a bad rep for conductivity...although never a problem in my world.

Stainless is OK as long as the wire lug is in full contact with the battery terminal., just dont put stainless between them.

This:

Stainless isn't a very good conductor but the wire end should be directly against the battery terminal with nothing in between. If there is more than one wire they should all be in direct contact with each other. Top with a washer and a nylock nut. The washer and nut material don't really matter because they aren't really part of the circuit.

Ken

 

[C lectric]

There is nothing wrong with a regular steel bolt, but plated, and the same for the washers.

For blade type battery terminals use the CORRECT size of wire eye to match the terminal hole.

Do not put washers between the wire eye and the battery terminal. A good join depends upon the solid direct connection between the wire eye and the terminal.

Same for the round battery terminals.

Washers belong only under the nut itself.

And NO WINGNUTS.

FOr both use of a silicone grease or I like Nev R Seez both of which will exclude oxygen from the joint prolonging the time between cleanings by years. Don't need gobs of it and any excess will get pushed out leaving a metal to metal contact. Just clean up the squeeze out.

 

[Larry M]

Make sure the nut on the battery holding the ring lugs is torqued correctly. You can easily damage the battery. Trojan, as an example, lists all their torque values on their web site.

http://www.trojanbattery.com/pdf/WP_BatteryCableGuide_0512.pdf

 

[koliver]

It is also important to ensure there is no possibility of movement of the battery within its box, as that will put mechanical stress on the connection, flexing into the cables, terminal connectors, connections to the battery, loosening over time and potentially allowing dergrading of the connection itself, sparking, etc.
Wooden wedges are OK if clearances are slight, proper bracing if clearances allow over 1" of movement.

 

[HopCar]

I don’t know why so many marine batteries come with wing nuts. My preferred fasteners are bronze nuts, washers and lock washers. Easy to find at any good marine store and have a high copper content. I must admit I’ve also used stainless and not really seen a difference.

 

[dhmeissner]

https://marinehowto.com/battery-melt-down-narrowly-averted/

https://marinehowto.com/marine-wire-termination/

 

[Xsbank]

Never seize is not a good idea on a conductor of any sort, it is conductive and can migrate and cause a short which can cause all sorts of mayhem.

 

[TJM]

The GURU is correct. You do not want a conductive grease on a conductor.
Dielectric grease is best. Eliminates corrosion, most "corrosion" is electrical in nature. Whether it is galvanic or straight path.
I am glad nobody has mentioned WD-40, lol

 

[aboatman]

I wouldn't be putting dielectric grease between the battery terminals and the battery posts. We want the best conductivity possible here.

Putting dielectric grease on after the connection has been made is fine but the various sprays made for protecting battery terminals are easier and more thorough.

The wing nuts that came with your battery should be discarded and replaced with hex nuts.

 

[mike66]

http://www.crcindustries.com/products/battery-terminal-protector-7-5-wt-oz-05046.html
Works great. And definitely nothing wrong with stainless nut and washer, as long as they're tight.

 

[FF]

The highest terminal torque mentioned by Trojan was 180 INCH pounds .

Not a problem for copper nuts or washers.

 

[psneeld]

Right frpm the Permatex web site on Silicon Dielectric Grease use with battery terminals.

For connectors and battery terminals
1. Make sure the ignition system is off.
2. Clean surfaces with appropriate cleaner such as
Permatex Brake and Parts Cleaner or Battery Cleaner.
3. Coat both parts with grease.
4. Reassemble.

https://www.permatex.com/tech-documents-results/?doc_num=81150

 

[mike66]

Practical difference between copper and stainless in the thickness involved is nil. Time to focus on real problems. And don't forget to fuse those positive cables.

 

[RT Firefly]

Greetings,
Torque values are all well and good to know but who has a torque wrench graduated in inch/pounds handy? Rightly or wrongly, I simply snug-up my SS wing nuts, gently with pliers. Since my battery boxes are relatively accessible, I regularly check electrolyte levels and corrosion conditions. No problems in the last 20 years...But you never know. As Mr. 66 says..." Time to focus on real problems."

 

[ghost]

Greetings,
Torque values are all well and good to know but who has a torque wrench graduated in inch/pounds handy? Rightly or wrongly, I simply snug-up my SS wing nuts, gently with pliers. Since my battery boxes are relatively accessible, I regularly check electrolyte levels and corrosion conditions. No problems in the last 20 years...But you never know. As Mr. 66 says..." Time to focus on real problems."

Me. I do.

 

[RT Firefly]

Greetings,
Mr. g. I have inch/pound torque wrenches as well but not on the boat but as a result of this thread, I'm considering either buying or making a wing nut wrench.

 

[C lectric]

Never seize is not a good idea on a conductor of any sort, it is conductive and can migrate and cause a short which can cause all sorts of mayhem.

Hmmm! On a roll am I.

I should not have said Nev R Seez. I did mean No A Lox but also should have explained to use it ONLY on the larger terminals such as your battery connections and Large Busses. It is conductive, it is used industrially for alum. wire and copper connections and has its use aboard the boat but as explained above. Not anywhere near small connections or electronic equipment connections or plugs.

So to modify my post, I can't go back and edit, it is safest to use only a silicone grease, often referred to as a dielectric grease. That stuff is not conductive, will not cause a short will exclude oxygen and seal out moisture unless the connections are being bathed in, especially seawater. Keep your wiring DRY.

Just be carefull how much you apply as it can also make a mess. I often use a cotton swab or a lightly coated paper towel for bigger areas to apply a small quantity in a confined area. CLean up any squeeze out.