Dielectric grease?

The spray on type is way easier to use than the stuff that comes in a tube... And if you're installing a brand new hybrid battery and don't expect it to have any issues for 10 years or longer, I can see how it might be valuable in preventing corrosion.

However if you're replacing your first bad module or just cleaning up a healthy pack I'd recommend against it because next time you or some other unfortunate person in coming months or years will have a huge mess that will slow you down and make your hands/gloves and tools greasy and it's way harder to handle those little 8mm nuts too. There's simply not enough corrosion building up in months or a year or two to justify the hassle it creates.

 

We use the ‘little dab will do ya’ in telecommunications, and I would absolutely use it while playing ‘whack-a-mole’ with hybrid cells, or for other automotive electrical work.

NECESSARY?

Probably not, but neither is filling an oil filter before re-assembly.

ACTUAL mileage will vary.

 

Dielectric grease is an INSULATOR.
It was designed to be applied to the outside of connection points AFTER everything is put together.
You need to be careful of where and how you use it.

What Is Dielectric Grease?

 

Parts for what kinda project? I didn't see anything in your post that jumped out at me and said "battery rebuild".

I'm guessing you'll find the stuff most useful for connections that are exposed to weather, and the kind of pluggable connections that can experience fretting corrosion as they move slightly against each other.

 

.

Did you even read the article?
From the exact article that you quoted:
==========
Because when applied properly to electrical sockets, plug wires, or fittings with a good, tight mechanical connection, dielectric grease is a fantastic means to keep water and moisture out of your electrical system, prevents rubber gaskets from drying and cracking and seizing, and helps mitigate any dust or alkaline contamination that could cause corrosion and early deterioration of your wiring and connectors.


In short, dielectric grease isn't a gooey wire in a tube that when squeezed into a loose, ill-fitting connector will magically restore the flow of electrons. Rather, it seals and lubes and, as long as it's not forming a barrier between the mechanical connections, doesn't negatively impact the electrical system connections.
==========

 

Thanks to prius16 for fielding that one.

 

Yes. And what's more, I understood it.

"Applied properly" means after the connection is made.

There is no good way to know if putting it on the conducting surfaces will result in "a good, tight mechanical connection" or not
so the only right procedure is to NOT do that.

 

Fwiw, dielectric grease is not used as an insulator.
Dielectric grease has to be an insulator, so that it doesn't conduct electricity as it gets squeezed out of the fittings.

In fact, when used properly, dielectric grease, reduces the resistance between the connections, by preventing/reducing corrosion, arcing, etc.

As ChapmanF mentioned, dielectric grease is often used/required where humidity, vibration, etc.

 

Wrong, wrong, wrong!
Dielectric grease is used BEFORE the connections are made.

What's your background in Electrical Engineering and Mechanical Engineering and Material Sciences?
Mine is rock solid.

How many automotive, vehicle, military, etc products have you designed/specified?

When's the last time you refreshed your Mechanical/Electrical engineering materials courses/knowledge?

What professional papers have you read on topic? This topic easily crosses at least three main fields. So, there are plenty of professional papers to choose from.
Do you know the different types, and reasons, for dielectric grease?

Why do you know more than Military organizations of the world, and every single aquatic product manufacture?

So many questions..

As I mentioned in another thread.
I'm not a lawyer, nor a tax professional. I'm a geek researcher/engineer.

 

Have fun.

Code:

Google:
type:pdf dielectric grease

https://www.google.com/search?q=type%3Apdf+dielectric+grease

A quick one from the NHTSA:

Code:

https://static.nhtsa.gov/odi/tsbs/2020/MC-10179292-0001.pdf

Except:
========
Blue Grease in Battery Box
1. Clean battery terminals with a wire brush.
2. Clean battery terminals and battery studs with a liberal amount of electrical contact cleaner.
3. Dry battery terminals and battery studs with compressed air.
4. Apply dielectric grease to battery cable terminals.
5. Connect all battery terminals to proper battery studs.
6. Tighten battery terminal nuts to the proper specification 12 to 15 lb-ft (16.3 to 20.3 Nm)
The blue dielectric grease should be applied prior to assembly and torque.
Battery stud nuts are prevailing torque nuts, and should be replaced whenever they are removed.
========

 

i was at the parts store, and the guy recommended dielectric grease along with a new belt which had been slipping.
now i have grease all over my clothes. i don't think he knew what he was talking about, or was just upselling me

 

Dielectric grease was definitely not correct grease/lube to use.

They do sell, imho questionable, grease/lube for new or slipping rubber automotive belts.
Those lubes will do one, or two things.
Add friction to belt - think of fine sand glued to the belt.
Rubber conditioners/softeners, to allow the belt to better conform to the pulleys.

My guess is that it might have been a parts store person wasn't very knowledgeable. Many make minimum wage, and are there for well less than a year. It's very rare to see "professional" automotive sales people at the counter.

I know of two parts stores that do have "older guys with many years experience" at the parts counter. But, that's because the store is mainly a distribution hub, off a main road. And, they have a parts counter mainly for the occasional mechanic/person that needs something now.
Iirc, the parts store below is one of those stores.
(I went there for an exhaust pipe for my Olds.)
Carquest Auto Parts - Chelmsford Auto Parts, Inc.
301 Littleton Route, Rt 110 Rd,
Chelmsford, MA 01824
Phone: 978-256-6526 -- Closes 5PM


Dielectric grease, as it's name implies, is mainly for electrical connections.
On a high-level, it's a very custom, very specific formulation that is meant to fill in the "microscopic" defects in the metal contacts between electrical connections. By filling in the "pits" in the metal, that "exposed" metal is much less likely to start to rust/oxidize/arc/etc. Once metal starts to rust/oxidize/etc, that will spread. Eventually, it'll start to effect the metal to metal contact areas.
The dielectric grease is also specially formulated, so that on metal to metal contact areas, the "grease moves away".

The metal surfaces for electrical contacts are "full of massive irregular shaped areas". At least on "microscopic" level.
From a mechanical/material engineering point of view, every surface has "a roughness and a hardness" rating/specification.
Being to rough or too soft is bad. Being too smooth or to hard, is also bad.
Brake pads are great example of roughness and hardness tradeoffs.


Fwiw, in commercial fleet settings, they even have customized Dielectric grease for EV connections(evse).
The EV connections are a more specialized application, since the ~~3/4" electrical contacts are moved in/out many times a day.
When I looked about a year ago, I couldn't find anything near small sizes.
I just use good old Permatex Dielectric Tune-Up Grease for my EV connections.
Imho, especially since I use the ChargePoint charger at work. Using public EV chargers, is like playing "Cooties". You don't for sure, that a person that used the charger before, didn't have dirt, pollen, snow, rain, what ever in their ev charger port. And, then those cooties got on the Chargepoint charger electrical connections.

 

I predict this will provoke Sam to say "50+ years as an eet" again.

It's easy to slip into debating on those grounds, but tough to pull off; thing is, on an Internet forum, nobody really knows how long you've been an eet or how limp or rock solid yours is. Just building a track record in the forum of bringing the goods probably works better.

 

thats what electricians and i do, minus the tape

 

No dielectric grease needed for this application unless it'll be exposed to weather. In that case, dielectric grease would be inadequate. You would need a weatherproof splice connector with a silicone filled heat shrink tubing like what they use for well pumps. A liberal application of liquid electrical tape on a wire nut can work in a pinch, but not for really wet locations or connections that get moved around very much.

In fact, for low power usage, a properly done wire nut is one of the best connections around. A few things to keep in mind, though:

1. If it's stranded wire, twist the stripped wires together before twisting on the wire nut.
2. If it's solid wire, do not twist them together.
3. Twist hard enough for a tight connection, but not so hard you twist off smaller wires. Solid #12 takes a hard twist; stranded #16, not so much.
4. Always give each wire a solid tug to make sure it's well connected before you call it "done.".
5. Don't strip off so much insulation that the bare wire is exposed from beneath the wire nut.
6. Be sure to strip off enough that the insulation doesn't get in the way of the connection.
7. Use the right size wire nut for the size and number of wires. Too big or too small won't hold.
8. Putting electrical tape on a proper wire nut connection won't make it any better.
9. Putting electrical tape on an improper wire nut connection won't make that one any better either.

 

Each of these manufacturer instruction sheets say to apply it before the connection is made:

https://www.eaton.com/content/dam/eaton/products/medium-voltage-power-distribution-control-systems/reclosers/dielectric-grease-application-to-recloser-cable-instructions-mn280070en.pdf.pdf

https://static.dxengineering.com/global/images/instructions/ptx-22058.pdf

https://static.rshughes.com/wm/p/wm-asis/cba092258b3b523f7955035635cefbd075a657d2.pdf?uf=

 

It's called belt dressing, and is more of a sticky wax than grease.

 

My understanding is that a dielectric grease is a material that is neither a good conductor, nor a good insulator, that its its electrical resistance falls somewhere in between. You put a thin coat of dielectric grease on the metal parts of an electrical contact and then it allows current to flow through the thin surface coat while keeping oxygen and moisture away from the metal.

Am I wrong?