Dielectric silicone grease or carbon conductive grease? - Page 1
Forum section: electronics / general

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 13, 2022, 05:34:29 pm
content: Hello,Sometimes I stumble upon corroded and green battery contacts in different electronic devices at home.I was told that I should find dielectric silicon grease because it will inhibit corrosion and oxidation.Today I discovered conductive grease which said something like this:QuoteGoogle returned Amazon page with carbon conductive grease. It appears more suitable for above purpose becauseas opposed to dielectric silicone grease it improves conductivity by filling small scratches and pitts oncontacts while offering the rest of dielectric silicone grease's benefits.In my case I have a battery compartment that I used 800 grit sandpaper to get rid of corrosion and green stuffand cleaning with 99% IPA and likely caused scratches and pitts. I believe in this case carbon conductive greaseis the solution I should use now.I also have small electronic devices that require me turning batteries a few times to start functioning. Maybe dielectricsilicone grease would be more suitable in this case? Price-wise I think carbon conductive grease is 3x times more expensiveand maybe is more suitable for professional purposes or for use on delicate electronics. I don't know if carbon conductivegrease is improved version of conductive grease though.Maybe I should stick with dielectric grease because it is cost-efficient in my case?Thanks

author: Gyro
author_rank: Super Contributor
timestamp: January 13, 2022, 05:38:42 pm
content: A tiny dab of Vaseline on the battery tips works wonders. Cheap too.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 13, 2022, 06:56:05 pm
content: Quote from: Gyro on January 13, 2022, 05:38:42 pmDoes it have dielectric properties?I found 4 greases on AE:https://www.aliexpress.com/item/1005003130306629.htmlIs there low quality and good quality grease when it comes to buying from China?Any of them will do the job?

author: Gyro
author_rank: Super Contributor
timestamp: January 13, 2022, 07:46:44 pm
content: It depends what do you define as dielectric properties when it comes to a grease. It is non-conductive but works by excluding oxygen from the contact area, preventing oxidation and so, maintaining good connection.Vaseline is specified by some manufacturers of precision resistance boxes as a switch contact lubricant. I use it for such applications (low resistance switches and terminals). In a test I did on intermittent tapered plug contacts on a resistance box, without cleaning, it immediately restored stable low resistance.I wouldn't bother with products claiming to 'fill in the gaps' with conductive material for simple battery contacts - the current density isn't anywhere near high enough to require it. Your main goal is to prevent oxidation and corrosion of contacts with damaged plating and Vaseline is as good as anything at that job.If it doesn't work for you then simply wipe it off, no harm done. Silicone compounds are rather tenacious.

author: BrokenYugo
author_rank: Super Contributor
timestamp: January 13, 2022, 10:45:12 pm
content: I've always just used whatever oil/grease was handy, usually Vaseline or automotive wheel bearing/chassis grease and never had any issues, up to and including lead acid car/truck batteries. EDIT: I've also used actual silicone dielectric grease (e.g. Dow #4), and again, no connection problems, I think the stuff just squishes out at the actual contact point.

author: Benta
author_rank: Super Contributor
timestamp: January 13, 2022, 10:56:06 pm
content: Wouldn't "dielectric grease" kind of defeat the purpose?Anyway, go to your nearest car spares/tuning shop and look for "battery clamp grease". This does exactly what you want. Cost point: ~2...3$.Example:https://products.liqui-moly.com/battery-clamp-grease-3.html

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 14, 2022, 08:12:26 am
content: Quote from: Gyro on January 13, 2022, 07:46:44 pmI found this:QuoteFor lubing contacts vaseline is okay but if I want to lube seal in flashlight I will be better off with silicone grease?

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 14, 2022, 01:14:10 pm
content: Asked about silicone dielectric grease that I saw being sold on. 3M customer service and the reply that I received was contrary to what I learned about that grease. Said it doesn't affect electrical conductivity.

author: ajb
author_rank: Super Contributor
timestamp: January 14, 2022, 04:20:53 pm
content: Quote from: Boris_yo on January 14, 2022, 08:12:26 amIt depends on what the seal is made from, certain kinds of lubricants will damage certain kinds of seal materials. If the seal is silicone, then you likely do NOT want to use a silicone grease, because it contains solvents that make it grease instead of a lump of silicone can have the same effect on the silicone seal over time. So you'd want to refer to the specifications to verify compatibility. \Quote from: Boris_yo on January 14, 2022, 01:14:10 pmDielectric grease is used to seal out oxygen from the contact area to prevent corrosion, but shouldn't affect the conductivity of the connection because it's only displacing air, so what they said is correct. Any effect that the grease has on conductivity is indirect and long term, by preventing deterioration of the contact interface due to corrosion.

author: Boris_yo
author_rank: Frequent Contributor
timestamp: January 14, 2022, 07:40:00 pm
content: I foundthis interesting chartof specific manufacturer of lubricant materials and I wonder if it is universal or only specific to this manufacturer.It looks like some greases work well with silicones but others do not and only silicone oil works well with silicones.

author: G7PSK
author_rank: Super Contributor
timestamp: January 18, 2022, 02:54:24 pm
content: Quote from: Benta on January 13, 2022, 10:56:06 pmBattery clamp grease for car batteries contains something to neutralise acid, used to be sold here under the Holts brand as Nocrode which seems to be no longer available.