Dielectric Silicone Grease

dagr51
dagr51 Solar Expert Posts: 72 ✭✭✭✭
Do any of you use it? Does it work to prevent corrosion on battery terminals? Do you apply it to each nut, washer and terminal as you are assembling the connection or do you first assemble and tighten everything and then apply the grease to the entire fitting? Thanks!

Dale

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Dielectric Silicone Grease

    Personally, I have used the anticorrosive red/green rings on my battery terminals for the cars... Works very well. I have also used the "paint on" anti corrosive liquid (again, made for batteries).

    I have not tried dielectric grease on battery terminals (my theory is that the acid will go around the grease and wick up/down the cable and still corrode--whereas the anti corrosive material "de-activates" the acid instead no matter how the acid got there in the first place).

    Where I have used dielectric grease is, for example, lamp sockets for (old junker) cars where the water gets in a corrodes the electrical connections for turn and tail lamps and lock the bulb in the housing).... The grease seems to prevent water from getting in pretty well.

    Your mileage may vary.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mwilsonnm
    mwilsonnm Solar Expert Posts: 26
    Re: Dielectric Silicone Grease

    Hello,
    I have used the dielectric grease for 7 years and have never had a corrosion problem. I apply it to the terminals before attaching the cables. Also, be sure to keep the batteries clean at all times. Mark
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Dielectric Silicone Grease

    The advantage of the silicone dielectric grease is that it won't melt and run when it gets hot, unless you are up around 400 degrees.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Dielectric Silicone Grease

    I don't personally like slathering silicon grease all over everything because it attracts dust and dirt--and is a mess to clean off...

    Another big reason to be careful with any silicon product (including spray lubricants) is around switch contacts and relays.

    The silicon vaporizes and gets in the contact points. And the minor arcing of the points and film can prevent them from working. The arcing (even very small arcs) can turn the grease into glass.

    This was found out years ago when telephone exchanges were primarily stacks of relays--a locksmith sprayed silicon oil on a door lock to the switch room of one... Eventually they had to remove and replace every relay because of it.

    A little silicon can contaminate an entire room/area.

    From Omron (a switch manufacturer download pdf file and search for silicon dioxide):
    If a switch is used in the atmosphere of silicon gas, arc energy may attract silicon dioxide (SiO2) to the contacts and contact failure may result. If there is silicon oil, silicon sealant, a wire covered with silicon, or any other silicon-based product near the switch, attach a contact protective circuit to suppress the arcing of the switch or eliminate the source of silicon gas generation. Even for a sealed switch, it may not be possible to prevent all of the gas from penetrating the seal rubber, and contact failure may result.
    In the end, I would be very hesitant to use dielectric grease for protecting battery connections.

    Many people place the grease on the mating surfaces then bolt together--hoping the grease will squeeze out of the contact areas. I would not recommend this as it may keep large/flat surfaces (i.e., mating surfaces) from making good contact because of dielectric grease entrapment. This may work OK for connections with high pressure (i.e., point) contacts (many slide/mate and "star lock" type washers).

    Since dielectric grease has no anti corrosion or other properties (drive out existing water and oxygen)--it probably has limited use to help preserve connections in a already "dirty environment". The grease may just seal the already existing contaminants at the junction.

    You can bolt contacts up first, then slather the grease on the outside surfaces--may help with some connections.

    If you are trying to make a reliable electrical connection (including switch contacts), a better product would be something like Deoxit.

    Or, for batteries connections, the anti corrosion stuff from the local auto parts/marine store would be fine.

    Lastly, batteries are sources of moisture and sulfuric acid mist (as well as hydrogen and oxygen). Batteries (including sealed/AGM types) should be well vented to outside air to reduce the risk of explosion and contamination of other equipment in the area.

    As always, this is my humble opinion... If something else works better for you...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Dielectric Silicone Grease

    Some folks use vasoline slathered on the terminals & cables, keep a roll of paper towels handy.
    I concur with the "avoid silicone" greases, they spread and creep, at times, they will creep into the joint of paint and metal, and over time, peel the paint off. I only use it on sparkplug boots, and base up ceramic (keyless) ceiling fixtures, on the bulb threads
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,