I've habitually applied some 'liquid tape' then some spray-on silicone grease after connecting battery terminals. This seems to work within a flooded-leaded batteries life cycle providing you can keep the batteries out of inclimate weather.
Short story; I'll be making new connection and revisiting old ones.
Should I spray silicone grease on the affected connection after the soldered lugs have cooled down and before moving the shrink tubing up to position it and apply heat? Will this finalize the connection or is this redundant? It doesn't seem like its that much overcompensation or overspray even is it doesn't help but I don't want to do it if it hurts a waterproof connection. In addition, I want to see a corrosion problem; I don't just want to hide it.
I've got the ¼" shrink tubing, the 8ga lugs, the electrical grade solder and torch, the 8ga copper cable and a few can of silicon grade spray grease. FWIW, I also have some Lithium grease spray but I don't know if that is appropriate.
FWIW, this is an auxiliary battery connection. Truck battery positive through 70A isolator to 100AH battery via 3 metres of 8ga positive cable and short 8ga to a frame ground.
How should I proceed?