lithium house bank negative busbar green corrosion

[jvolpehoo]

My understanding is that if there is no battery acid involved then the green corrosion is galvanic. it has engulfed the cable terminal running to the engine ground. what to do?

For now I'm planning to replace the busbar whose surface is marred/etched, clean and coat the new connection with die-electric grease. if the corrosion has affected the copper inside the cable will also cut and re-terminate.

Also, is it OK to use the house bank while disconnected from the engine ground? the boat is on the hard and no grounding to water anyway. I'm using shore power via victron multiplus when doing yard work.

[wholybee]

Sounds like a good plan. There is no need for the electrical system to be grounded to water. Disconnecting the engine should also be fine, as long as there is currently only one wire to the engine block. If other stuff is connected to the engine block, then those things should not be used while the main negative cable is disconnected.

[jvolpehoo]

Thanks, if you can see these pics, the neg cable wires themselves coming from the victron inverter to the busbar is still tinned but the lug is halfway brown and untinned.

The main ground cable from the busbar to the engine block I will cut back to see how far the corrosion has gone.

Any idea what caused this only in these places? could it have been poor quality busbar?

When using die electric grease do I coat all surfaces of the lugs and busbar or only apply after they are bolted on?