[Star Catcher (Ted Dobosz)]

Hi Hemi

From what you say, the panel is quoted as being 12V output, so I assume there is an attached regulator that drops the open circuit voltage (18V) to 12V. The regulator is attached to the back of the panel. It typically has outputs for charging a battery and also outputs for a load e.g. like a fridge.

There is no restriction on panel size you can connect. A bigger panel will charge your battery faster. If the battery in your mount is 10AH then your 30W panel in theory (full sun, perfect temperature, 100% efficient controller etc) should charge it in 4.5 hours. A 60W panel will charge it in half the time, all being equal.

You can connect from the regulator's battery output terminals to the terminal/socket on the mount. I have assumed the battery in the mount is a 12V lead acid type, however it could also be a lithium type? If lithium, the charging profile from the panel's controller may damage the battery over time if maximum charged voltage level exceeds what is recommended for the particular battery type. If the controller applies a higher than normal voltage for extended periods, it will shorten the life of the battery.

More expensive solar charge controllers are smart enough to know if the battery is a wet cell, AGM, Gel, Cadmium and even lithium types. Some cheaper controllers can be manually switched to different battery profiles. It is highly unlikely this type of controller is integrated into your 30W panel.

Hope that helps.

Ted