Boat battery charging

[Sonlight]

I just purchased a Thunderbolt 13 watt briefcase solar kit and charge controller to charge my boat batteries. I also purchased a long connector cable. My question is than I cut the cable leading from the controller to the batteries and splice battery post terminal connectors for permanent mount instead of the clips provided without a problem? Also, there is a piece of equipment included in the box that the panels came in that is not identified in the user manual parts list. It has three spring clips on one side (positive and negative indicators) with red/green lights and a pin plug on the opposite side. Anyone familiar with this?

[Logan5]

The brief case solar kits are for charging phones and tablets. they are not meant to be permanently installed. 13 watts is not very much for a big boat battery, unless properly elevated this panel will likely only produce 9 or 10 watts. I would purchase a proper Marine grade solar battery maintainer.

[Wy_White_Wolf]

13 watts will not charge your boat batteries. It would be like trying to tow a 53' box trailer with a VW bug.

WWW

[PNjunction]

Before you cut it up, can you return it?

I'm a big fan of maintainers - as long as you know what you are doing. Unfortunately, many are foistered upon consumers that end up doing more harm than good unless they understand the system as a whole - and the difference between a maintainer and a charger.

Is your boat battery something like an 18ah agm used for light trolling? You might get away with it, and at that, only as a maintainer, not a real charger.

Running some 8D's or the like. Toss overboar... (um recycle!) or return. It's great that you have a controller, but at the end of the day, unless you have a fully charged dinky trolling battery to start with, that small of a solar system, (and the unknown specs of the controller) it can cause more troubles than it's worth.