Onboard Battery Charger

A  few weeks ago before leaving on a fishing trip I went to test my boat and as I was turning the engine (be sure you have water running through the engine anytime you do this) smoke started to billow out of the console.
I immediately took out the fire extinguisher and sprayed down in the direction of what I thought was the source of the fire. I walked to the front compartment of the console where the other two batteries are stored and flames leaped a foot when I opened the compartment.
                      

Immediately after this mishap I inspected all batteries and found that only the cranking battery had been literally destroyed. I disconnected all wires from the batteries and connected one at a time to the battery switch and tried to turn on the engine. There was no reaction from either of the two batteries. I then took apart the switch and there was only a small “contact burn mark” on one of the plates. From there I went to West Marine and purchased a new switch for 52$. I realized that if I would have used the Red Laser ap I would have been able to buy the piece for as low as 30.94 from ManVentureOutpost.com but I wanted to go fishing that same day so….
I installed the new switch, turned the key and the engine immediately roared to life. I wonder how long this switch had been faulty and how much it has affected my starting.
On my third fishing trip I had accidentally left the battery switch on and my accessory battery had been drained to the point that after a short time out in the bay the battery was drained. I went on with the primary battery doing all the work.
Because of this mishap I decided to buy an on board charger and picked the Bass distributed XPS

XPS Bass Charger by Tackle Tour

I read a number of reviews regarding this charger and a few have warned that the charger runs hot. I plan to mount the charger in the front battery compartment and saw that the fiberglass wall is very thin at this spot. I expect the area if it doesn’t end up warping because of the heat it would probably begin to discolor. With this in mind I mounted the charger on a piece of 1/4 inch white starboard to act as a sort of heat sink.
In the meantime I have connected the batteries to the charger inside my garage. And it seems to work flawlessly. I’ve checked on the temperature and it’s not dramatically hot as described in the reviews. Perhaps they were describing a 3? bank unit.
I’m planning to be sure I have a deep cycle battery to run the accessories and a cranking battery strictly for starting the engine.
It’s the Salt Life Baby!