CS27 Ravat Blog‎ > ‎

Adding a Cranking Battery

posted Jun 25, 2011, 6:28 PM by Christopher Hubbell   [ updated Jun 27, 2011, 5:29 AM ]
I decided that given my intended power budget for Ravat, a dual house bank would be more appropriate than switching between battery #1 an #2.  Of course, this left me with the challenge of putting an additional big heavy battery somewhere.  But where?

First of all, it had to be on the opposite side of the boat to help offset the weight of the house bank a bit.  That reduced the problem by 50%.  It also needed to be near the engine so that I wouldn't need excessively large cables.  That narrowed the problem even farther and left me with the starboard cockpit locker.  The next problem is how to mount a flat battery against a curved hull.

This turned out to be relatively easy with a little rough woodworking.  I squared the tray to the cockpit locker divider and bulkhead.  To get the hull profile I put in a piece of cardboard and scribed a line on it.  After a little cutting I had a perfect template to cut from wood.  The tray would mount on the bulkhead via cleat, and be supported aft by the profile.  In the end it looks like this:

The black footmans loops are for the nylon webbing which retains the battery box.  I chose a West Marine SeaVolt flooded multi-purpose battery in a group 27 form factor.  It has about 3x the cranking amps my boat requires, which will be good in the fall when it gets colder.  That will go in tomorrow so I can start approximating the wire lengths.

I'm planning to get my cables from GenuineDealz.com as they only charge $1 per crimp.  That's a lot cheaper than buying a quality battery crimping tool, even with the number of crimps I'll be doing.