Battery Location

My new Hanse 301 has two batteries in the port cockpit locker, next to the gas bottle stowage.  This is obviously not the original position - the cabling looks like there was a battery in the shallow space under the aft bunk, port of the engine.  I would like to reclaim the cockpit locker for fenders/ropes and so want to move the batteries down below.  My questions are:

1.  Did the original battery really go in such a shallow space, with no apparent tie down and all sorts of pipes and cables going past it?

2.  What are the experiences of others in fitting two batteries?

The best solution that I have thought of up to now is to change to gel batteries, put the smaller (around 70-80Ahr) for the engine start back under the aft bunk.  Being gel, it can go on its side if necessary and does not need access for topping up, just as well as getting to it is a bit of a circus act.  I thought that the second (100Ahr) battery for domestics could be hung on the bulkhead in the aft cabin that is the aft wall of the heads.  This area is out of the way, would not affect use of the bunk.  Again, being gel means that there is no maintenance.  I could also screw an inverter and battery charger on this bulkhead.

Thoughts, comments experiences welcomed.

Paul

When I had a 301 I replaced the engine start battery with a small Red Flash battery and put the existing engine start battery in parallel with the domestic battery.  This doubled the domestic capacity.  The Red Flash is designed specifically for starting the engine.  An engine start battery doesn't require a high amp hour rating, just a high cranking power - to give a short burst of power.  Therefore it doesn't need to be as big.  The Red Flash batteries are ideal and you can slip one in next to the two existing batteries in under the aft berth.  I fixed up some shock cord around them for further security. 

http://www.dmstech.co.uk/redflash.htm

Update:  I have moved the battery location back down to under the aft bunk.  Following the tip on the Red Flash, I looked into the AGM battery technology and have gone for a couple of of them.  Engine start is 20Ahr and domestic is 100Ahr (though the cheaper AGM batteries from Squadron, www.batteries4leisure.co.uk ).  They can lie under the bunk on their side, need no topping up and have very little self discharge.  There is a lot of myths about their charging, so far the best advice that I can find is to ensure that the charging voltage remains under 15V (because of their lower internal resistance).  In this case, the diode splitter works in my favour as the voltage drop across it ensures that the voltage actually applied to the batteries is under 14 V.  I am also using a mains battery charge designed for Gel batteries, so it keeps to 13.75V.  All happy days.  The batteries are showing just over 13V at rest.  Next phase is to re-connect the wind generator and the Stirling Advanced Regulator thingy (switched to AGM setting).