Which baterry?

[Carioca]

I guess I have been lucky, as my 98' X has the original 2 blue top Optima batteries still working fine with no switches at all, but my fuse panel needs a change-out.Of course, I keep the boat on the hard after every sail.

[dlandersson]

Still good advice

Here is a copy and paste from a Practical Sailor newsletter that I recently received on their long-term battery testing progress. Thought the info here that might be useful to some...

..."Some old, and some new info here. We are well into the thick of an update of our 2006 test of “sealed” valve-regulated lead acid batteries also known as either gel or absorbed glass mat batteries. For the past several weeks, Rod Collins of Compass Marine has been cycling five different batteries through 30 deep cycles (to below just 50 percent state of charge) and then putting them on the charger for one hour to demonstrate just how quickly a cruising sailor can ruin a good battery. Even after just thirty of these cycles, some of the new absorbed glass batteries in our test never fully recovered to their pre-test capacity.

Although the full report will not be available to subscribers until mid April when the May issue of Practical Sailor is available, here are some tips that came out of our test that can help you prolong the life of your AGM battery.

Charge to full as often as possible, this point cannot be over emphasized.
Get back to at least 80-85 percent state of charge (full capacity) with each charge cycle and get to 100 percent state of charge as soon as you can thereafter.
Don’t regularly discharge your bank below 50 percent state of charge.
Size your most powerful charge source, usually an alternator or inverter-charger, for a minimum of 20 percent of bank capacity. Odyssey TPPL AGM’s prefer 40 percent of amp-hour capacity as minimum charge current.
Use smart chargers. Not all chargers that claim to be smart are in fact smart.
Use temperature compensated charging for all charging sources.
Use smart solar controllers. Some solar controllers start each new day at a new absorption voltage charging cycle. This is not healthy for AGM batteries that have low self-discharge and minimal parasitic loads when left unattended on-the-hook. Smarter controllers have a voltage trigger to pop them out of float mode. If they don’t drop to the trigger voltage they remain in float.
Using the correct float voltages are a critical aspect of AGM batteries. Chargers that use “dip switches” for programming often lack the correct voltages for both absorption and float settings.
Use an alternator temperature sensor and external regulator if possible. AGM batteries can demand a lot from an alternator and the heat created can shorten its life or cause premature failure.
For the best charging performance minimize the voltage drop in system wiring. Even a 3 percent voltage drop at 14.4 volts means just 13.96 volts at the battery terminals. Incorrect voltage sensing robs you of the fastest charging potential, especially during short duration, high current charging events.
Know your correct state of charge at all times. If this means investing in a battery monitoring device it will help in overall cycle life. If you are using voltage to determine state of charge be sure you are getting it as accurate as possible.
Avoid installations in engine rooms or hot areas of the boat. Heat shortens battery life." ...

-B.