Upgraded Battery Bank

When we purchased Emet, she had 2 wimpy little “marine” batteries.  One was the start battery and the other was the “house bank”.  Not too long after we moved aboard, the one that was the house bank shorted itself, outgassed, and died.  I was still in the process of reading and looking and deciding which batteries I wanted, so we replaced it with another cheapy “marine” battery.  I won’t go into all the details, but let’s just say that there is much to be learned about batteries.

I finally settled on the Trojan T-1275.  These things are chockablock full of lead.  Each one weighs a hefty 85 pounds.  I took the oldest of the two “marine” batteries I had and turned it in for the core charge and purchased 2 of the T-1275s from Continental Battery.  I moved the newest of the “marine” batteries to the start bank.

I had wanted 3 of the T-1275s, but the third just wasn’t in the budget at that time as I was purchasing the solar panels and charge controller and davits/panel mounts to make us electrically self sufficient.

So, the past couple of months, we would go to start Beaky (our Westerbeke 40 diesel).  I would switch to the start battery and . . . nothing.  Not even a hum.  I would have to switch back over to the house bank to start it.  Now, ALL of authoritative information on the web says that to be a properly equipped boat, you MUST have 2 battery banks:  start and house.  This is great in theory.  And I was all about going that route.  But our solar charge controller is a single bank controller.  The only way the start battery is maintained is if I put it in parallel with the house bank.  Well, guess what?  That defeats the purpose.  And I tried that for a while.  I would switch the battery selector to “both” and let the start battery get charged up.  Then switch it back to the house bank only.  And each time I tried to start Beaky:  nada.  So, I made a decision.  We were getting another T-1275 and I was going with a single bank.

The empty battery slot is where the old marine battery was and the new T-1275 is going.

So, Jodi made a day trip to turn in the old battery and purchase a new one.  She did good.  She only had to call once to see if Johnson Supply was Continental Battery.  And she got one of the red 2 watt battery cables.  *wink*  You can see it in the upper right of the pic all shiny and new.

The new battery installed.

With three batteries, we now have 450 amp*hours.  Well, a useable 100 on a daily basis.  You don’t want to drain your batteries to flat.  Nor do you even really want to use 50% on a daily basis.  We try to keep it under 25%.

The only thing left to do to the battery bank is secure them.  Right now they are held in place by the framing.  It’s all a pretty tight squeeze with mere fractions of an inch of clearance on the long sides.  Not an issue right now as we aren’t sailing in rough weather.  But, once we cast off the dock lines, I don’t want 255 pounds of lead and acid flying freely.

 

A Windy Night
Ship's Log

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