Lead Carbon Batteries - a mistake?

Vsalva

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Hi all,

My sailing boat had two Mastervolt 130AH AGM batteries, a 115 amp alternator, and a Mastervolt IVO smart 12/50 mains battery charger. My usage is typically 1 to 3 day trips sailing solo, so I use the autohelm a lot. Recently, my batteries failed to hold charge and I tested them with a Stirling battery Tester which suggested they were at their life end. They are six years old. So I think I’ve had reasonable use out to them. I started to consider the replacement options, and decided to avoid lithium for the reasons quoted elsewhere on this forum. I then looked at lead/carbon, carbon/gel batteries as an alternative to AGM. The benefits seem to be a deeper depth of discharge, greater charging cycles, and faster charging. I dislike running the engine to charge the batteries in an Anchorage as I worry it’s intrusive to other people sharing the anchorage. Anyway I have bought 2 Victron 106AH lead carbon batteries, and am waiting for a third. However my concern is whether they will lead to excess load on the alternator, and whether the mains charger (programmable) is suitable or up to the job.
I don’t want to spark a debate on lithium, solar additions, wind etc so please don’t take this thread that way. I know these are all very well researched issues but just not for me at this time. I just want better educated opinions on the specifics of what I’m doing. Many thanks Vincent
 
No problem with the alternator, even with a third battery. Acceptance rates are higher when the batteries are heavily discharged, but in your type of usage you will be mostly replacing your usage at levels above 50% SOC when acceptance rates are lower nd well within the capacity of your alternator. Likewise your 50A mains charger is more than man enough.
 
No problem with the alternator, even with a third battery. Acceptance rates are higher when the batteries are heavily discharged, but in your type of usage you will be mostly replacing your usage at levels above 50% SOC when acceptance rates are lower nd well within the capacity of your alternator. Likewise your 50A mains charger is more than man enough.
Thank you for your swift reply. You’re right I’ve never discharged to below even 60% and I set a relatively high voltage alarm for low discharge levels. Thank you
 
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