2000 H340 - anyone upgraded to AGM batteries? I am still running wet cells. Did you have to upgrade the shore power charger? What about the alternator? If so, any tips? Worth the effort??? TIA!
Hunter 340 AGM Battery Upgrade?
- Thread starter chschell
- Start date
I switched over to AGMs a year or more ago. Definitely worth the cost! Got tired of the cell maintenance. My Sterling ProCharge40 charger has a setting specifically for AGM batteries.
AGM technology is not best for boat use. Either standard flooded wet cells, 6V wet cells or lithium ion phosphate are the preferred choices.
Reason is AGMs do not do well in partial state of charge.
AGM Batteries - Making The Choice (from Maine Sail)
AGM Batteries - Making The Choice
AGM Battery Issues and the Blue Seas Dual Circuit Switch (from Maine Sail) "DARN AGM Batteries"
Darn AGM Batteries
Additional Observations on the Limits of AGMs Electrical Systems 101 - Page 3
Reason is AGMs do not do well in partial state of charge.
AGM Batteries - Making The Choice (from Maine Sail)
AGM Batteries - Making The Choice
AGM Battery Issues and the Blue Seas Dual Circuit Switch (from Maine Sail) "DARN AGM Batteries"
Darn AGM Batteries
Additional Observations on the Limits of AGMs Electrical Systems 101 - Page 3
Besides ease of maintenance, why do you want to change to AGMs?
AGMs will work, however, they are not as robust as flooded lead acid batteries.
It really depends on how the boat is used. AGM batteries do not live long lives if they are left in a partial state of charge. If the boat lives in a slip with shore power and a modern multi-stage charger of sufficient size, they will do OK. On a mooring? No way. Long term cruising with a stock alternator? No way.
A cruising boat will need a high output externally regulated alternator and lots of solar to keep AGM batteries charged.
Read the articles @Stu Jackson referenced, they will tell the story.
AGMs will work, however, they are not as robust as flooded lead acid batteries.
It really depends on how the boat is used. AGM batteries do not live long lives if they are left in a partial state of charge. If the boat lives in a slip with shore power and a modern multi-stage charger of sufficient size, they will do OK. On a mooring? No way. Long term cruising with a stock alternator? No way.
A cruising boat will need a high output externally regulated alternator and lots of solar to keep AGM batteries charged.
Read the articles @Stu Jackson referenced, they will tell the story.
If you are not able to maintain them, i.e., keep the charged, then they will be expensive dead batteries in short order. Nothing is really maintenance free.
If by maintenance you mean not needing to watch and refill water levels I agree AGM can be a good choice, but only with the right charging conditions as the others have said. Our house bank AGMs lived 8 seasons with no issues, and our engine and thruster batteries are still going strong in season 12. The only “maintenance” I do is to clean the posts once a year. Having said that ours live very sheltered lives. They sit on a shore charger all spring, summer, and fall, and are left disconnected for the winter. We do lots of day sails that bring them down to no worse than 80% SOC, and a handful of nights anchored out per year where they go closer to 50%.
We're on our second AGM battery set since converting over from wets. The first two 8D AGM set lasted twelve years. Other than when out on our extended (1-2 month) cruises each year, we keep the boat connected to shore power. While out, we have an 8KW Genset that we run for 1-2 hours every other day, bringing the house bank up to a minus 40 amps.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,923
Living in Racine you have to consider that LiFePo4 batteries do not like the cold winter months. You would either need to provide heat for them or remove them from the boat and store in a non-freezing space til sailing season. The good news is that they weigh only 20-30% of the Flood Acid batteries of the same capacity