My 1994 Hunter Legend 37.5 has two battery banks: two for starting (switch position 1) and three for the house bank (switch position 2). All of them are Group 27 Gel Batteries, type 8G27, rated at 86 Ah. They should be able to deliver 129 Ah (50% of their nominal 258 Ah). At anchor, during the day, the largest load is the Adler-Barbour fridge of about 6A. Assuming a worst case of 100% fridge duty cycle, that would be 129/6 or about 21 hours of operation before recharging. The batteries are about 7 years old. They are capable to 500 full discharges. Considering that most of the time the batteries are connected to shore power through the Freedom 25 Inverter/battery charger (with a Remote Control Panel), and only discharging to 50% when at anchor, I would assume that they should last for many years. However, when at anchor I have to run my Honda EU2000i generator now two to three times every day. I am assuming thus that the batteries amp-hours have substantially decreased and I am considering replacing them. I am thinking in replacing the three house bank batteries by four 6 V golf cart gel batteries. FYI, either bank1 or 2 have no problem in starting the Yanmar 3JH2-E engine. What kind of batteries would you recommend? AGM or GEL? The following are AGM: MK's AGM 8AGC2 (6V220AH) at $220; Trojan's AGM 8AGC2 (6V200AH) at $190; Universal Power Group's AGM UBGC2 (6V200AH) at $170; or Power Battery's Model PRC-6200s (6V200AH) at $160? Gel: MK's Gel 8GGC2 (6V180AH) at $250? Thanks for your help.
Selecting batteries for the house bank
- Thread starter Van737
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WOW!
Van: This is what I have been going through. 1. Do you do regular battery maintenance? 2. Do you have a 3 or 4 stage charger? 3. How important is the purchase cost of the batteries. 4. Do you have the space for a large battery array? I had 2 G31's Gels on my Hunter 31. They lasted for 10+ years. When they gave out I switched to AGM's and they have been in place for about 5 years. I used an Optima blue top for my starting battery. I also spent about 2-3 days out on the hook and ran the engine for maybe 45 - 60 min. once a day for preventative measures. The AGM batteries have higher storage capacities and GEL's last longer. If you don't care about the maintenance issues, then something like the Trojan flooded batteries may be the ticket. Most of the time batteries are not in a convenient location and maintenance free batteries are better. There are initially higher costs for Gel & AGM's but the overall cost for these batteries are less. You are going to get support for Sam's Club cheapo's but I see no value in changing out $50 batteries very 2 years when you can have a totally maintenance free solution for about $170/unit and they will last for 8-10 years. PS: The Yanmar is normally a very easy to start engine. I would suggest you have a starting battery that will start you engine if you run the house bank down. You really do not need 2 starting batteries. Move one of these to the house bank and increase your housekeeping bank.
Van: This is what I have been going through. 1. Do you do regular battery maintenance? 2. Do you have a 3 or 4 stage charger? 3. How important is the purchase cost of the batteries. 4. Do you have the space for a large battery array? I had 2 G31's Gels on my Hunter 31. They lasted for 10+ years. When they gave out I switched to AGM's and they have been in place for about 5 years. I used an Optima blue top for my starting battery. I also spent about 2-3 days out on the hook and ran the engine for maybe 45 - 60 min. once a day for preventative measures. The AGM batteries have higher storage capacities and GEL's last longer. If you don't care about the maintenance issues, then something like the Trojan flooded batteries may be the ticket. Most of the time batteries are not in a convenient location and maintenance free batteries are better. There are initially higher costs for Gel & AGM's but the overall cost for these batteries are less. You are going to get support for Sam's Club cheapo's but I see no value in changing out $50 batteries very 2 years when you can have a totally maintenance free solution for about $170/unit and they will last for 8-10 years. PS: The Yanmar is normally a very easy to start engine. I would suggest you have a starting battery that will start you engine if you run the house bank down. You really do not need 2 starting batteries. Move one of these to the house bank and increase your housekeeping bank.
I have three banks
I have on bank 2, 2, group 27 acdelco lead acids rated at 100 amp hours apiece, on bank 1, 2 group 24 agms rated at 50 amp hours apiece, and on bank 3, 3 group 24 agms at 50 amp hours apiece. the reason I still have the two group 27's are they are still good, and I run my adler barbour reefer unit off of them, My charger a promariner 3 bank 30 amp. The chargers settings are the same for lead acid as they are agms. So far it's been a year and I haven't had any problems, The group 24's are lighter so it's easy to move them if needed. and three of them cost about the same as two group 27's. I will probably end up buying 2 group 27 agms in the future to replace the two lead acids, just to see if there is any benefit to the 27's v's 3 24's. I run a stereo with three amps 1200 plus watts of power all weekend long along with the reefer system and ussually don't have to go to the third bank, just banks 1 and 2 turned on for house and reefer is hooked up direct to bank two. The reefer does draw from bank one when selected to all. Tim Welsh S/V Cabo Wabo Hunter 34
I have on bank 2, 2, group 27 acdelco lead acids rated at 100 amp hours apiece, on bank 1, 2 group 24 agms rated at 50 amp hours apiece, and on bank 3, 3 group 24 agms at 50 amp hours apiece. the reason I still have the two group 27's are they are still good, and I run my adler barbour reefer unit off of them, My charger a promariner 3 bank 30 amp. The chargers settings are the same for lead acid as they are agms. So far it's been a year and I haven't had any problems, The group 24's are lighter so it's easy to move them if needed. and three of them cost about the same as two group 27's. I will probably end up buying 2 group 27 agms in the future to replace the two lead acids, just to see if there is any benefit to the 27's v's 3 24's. I run a stereo with three amps 1200 plus watts of power all weekend long along with the reefer system and ussually don't have to go to the third bank, just banks 1 and 2 turned on for house and reefer is hooked up direct to bank two. The reefer does draw from bank one when selected to all. Tim Welsh S/V Cabo Wabo Hunter 34
Battery Selection
Some additional thoughts about the battery situation. 1) It's not a good idea to mix different types of battery chemistry. Go with all Flooded, or all Gels, or all AGM's. I prefer the AGM's because they require absolutely no mainteinance and they don't seam to be drawn down as quickly. 2) I don't believe that you are doing yourself a favor by dividing your house bank up. Battery life is substantially shortened by how deeply discharged they are allowed to get. For example, if you have a single 100ah house battery (50 usable ah)you run a risk of drawing that battery below the 50% threshold during the weekend anchoring. Even if you are careful to engine or generator recharge befor the battery is 50% discharged you are still drawing that single battery down to a level twice below that of a 2 battery (200ah) house bank, thereby decreasing the life of that single battery. You would be better taking all of those house batteries and making one giant battery which would be drawn down very little by comparison and therefore extending the life of all of the batteries. This assumes that they are all of the same type -Flooded, Gels or AGM's - and purchased at the same time, preferably of the same production run. The danger is that if one cell in one battery goes bad the others will suffer. This is another argument in favor of AGM's since they do not require water and do not gas or sulphate. The ideal system is to have a starting battery for bank one, and for bank two, as large a house bank as possible. Refer to Nigel Calder's "BOATOWNER'S MECHANICAL & ELECTRICAL MANUAL" for an in-depth discussion of this topic.
Some additional thoughts about the battery situation. 1) It's not a good idea to mix different types of battery chemistry. Go with all Flooded, or all Gels, or all AGM's. I prefer the AGM's because they require absolutely no mainteinance and they don't seam to be drawn down as quickly. 2) I don't believe that you are doing yourself a favor by dividing your house bank up. Battery life is substantially shortened by how deeply discharged they are allowed to get. For example, if you have a single 100ah house battery (50 usable ah)you run a risk of drawing that battery below the 50% threshold during the weekend anchoring. Even if you are careful to engine or generator recharge befor the battery is 50% discharged you are still drawing that single battery down to a level twice below that of a 2 battery (200ah) house bank, thereby decreasing the life of that single battery. You would be better taking all of those house batteries and making one giant battery which would be drawn down very little by comparison and therefore extending the life of all of the batteries. This assumes that they are all of the same type -Flooded, Gels or AGM's - and purchased at the same time, preferably of the same production run. The danger is that if one cell in one battery goes bad the others will suffer. This is another argument in favor of AGM's since they do not require water and do not gas or sulphate. The ideal system is to have a starting battery for bank one, and for bank two, as large a house bank as possible. Refer to Nigel Calder's "BOATOWNER'S MECHANICAL & ELECTRICAL MANUAL" for an in-depth discussion of this topic.
Mixing batteries is okay with the right stuff.
It is now okay to have different battery chemistries with the proper charging equipment. The Xantrex XC series 120vac shore charger allows for three different battery types to be charged with a single charger. Balmar also makes the DUO controller that allows the alternator to properly charge the different types. I would have to agree that it is a lot easier to stick with a single chemistry, but it is now possible.
It is now okay to have different battery chemistries with the proper charging equipment. The Xantrex XC series 120vac shore charger allows for three different battery types to be charged with a single charger. Balmar also makes the DUO controller that allows the alternator to properly charge the different types. I would have to agree that it is a lot easier to stick with a single chemistry, but it is now possible.
battery chem.
Steve is correct on both accounts, you can mix battery types with the proper setup, AND....it is much easier to go with like battery types (and safer, I think, for now until the technology has a track record).
Steve is correct on both accounts, you can mix battery types with the proper setup, AND....it is much easier to go with like battery types (and safer, I think, for now until the technology has a track record).
Question on mixing battery types
If you mix wet cell and gel cell battery banks I can see how you might set up the ac powered charger at the dock to charge the different battery types. But what voltage setting would you use for the engine generator voltage regulator? Wet cell takes a higher charging voltage than a gel, do you set the lower voltage so you don't fry the gel battery and never quite charge the wet cell battery?
If you mix wet cell and gel cell battery banks I can see how you might set up the ac powered charger at the dock to charge the different battery types. But what voltage setting would you use for the engine generator voltage regulator? Wet cell takes a higher charging voltage than a gel, do you set the lower voltage so you don't fry the gel battery and never quite charge the wet cell battery?
I charge banks seperatly
When running the engine Yanmar 3GMF with my stock 40 amp alternator, I try and charge my banks with the differen't batterys seperatly. Ive never purchased anything aftermarket yet for my alternator. Tim Welsh
When running the engine Yanmar 3GMF with my stock 40 amp alternator, I try and charge my banks with the differen't batterys seperatly. Ive never purchased anything aftermarket yet for my alternator. Tim Welsh
It all goes back to "how do you use your boat?"
For extended cruising and passage making go with the best or if maintenance is an issue. For day sailing and weekend coastal cruising reduce your starting bank to one battery and for house get two inexpensive group 27's deep cycle flooded cell batteries. With a Honda generator and a Freedom charger you will have plenty of power.
For extended cruising and passage making go with the best or if maintenance is an issue. For day sailing and weekend coastal cruising reduce your starting bank to one battery and for house get two inexpensive group 27's deep cycle flooded cell batteries. With a Honda generator and a Freedom charger you will have plenty of power.
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