I remember seeing but cannot recall how much an AGM batteery is dischaerged at specific voltages. I believe my 3 battery (optima ) house bank is discharging too rapidly from it's full 12.5V state. also seems that optima batteries are now hard to find and not as well thought of . Any outstanding other choices?Thanks!!
How low can you go..Discharge prohile for AGMm batteries
- Thread starter Mark Juetten
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Optima, or Enersys the inventors of the Optima battery, used to publish this. Enersys sold the brand to Johnson Controls and Johnson Controls has pretty poor support for this type of documentation.
12.5 volts is not full on Optima batteries. Resting voltages on most Optima deep cycles I see are above 12.75V and as high as 13.1. If your batteries are only getting to 12.5V, resting open circuit voltage, they are likely in rough shape..
12.5 volts is not full on Optima batteries. Resting voltages on most Optima deep cycles I see are above 12.75V and as high as 13.1. If your batteries are only getting to 12.5V, resting open circuit voltage, they are likely in rough shape..
Re: How low can you go..Discharge prohile for AGMm batterie
I chose optima because I could fit 3 batteries in the comprtment on our 376. I'm thinking I'll be looking for 3 new AGM. Battery bank got so low after a day of sailing with gps and instrument on tht ancor light would not light until I started engine and charged system.
I chose optima because I could fit 3 batteries in the comprtment on our 376. I'm thinking I'll be looking for 3 new AGM. Battery bank got so low after a day of sailing with gps and instrument on tht ancor light would not light until I started engine and charged system.
Re: How low can you go..Discharge prohile for AGMm batterie
Mark:
My friend with a 376 just replaced his batteries with 8D's from Batteries Plus. They fit under the port/starboard settees.
Mark:
My friend with a 376 just replaced his batteries with 8D's from Batteries Plus. They fit under the port/starboard settees.
How long did these last?
How do you use the boat?
Mooring or dock sailed?
What shore charger?
Solar or wind?
What alternator do you have, size etc.?
Alt temp sensor?
How many Ah's /day are you using?
Do you have a battery monitor?
Re: How low can you go..Discharge prohile for AGMm batterie
They lasted 4+ years. Moored to dock and charge only when we're present with a Xantrex charger set for AGMs. Alternator is OEM. Don't know if te sensor. Ah is norml. No refridge. just instruments and house lights. No solar etc. no batt monitor only voltage and amp hr gauges that are not accurate. I notice if I turn the chargeer off house lights immeditely dim. We anchor out often. WE have honda 2000 genertor as a bach up. The Chrger pretty much runs constantly dockside. Also have an isolated flooded starting battery which seems to be immortal.
They lasted 4+ years. Moored to dock and charge only when we're present with a Xantrex charger set for AGMs. Alternator is OEM. Don't know if te sensor. Ah is norml. No refridge. just instruments and house lights. No solar etc. no batt monitor only voltage and amp hr gauges that are not accurate. I notice if I turn the chargeer off house lights immeditely dim. We anchor out often. WE have honda 2000 genertor as a bach up. The Chrger pretty much runs constantly dockside. Also have an isolated flooded starting battery which seems to be immortal.
What should i check
Going to the boat this weekend. Wondering how to decern if these batteries are cooked or if one battery is bad? I'll try and calibreate my meters with actual measurments across the batt. terminals. I understand they should charge up to 13.1 ++ but how fast should they discharge to ??. Thanks
Going to the boat this weekend. Wondering how to decern if these batteries are cooked or if one battery is bad? I'll try and calibreate my meters with actual measurments across the batt. terminals. I understand they should charge up to 13.1 ++ but how fast should they discharge to ??. Thanks
I had a bank of Odyssey AGM batteries (400Ah) about two months ago support a 130A load for 40 minutes and they were still at 12.2v, while under the 130A load, at the end of 40 minutes. AGM batteries tend to hold voltage very well if you are dropping voltage under a light load then they are very likely toast.
Re: How low can you go..Discharge prohile for AGMm batterie
Where did you get your odyssey ba?tteries
Where did you get your odyssey ba?tteries
We have a local battery wholesaler but West Coast Battery has some excellent pricing and they have some sweet custom mounts. I would advise against Odyssey UNLESS you have the system to handle them and a stock alternator won't help. Have you considered wets?
Re: How low can you go..Discharge prohile for AGMm batterie
I got away from the wets to grt more AH and avoied the gasing issue. do you think my alternatror is wrecking my agms. I know my charger likes them.
I got away from the wets to grt more AH and avoied the gasing issue. do you think my alternatror is wrecking my agms. I know my charger likes them.
Actually AGM batteries tend to have slightly less Ah per sq in of case than do wets. Optima's are the worst when it comes to Ah capacity because the spiral cells waste a lot of case that could have lead in it. For example the the Optima D31M has only 75Ah's! A group 24 wet cell has 75 Ah's.... The Odyssey PC2150 is basically a group 31 size and has 100Ah, The Lifeline GPL-31 has 105 Ah and the Deka/Duracell/WM Sea Volt group 31 AGM also has 105Ah .....
Contrast those group 31 numbers to the Trojan SCS 225 and US Battery DCXC31 which both have 130 Ah's in a group 31 case.
If you want AGM then the Duracell from Sam's Club is the best value at $166.00 each in a group 31...
AGM & GEL batteries gas just like wets if you over charge them. Problem is they are ruined if you do this where with wets you just add a little distilled water...
AGM batteries more so than wets or GEL like to be recharged to 100% SOC as often as possible. If you let them sit at less than full they will sulfate and give short life. For the price premium you would expect them to easily out last an inexpensive wet but your wet cell is still going and your AGM's were probably dead at year three and you're just stretching it to squeak another year...
If you don't have a battery monitor to know what is going on then I would urge you to invest in one. It will cost less than one AGM battery and could get you 1,2 or 3 more years of service from them if you pay attention....
A 225 Ah bank is not a lot when only usable to 50% of capacity. 50% of 225 Ah's is 112.5 Ah's but when off cruising, and only recharging to about 80% via alternator, then you then drop to 67.5 Ah's of usable capacity before hitting the 50% discharge floor....... 67.5 Ah's can go quickly..
You may be chronically undercharging and over drawing the bank....
Re: How low can you go..Discharge prohile for AGMm batterie
I;m doing to look at a batterybug moniter and hirkland wets or Agm s Thanks for your input!!
I;m doing to look at a batterybug moniter and hirkland wets or Agm s Thanks for your input!!
The Victron BMV-600 is a better product with a lot more features and can be had for $190.00 or less...
Or you could consider a NASA Clipper BM-2 that has a large display showing voltage amperage and battery state all at once... No switching back and forth. It also will monitor voltage on the second bank... Same basic price, but, no messing around with it.
Re: How low can you go..Discharge prohile for AGMm batterie
We have two Lifeline 4D AGM batteries installed under the port settee on our 376 & we use a 160 amp alt from Electromaax to charge the batteries. Never had an issue keeping the batteries charged - you can't charge these batteries properly with a stock alternator.
We also have three 135 watt Kyocera solar panels which will recharge the batteries back to full state of charge everyday while out on the hook.
We have two Lifeline 4D AGM batteries installed under the port settee on our 376 & we use a 160 amp alt from Electromaax to charge the batteries. Never had an issue keeping the batteries charged - you can't charge these batteries properly with a stock alternator.
We also have three 135 watt Kyocera solar panels which will recharge the batteries back to full state of charge everyday while out on the hook.
Agm or Flooded
After comparing prices i' m leaning to wetcell. Either 2 27's or 3 24's. Either will give me 230 or 250 amps respectively. My loads are simple,,no refridge, I havce a honda 2000 generatorand OGM alternator. Gassing on a humid night sets off the CO alarm. What are the pro's and cons here?
After comparing prices i' m leaning to wetcell. Either 2 27's or 3 24's. Either will give me 230 or 250 amps respectively. My loads are simple,,no refridge, I havce a honda 2000 generatorand OGM alternator. Gassing on a humid night sets off the CO alarm. What are the pro's and cons here?
Re: How low can you go..Discharge prohile for AGMm batterie
Actually Jamestown Distributors has BVM600 for $150.
Actually Jamestown Distributors has BVM600 for $150.
Yes I know some of you do not like optimas....To each his own I guess...But in my situation I have a different experence and take on the subject.
I get my optimas from the local auto-zone. They can also handle any replacement or warranty issues if that were to arise. Which for me has been rare. Just once in about 24 years. First set lasted 18 years. When I upgraded up to the new boat I took the 10 year old optimas with me to new boat. One went into my new truck in 2000. It was replaced just before Ike hit. This new battery turned out to be defective with in 10 months. Since I bought it from a local ships store that went out of business I had to go into down town Houston :cussing:to the interstate dealer to handle warranty and replacement. Now I just go to the local auto-zone. The eight I have for my two house banks now have been in use for about 8 years and are still kicking. (Keeping my fingers crossed while Typing.) Just recently I added a new dedicated yellow top for engine start battery, and a dedicated smaller red top battery for generator.
The only Maintenance I do is....
All three banks Live 24/7 while at dock on 12 year old pro-stat 4...30 amp charger. Set for 4 hour absorption...Charger set for wet cell batteries. As per factory recommendations. Despite "I believe" some peoples misinformation to the oposite. Gen starter battery on separate temporary electronic 6 amp charger from Wal-Mart for now. It gets exercised up to about 14.8 volts about every two weeks when gen gets its exercise.
I regularly do same with yanmar. What I do for the house banks though is turn off charger and once a/c has cooled down boat, I wait anywhere from 10 minutes to several hours. Maybe longer depending how long I will be around boat. Then I will kick charger back on. This is in order to trick it into going into rapid max charging. Which I can usually get it to do for anywhere from 30 minutes to an hour before it will then go into 4 hr absorption and then float.
One house bank will run freezer,auto pilot, all electronic instruments,all day long. Sometimes even the inverter and radar part of the day and still start yanmar at end of day. I try never to deplete batteries past 50% although that has happened a few times. At end of day I always make sure they are brought back to a 95 to 100% charge, never leave them at anything less. Once a few months back when freezer was left on battery #two bank, and not shore power. For a unattended three weeks. The ground connection on circuit board of 12 year old pro-stat 4 charger failed and sucked bank #two down two 5.5volts. I repaired circuit board on charger myself. Followed procedures on website video for bringing back a depleted optima. Now everything is back up and running. In fact charger seems to be working better then it ever has.
I am set up so when I am out on the hook or sailing I can start yanmar off any battery I want with out combining batteries. All batteries are isolated from each other. And can be combined and still isolated. I can charge one battery at a time or I can charge starter battery plus one house bank or all house banks off engine alternator. Without combining.
Generator can start on its on battery or I can flip temporary emergency switch which connects to a house bank. Once gen starts it gets shut off. And then gen can take over and run pro-stat 4 charger to charge all banks like charger does while at dock.
Inverter is totally manual (kiss)and only run tv,dvd,microwave and few dedicated house 120v receptacles. Inverter can be used at dock while plugged into shore power or while running on gen or just plain house batteries. All tvs etc. are connected to usp computer back up, when I switch to inverter ups get plugged into the inverter then when at dock it lives on shore power.
Sorry about the long posting but just trying to explain how I have managed to figure out, improve and solve many issuies and problems I have had to over come while getting things working best for me.
I hope this helps others get closer to being able to solving some of there issuies and confusion I have been reading about a lot lately on this forum.
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