Equalizing batteries
- Thread starter NYSail
- Start date
I never equalize with loads on my batteries, but I don't know that you can't. I also isolate and equalize each battery separately, but that is likely because of the limitations I have in my equalization method. Since I have two batteries, I run the house off the battery I'm not equalizing.
Basically, I don't know the answer to your question - only relating what I do...
dj
p.s. - Do you have temperature sensing of your battery? You really should...
Basically, I don't know the answer to your question - only relating what I do...
dj
p.s. - Do you have temperature sensing of your battery? You really should...
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NY,
Here's a link that may answer some of your questions for both wet cell & AGM batteries.
Hope this is helpful.........
http://lifelinebatteries.com/2015/10/can-i-equalize-agm-batteries/
Here's a link that may answer some of your questions for both wet cell & AGM batteries.
Hope this is helpful.........
http://lifelinebatteries.com/2015/10/can-i-equalize-agm-batteries/
The simple answer is maybe. Some devices that you run may be sensitive to over-voltages. You'll be equalizing at 15+ VDC. e.g., While the compressor motor on your refrigeration probably wouldn't mind that, you may have electronic control boards that have components that might get damaged.
We have equalized occasionally in the past with our Lifeline batteries with the refrigeration on. I checked with SeaFrost (the manufacturer of our DC system, they said that "should be fine". It was.) One proviso: make sure you really don't go vay over the VDC that you're supposed to be charging at "a bunch". I wouldn't run our B&G instruments, even though they say they can take that over voltage, because I'm just a wimp; and, I'd avoid the radar being run.
On reason to avoid running systems: The equalization is based on WHAT IS ACTUALLY GETTING TO THE BATTERY TERMINALS. If you have a refrigeration running, you may be actually seeing lower voltage than you need at the battery terminals. Measure what's really being "seen" at the terminals. Our Mastervolt system and controls allows us to manually adjust the voltage so we can adjust it. Some other chargers don't do that.
I know a number of marine electricians who have recommended using an adjustable "standalone" charger. They actually monitor what's going on. I'd advise you not to simple engage the "equalization cycle" on your inverter, and then leave the boat on the expectation that nothing goes astray.
Are you just going to use your inverter on "equalize"? Make sure the battery bank is charged-up BEFORE you run the equalize function. You don't want to cooking the batteries (or you charger) by having it pumping a lot of amps into the bank. I believe you want to just bring the voltage up to equalize level without a lot of actual amperage being pumped in.
We are replacing our Lifelines with LiPro's because I had it with their tendency to sulfate. I'd tried everything to maintain them with a "religious" attention to not-discharging them with bringing them up to "full charge", equalizations every month or two, careful attention to temps of the batteries, and monitoring voltage at battery terminals during charging, etc., etc.
First set of Lifelines (on our current boat) from 19 years ago lasted 7 years. I mistakenly replaced them because "they owed us nothing" and out of an abundance of caution. Next coupe sets, lasted three or four years. Then two sets over less than a couple of years each before their effective capacity became intolerable for 4- 4D's.
We have Lithium Ion - Relions being installed this month. https://relionbattery.com/products/lithium/application/marine.
We have a MasterVolt charging system.
We have equalized occasionally in the past with our Lifeline batteries with the refrigeration on. I checked with SeaFrost (the manufacturer of our DC system, they said that "should be fine". It was.) One proviso: make sure you really don't go vay over the VDC that you're supposed to be charging at "a bunch". I wouldn't run our B&G instruments, even though they say they can take that over voltage, because I'm just a wimp; and, I'd avoid the radar being run.
On reason to avoid running systems: The equalization is based on WHAT IS ACTUALLY GETTING TO THE BATTERY TERMINALS. If you have a refrigeration running, you may be actually seeing lower voltage than you need at the battery terminals. Measure what's really being "seen" at the terminals. Our Mastervolt system and controls allows us to manually adjust the voltage so we can adjust it. Some other chargers don't do that.
I know a number of marine electricians who have recommended using an adjustable "standalone" charger. They actually monitor what's going on. I'd advise you not to simple engage the "equalization cycle" on your inverter, and then leave the boat on the expectation that nothing goes astray.
Are you just going to use your inverter on "equalize"? Make sure the battery bank is charged-up BEFORE you run the equalize function. You don't want to cooking the batteries (or you charger) by having it pumping a lot of amps into the bank. I believe you want to just bring the voltage up to equalize level without a lot of actual amperage being pumped in.
We are replacing our Lifelines with LiPro's because I had it with their tendency to sulfate. I'd tried everything to maintain them with a "religious" attention to not-discharging them with bringing them up to "full charge", equalizations every month or two, careful attention to temps of the batteries, and monitoring voltage at battery terminals during charging, etc., etc.
First set of Lifelines (on our current boat) from 19 years ago lasted 7 years. I mistakenly replaced them because "they owed us nothing" and out of an abundance of caution. Next coupe sets, lasted three or four years. Then two sets over less than a couple of years each before their effective capacity became intolerable for 4- 4D's.
We have Lithium Ion - Relions being installed this month. https://relionbattery.com/products/lithium/application/marine.
We have a MasterVolt charging system.
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I equalize my bank 2 or 3 times a year but I always isolate the loads. The Freedom 2000 charger cautions that in equalizing mode the voltage gets up to 15 or 15.5 volts and to be sure the loads can handle that voltage. Out of an abundance of caution I prefer to isolate the loads for the 8 hour equalizing cycle.
@SG I'm currious about your decision. Looking at the link you provided for LiFePO4 batteries I'm surprised at the capacity. I thought they would have more capacity than a similar sized lead acid battery but they appear to be about the same, some even less. They are lighter, so maybe it is just the capacity to weight ratio that is better. Was it just the life span that drove you to lithium? My experience with lithium rechargeable batteries has only been in portable electronics and they don't tend to last more than a few years, although they are not generally treated very well. Discharging to 20% state of charge you get less than 500 cycles, somewhat more if you go to 50% discharge. I suppose that is more than 5 years for a boat used mostly on weekends. - Sorry for the thread drift 
On the original topic, I'd disconnect the battery from the load when equalizing. Some equipment can be sensitive to overvoltage causing irreparable (or expensive) damage.
On the original topic, I'd disconnect the battery from the load when equalizing. Some equipment can be sensitive to overvoltage causing irreparable (or expensive) damage.
I run the boat off the reserve bank when equalizing the house bank. If the fridge is working, I just turn it off for those few hours and plan ahead around it to minimize the # of times I open it. It stays cold and can be a good day to defrost it anyway.
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Many (me too) do not have a charger that will equalize. How about a recommendation for a stand alone equalizer - a 110 v unit like a 15 v power supply maybe?
Charles
Charles
I'm currious about your decision. Looking at the link you provided for LiFePO4 batteries I'm surprised at the capacity. I thought they would have more capacity than a similar sized lead acid battery but they appear to be about the same, some even less.
I have 4 - 4D's Lifeline AGM's with in the order of a "face" rating of 800 AH (not counting the engine and generator start batteries). However, I almost never used more than 400 AH out of the bank by design because I didn't want to lessen their life; and, it just takes too long to recharge them using our Balmar "rated" 250 Amp alternator (which doesn't put anywhere near that much out in the real world" and our 200 AH MasterVolt (which really puts out about 135 Amps in the real world, before the house loads take their share).
The Lithium batteries can be discharged heavily with no impact; and, I didn't i) have the room under the floorboards where my AGM's reside; or ii) really want to spend the extra money. I think that having over 500 AH of real capacity to drain down is more than enough.
I'm sensitive to the notion of being careful with our charging -- the MasterVolt Combi has those capabilities. When were in offshore mode through shipping lanes we use an ungodly amount of power (PC, Two displays for the Furuno Chart Plotter/Radar, Two NorthStar chart plotters with Sirius weather, Class B AIS, refrigeration, B&G H5000 with a lot of displays, charging various portable devices, etc.
I have 4 - 4D's Lifeline AGM's with in the order of a "face" rating of 800 AH (not counting the engine and generator start batteries). However, I almost never used more than 400 AH out of the bank by design because I didn't want to lessen their life; and, it just takes too long to recharge them using our Balmar "rated" 250 Amp alternator (which doesn't put anywhere near that much out in the real world" and our 200 AH MasterVolt (which really puts out about 135 Amps in the real world, before the house loads take their share).
The Lithium batteries can be discharged heavily with no impact; and, I didn't i) have the room under the floorboards where my AGM's reside; or ii) really want to spend the extra money. I think that having over 500 AH of real capacity to drain down is more than enough.
I'm sensitive to the notion of being careful with our charging -- the MasterVolt Combi has those capabilities. When were in offshore mode through shipping lanes we use an ungodly amount of power (PC, Two displays for the Furuno Chart Plotter/Radar, Two NorthStar chart plotters with Sirius weather, Class B AIS, refrigeration, B&G H5000 with a lot of displays, charging various portable devices, etc.
I have equalized my Lifelines multiple times without problems, but I turn off the 12 volt breakers of many un-needed items like the watermaker - why take the risk?
But like SG, I’m giving up on Lifelines and going to Fireflys. My current Lifelines are barely four years old but showing a 40% loss in capacity. I don’t think they’ll make it to five years which I expect of a premium battery. As with SG, I’ve followed all of the care guildelines including the equalization. Equalization, in particular, is a pain in the neck. It takes 8 hours and you are supposed to monitor the batteries the whole time. It pretty much steals an entire day when I could be sailing. They suggest you do it as often as monthly.
But like SG, I’m giving up on Lifelines and going to Fireflys. My current Lifelines are barely four years old but showing a 40% loss in capacity. I don’t think they’ll make it to five years which I expect of a premium battery. As with SG, I’ve followed all of the care guildelines including the equalization. Equalization, in particular, is a pain in the neck. It takes 8 hours and you are supposed to monitor the batteries the whole time. It pretty much steals an entire day when I could be sailing. They suggest you do it as often as monthly.
I'm honestly just blown away at the short life-times you are all talking about on your lead-acid batteries. I frankly don't understand it. Many years ago, one of the electrical engineers from the Hoover Dam taught me about how to maintain flooded lead acid batteries - expected life-time definitely over 10 years. It's so many years ago now, that I honestly don't recall what he told me is the expected lifespan, but 15 years seems about right for what he told me back then. But I'm sure he gave me more info around that. But in any case, I've followed his instructions as best I can ever since then and can tell you that I rarely get under about 12 years of useful life from my lead acid flooded batteries. There is the occasional battery that fails due to mechanical failures, but I buy cheap batteries...
I've actually just had one really cheap flooded lead acid battery die on me after 12 years of service, but I can truly say it is my fault as I discharged the battery to close to 0% charge and then didn't get my arse in gear to perform a complete equalization on that battery for close to a month. When I finally got to doing it, it didn't really work. I wasn't surprised and although I was able to salvage it and run it almost a year after that. It is now officially dead...
Equalization is a pain. No question about it. I will also tell you, 8 hours is typically quite short for getting a full equalization done. I typically spend somewhere between 12 and 36 hours (depending upon how neglectful I've been) in performing an equalization step. I also typically don't do it with my batteries in the boat. I take the battery that I'm equalizing out of the boat and bring it home and do it here in my house. I typically get between 12 and 18 years out of a flooded lead acid battery. At this point, I don't live on my boat, so for anyone that lives on their boat, I really don't have any answers on how to do this... But for the rest of the folk that can either connect to shore power, or could take their batteries out and bring them home, I just don't understand these short battery lives reported. Just to put this in perspective, I've been doing this for close to 35 years both on land and on the water...
dj
I've actually just had one really cheap flooded lead acid battery die on me after 12 years of service, but I can truly say it is my fault as I discharged the battery to close to 0% charge and then didn't get my arse in gear to perform a complete equalization on that battery for close to a month. When I finally got to doing it, it didn't really work. I wasn't surprised and although I was able to salvage it and run it almost a year after that. It is now officially dead...
Equalization is a pain. No question about it. I will also tell you, 8 hours is typically quite short for getting a full equalization done. I typically spend somewhere between 12 and 36 hours (depending upon how neglectful I've been) in performing an equalization step. I also typically don't do it with my batteries in the boat. I take the battery that I'm equalizing out of the boat and bring it home and do it here in my house. I typically get between 12 and 18 years out of a flooded lead acid battery. At this point, I don't live on my boat, so for anyone that lives on their boat, I really don't have any answers on how to do this... But for the rest of the folk that can either connect to shore power, or could take their batteries out and bring them home, I just don't understand these short battery lives reported. Just to put this in perspective, I've been doing this for close to 35 years both on land and on the water...
dj