jkidd
Active member
New testing results for FLA, AGM and Li
https://www.youtube.com/watch?v=iy3hga_P5YY
https://www.youtube.com/watch?v=iy3hga_P5YY
More Battery Testing I dare you to watch the whole thing.
- Thread starter jkidd
- Start date
colbysmith
Active member
Didn't have time to watch it yet. But give me the bottom line. Am I a fool for just sticking with my three old style marine12vt deep cycle and starting batteries in my boat? :roll: Colby
colbysmith
Active member
Thanks. I'll have to take a gander at that video later! Colby
Jody,
Thank you for the link to the most interesting video. The main take away was of course that by his "standards" it was cheaper to have a LI than AGM, and a little cheaper than a Flooded Lead Acid (FLA) battery.
Aside from the cold part--which would rarely affect most of us in our C Dorys. He emphasized use of Watt Hours, vs Amp hours. He is absolutely correct.
The Li battery starts at about 13.4 to 13.6 volts, and remains above 12 volts until 90% discharged:
Below from Solacity web site:
If you look at the AGM or FLA battery the resting voltage is 12.6 to 12.8 and "50%" discharge is usually considered at 12.2 volts...If you take much more out of the battery, you begin to deteriorate the batteries longevity. Now in his tests he did take both AGM and FLA to 9 volts, and mentioned that they "recovered". It was not entirely clear that he was making the distinction between a battery under load at 12.2 volts, or a battery at resting state (that is no charge or discharge for at least 2 hours). The 12.2 volts being 50% discharged for a FLA is dependent on the that battery being at rest.
They used a setup almost identical to what I am using in my C Dory 25; That is two BattleBorn 100 amp hour batteries in parallel, to a Victron Multiplus 2000/80/50. This is a 2000 watt PSW inverter with an 80 amp charger. They changed the charging profile with the computer--it can be done with the computer (more flexibility) or with dip switches on the circuit board of the charger. Once set for LIFePO4-=in real use, you leave it there. The remote for the inverter can also set limits of power used for charging, if running off a generator.
I agree with Jody that a Bat to Bat charger is certainly the best way to charge the LiFePO4 battery. However, there are a lot of boaters who are just using the outboard charger--they never get the full amount of power available, and run some risk of damage. The internal Battery Management System (BMS) should prevent any over voltage damage. Many RV's are just using a timing device, with a automatic charging relay, where they let the alternator charge for a period of time (15 minutes, and the rest for 30 minutes to avoid over charging). For example my RV has a 200 amp alternator continuous duty rated, vs the 44 amp alternator of the Honda 150 and 17 amp alternator of the pre 2007 Honda 90.
As I was designing my system I was not "thinking" watt hours, but I was thinking about having the voltage above 12 volts until the last 10%--and I would never use that last 10%. I have my cut off voltage set at 12 volts on the inverter.
Also I feel that one has to have a commitment to using the boat either frequently off grid, wanting to own the boat for a long time, or just wanting to experiment. For the average C Dory owner, I am not sure that the LI battery is worth the cost. In our case, we run a microwave and induction burner for cooking--plus have chest freezer and refrigerator, so there is a constant 24 hour a day low amp draw of the chest freezer/refer, and the short term high amp draw of the microwave and induction burner. Thus we have the need for needing high capacity batteries. IF you just have a Wallas stove, or heater and LED lights, there is probably little need for the Li battery. We are also seeing the Li used frequency in boats which use trolling motors. A 36 volt 110# thrust trolling motor will run many hours on a 36 volt 50 amp battery bank. There is a huge weight savings, and the fishermen will have far more capacity--or use time.
The average FLA lasts 3 or so years. The LiFePO4 battery should last over 12 years, depending on use.
Thank you for the link to the most interesting video. The main take away was of course that by his "standards" it was cheaper to have a LI than AGM, and a little cheaper than a Flooded Lead Acid (FLA) battery.
Aside from the cold part--which would rarely affect most of us in our C Dorys. He emphasized use of Watt Hours, vs Amp hours. He is absolutely correct.
The Li battery starts at about 13.4 to 13.6 volts, and remains above 12 volts until 90% discharged:
Below from Solacity web site:
If you look at the AGM or FLA battery the resting voltage is 12.6 to 12.8 and "50%" discharge is usually considered at 12.2 volts...If you take much more out of the battery, you begin to deteriorate the batteries longevity. Now in his tests he did take both AGM and FLA to 9 volts, and mentioned that they "recovered". It was not entirely clear that he was making the distinction between a battery under load at 12.2 volts, or a battery at resting state (that is no charge or discharge for at least 2 hours). The 12.2 volts being 50% discharged for a FLA is dependent on the that battery being at rest.
They used a setup almost identical to what I am using in my C Dory 25; That is two BattleBorn 100 amp hour batteries in parallel, to a Victron Multiplus 2000/80/50. This is a 2000 watt PSW inverter with an 80 amp charger. They changed the charging profile with the computer--it can be done with the computer (more flexibility) or with dip switches on the circuit board of the charger. Once set for LIFePO4-=in real use, you leave it there. The remote for the inverter can also set limits of power used for charging, if running off a generator.
I agree with Jody that a Bat to Bat charger is certainly the best way to charge the LiFePO4 battery. However, there are a lot of boaters who are just using the outboard charger--they never get the full amount of power available, and run some risk of damage. The internal Battery Management System (BMS) should prevent any over voltage damage. Many RV's are just using a timing device, with a automatic charging relay, where they let the alternator charge for a period of time (15 minutes, and the rest for 30 minutes to avoid over charging). For example my RV has a 200 amp alternator continuous duty rated, vs the 44 amp alternator of the Honda 150 and 17 amp alternator of the pre 2007 Honda 90.
As I was designing my system I was not "thinking" watt hours, but I was thinking about having the voltage above 12 volts until the last 10%--and I would never use that last 10%. I have my cut off voltage set at 12 volts on the inverter.
Also I feel that one has to have a commitment to using the boat either frequently off grid, wanting to own the boat for a long time, or just wanting to experiment. For the average C Dory owner, I am not sure that the LI battery is worth the cost. In our case, we run a microwave and induction burner for cooking--plus have chest freezer and refrigerator, so there is a constant 24 hour a day low amp draw of the chest freezer/refer, and the short term high amp draw of the microwave and induction burner. Thus we have the need for needing high capacity batteries. IF you just have a Wallas stove, or heater and LED lights, there is probably little need for the Li battery. We are also seeing the Li used frequency in boats which use trolling motors. A 36 volt 110# thrust trolling motor will run many hours on a 36 volt 50 amp battery bank. There is a huge weight savings, and the fishermen will have far more capacity--or use time.
The average FLA lasts 3 or so years. The LiFePO4 battery should last over 12 years, depending on use.
Interesting ending. I knew the Li batteries would pay off in the long term use, (like 2 or 3 battery changes) but I was surprised to see the difference between the AGM and FLA's at the cost per watt.
I still think the bulk of the weight and size of the 12V to 12V charger and the rest of the set up for the Li's out weighs the advantage on a 22.
Harvey
SleepyC :moon
I still think the bulk of the weight and size of the 12V to 12V charger and the rest of the set up for the Li's out weighs the advantage on a 22.
Harvey
SleepyC :moon
Harvey, the battery to battery charger is fairly small--Perhaps you are looking at the inverters that they are using in the video. I see the cost of the whole system as more of an issue. Plus that these are not suitable for starting. Some of the other manufactures claim theirs are OK for starting outboards.....
The dimensions are (h x w x d): 5.1" x 7.3" x 3.2" and weight is 3#. If this had been available, I would have used it, rather than the Sterling, but they are both the same size.
Yes, not so much just the 12 to 12, but the whole system, and it all needs to be "not in the weather" which meant inside, under the galley. Pretty much all full there already.
Here's another good source for info on the Li batteries.
https://www.pysystems.ca/
I spent quite a bit of time with Jeff, when I was thinking of going with the Li Ion batteries, (not Battle Born but...). I just decided that it wasn't going to work for me . . . yet.
Harvey
SleepyC :moon
Here's another good source for info on the Li batteries.
https://www.pysystems.ca/
I spent quite a bit of time with Jeff, when I was thinking of going with the Li Ion batteries, (not Battle Born but...). I just decided that it wasn't going to work for me . . . yet.
Harvey
SleepyC :moon
colbysmith
Active member
That would be the deal breaker right there for me. I still think for my use and setup, the tried and true lead acid marine battery suffices. Cost, weight, efficiency, etc. Since I now run one group 24 marine starting battery for it's intended purpose, which works well, and two group 29 marine deep cycle batteries, I've had no problem running the boat's refrigerator, our Engle freezer, a cpap, anchor light and heater for 8-12 hours over night, and still wake up with 70% showing on the battery monitor. Oh, and also running a small fan overnight and reading for about an hour at night with the lights on. We do have all LED's in the lighting. Colby
hardee":9yayo3sc said:
Indeed we all have to make our our decision. The link nor do any of his other videos appear to deal with the major issue which the link that Jodi posted. That per unit of power (watts) the Li battery had more, and was actually more cost effective, despite the price.
Beside the battery the cost is that of the DC to DC charger, which is in the $260 range, and I got a 10 amp LI battery charger on Amazon for about $100. It also measures voltage and amps in, during its phases. I use this for maintenance or low use charging off $100.
As I noted for most of the C Dorys it is not cost effective...
To address Colby's issues. "Group " size battery only refers to case size. There can be different amp hours or reserve capacity in these. The group 29 is a rare bird, and many manufactures don't list it. The usual amp hours is somewhere between 100 and 110 on a average--but as we saw in the video Jody posted, that FLA or AGM don't really have as much capacity as they claim...The ambient temps make a great deal of difference when dealing with freezers and ref. Generally both of these run in the 4 to 5 amps per hour, 60 amp hours over 24 hours per unit would not be unusual. X2 120 amp hours. Lets say you want to stay for 3 days in one place, and no solar--that would mean either running the motor some prolonged time, or a generator and a high capacity battery charger, to keep the generator run time down. At Powell, we found that 2 to 3 hours of 30 amp charging a day was necessary for our one chest unit. My charger allowed dialing in a charging amount . Even then we were not fully charging the battery. Even 100 watts of solar panel was not adequate. 200 watts of solar panel is what seems to be required to keep one of the. chest type units running.
jkidd
Active member
I have the LI battery installed for the house in the port lazarette and the dc to dc charger in the same space. I wanted to keep the wires as short as possible. So far these are the advantage’s that I am seeing.
Battery weighs 29 lbs the AGM battery weighs 78 lbs for a savings of 49 lbs.
If there were 2 house batteries I would save 120 lbs for the same capacity.
I can now use nearly 100 percent of the rated capacity instead the 50 percent of lead acid.
The LI battery does not need to be charged back up to 100 percent within 24 hours like lead acid.
The LI battery likes to be kept between 30 to 90 percent with no ill effects.
I can run multiple days without charging and use the capacity of the battery if I like.
I can disable the dc to dc charger if the LI battery doesn’t need charging.
Don’t have to worry about over charging the house battery when batteries are combined.
The LI battery life is 3000 to 5000 cycles 4 to5 times the life of lead acid.
I will be doing the same charge test that I did with the AGM house battery to see the results.
While this is pricey up front over time it will pay for itself might not have to buy another house battery for 15 years or more and if I buy a new boat I can move that battery to the new one.
Battery weighs 29 lbs the AGM battery weighs 78 lbs for a savings of 49 lbs.
If there were 2 house batteries I would save 120 lbs for the same capacity.
I can now use nearly 100 percent of the rated capacity instead the 50 percent of lead acid.
The LI battery does not need to be charged back up to 100 percent within 24 hours like lead acid.
The LI battery likes to be kept between 30 to 90 percent with no ill effects.
I can run multiple days without charging and use the capacity of the battery if I like.
I can disable the dc to dc charger if the LI battery doesn’t need charging.
Don’t have to worry about over charging the house battery when batteries are combined.
The LI battery life is 3000 to 5000 cycles 4 to5 times the life of lead acid.
I will be doing the same charge test that I did with the AGM house battery to see the results.
While this is pricey up front over time it will pay for itself might not have to buy another house battery for 15 years or more and if I buy a new boat I can move that battery to the new one.
T.R. Bauer
New member
No question Li batteries are better and the video just reaffirms what others have shown as well. But, in actual usage, it is amazing how long commercial grade lead acid batteries will last that are made to be discharged over and over again. I got 11 years on NAPA 6V golf cart batteries in my motorhome before replacement, and I wasn't exactly easy on them in the usage department. But, they never were allowed to get corroded up, had water, always were charged, never over charged, and occasionally equalized/desulphated. I was also pretty careful about how far I let them go down, but never crazy about it and there were times they were below 50% after a long cold night with the furnace constantly coming on. I have boat buddies running 8D batts for about the same length of time - even longer. The point is, you can get a good value out of them with care. I really don't like how heavy the 8D batteries are! But, they are in boats where a heavy battery does not matter one bit. I get sticker shock looking at the Li batteries.
The niche use for LiFePO4 batteries is where Light weight is important, many charge discharge cycles is important, where more power is important, where you can turn the battery in any position, including upside down, is important, where rapid charge, and discharge is important, where you can cycle betteen 30% and 90% of charge is important. where voltage is maintained until the last 10% of capacity is important. Where you do't or cannot check electrolyte level.
I have on occasion gotten 10 years out of batteries. However this is not the rule for most boaters. I don't advocate them for all boaters, and in our case it is more of an experiment in new technology rather than a necessity....but it is also nice to be able to run the refer/freezers for several days, without recharging if necessary, as well to have plenty of power to. run the microwave and induction burner, Yet be able to pump 40 amps back into each battery in a relative short period of time.
The cost is not that far off if you are buying either premium FLA or AGM batteries.
I have on occasion gotten 10 years out of batteries. However this is not the rule for most boaters. I don't advocate them for all boaters, and in our case it is more of an experiment in new technology rather than a necessity....but it is also nice to be able to run the refer/freezers for several days, without recharging if necessary, as well to have plenty of power to. run the microwave and induction burner, Yet be able to pump 40 amps back into each battery in a relative short period of time.
The cost is not that far off if you are buying either premium FLA or AGM batteries.
Next boat when it comes to replacement of house bank - for sure. After doing research I just love these batteries. Being able to use nearly 100% of what you have with very little drop off and damage of the battery is a huge plus. Just better batteries when you look at the whole pictures. Thanks for sharing.