Reply
 
Thread Tools Search this Thread Display Modes
 
Old 04-01-2023, 10:53 AM   #21
Senior Member
 
Greg QS's Avatar
 
City: Langhorne
Vessel Name: Quiet Storm
Vessel Model: Nordlund 61
Join Date: Sep 2022
Posts: 309
I have just done all my research on this. I have ordered the batteries. Have special components coming in to make it all work. I should probally start a new thread on it.

life pods are not starting batteries. Most limit current to 200 amp at best. Most starting batteries are 8d like the op are 1005 with two giving you 2005 amps. You cannot draw that kind of power out of lifepods. Starters have super high shock/start draw.

lifepods have a very specific charge profile. You need the appropriate charger.

It is better to have separate start batteries anyway house and start. . This way you have redundancy to start. If the house goes dead you can still start the engine.

lifepods are designed more for the long draw. To power things for long periods, deep discharge, and super fast high amp recharge. Offering High life cycle count. A standard led acid can last for meny years as a starting battery.; but under house conditions they average 3 years or so. Lead acid draw down to 50 % generally gets 500 cycles. 500 / 365 = 1.36 years with daily charge / discharge. Draw them lower than 50% and the count really crashes. The lifepod shine here , even the low end bats claim 3000 cycles at 80%. 3000/365= 8.2 years of daily charge / discharge. Added bonus of no watering. And they protect themselves with the bms tuning them off before damaging them. Normally at the 80% discharge mark.

They both have there place and have there own charge profiles.
Greg QS is offline   Reply With Quote
Old 04-01-2023, 11:06 AM   #22
Senior Member
 
Greg QS's Avatar
 
City: Langhorne
Vessel Name: Quiet Storm
Vessel Model: Nordlund 61
Join Date: Sep 2022
Posts: 309
That article is an interesting read. This is an excerpt. Informative.

DC Motor In-rush


"The reason most drop in batteries cannot be used for starting is the in-rush. The in-rush of large DC motors looks like a dead short to the ( bms) FET’s. Imagine sitting there and intentionally shorting your battery multiple times each day…..That is what starting your motor, running a windlass, electric winch or Bow thruster looks like to the FET’s. There are LFP batteries that can be used for starting but they are very expensive at this point in time."
Greg QS is offline   Reply With Quote
Old 04-01-2023, 12:20 PM   #23
Guru
 
Mambo42's Avatar
 
City: Curacao
Vessel Name: Endless Summer
Vessel Model: 1979 Defever 49
Join Date: Oct 2021
Posts: 665
There are a couple of things you have to take into consideration when you change to LIFEPO4.
1. The charging profile is completely different. AGM will accept lower chargers the closer you get to 'full'.
Lithium on the other hand will keep charging until they are full and when 'Full' happens you need to be carfeful since the alternators or solar are charging at maximum, but when the battteries say "full' you can get a power surge in your system, which can cause a lot of damage. In order to prevent that you should always keep a few AGM batteries on board (e.g. your start batteries) where you excess load will be send once the Lithiums are full.

2. The alternators can charge at max capacity, however doing that for a prolonged period of time could result in overheating your alternators. Better is to have them regulated at roughly 80 % of max capacity. That way they won't overheat.

3. LIFEPO4 is indeed not for starting engines, they are typical house bank batteries, so you will need your standard start batteries.

4. If you want to charge the batteries via generator or shore power you will need to adjust the chargers, they need to go in a different profile.

5. LIFEPO4 can handle a lot of temperatures, but you should avoid charging at freezing temperatures (of the batteries). So if your batteries are in the lazarette and temp drops there below freezing level you will need to add heating plates to the batteries.

6. Normal LIFEPO4 batteries will come with a BMS, but if you happen to buy a battery without BMS you basically need a BMS for every battery. Also need to make sure all the cells are charged separately to the required voltage. If you don't do that the life of the batteries is shortened drastically. Also, make sure never to short the poles of the batteries, that is an instant end of the batteries. You will fry the BMS and sensors, would need to replace them.

There are some more items you need to be aware of, but these are the most important ones. A simple drop in is not going to work, I agree that Youtube has very good videos on LIFEPO4 installation, so can recommend studying them.
Good luck
__________________
If you want sea view...........buy a boat !
Mambo42 is offline   Reply With Quote
Old 04-01-2023, 01:53 PM   #24
Grand Vizier
 
Delfin's Avatar
 
Join Date: Jan 2010
Posts: 3,816
Quote:
Originally Posted by schrater View Post
Oof. Well, further rsearch indicates that LiFePO4 might be fine for house batteries, but will NOT work as my starter battery, due to discharge limits placed by the BMS. I guess I still need AGM for that one. Hope I can mix types on the same charging system.
Those limits are placed because of the battery specs dictated by the manufacturer. Different LFP manufacturers have more robust BMS units, and mine (Lithionics) function just fine as a starter battery. But they aren't $600 for 200 Ah.
__________________
"Dad always thought laughter was the best medicine, which I guess is why several of us died of tuberculosis." - Jack Handey
Delfin is offline   Reply With Quote
Old 04-01-2023, 01:56 PM   #25
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 7,826
Quote:
Originally Posted by Greg QS View Post


lifepods are designed more for the long draw. To power things for long periods, deep discharge, and super fast high amp recharge. Offering High life cycle count. A standard led acid can last for meny years as a starting battery.; but under house conditions they average 3 years or so.

Lead acid draw down to 50 % generally gets 500 cycles. 500 / 365 = 1.36 years with daily charge / discharge. Draw them lower than 50% and the count really crashes. The lifepod shine here , even the low end bats claim 3000 cycles at 80%. 3000/365= 8.2 years of daily charge / discharge. Added bonus of no watering. And they protect themselves with the bms tuning them off before damaging them. Normally at the 80% discharge mark.

They both have there place and have there own charge profiles.
Greg
I agree with most all of what you posted. The one exception I have questioned others about is the " so called" 50% cliff that if you exceed that the cycle life reduces drastically. I have never seen a batty mfgr life cycle charts that reflects what you & others frequently state.
I have done calculations from life cycle charts at various DODs and for FLA & AGM and within a reasonable range... like up to about 70% DOD there is very little loss of total AHs provided by a given batty. The charts show about a 10% rather gradual degradation with higher DODs but nine I've seen show a precipitous drop.
IMO you can't simply compare reduction in # cycles... you need to consider the AHs delivered by those cycles. For instance if a 30% DOD represents one day/ night use and you recharge daily. Now run that same batty for 2 days, to 60% DOD and recharge every otherday it is unreasonable to claim a 50% reduction in life w/:considering the AH delivered. When I ran the #s the total AH delivered were within about 10%+/- for high vs low DOD total AHs delivered over batty life.

Do you gave any life cycle charts that demonstrate what you stated?

BTW... I am not anti LiFePO I just think the marketing literature and most proponents portray an incorrect case for FLA & AGM to justify the benefits of LiFePO.
__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is offline   Reply With Quote
Old 04-01-2023, 03:47 PM   #26
Senior Member
 
Greg QS's Avatar
 
City: Langhorne
Vessel Name: Quiet Storm
Vessel Model: Nordlund 61
Join Date: Sep 2022
Posts: 309
Quote:
Originally Posted by Bacchus View Post
Greg
I agree with most all of what you posted. The one exception I have questioned others about is the " so called" 50% cliff that if you exceed that the cycle life reduces drastically. I have never seen a batty mfgr life cycle charts that reflects what you & others frequently state.
I have done calculations from life cycle charts at various DODs and for FLA & AGM and within a reasonable range... like up to about 70% DOD there is very little loss of total AHs provided by a given batty. The charts show about a 10% rather gradual degradation with higher DODs but nine I've seen show a precipitous drop.
IMO you can't simply compare reduction in # cycles... you need to consider the AHs delivered by those cycles. For instance if a 30% DOD represents one day/ night use and you recharge daily. Now run that same batty for 2 days, to 60% DOD and recharge every otherday it is unreasonable to claim a 50% reduction in life w/:considering the AH delivered. When I ran the #s the total AH delivered were within about 10%+/- for high vs low DOD total AHs delivered over batty life.

Do you gave any life cycle charts that demonstrate what you stated?

BTW... I am not anti LiFePO I just think the marketing literature and most proponents portray an incorrect case for FLA & AGM to justify the benefits of LiFePO.
I have had a boat in registered in my name since 14. 56 as of the 30th. Never gotten more than 3 yars out of a house battery . Even the boat I purchased in 22 , all batteries dead in capacity were from 2018 , 4 YEAEAS old . I cycle too much power through them. Starting up to 10 years. Its how much power you cycle through a led acid. Its simple chemistry. the more power you cycle through the led the more degradation of the led. Resulting in battery failure.

Regardless of Weather or not you accept my documenting. Just look at spec of lead acid. 500 cycles at 50% . lifepods ( my selection ) 7000 cycles at 80%. Simply if the led gets more 2x and the lifepod gest 1/2 your still looking at a cycel of 1000 led verse 3500 lifepod.
Greg QS is offline   Reply With Quote
Old 04-01-2023, 04:01 PM   #27
Senior Member
 
Greg QS's Avatar
 
City: Langhorne
Vessel Name: Quiet Storm
Vessel Model: Nordlund 61
Join Date: Sep 2022
Posts: 309
Quote:
Originally Posted by Mambo42 View Post
There are a couple of things you have to take into consideration when you change to LIFEPO4.
1. The charging profile is completely different. AGM will accept lower chargers the closer you get to 'full'.
Lithium on the other hand will keep charging until they are full and when 'Full' happens you need to be carfeful since the alternators or solar are charging at maximum, but when the battteries say "full' you can get a power surge in your system, which can cause a lot of damage. In order to prevent that you should always keep a few AGM batteries on board (e.g. your start batteries) where you excess load will be send once the Lithiums are full.

2. The alternators can charge at max capacity, however doing that for a prolonged period of time could result in overheating your alternators. Better is to have them regulated at roughly 80 % of max capacity. That way they won't overheat.

3. LIFEPO4 is indeed not for starting engines, they are typical house bank batteries, so you will need your standard start batteries.

4. If you want to charge the batteries via generator or shore power you will need to adjust the chargers, they need to go in a different profile.

5. LIFEPO4 can handle a lot of temperatures, but you should avoid charging at freezing temperatures (of the batteries). So if your batteries are in the lazarette and temp drops there below freezing level you will need to add heating plates to the batteries.

6. Normal LIFEPO4 batteries will come with a BMS, but if you happen to buy a battery without BMS you basically need a BMS for every battery. Also need to make sure all the cells are charged separately to the required voltage. If you don't do that the life of the batteries is shortened drastically. Also, make sure never to short the poles of the batteries, that is an instant end of the batteries. You will fry the BMS and sensors, would need to replace them.

There are some more items you need to be aware of, but these are the most important ones. A simple drop in is not going to work, I agree that Youtube has very good videos on LIFEPO4 installation, so can recommend studying them.
Good luck
All good points . All of this has been addressed . Look at the diagrams.

1 That is the basis of thsis system full communication between batteries and the victron system. It controls the system so the spike you are talinig about cannot happen

2 The wakspeed 500 communicates with the Victron. It has temperature sensors to protect the alternator and will be told to shut down before the batteries shut off. As a secondary note the alternator protect protects from a shutdown.

3 as stated this is house bank only not starting

4 charging is all done through the Victron multiplus as stated is designed and programable for lifepod.

5 These batteries have high and low temp sensors.

6 these batteries each have a bms. They all talk to each other. All readings from each batterie down to the cell are visible on the Victron 7 " display. In the desighn of a rac server system , if a battery drops out, it will not shut down the system , only reduce overall capacity .

These batteries even come with and integral fail safe. Small fire extinguishers in the units as a last line of defiance


This system is not made up . I is designed by Professionals.
Greg QS is offline   Reply With Quote
Old 04-01-2023, 04:05 PM   #28
Senior Member
 
Greg QS's Avatar
 
City: Langhorne
Vessel Name: Quiet Storm
Vessel Model: Nordlund 61
Join Date: Sep 2022
Posts: 309
Quote:
Originally Posted by Delfin View Post
Those limits are placed because of the battery specs dictated by the manufacturer. Different LFP manufacturers have more robust BMS units, and mine (Lithionics) function just fine as a starter battery. But they aren't $600 for 200 Ah.
Again as the design . This is a house bank independent down to the charge sources . All isolated from the Lead acid banks. These are not $600 batteries. Top of the line with all the high end bms , fail safes, even breakers on the batteries. Full communication with the Victron system. The bms's control the system. They are linked to 1 battery that drives the system.
Greg QS is offline   Reply With Quote
Old 04-01-2023, 05:47 PM   #29
Senior Member
 
schrater's Avatar
 
City: Tacoma, WA
Vessel Name: Matilda
Vessel Model: Ponderosa (CHB) 35' Sundeck
Join Date: Sep 2016
Posts: 130
Lots of good advice and perspective here. The one part I’m not following is the assertion that the AGM and LiFePO4 must be on separate chargers due to needing different charging profiles, when other people say it’s fine to use the AGM setting for charging LiFePO4. I wonder if we’re splitting hairs here?
schrater is offline   Reply With Quote
Old 04-01-2023, 07:16 PM   #30
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 7,826
Quote:
Originally Posted by Greg QS View Post
I have had a boat in registered in my name since 14. 56 as of the 30th. Never gotten more than 3 yars out of a house battery . Even the boat I purchased in 22 , all batteries dead in capacity were from 2018 , 4 YEAEAS old . I cycle too much power through them. Starting up to 10 years. Its how much power you cycle through a led acid. Its simple chemistry. the more power you cycle through the led the more degradation of the led. Resulting in battery failure.

Regardless of Weather or not you accept my documenting. Just look at spec of lead acid. 500 cycles at 50% . lifepods ( my selection ) 7000 cycles at 80%. Simply if the led gets more 2x and the lifepod gest 1/2 your still looking at a cycel of 1000 led verse 3500 lifepod.
Greg
I'm not questioning your experience. And certainly not cutting down benefits of LiFePO. My house AGMs are going on 9 yrs. They have been treated well and I try not to leave them extended time at partial charge... I consider FULLY charging adequate about once / wk. Our season is short in NE but I can't charge during 6 mo storage. I have anchored multi days w /o ability to get them fully charged.
In a way, what you say I agree with that LA battys degrade w power consumed (AH consumed). If only going to <50%DOD your point, they should last longer... or mine should die very prematurely.
I have chosen not to consider LiFePO not because I doubt the longevity... I figure I won't be boating or MHing long enough to realize a breakeven... he'll, I may not be alive that long.
Not trying to argue the plusses of Li, only that many exaggerate the performance of LA. I dont believe for a minute that before the Li crowd switched, they replaced batty every 2 yrs... sorry if that's your stand we can agree to disagree.
__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is offline   Reply With Quote
Old 04-01-2023, 08:36 PM   #31
Grand Vizier
 
Delfin's Avatar
 
Join Date: Jan 2010
Posts: 3,816
Quote:
Originally Posted by schrater View Post
Lots of good advice and perspective here. The one part I’m not following is the assertion that the AGM and LiFePO4 must be on separate chargers due to needing different charging profiles, when other people say it’s fine to use the AGM setting for charging LiFePO4. I wonder if we’re splitting hairs here?
Five years into Lithium, the idea that there is a need for separate chargers for my LA starter bank and my LFP bank makes little sense. The manufacturer of my LFP recommends charging to 3.65v per cell - 29.2 @24vdc or 14.6v @ 12vdc with very short to non existent absorption. The net effect of this is that when charging the LA starter bank, the batteries reach a high, but not damaging voltage, then go almost immediately to float. So, hard to see what the point would be for a separate charger. My average lifespan for the LA starter bank is around 8 years.
__________________
"Dad always thought laughter was the best medicine, which I guess is why several of us died of tuberculosis." - Jack Handey
Delfin is offline   Reply With Quote
Old 04-02-2023, 06:41 AM   #32
Guru
 
ranger58sb's Avatar
 
City: Annapolis
Vessel Name: Ranger
Vessel Model: 58' Sedan Bridge
Join Date: Aug 2013
Posts: 7,088
Quote:
Originally Posted by Greg QS View Post
I have had a boat in registered in my name since 14. 56 as of the 30th. Never gotten more than 3 yars out of a house battery . Even the boat I purchased in 22 , all batteries dead in capacity were from 2018 , 4 YEAEAS old . I cycle too much power through them. Starting up to 10 years. Its how much power you cycle through a led acid. Its simple chemistry. the more power you cycle through the led the more degradation of the led. Resulting in battery failure.

Regardless of Weather or not you accept my documenting. Just look at spec of lead acid. 500 cycles at 50% .

We see Lifeline AGMs (lead acid) spec'd at 1000 cycles to 50%. And I think most of the flooded lead acid and AGM 6V "deep cycle" batteries (Trojan, Lifeline, etc.) are spec'd to 1000 cycles... On our previous boat, we got 11 and 12 seasons, respectively, from two different banks of Odyssey AGMs. (Our "cycling" is pretty lightweight, though.)

I wonder if your house banks have been minimally sized? So you've maybe been cycling at 80% or more? Or using starting batteries to service house loads? Or really cheapo batteries? Or...?

Not meaning to sound like I'm questioning your facts, just wondering how you got there from here. Lots of folks seem to get batter results even from crap batteries...

Near as I can tell, the middle-of-the-road lead-acid batteries we're just now replacing lasted probably 5 seasons...

-Chris
__________________
Chesapeake Bay, USA
ranger58sb is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 10:11 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012