Lifepo4 batteries

[Jim Shanks]

I have a 100 AH Ionic lithium. I was recently at Havasu. In 2 days of using the trolling motor quite a bit It still had 40% charge. It has Bluetooth so you can check the battery charge status on you phone

 

[Littlesaltwash]

I partially switched my rig to Lithium (BattleBorn), last year and couldn't be happier with the performance. I think I'll get one more season out of my other wet cells and then they will be switched to lithium. This is a great website if you are thinking about switching over: Learn About Batteries
@Rivergoer , they don't like that crazy AZ heat, there is a write up on that website about lithium storage in extreme heat / cold.

Thanks, Coho. I went to the mentioned site. There is lots of good info for those of us in the research and learning curve. Here is kind of a summary i what I am learning. Please jump in if any of you know better and I am not accurate or have a misunderstanding. there is lots of new vocabulary and acronyms. Sounds like you should put your boat and batteries away in the fall without charging (unlike wet cells) then charge them back up in the spring before use. very Little draw down over the winter and you don’t want them charging when it is below freezing anyway. Also, IMU, the number of cycles and life of trolling batteries and a house battery should be considerable because of a typical lower discharge ( use with your troller and finders during the day’s fishing) then charged back to a higher level when you crank up the main motor. A single 24v or 36v is less expensive than combining 12’s in a series. But they typically have a lower amp hour rating around the 50-65 mark, whereas lots of 12’s are 100 plus. A drawback to combing multiple batteries in a series configuration could be the communication between the batteries BMS. IMU, one of the reasons lifepo4 aren’t used as a starting cranker is the higher amp draw a motor could require if you have it cranking trying to start for an extended period. Also, in Coho’s mentioned site, they discuss why lithium batteries aren’t used a starters in cars and trucks because of the sustained amperage from the alternator. Suppose the same could be true for the newer outboards with their alternators? Will is mainly a solar guy but seems very knowledgeable. Does anyone know of a specific marine lifepo4 site with information?

kThe will prowse site has the SOK and also recommends Battleborn. He is upfront though and mentions he does get compensation. Battleborn are assembled in the USA of imported components resulting in a higher price. Other brands shipped from China reflect the lower labor wage. I haven’t discovered any of the lifepo4 batteries completely made in America. Jim, a 100. 24volt?.

 

[Littlesaltwash]

I was able to talk pretty extensively with some Lifepo4 techs last week and have a better understanding of the big picture with lifepo4 batteries. They are not a plug and play system. Those who just go out and buy a lifepo4 and drop it into their system have a good chance of failure, not only in ruining the high dollar battery but their electrical system in their motor. So, instead of one line info bites this post has the possibility of matching JFCCalifornia for length. (I appreciate his detail). My boat has an AGM starter (recommended by Mercury for the higher CCA.) and a wet cell deep cycle house battery for all the lights, gauges, finders, etc. on the boat. Because the boat has two batteries to be charged, it has a battery isolater. There is a wire from The motor’s alternator into the isolator and then a leg to the cranker and a leg to the house battery to keep them charged Or charge at the same time. Current thru a battery isolator only goes oneway. current from your batteries will not go back into your alternator. Important. lifepo4 batteries are not recommended or suitable to be used as starter batteries at this stage in development (I know there are some who use them or some manufactures who have “dual purpose”) Read: If lifepo4 batteries were ok for starting/charging/recharging They would be in all of our cars and trucks And that is what we would be using instead of regular lead acid bats. IMU they do not like being under the constant amp charge after being fully charged unlike a traditional lead acid. So in my situation I would keep my AGM starter. I could then put in a lifepo4 for the house battery. But, I cannot hook that up to the isolater like wet cell to charge because of that dislike. I would need a DC to DC, 12v/12v, charger to charge my 12 volt lifepo4 battery, whatever the rated amp hour I would get. This charger is wired to the AGM and goes to the house. I am Assuming that the charge thru that charger can also only go one way. The charger recommended was the Victron IP67. Several lf4 suppliers recommend this particular charger also. Victron plays heavily with lots of different electrical parts in the electric world. At this point, I can start my motor safely with the recommended battery and cold cranking amps and have and charge a lifepo4 battery to run all the 12 volt stuff on my boat, finders, live wells, lights, and if lucky, a filet knife!

For the trolling motor system: If I were to change out the batteries in the trolling motor system I would go with a 24 volt battery. A 24 volt lifepo4 has one BMS, battery management system. This keeps the 8 cells balanced and monitored. (A typical 12 volt has 4 cells). There are those folks out there who series 12 volt batteries together to get their 24 or 36 but there can be an issue with that. Now instead of one BMS in a 24 volt battery or a 36, you have 2 or 3 BMS in your set up. IMU a BMS in one battery does not communicate with the other bms in the others. This is why ecobatt last year recommended a one battery trolling system (as do the geeks I am talking to). Those of you who have 12 volts wired in a series probably remember they were advised to charge their lifepo4 batteries to 100% before hooking them up. The reason was given to me with this analogy. Suppose you have two glasses of water (24v), one is half full and the other is completely full. if you turn on your troller and start draining the “water” one of those glasses goes to zero while the other is still at 50%. Now you only have 12volts left in one battery and the other battery and it’s BMS is being asked to do something it can’t do. System doesn’t work and possible damage to battery #2???? IMU you can do the series thing but it can be more difficult/expensive to be safer than sorry. To charge my 24 trolling battery I would need a DC to DC charger, 12/24, 12 volt to 24 volt. This is also connected to the starter, AGM battery, and has wires gauged correctly for the distance to the front of the boat. My geeks told me the chargers didn’t come with the transfer wires because they could be traveling 8 inches or 20 feet and the gauge requirement would be different in order not to lose juice. So far, i keep the AGM starter. I have a lifepo4 for the house that can be recharged by my motor thru the AGM safely. And I have a trolling motor system that can also be charged thru the AGM . each battery needs or should have a monitoring system That you can monitor either on your dash or Bluetooth, or both. You can then keep track of what is going on with your batteries (discharge, amount of charge left, etc. lots of lifepo4 dealers recommended the victron BMV 712, Bluetooth model, or the BMV 702, same thing but not Bluetooth. kind of to summarize what I have found out is that yes I can switch over to lifepo4 batteries but I need other components to do it right the first time. There are lots of options with the other components that allow faster recharge/monitoring/etc but they all require more money too.
This was a long winded post but I know there was at least one other wording that was interested in the lifepo4 topic. There is more info out there such as lifepo4 batteries can be rebuilt or components replaced/ you can build your own battery system/ the batteries can last for years and years/ charging parameters/etc. For those interested in switching over to lifepo4, do your own research for your particular situation. The system is not cheap to do it right.

 

[TR.]

I was able to talk pretty extensively with some Lifepo4 techs last week and have a better understanding of the big picture with lifepo4 batteries. They are not a plug and play system. Those who just go out and buy a lifepo4 and drop it into their system have a good chance of failure, not only in ruining the high dollar battery but their electrical system in their motor. So, instead of one line info bites this post has the possibility of matching JFCCalifornia for length. (I appreciate his detail). My boat has an AGM starter (recommended by Mercury for the higher CCA.) and a wet cell deep cycle house battery for all the lights, gauges, finders, etc. on the boat. Because the boat has two batteries to be charged, it has a battery isolater. There is a wire from The motor’s alternator into the isolator and then a leg to the cranker and a leg to the house battery to keep them charged Or charge at the same time. Current thru a battery isolator only goes oneway. current from your batteries will not go back into your alternator. Important. lifepo4 batteries are not recommended or suitable to be used as starter batteries at this stage in development (I know there are some who use them or some manufactures who have “dual purpose”) Read: If lifepo4 batteries were ok for starting/charging/recharging They would be in all of our cars and trucks And that is what we would be using instead of regular lead acid bats. IMU they do not like being under the constant amp charge after being fully charged unlike a traditional lead acid. So in my situation I would keep my AGM starter. I could then put in a lifepo4 for the house battery. But, I cannot hook that up to the isolater like wet cell to charge because of that dislike. I would need a DC to DC, 12v/12v, charger to charge my 12 volt lifepo4 battery, whatever the rated amp hour I would get. This charger is wired to the AGM and goes to the house. I am Assuming that the charge thru that charger can also only go one way. The charger recommended was the Victron IP67. Several lf4 suppliers recommend this particular charger also. Victron plays heavily with lots of different electrical parts in the electric world. At this point, I can start my motor safely with the recommended battery and cold cranking amps and have and charge a lifepo4 battery to run all the 12 volt stuff on my boat, finders, live wells, lights, and if lucky, a filet knife!

For the trolling motor system: If I were to change out the batteries in the trolling motor system I would go with a 24 volt battery. A 24 volt lifepo4 has one BMS, battery management system. This keeps the 8 cells balanced and monitored. (A typical 12 volt has 4 cells). There are those folks out there who series 12 volt batteries together to get their 24 or 36 but there can be an issue with that. Now instead of one BMS in a 24 volt battery or a 36, you have 2 or 3 BMS in your set up. IMU a BMS in one battery does not communicate with the other bms in the others. This is why ecobatt last year recommended a one battery trolling system (as do the geeks I am talking to). Those of you who have 12 volts wired in a series probably remember they were advised to charge their lifepo4 batteries to 100% before hooking them up. The reason was given to me with this analogy. Suppose you have two glasses of water (24v), one is half full and the other is completely full. if you turn on your troller and start draining the “water” one of those glasses goes to zero while the other is still at 50%. Now you only have 12volts left in one battery and the other battery and it’s BMS is being asked to do something it can’t do. System doesn’t work and possible damage to battery #2???? IMU you can do the series thing but it can be more difficult/expensive to be safer than sorry. To charge my 24 trolling battery I would need a DC to DC charger, 12/24, 12 volt to 24 volt. This is also connected to the starter, AGM battery, and has wires gauged correctly for the distance to the front of the boat. My geeks told me the chargers didn’t come with the transfer wires because they could be traveling 8 inches or 20 feet and the gauge requirement would be different in order not to lose juice. So far, i keep the AGM starter. I have a lifepo4 for the house that can be recharged by my motor thru the AGM safely. And I have a trolling motor system that can also be charged thru the AGM . each battery needs or should have a monitoring system That you can monitor either on your dash or Bluetooth, or both. You can then keep track of what is going on with your batteries (discharge, amount of charge left, etc. lots of lifepo4 dealers recommended the victron BMV 712, Bluetooth model, or the BMV 702, same thing but not Bluetooth. kind of to summarize what I have found out is that yes I can switch over to lifepo4 batteries but I need other components to do it right the first time. There are lots of options with the other components that allow faster recharge/monitoring/etc but they all require more money too.
This was a long winded post but I know there was at least one other wording that was interested in the lifepo4 topic. There is more info out there such as lifepo4 batteries can be rebuilt or components replaced/ you can build your own battery system/ the batteries can last for years and years/ charging parameters/etc. For those interested in switching over to lifepo4, do your own research for your particular situation. The system is not cheap to do it right.

Well said. I went through all of this as well and it can be mind numbing. I kept my AGM for a starter as well. The only thing I would add is that the alternator doesn’t get the backlash from say the BMS shutting down however the sudden drop to nothing to charge surges the alternator or rectifier and can fry the parts of the motor instantly. I *think* the victron dc to dc has a plan for that. I agree Victron is the way to go but you sure do pay for it. There is also a surge protector you can add from Victron that absorbs the power surge of a BMS shutdown and I think it goes between the battery and the motor. After monitoring my new setup a bit now it appears that a full day of fishing drains 40 of my 200 amps. Of the 200 amps my charger only tops off at about 90% capacity and my BMS keeps 10% at shutoff. That means I have about I have about 160 amps available…all 100% like an agm just came off the charger. this means I should be able to fish 4 days before a recharge, so I decided to not go through the expense and potential issues of a dc to dc. Your results may vary

TR