How to look after Lifepo4 without looking at the BMV 712

[Fuss]

I had a procedure with my old lead that I ended up not looking at gauges and they were self managing.... sort of...

It went something like this...
have a real easy system for watering them
have some solar to maintain them full when off the boat
some of the solar to contribute to the daily charging
give them a 32v equalise every 3rd month when in port
size the alternators for 30 mins avg charging per day to keep them full. That means that when I ran the motor they sometimes charged at more than 150ah.


When I bought the boat the batteries were charged with a 70ah alternator that quickly dropped to 10ah so I think the batteries were a bit damaged when I bought it.


I damaged them more in the end before buying Lifepo4, but they lasted 16 years in total.


So how would this work with Lifepo4?
Would it be something like this...
Make sure you know as much as possible about Lifepo4 and do your best to install and configure everything correctly.
Continually monitor and check and modify until all is working in the right way.
Ensure all alarm and charging configurations are correct.
Know their personality, like how often do they need an active balance

Then follow some guidelines for your sailing style...


Would the guidelines be something like this...

Leave them around 50% SOC when off the boat.
Calculate how much energy you use in different circumstances
size the alternators to easily put this energy back in the shortest period of time without exceeding the manufacturers charge C rating.
Have a method of switching off the charging systems.
Don't bother charging them full.

[Pete7]

Why are you giving them a 32v equalising charge? What voltage is the battery system.

Pete

[Fuss]

It’s 24v , is my post along the right lines?

[sailorboy1]

I made the change to LFP a few months ago. If you stay away from the people looking to make some type of "perfect" system it is easy.

-Install the batteries
-Change your various charging system setpoints based on the LFP
-Ensure your alternator isn't going to run max output for hours on end
-protect the alternator from overheat
-have a "dump" source (like a regular lead acid start battery) in line for the alternator in case you screwed up the setting and they disconnect
- go on your happy way

I bet most larger boats with 400ah+ have the needed equipment already except maybe the alternator temp sensor. I made no physical change to my boat.