LFP Info

[BFL13]

Much info here for RVers too not just boaters, covering many of the things discussed on this forum.

Eg warnings about BMS amp rating vs battery AH size, charging--beware of charger absorption time duration, what about |"floating", using GEL setting, and much else of interest to DIY and drop -in buyers. It is very long so suggest saving it to read in parts in slow time.

https://marinehowto.com/lifepo4-batteries-on-boats/

[3_tons]

pianotuna wrote:
Perry,

The only reason to charge to 100% with Li is to "reset" the battery management system and "balance" the cells. Once a month appears to have several votes.

Every thirty days to 100% is what is recommended for SiO2, but for entirely different reasons.

I would also add here, to allow for shunt meter re-synchronization…The ‘once a month’ to 100% idea is not a driving factor - the number of less than full charge cycles is…

Multiple up and down charge cycles of say less than a full 100% can over-time result in small amounts of cumulative meter drift…Meter re-synchronizations AND periodic cell-balancing present the need for an occasional re-charge to 100% SOC, followed thereafter by a brief holding period to accommodate cell re-balancing…

When camping (after such…) my preference is to aid battery longevity by then shutting-off ALL charging (this, to refrain from holding the battery at 100% SOC)…Thereafter, harvest is used to stay within a workable up and down range of somewhere between 10-90% SOC…JMO

3 tons

[StirCrazy]

pianotuna wrote:
Perry,

The only reason to charge to 100% with Li is to "reset" the battery management system and "balance" the cells. Once a month appears to have several votes.

thats only if you have active balancing as part of the BMS. but its true more and more are coming out with it now. for me the reason to charge to 100% is so you have 100% of your capacity available if you need it. there no issue for repeatadly charging to 100% whie you out camping if your using the battery. just don't charge it completly before storage most people say. so for myself I would just turn off my charge controler at like 70%

I myself do not understand the reason for that. through a bunch of reading all people say is because the self discharge is lower, so...... I would like to see some actual real info on what happens to the battery if you do. granted I have never specificly looked for that so it may me easy to find, but niether have I seen the real reasons in any post.

[pianotuna]

Perry,

The only reason to charge to 100% with Li is to "reset" the battery management system and "balance" the cells. Once a month appears to have several votes.

Every thirty days to 100% is what is recommended for SiO2, but for entirely different reasons.

[PerryB67]

I'm about two-thirds through the article and despite the last edit in 2017 I have seen what is stated many times over the last couple of years. Hell, Renogy and Battleborn can't agree on charging, much less others. For example, do you charge to 100% frequently/daily or just a couple times a week? Not expecting an answer.

Enjoy,

Perry

[StirCrazy]

pianotuna wrote:
I didn't realize RVnet was about debating. I thought we were here to share real life information, and offer help to others. I stand corrected.

we are, but sharing outdated misleading info that are spun because of sales pitches isnt real life information. and there has been plenty of that in the past. my opinion is you can share info but be prepared for some one to question that information, thats how any real deicent paper that has creditable backing is verified, its called peer review.

so I post something and maybe there is a little section that is outdated or not quite right, some one brings this up and we have a discussion about it so everyone can learn, we don't go crying butt hurt and hide because some one called us out or had the gall to question what I typed.

plus its winter and you know what winter is like here... no camping not much posting so more debates haha..

Steve

[pianotuna]

I didn't realize RVnet was about debating. I thought we were here to share real life information, and offer help to others. I stand corrected.

[Itinerant1]

That article has been updated a couple times over the years by the author.

BFL13, I posted a link to a different article in this thread (LFP vs. Lead Acid) when you were confused so you could understand more of what you were debating thoughout the thread back in April of 2021. Lots of good info there.

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/30225474/srt/pa/pging/1/page/1.cfm

😉

[StirCrazy]

BFL13 wrote:
Much info here for RVers too not just boaters, covering many of the things discussed on this forum.

Eg warnings about BMS amp rating vs battery AH size, charging--beware of charger absorption time duration, what about |"floating", using GEL setting, and much else of interest to DIY and drop -in buyers. It is very long so suggest saving it to read in parts in slow time.

https://marinehowto.com/lifepo4-batteries-on-boats/

you can tell this is a very old article, I have to finish reading it but have to go back to bed, working nights. but on his DIY stance 13 years ago when he built his (and the cells he used look from about that erra) you had to do all the sizing and such your self. so the BMS used to be a kit you have to solder the componants on unless you wanted to drop big bucks to get one to do it, then you had to program the settings on them.. well now in 2022, that stuff is all done for you, which take diy to a level that anyone who can set up parralel series batery systems can assemble one. even the matching of cells and such he is talking about is done for you when you buy from a reputable company and there are a few now from china and more starting to pop up in canada and the USA but just because there a north american company doesnt mean there good. I know a few people who have bought out of the US and got b grade instead of the A grade they paid for, so there are scammers everywhere, do your reasearch.

plus the next paragrap he states he prefers drop in batteries, expecialy the ones he sells because he beleaves they are the best.. why would you make DIY sound good if you sell a premade solution.

I wish we could get well written articles that didn't have a alterior comercial side to them....

[pianotuna]

BFL13,

Nice Find.