LiFePO4 Install

[67cj5]

You've nailed it...as I touch on in the thread I posted a couple days ago, the biggest advantage for my situation, is the potential to charge LFP safely, in a hurry, without substantial long term degradation. Someone show me their 80-100AH (useable) FLA system that they can put 50-75AH into in 3- hours of good sunlight during a day, often by noon if I've got all 4 of my 100W panels active.

Yes, it's a bigger initial expense, but I have no doubt that for me, it will be a one-time expense that greatly simplified my power management scheme and in the long run, may end up costing less. And even if it did end up costing more, my time and aggravation is certainly worth something...it's not a system that needs to be pampered or monitored to the nth degree, especially since I've got a fair amount of overhead for my normal usage. I looked hard at staying with FLA, but in the end it just didn't make sense.

Cheers!

The only way to put that much power in to an FLA in 3 hours is to use a charger that's pumping out 20 to 30 Amps in to 2 X 100Ah batteries but the long term damage would be permanent,

Lead Crystal on the other hand would be a cheaper option.

 

[john61ct]

I still think "lead crystal" smells of scam, barely anything worth mentioning, only marketed in a few tiny countries. That discussion worth its own thread though.

There is absolutely no possibility of "damage" from offering "too much current" into a FLA bank, nearly all lead is self-limiting, will not draw more amps than is healthy.

FLA only accepts 0.15-0.2C it is true, so a 400W panel offering say 130Ah/day production in good conditions would be well matched with a 200-300Ah or so bank, smaller if loads are higher in the daytime than at night.

Yes of course high-CAR chemistries will charge faster if high amps are available, but paying 7x (in the NA market) the price up front for LFP is just not worth that for most use cases, looking at it strictly economically, that is a very risky ROI profile.

For some DC power is a hobby, worth paying a lot just to have the new hotness, a racing yacht really needs the weight savings plenty of good reasons to spend the money if you have it.

But FLA at $1/Ah delivered is still pretty compelling for most.

 

[john61ct]

LC threads here, if you want to argue with me resurrect one of these, or start a new one

https://www.google.com/search?q=site:cruisersforum.com+"lead+crystal"

 

[67cj5]

LC threads here, if you want to argue with me resurrect one of these, or start a new one

https://www.google.com/search?q=site:cruisersforum.com+"lead+crystal"

I don't know why I would need to argue with you, there are people here a lot wiser than me when it comes to understanding this stuff,

My way around the High Speed charging Stakes is to run 2 Banks and while one is in use the other is charging, Add a manual switch and switch from one to the other when needed, So why set it up this way ? Easy, the batteries are off the shelf items in any town around the world.

All this high tech stuff is all very well but when it comes to reliability etc just creates even more to go wrong,

Two points always get posted when it comes to people trying to convert others in to believing that Li is the way to go, One is the power that can be drawn off the battery and the other is the weight saving which is not that bigger deal by the time you start adding battery carriers extra Cabling and DC - DC chargers the weight is starting to creep back up.

If someone likes having the Li bragging rights then good for them, But the same applies to folks who like using the older tried and tested Tech from yesterday such as FLA and AGM

Ordinary Starter batteries could be used with good effect because they are designed to deliver huge power in short bursts and charge up quickly soon after and as long as a person has a good Solar setup where the power is always on tap there is no reason why they could not be used if they were not allowed to be drain below their safety point,

LI and LC are not the be all and end all when it comes to batteries they are just another option but one that comes with a rather steep investment and a few mods to get them up and running. and they are by far from perfect as all Tech has it's issues.

 

[john61ct]

My way around the High Speed charging Stakes is to run 2 Banks and while one is in use the other is charging, Add a manual switch and switch from one to the other when needed

That may help with the one goal of getting lead back to 100% Full, but Peukert means you're sacrificing lots of overall capacity that way. In the end, energy input needs to be greater than average outgoing, might as well be drawing and charging from the same bank.

You're also going to higher DoD% every cycle, and that has a **huge** longevity hit.

C-rate on discharge will be much higher for large loads, increasing voltage sag, also stressful.

Finally, given CAR lower than the charge source, wasted energy, charging time is actually slower not faster.

Overall a terrible design for most use cases, hence why it was largely abandoned decades ago, except by some clueless boat maker OEMs.

_____
> Easy, the batteries are off the shelf items in any town around the world

As long as proper deep cycling units like 6V GCs, not mass-market retail 12V automotive stuff with "marine deep cycling" label slapped on it.

Starter batteries should **never** be used for deep cycling usage, absolutely wasting money when good deep cycling units don't even cost more per Ah.

_____
All that aside, we agree on old-school lead being better, more practical and cost-effective for most owners. IMO that means FLA, AGM only where necessary. LC should not even be on the radar.

 

[67cj5]

After my first test using my FLA batteries I have never used more that 10 to 15% because it is impossible to charge them in the time when the sun is at it's peak,


I am trying to work out exactly where Li or LC batteries would fit In to my world, The money side of it is annoying although not the deciding factor, They both have a lot of power on tap and charge fast, I need to run 2 ARB fridge Freezers and a TV that chews between 6 to 8 Watts per hour and a laptop that uses around 31w and about 7w on lighting, Other than that my power requirements are quite small. So which Tech would suit me best is a mystery, I have 3 Smart chargers of various sizes and a couple of normal chargers and when used with a generator I can charge just about any battery on the market, Along with 400w of Solar plus a 100w portable panel. With a 3 or 500w Wind Turbine is next on my Radar.

 

[john61ct]

> I am trying to work out exactly where Li or LC batteries would fit In to my world,

You have no need for anything fancy.

But please stop conflating LFP and LC, nothing to do with each other.

After my first test using my FLA batteries I have never used more that 10 to 15% because it is impossible to charge them in the time when the sun is at it's peak

I do not understand that

 

[67cj5]

But please stop conflating LFP and LC, nothing to do with each other.
I do not understand that

Get off your high Horse, LFP being Lithium and LC being Lead Crystal and they are closer related than you think they both have virtually 80 to 100% power draw capability and they both can be charged at a fast rate, For the Lead Crystal it ranges between 30 and 50% of it's capacity, And they are Half the price of Lithium batteries.

The down side of LC is the weight is on par with FLA and AGM batteries and they are 4 X the price of FLA batteries.

 

[LivinDaDream]

Get off your high Horse, LFP being Lithium and LC being Lead Crystal and they are closer related than you think they both have virtually 80 to 100% power draw capability and they both can be charged at a fast rate, For the Lead Crystal it ranges between 30 and 50% of it's capacity, And they are Half the price of Lithium batteries.

The down side of LC is the weight is on par with FLA and AGM batteries and they are 4 X the price of FLA batteries.

From what little I've been able to glean regarding charge/discharge curves for LC batteries, yeah, you can draw them way down without killing them, but they don't have a mostly flat discharge curve down to the last 10% or less as LFP do. So you can run them down to 0% SOC... what good is the battery for our typical applications when it's output voltage drops below 11V or 10.5V?

As for anyone having bragging rights with LFP, the only thing I can brag about is that I found a solution that works within my limited space and weight confines...and that's a challenge many face. While I have a technical background and like solving problems, ongoing futzing around with my power system is not a hobby for me. I had a problem, I solved it, I'm happy and it didn't break the bank...and if I don't have to touch it for another 5-6 years, it's money well spent.

 

[john61ct]

Nope LC is way overhyped by shady scammers, snake oil IMO.

All six of the top AGM brands in the market can take well over 0.5C charge rate, but only at low SoC and only lasts for 20-30min or so.

Have yet to see any credible evidence of difference from other AGM, not even 0.000001% visibility in any decent sized market.

Firefly Oasis actually do have proven unique properties compared to other AGM, don't see fan boi spamming about them mentioned in the same breath every time with LFP.

 

[67cj5]

From what little I've been able to glean regarding charge/discharge curves for LC batteries, yeah, you can draw them way down without killing them, but they don't have a mostly flat discharge curve down to the last 10% or less as LFP do. So you can run them down to 0% SOC... what good is the battery for our typical applications when it's output voltage drops below 11V or 10.5V?

As for anyone having bragging rights with LFP, the only thing I can brag about is that I found a solution that works within my limited space and weight confines...and that's a challenge many face. While I have a technical background and like solving problems, ongoing futzing around with my power system is not a hobby for me. I had a problem, I solved it, I'm happy and it didn't break the bank...and if I don't have to touch it for another 5-6 years, it's money well spent.

Well the Idea is to keep it fully charged so it has the power you need when you need it so why bother to drain it right down in the first place, A battery that is at a low SOC is no use to anybody no matter if it is an FLA or a LFP, Lithium batteries are not all they can be at the moment but they will be, And hopefully people wise up about the pricing as well.

My last FLA deep cycle battery was 9 years and 8 months old before it died and that was my fault because I didn't drive the vehicle often, the chances are it would still be going now 2 years later if I had not let it go down hill.

 

[dreadlocks]

BattleBorn Update: Brand spanking new battery New Serial Number is ~25k, old Serial Number was ~5k

Installing it now, dont expect any problems.. kinda nice getting fresh new battery w/latest electronics and they didnt refurb my old cells that the BMS might of messed with..

I'm interested in a few things, how much voltage sags w/inverter now.. and how hot the battery terminal gets w/high loads.. I have a feeling both of these conditions will be better than the OG battery.

I leave early Saturday for Grand Canyon.

 

[john61ct]

Good to know they're servicing the warranty well.

And they never learned you were publicly blogging about the experience here?

Return the favour by staying within the limits spec'd, they likely have a logger in there, or that warranty could put them right out of business!

Have a great road trip. . .

 

[dreadlocks]

I never mentioned this post or that any of this was getting publicly blogged, unless they are lurking here.. they have no idea.

Yeah this battery is going to be pampered even harder than the previous one, I never went over their spec'd limits but now I think I'mna use the Victron LFP charging profiles which are far more conservative than how Battleborn's website says how to configure it.

 

[luthj]

My opinion is that you had a bad solder joint on the BMS board from the get go. The excessive heat buildup eventually cascade failed the FETs.