flashing battery symbol

[pjstock]

though I do have a question of course...

this morning the battery symbol on the display is flashing.
which normally indicates a Too Low Battery Charge (which the manual seems to suggest is under 10.5v)

but the house battery charge is looking pretty good I thought - 12.3v

or. is that too low?

we'll be driving today somit will charge
and we plan to replace the batteries with LiFePos

[pjstock]

although strange, after I briefly started the engine this morning, and then turned it off, the display indicator dropped quickly to 10.7v > 10.5v > 10.2v.....

before climbing again to 11.x and 12.3v

[pi-high]

Hi,

Good luck on your trip. Unless I am mistaken, that panel you are showing only shows the state of the house batteries. Even with my 12 year old AGM batteries, my reading is usually around 13.7 volts when driving or parked in the sun with 200 watts solar. Unless you are ready for installing a DC to DC connection, I have read that you might risk an alternator meltdown with a new Life Po system. Or maybe not. We are soon heading the opposite direction from Victoria to Ontario. My backup plan for a battery failure is to drop in a couple of group 31 AGMs from Canadian Tire. Heck, in another 12 years I will be over 90, so that should last me. Cheers ... Harvey

[pjstock]

it's weird.
last night the compressor in the fridge was making a terrible racket - it sounded like a cat was dying in there.
at that time (2am) the display ready 12.2v
thinking it might be a depleted battery (and damaging the compressor system) I turned the fridge off.

this morning we drove only a short distance - maybe 4kms -
and I turned the fridge ON before parking and going for a day trip

at that time it read 12.8v
when we returned it read 11.8v but the fridge was still running and was not squealing.

we then drove a short distance home and parked

the display currently shows 12.4v, the fridge is running correctly and quietly..

we'll see what it does overnight.

but Yes I plan to install a DC DC charger to allow me to charge to LiGePos off the alternstor

[komposti]

Schöne Grüße über den Teich,
das vertsehe ich jetzt nicht: Warum sollte man LiFePo Akkus NICHT über den Generator (Lichtmaschine) laden können

Das sollte doch Plug and Play funktionieren ...

Hallo nach Victoria auf Vancouver Island

Thomas

[pjstock]

I got this info from this video (from a boat guy, but the same principles apply to camper vans like ours. and there there are hundreds of videos on this topic)

https://youtu.be/jCZfa2r-QMY?si=WnSghMkrWG9XMDbj

1. LiFePos have BMS which will shut the battery down / Off under certain conditions

2. LiFePos have much lower resistance than Lead Acid batteries so they can absorb a lot of power very quickly. .Lead batteries charge the last 20% very slowly, in small power increments.

3. an alternator is a power producing device W (= VxA). it pushes Watts to the LiFePo using Volts

4. if the BMS turns the battery OFF (so it stops accepting more power) the alternator will continue trying to push Watts but since it cannot the Voltage will skyrocket (to infinity?)

5. once the V passes 100V DC that destroys the diodes in the alternator . and the alternator will not work until those diodes are replaced.

6. worse in the instant the diodes are being destroyed the entire power system of the boat or RV is exposed to 100+v DC.

Summary: old alternator + LiFePo batteries = bad mix.
LiFePos will disconnect when full, alternator will keep trying to push power, Voltage will soar, alternator will be destroyed , and equipment could be ruined by high DC voltage.

peter

[komposti]

Kann bitte jemand aus der Elektroniker Gilde im Forum hierzu Stellung nehmen
Ich bin da mit meinem laienhaften, gefährlichen Halbwissen überfragt.

Es haben doch schon viele Kollegen auf LiFePo umgerüstet.

Bin gespannt auf Eure Post´s denn bei mir steht es ja auch an.

BG Thomas

[woodz]

Servus pjstock,

da das hier eine Frage zu (einer) scheinbar schwachen Bleibatterie(n) ist, möchte ich folgendes beisteuern:

Das Symbol blinkt bei einem niedrigsten Spannungswert und hört erst wieder auf bei einem Mindest-Spannungswert (Motor starten, Solarladen oder Netzladen) -> Hysterese. Die genauen Spannungswerte können vermutlich aus der Bedienungsanleitung entnommen werden.

Vom Gefühl her würde ich keine el. Geräte mehr betreiben, wenn Die Spannung der Batterie(n) regelmäßig unter den niedrigsten Wert fällt. Ausgenommen die Wasserpumpe, denn dort steckt keine Elektronik dahinter.

Die Batterie(n) baldmöglichst zu tauschen, ist sicher eine gute Sache, denn sie sind bereits tiefentladen.

Grüße woodz

[pjstock]

excellent advice