How low can you go - battery monitor?

[StratosFearXX]

And still be able to start the thing?

BM6 type battery monitor on starter battery. Not driven for a few days, started fine yesterday but only ran it for 5 minutes while testing something. Seems to read SOC low anyway (I realise it's just making it up from the voltage).

 

[DXX]

Each battery manufacturer / model should have a data sheet online, a lead acid battery shouldn’t be taken below 50% SOC, if it is damage will result.

 

[Anakin]

12.35 V with an AGM battery is over 80% charged, according to this.

Complete Guide: All about AGM Battery Voltage

Complete guide for AGM batteries and learn all the applications for amg batteries.

www.renogy.com

 

[whodat]

My factory AGM battery regularly goes down to 12v. It has started from (to my knowledge) 11.7v before (soon after I got it but 2 main dealers said there was no apparent problem with the battery) . At 11.7v it struggled to start.
The only reason I haven't changed it is that I recently went away for 2 1/2 weeks and the van wasn't started up/driven. When I got back it was sitting at 12v and started on the button - so happy with that.

 

[StratosFearXX]

Thanks 'whodat' good to know.

Wish the battery monitor would give a better idea of true SOC, I've messed with the settings a bit now, and also rejigged my portable solar so I can charge the SB or the leisure battery. Festival next weekend, I have a starter pack if I can't start the engine but also want enough power for several days of electric doors.

 

[whodat]

I give it a topup every so often -
Got an Ecoflow 768 and a Noco 5amp charger. (Not showing off)
Just chuck the Ecoflow in the back and run the cable to the cigarette lighter. Overnight it can use between 0.250KwH-0.5KwH. Just to give a rough idea what size of power pack.
Mine is out of warranty now so if I do need a new battery, will probably try to squeeze in a 95AH S5A13 Bosch which some members on this forum have managed.

 

[Anakin]

I fitted the bigger Bosch battery when mine needed replacing. It is a squeeze, but patience wins out. The Ablemail unit is well worth fitting, as it sits there quietly keeping the SB topped up.

 

[ginkster]

Ignore the SOC, it’s rubbish. Ideally keep it above 12v to avoid damage. It’ll start below that though. Ablemail, Ablemail, Ablemail…..

 

[StratosFearXX]

Ignore the SOC, it’s rubbish. Ideally keep it above 12v to avoid damage. It’ll start below that though. Ablemail, Ablemail, Ablemail…..

I may yet cave and go Ablemail ... would like the SOC in the app to be better, can't understand why it isn't ...

 

[Salty Spuds]

Thanks 'whodat' good to know.

Wish the battery monitor would give a better idea of true SOC, I've messed with the settings a bit now, and also rejigged my portable solar so I can charge the SB or the leisure battery. Festival next weekend, I have a starter pack if I can't start the engine but also want enough power for several days of electric doors.

You should be able to go into the settings and set voltage =SOC% specific you your battery. The factory settings will probably be for a flooded cell battery. Mine is set so that 12.25V=80%SOC

 

[StratosFearXX]

You should be able to go into the settings and set voltage =SOC% specific you your battery. The factory settings will probably be for a flooded cell battery. Mine is set so that 12.25V=80%SOC

Thanks, I'll have another look. I did mess with the settings yesterday which improved things slightly.

 

[CAB]

I think the monitor goes 100-0 at 12.0?

So 43% remaining before the recommended limit, not absolutely flat, if you see what I mean.

12.35v is fine for starting.

 

[StratosFearXX]

I think the monitor goes 100-0 at 12.0?

So 43% remaining before the recommended limit, not absolutely flat, if you see what I mean.

12.35v is fine for starting.

Hmmm, good point.

 

[StratosFearXX]

Well I don't know,, messed with the custom battery settings, didn't make much difference, then set it to 'truck' rather than 'car' and I'm getting a much more sensible SOC reading now. I've got it charging on my solar at the moment though.