Battery charging

[DenisM]

Hesitated where to post this, there are several possible other threads where I could post it, and didn't want to start a new thread. This is meant as a reference for other users.

My car (Trialmaster, double battery and SmartPass) wasn't used during 5,5 days.
The voltage of the main battery dropped from 12.9 Volts tot 12.7 Volts.
When putting the contact on, the battery status (State Of Charge) of the Grenadier showed 85% and the voltage dropped to 12.3 Volts (all kinds of systems are draining some current).
The State Of Charge (SOC) of my cheap Chinese monitoring system is calculated in a different way and says 98% at 12.2 Volts.
See the next pictures, the first two coming from the Chinese battery monitoring system:
View attachment 7835631
View attachment 7835632
View attachment 7835633

Quite happy with the behavior of my battery. (No "non-Grenadier" current consuming devices connected while "not driving", apart from the Chinese monitor).

Hi @Jean Mercier ...Going by other references for Lead Acid batteries, 12.19V is interpreted as somewhere between 35% -42% SOC. The indicated 98% on this basis seems a tad "optimistic"...

 

[bemax]

My battery still can’t decide whether it wants to be empty or nearly full after a week without driving.
As far as I can imagine I have nothing switched on that could possibly draw the power.

 

[Tazzieman]

My battery still can’t decide whether it wants to be empty or nearly full after a week without driving.
As far as I can imagine I have nothing switched on that could possibly draw the power.

There is a small hole in the base from which electrons are escaping at night whilst you are asleep.

 

[DenisM]

My battery still can’t decide whether it wants to be empty or nearly full after a week without driving.
As far as I can imagine I have nothing switched on that could possibly draw the power.

There's "parasitic" power draw from the alarm system and the wireless remote which is "waiting waiting / on alert" for the key fob to unlock the doors...they are interconnected obviously. Also, the Ctek Smartpass draws power continuously checking the relative SOC of each battery...

 

[holdmybeer]

There's "parasitic" power draw from the alarm system and the wireless remote which is "waiting waiting / on alert" for the key fob to unlock the doors...they are interconnected obviously.

This theory seems unlikely, no? Factory fobs and alarms have been mainstream for 20 years. I have only experienced a handful of makes and models but the power draw of a vehicle parked with remote and alarm system listening has never been an issue over a week. Or more.

 

[Solmanic]

Since my recent battery woes in this thread, I now have negligible power draw from the new battery when the vehicle is left unused for a few days. The new battery loses maybe 1% per day when idle, and routinely now charges to 98-100%. Just to recap, my original battery state of charge would plummet if anything was drawing power when the vehicle was off. A DPF regen after 2hrs driving was the final straw and crashed the battery from 79% to zero. I subsequently confirmed the failure by running a small cooler for 1/2 hour and that was enough to send the state of charge from 80% to zero. Now with the new battery it is clear that the old one was dodgy right from delivery and if I hadn't had the total collapse I might have just kept on assuming that was just how things were meant to be.

 

[das mo]

Same here

Was there a solution for this proven solid?
+ is easy. Not sure about a solid fix point for the -.

 

[Eric]

There is a small hole in the base from which electrons are escaping at night whilst you are asleep.

I have electrons breaking into my battery at night. Parked up after a 63 mile journey yesterday, SOC showing 77% (Ah I thought smart alternator trying to keep it at 80%). Went to the vehicle this morning to go to town, and immediately before I cranked the engine SOC 90% . Finished shopping, parked up at SOC 91%.
Conclusion - Intelligent Battery System data transfer to head unit is at best a guesstimate or crap

 

[das mo]

I have electrons breaking into my battery at night. Parked up after a 63 mile journey yesterday, SOC showing 77% (Ah I thought smart alternator trying to keep it at 80%). Went to the vehicle this morning to go to town, and immediately before I cranked the engine SOC 90% . Finished shopping, parked up at SOC 91%.
Conclusion - Intelligent Battery System data transfer to head unit is at best a guesstimate or crap

That is simply chemistry working after your ride before arriving in a balanced state few hours after driving.

 

[Tazzieman]

I have electrons breaking into my battery at night. Parked up after a 63 mile journey yesterday, SOC showing 77% (Ah I thought smart alternator trying to keep it at 80%). Went to the vehicle this morning to go to town, and immediately before I cranked the engine SOC 90% . Finished shopping, parked up at SOC 91%.
Conclusion - Intelligent Battery System data transfer to head unit is at best a guesstimate or crap

No, you just have the wireless charging pad installed.
With the Chineses tracking software....

 

[Cheshire cat]

I like @DCPU idea, charge, with a smart charger through the live pin on the 13 socket. I'm going to make one up while waiting.

My version of an idea from DCPU in which I can use my Optimate battery tenders. I saw similar on a caravan thread from someone with 7000 contributions over the years. Although calling himself Griff. Something about it was very DCPU.

 

[Survivor]

Hello, small question to the electric experts. Is it possible to hook up a charger or on of those folding solar panels with Pwm controller on a aux outlet at the roof? Of course with the battery switch turned on. I’m looking for a easy solution to support the battery while I’m camping and the fridge is running.

 

[Cheshire cat]

Hello, small question to the electric experts. Is it possible to hook up a charger or on of those folding solar panels with Pwm controller on a aux outlet at the roof? Of course with the battery switch turned on. I’m looking for an easy solution to support the battery while I’m camping and the fridge is running.

I have done so using the tow hitch socket

 

[Survivor]

I’ve seen this option, but I would like it more to use the outlets on the roof cause I like to put the solar panel on the roof while using it and in this case the cable could be much shorter.

But thanks for pointing out the hitch socket option. This is my plan B