battery charge limitation

[Tazzieman]

My typical SoC if in the low 70ties %. Above 70% SoC the charging rate is 1-2 A only. Below 70% SoC - when the numbers are amber - the charging rate is 2 digits, say 10-20 A. Don't remember exactly the threshold for the red numbers (was is 60% SoC?), but then the charging rate goes goes well up above the 50ties A.
I get a SoC above 80% only when using an external battery charger.

Ditto here

 

[Logsplitter]

Edit…
I’m actually a little nervous about taking the batteries out for a maintenance charge due to possible software issues when reconnecting

Don’t take them out. Connect the smart charger to the jump start post terminal under the bonnet as I do.

 

[Karearea]

Don’t take them out. Connect the smart charger to the jump start post terminal under the bonnet as I do.

Thanks, was thinking this would do the trick
So where is the smart charger permanently fixed in yours? Any pics?
And here is the bonus question…
Do you know if there are any of these smart chargers that could be permanently fixed in and also have solar inputs too?

 

[Logsplitter]

Thanks, was thinking this would do the trick
So where is the smart charger permanently fixed in yours? Any pics?
And here is the bonus question…
Do you know if there are any of these smart chargers that could be permanently fixed in and also have solar inputs too?

Not aware of any with solar inputs as all the smart chargers I know of are mains fed.
My charger is currently in the battery compartment but I may move and will definitely reroute mains cable and run through conduit. I’m going to probably fit a camping mains hook up unit with inbuilt rcd and sockets and plug the Victron smart charger into this. When I had the smart charger fitted in South Africa they also fitted mains sockets but they are South African round so figure a ready made mains hook up unit to replace this will be a better option.

 

[Karearea]

Not aware of any with solar inputs as all the smart chargers I know of are mains fed.
My charger is currently in the battery compartment but I may move and will definitely reroute mains cable and run through conduit. I’m going to probably fit a camping mains hook up unit with inbuilt rcd and sockets and plug the Victron smart charger into this. When I had the smart charger fitted in South Africa they also fitted mains sockets but they are South African round so figure a ready made mains hook up unit to replace this will be a better option. View attachment 7862400View attachment 7862402View attachment 7862403

Thanks VERY much for the details @Logsplitter

 

[Skydance]

Single battery. No Smartpass. No high Load Auxiliary Panel. SoC is usually at 99% at the end of modest drives as verified in vehicle settings and in the Offroad panel. Declines about 1% per 24 hour period when not being driven but I haven't been monitoring it much since the battery recovered from its journey to North America and from sitting on the dealer's lot for a month. <1500 miles on the odometer.

EDIT: The vehicle just returned from a 20 mile round trip - mostly highway. SoC 100% while parked and idling (turbo cool down). Voltage 14.3 with engine on.

Just had mine updated and it’s improved much more and similar to what you have just described. You must have one of the newer models.

Basically mine (May 2023) didn't have stop/start from new because the factory forgot the trailer module (I have no tow bar, but it’s still necessary, I believe a few vins are in the same boat as me). Got trailer module fitted last week and it was explained to me
that I have now got the latest software for the module (new).

The stop/start activates quickly and doesn’t cut out too quick and battery charges right upto 100%. I say that’s a result.

So for those who have battery charging issues, there is a new fix coming and I think it’s related between the stop/start and trailer module software.

 

[Karearea]

Just had mine updated and it’s improved much more and similar to what you have just described. You must have one of the newer models.

Basically mine (May 2023) didn't have stop/start from new because the factory forgot the trailer module (I have no tow bar, but it’s still necessary, I believe a few vins are in the same boat as me). Got trailer module fitted last week and it was explained to me
that I have now got the latest software for the module (new).

The stop/start activates quickly and doesn’t cut out too quick and battery charges right upto 100%. I say that’s a result.

So for those who have battery charging issues, there is a new fix coming and I think it’s related between the stop/start and trailer module software.

Thanks @Skydance I will await the update. Mine is a very early vin too but has smartpass and aux battery as it’s a Trialmaster. After six hours driving yesterday I did finally get my onboard SOC up to 78% which was nice to see
However my first start battery monitor “crank test” result at 10.7v after vehicle not run for over a week was slightly worrying
Still, as I’ve said before, Shitake has never let me down so far

 

[255/85]

Just had mine updated and it’s improved much more and similar to what you have just described. You must have one of the newer models.

Yes, purchased in may 2024.

Basically mine (May 2023) didn't have stop/start from new because the factory forgot the trailer module (I have no tow bar, but it’s still necessary, I believe a few vins are in the same boat as me). Got trailer module fitted last week and it was explained to me
that I have now got the latest software for the module (new).

The stop/start activates quickly and doesn’t cut out too quick and battery charges right up to 100%. I say that’s a result.

So for those who have battery charging issues, there is a new fix coming and I think it’s related between the stop/start and trailer module software.

Or it may have simply been a calibration issue as in mislabelling a full charge as <100%. Or vice-versa. Though now I'm thinking that low charge levels were previously confirmed by members here using personal equipment.

I don't think the Stop/Start feature would have a helpful effect on battery condition. Engines primed and at operating temperature do re-start easily but the alternator stops charging when forward progress halts while the lights/HVAC/touchscreen/etc continue to drain power. Traffic jams or long waits at a RR crossing come to mind.

 

[Tomdoc]

Just to add my own experience (dual battery set up with diesel), I have never seen the SoC higher than 85% on the main battery according to the software in the truck. My auxiliary battery charges to 100% as I have a separate "Chinese" battery monitor on it. I am thinking it is just a calibration SW problem but it doesn't bother me at present. Will try a trickle charge to see if I can get the SoC higher that way.

 

[Tazzieman]

Just to add my own experience (dual battery set up with diesel), I have never seen the SoC higher than 85% on the main battery according to the software in the truck. My auxiliary battery charges to 100% as I have a separate "Chinese" battery monitor on it. I am thinking it is just a calibration SW problem but it doesn't bother me at present. Will try a trickle charge to see if I can get the SoC higher that way.

Mine only gets to 82-84% via alternator , 92% on an external charger
Checked with my Topdon battery checker , it confirms these figures.
I don't think 100% is actually achievable whilst driving and using the vehicle.
Except with the auxiliary. That is at 100%.
Monitoring trends is what I do. The system seems quite stable and predictable so I'm happy all is as it should be.

 

[Tomdoc]

Thanks @Tazzieman for confirming my observations. It doesn't really bother me and I have solar charging if needed with the CTEK set up as required.

 

[Jean Mercier]

Mine, from May 2023, petrol, dual battery ...
I saw several times 99% SOC when driving in the mountains. Usually I see around 80%. But sometimes it is really quite low when I don't drive for several days. I don't remember the percentage, but even with 11.80 the car starts without problems.

The percentage is a calculation, based on Voltage and charge, I wouldn't worry too much about it. But I have Chinese battery spies, and I monitor the trend.

 

[LeftCoastOverland]

Mine only gets to 82-84% via alternator , 92% on an external charger
Checked with my Topdon battery checker , it confirms these figures.
I don't think 100% is actually achievable whilst driving and using the vehicle.
Except with the auxiliary. That is at 100%.
Monitoring trends is what I do. The system seems quite stable and predictable so I'm happy all is as it should be.

I’m wondering if ambient temperature has anything to do with it. My truck has also been achieving mid 80’s percentages for SOC down in Cold SW VIC.
However when I first took the vehicle from the agent, it was getting mid 90’s in the warmer QLD climate. I saw the shift as I drove south into cooler temps and it’s stayed that way since.

 

[DenisM]

Mine only gets to 82-84% via alternator , 92% on an external charger
Checked with my Topdon battery checker , it confirms these figures.
I don't think 100% is actually achievable whilst driving and using the vehicle.
Except with the auxiliary. That is at 100%.
Monitoring trends is what I do. The system seems quite stable and predictable so I'm happy all is as it should be.

I recall that very early on there was an article referenced on this forum which had an explanation along the following lines.... the charging profile is designed to charge the main battery using low alternator output, up to say 85% and thus provide a 15% 'surge capacity' to enable the "regenerative" charging to be absorbed efficiently when the smart alternator ups the amperage output under light load/over-run conditions (under braking and/or extended downhill gradients for example)... thus reducing overall alternator drag on engine output....

 

[Tazzieman]

Yes @DenisM I think the boffins knew what they were up to

 

[Clark Kent]

I recall that very early on there was an article referenced on this forum which had an explanation along the following lines.... the charging profile is designed to charge the main battery using low alternator output, up to say 85% and thus provide a 15% 'surge capacity' to enable the "regenerative" charging to be absorbed efficiently when the smart alternator ups the amperage output under light load/over-run conditions (under braking and/or extended downhill gradients for example)... thus reducing overall alternator drag on engine output....

This is the correct answer @DenisM.

@NQ94 posted a pdf article on BMW Intelligent Alternator Control at post #14 of this very thread. Page 7 sums up what's going on. Maintaining the battery at approximately 80% SOC is by design. It's not a fault.
I discussed this with a senior BMW tech recently and he confirmed this is how BMW manage their batteries to reduce fuel consumption and extend battery life. In newer BMWs the target SOC is configurable to allow for the owner's usage pattern. For a city driver the alternator can be set to charge more aggressively during short trips and maintain the battery charge and ensure vehicle operation at the expense of higher fuel consumption.
This intelligent battery management is why we're seeing fluctuations in the charge rates during a drive cycle. Setting aside that there has been some reports of faulty batteries, my suggestion to the forum is to understand this is normal operation so stop fixating on less than 100% battery SOC.

 

[DaveB]

Interesting one yesterday
I hadn't driven the Grenadier for 4 days
When I got in about 10:30 am it started first go as usual, I have the extra Auxiliary battery.
Middle of winter and it had gotten down to 5 degrees overnight, not sure if that had an impact.
Red battery alarm on screen and low battery voltage flashing red
I went to the electrical screen and it showed in red 38% main battery charge.
About 30 minutes of driving battery charge hit 61% and turned amber.
At 71% it turned white and the alarm went off.
It was up to 85 Amps charging for a while. I went down this morning after another 5 degree winters night and showing 65% amber state of charge.
Again kicked over straight away.

 

[Tazzieman]

Interesting one yesterday
I hadn't driven the Grenadier for 4 days
When I got in about 10:30 am it started first go as usual, I have the extra Auxiliary battery.
Middle of winter and it had gotten down to 5 degrees overnight, not sure if that had an impact.
Red battery alarm on screen and low battery voltage flashing red
I went to the electrical screen and it showed in red 38% main battery charge.
About 30 minutes of driving battery charge hit 61% and turned amber.
At 71% it turned white and the alarm went off.
It was up to 85 Amps charging for a while. I went down this morning after another 5 degree winters night and showing 65% amber state of charge.
Again kicked over straight away.

View attachment 7863946View attachment 7863947View attachment 7863948

You need one of those battery testers Dave.

 

[Korg]

Edit…
I’m actually a little nervous about taking the batteries out for a maintenance charge due to possible software issues when reconnecting

Taking them out would be a big undertaking - they are hard to get at and very heavy. Diconnecting them to work on the car is a non-issue in respects to unpsetting the elctrical systems if you first open the drivers door and let the car wake up and then go back to sleep - around 15mins. Disconnect the aux battery negative lead, then the start battery negative lead and then the CTEK connections (if required - make sure that their lights have gone out first). I protect my negative battery leads in plastic zip lock bags while disconnected. To connect back up simply reverse the order. I have done this several times now and have not had any warnings or issues even with the batteries disconnected for several days.

 

[Korg]

Interesting one yesterday
I hadn't driven the Grenadier for 4 days
When I got in about 10:30 am it started first go as usual, I have the extra Auxiliary battery.
Middle of winter and it had gotten down to 5 degrees overnight, not sure if that had an impact.
Red battery alarm on screen and low battery voltage flashing red
I went to the electrical screen and it showed in red 38% main battery charge.
About 30 minutes of driving battery charge hit 61% and turned amber.
At 71% it turned white and the alarm went off.
It was up to 85 Amps charging for a while. I went down this morning after another 5 degree winters night and showing 65% amber state of charge.
Again kicked over straight away.

View attachment 7863946View attachment 7863947View attachment 7863948

You don't have a power hungry Tesla nearby stealing your power overnight?