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If you are only concerned with your car battery and not other batteries which are not in the car, it makes far more sense to buy a diagnostic tool that can be used for many things in order to extract SoC readings from the BMS. The BMS will be calibrated to your exact battery and it will have the benefit of constantly analyzing it when it provides its output. That tool can also do many other things, amortizing your investment, while a dedicated battery health device can only look at batteries, and if the battery is in the car, it will not provide good SoC data because the device can not know what is or is not connected to the battery.
 
Yeah, I could use my Launch to search for the battery status, but I doubt it would give useful information in case the BMS has a problem, i.e. not charging the battery properly. As said before, I trust my (cheap) digital battery analyzer (and my DVMs) and they tell me the battery is OK, but weakly charged - this is my issue. So my big Q is, do I have a BMS problem, or do all Macans behave like mine, which then would eventually require much more battery care, even a daily one (e.g. when continuously charged below 50% by the BMS)?
 
Yeah, I could use my Launch to search for the battery status, but I doubt it would give useful information in case the BMS has a problem, i.e. not charging the battery properly. As said before, I trust my (cheap) digital battery analyzer (and my DVMs) and they tell me the battery is OK, but weakly charged - this is my issue. So my big Q is, do I have a BMS problem, or do all Macans behave like mine, which then would eventually require much more battery care, even a daily one (e.g. when continuously charged below 50% by the BMS)?
While I do not nesecessarily agree with you, it would at least be interesting to see what SoC the Launch reports from the BMS.
 
Discussion starter · #884 ·
Do not trust the BMS. They go bad. Always go directly to the source.

Trust the battery analzer directly on the terminals.
 
When I replaced my 2016 Macan battery, November 2022 with a Clarios made, Pep Boys Champion AGM 900 CCA/95AH…
Before installation I bench tested it. Multi meter showed only 12.48 V! I suspect it has been sitting on their shelf for many months. The date sticker was 5/22 and I suspect they had not charged it since then. I had to charge 15–18 hours before CTEK showed that it was done!

After it was fully charged per CTEK and still before I installed it, I checked again with the multi meter and got a reading of 13.45 V! (Yes, I realize that some of this was surface charge)
I then tested with my solar capacitance tester.
Solar 13.34 V, OK (? CCA), SOH = 100%, SOC = 100% 2.54 mΩ
{I forgot to write down the CCA but must have been 900 CCA or more to yield SOH 100%}


When I replaced my 2019 911 C2S battery with Clarios made Walmart Everstart 900 CCA/95Ah (Walmart.com mail to home N/C shipping) did not have a date stamp but bench tests:
Out of the box multi meter = 12.69 V
Charge with CTEK 4.25 hrs till done.
MM=13.28 V.
Wait 2 hrs. b4 test with Solar to dissipate surface charge.
1:40 AM 50˚F in garage
Solar= 13.01 V 100%
SSA/CCA 900
942 CCA, “OK”
SOH = 100%, (I calculate 942/900 = 105%)
SOC = 100%, 2.67 mΩ

Bottom line, I think AGM batteries, when fully charged, have 13+ V… Unlike flooded lead acid batteries which have less.
2.1 v/cell, T= 12.6 V
some charts show 2.12 v/cell, T= 12.7 V
here are 2 charts FLA & AGM
Image



Image
 
Is there a way to know the "health" of the battery? Like how one can view the battery of a Macbook's laptop battery. I'm assuming it's not the SoC.

If, say mine after being ignore for a few yrs (gotten used) of being not in a battery tender and below the required use per year, can that be somewhat reversed back to better health by the CTEK's recon stage as it charges?
 
SoH, is a measure of the battery's ability to deliver a quantity of watt-hours as a percentage of a new battery's capability. Over time, degradation of the battery by various means (sulfation, breakdown of plates and acid solution etc.) causes the battery's output capability to decrease.
can be seen:
- using a stand alone battery health checker like this which typically uses battery internal resistance as a way to estimate battery SoH
  • using a diagnostic tool to pull that info out of the Macan's BMS which monitors this parameter constantly and should be a better measure of SoH
  • other more sophisticated methods which measure the battery's charge capacity through discharge testing or tracking the amount of charging necessary to achieve a target SoC

I have read that AGM batteries do not respond well to attempts to recover lost SoH using a maintainer in reconditioning modes. However, using a standalone tester and the CTEK MXS 5.0's AGM RECOND setting, I was able to see a modest increase (a few % if I rccall correctly) in SoH on a 7 1/2 year old Macan battery I keep around as an emergency power source.
 
So in short, negligible. ....but the CTEK runs a recon on its own every single charge ass part of the 8-stage, does it not?
 
Solar BA9 by Clore Automotive is ~ $50.
This will be an inexpensive way for you to measure state of health for any battery. (S.O.H)
State of health is measured as a percentage of the measured CCA/spec CCA.

So if your battery measures 110 CCA and the specification is 900 CCA… SOH = 90%.


I think Clore is a USA company, unlike many Automotive tools, which are made by Chinese companies.


I bought mine from Amazon but, not the third-party seller JB tools.
 
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The more I read up on chargers, the more I don't want to use this Noco 10A charger of mine....especially on the regular lead acid with lower capacity. Yuasa EFB even recommends around 3-6A for charging. Ignorance is bliss.
 
So in short, negligible. ....but the CTEK runs a recon on its own every single charge ass part of the 8-stage, does it not?
Not sure about every CTEK model but the MXS 5.0 has a recondition mode which needs to be selected.

Image
 
Discussion starter · #892 ·
Ctek Reconditioning does work on flooded batteries. It gave me about another year on my Cayman battery.

Ctek Reconditioning does NOTHING on AGM batteries, direct from ctek support




Reconding an AGM battery … does not help … , so we cannot recommend recond program on AGM batteries ….

Do NOT trust the BMS, they go bad and give false readings, trust the BA on the battery terminals

Do not take voltage readings from the jump points, they will be false

Do not trust the internet charts on AGM SOC. Trust your BA

Do not use CCA common for American cars, use DIN on the battery for SOH

YMMV
 
Ctek Reconditioning does work on flooded batteries. It gave me about another year on my Cayman battery.

Ctek Reconditioning does NOTHING on AGM batteries, direct from ctek support




Reconding an AGM battery … does not help … , so we cannot recommend recond program on AGM batteries ….

Do NOT trust the BMS, they go bad and give false readings, trust the BA on the battery terminals

Do not take voltage readings from the jump points, they will be false

Do not trust the internet charts on AGM SOC. Trust your BA

Do not use CCA common for American cars, use DIN on the battery for SOH

YMMV
That's a little odd about the reconditioning of AGM batteries with the CTEK MXS 5.0 since the MXS has a specific AGM - Recondition program (in addition to a specific recondition program for non-AGM) and the FAQ / Support page for the MXS does not mention not reconditioning AGM's.

FAQ - NA - MUS4.3, MXS5.0 & variants (ctek.com)
 
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Discussion starter · #894 ·
That's a little odd about the reconditioning of AGM batteries with the CTEK MXS 5.0 since the MXS has a specific AGM - Recondition program (in addition to a specific recondition program for non-AGM) and the FAQ / Support page for the MXS does not mention not reconditioning AGM's.

FAQ - NA - MUS4.3, MXS5.0 & variants (ctek.com)
yes, and that is the exact same question others have brought up, see


If I remember right, I also called CTEK support and they said it did nothing


Direct from CTEK Support

"Recond program is developed only for flooded batteries (including EFB), to remix the flooded acid inside. The remixing/balancing is necessary to treat an already stratified battery, or to prevent severe stratification. AGM or GEL batteries are not flooded, and therefore does not suffer from stratification. That means Recond will not help AGM or GEL."

Its also in the Honda Forum, Land rover, etc and its a stock answer from CTEK


Recondition definitely DID, help my dying Cayman battery that was flooded, got about another year of life out of it.
 
According to that diagram of CTEK’s stages, 1 is Desulphation at 15.8v but I thought AGM’s charging should be max of 14.8v, to which the CTEK charges at 14.7v.
 
15.8V is just the voltage limit the CTEK outputs. In case of the weakest imaginable battery, no car electronics should be harmed. In case the battery is in better state, the CTEK "hammers" on the battery with 5amp spikes, to literally get rid of the sulphur crust without letting the voltage rise above 15.8V.
 
15.8V is just the voltage limit the CTEK outputs. In case of the weakest imaginable battery, no car electronics should be harmed. In case the battery is in better state, the CTEK "hammers" on the battery with 5amp spikes, to literally get rid of the sulphur crust without letting the voltage rise above 15.8V.
Also, with my MULTI US 7002 this first phase lasts not even 1 second on a battery in good condition. It is not even clear that anything is even happening during this second, before the LED for the next phase lights up.
 
Ended up ordering another Noco but this time the Genius 5. CTEK’s distributor here is selling at 2x (170$) which I didn’t think is fair.
 
Just came back after 2 weeks, Macan battery practically empty, 11.5V left, after opening the locked car and waiting 30mins. Funny thing was, after hooking up the CTEK under the hood, while measuring the voltage via CAN plug (in car's idle state the same reading within 10mV as at the jump posts) it did rise to some plateau at 12.4V quickly and charged to 14.65V over night. Assuming the charge state was at that voltage level around 12.4V it was about half full. This corresponded to some 10h charging at 5A to almost full. Starting the Macan and MFD voltage reading was OK. Wonder about this voltage drop to 11.5V, eventually one battery cell defective...

Rem 1: Drove 180km autobahn afterwards, no fault messages after this event, MFD battery display first at 12.1- 12.2V, then later rising up to 13.x V. After parking the car and waiting for an hour, 12.55V (= around 3/4 charged @7c) with a CAN-Bus plug adapter to leave the car untouched, when measuring.
I am really curious, what the situation will be tomorrow morning...

Rem 2: Next morning, after 21h, car not locked overnight, I measure 12.49V, which corresponds to a battery discharge of around 5% over 1d (derived from the a. m. battery voltage calculator as a differential, which could be reasonable. This cuts out some imperfection in the absolute charge level in that model). This is quite high, considering a 95Ah battery, almost 5Ah in 24h, which corresponds to an average discharge current of 0.2A, even with disabled alarm, due to unlocked doors. Pretty high, this needs to be investigated further.
After a 10km ride to the supermarket and back with front seats and steering wheel heating on, the alternator heavily charged @15.3V (MFD), leaving a battery voltage of 12.46V and 1h parking.
One can conclude from this that a short ride with heavy load from the seat and steering wheel heating is not enough to keep the battery charge level (from the day before). Next check tomorrow morning...

Rem 3: And here comes the surprise, after another night, coming from 12.46V the day before, today exactly the same voltage 12.46V (similar ambient temperatures between 0-5c)! Today, we will probably not use the car, so I'll leave the DVM connected and see what happens next.
Another thing to test could be the influence whether the car is locked or left open, measuring the influence of the alarm system.

It looks to me as if the Macan PCM does some irregular "nightshifts" to update SW (systems & nav maps), eventually repeating them if no wireless connection to public data networks was possible (the car is parked in a low field strength area) or even to our mobile phones via BT, since we were away...this might have led to the almost discharged battery after 2 weeks of absence!?
 
A couple of things. Im not sure I mentioned this before but maybe in this long thread. There is another thread on battery analyzers.


First, yes never test at the jump points, only directly at the battery. I found that out the hard way years ago.

Second dont use EN, use DIN. When I was having problems, the service guys uses DIN. I was using EN. Never try to convert to CCA, just use what is on the battery.

Third, no one knows the algorithms used for good/bad. I think some discussion here https://www.macanforum.com/threads/battery-soh.174737/

Last, you need to temperature compensate. Some analyzers do it for you. You can look up values here


AGM has different SOC values than flooded. 12.0V at 68F is 25.8%, not good, charge
Just coming back to the quoted battery charge calculator above.
Just found their "polynomial fit to data" calculation claim to be a perfect straight line at a given temperature.
To make it easy for mental calculation: [Full]V = [Empty]V + 1.00V, so every 10mV equal to 1% discharge.

Probably as good as any other method, charge your battery, drain the excess charge voltage (wait 1d or unload some few mins with ignition on) yields a 100% capacity value, subtract 1V and you know when the battery is empty. Every 0.01V step down in between is 1% discharge. (german milk maid calculator ;) )
 
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