Halfords BMW 520d battery not the correct spec?

irish bloke · 20-01-2014 12:51pm #1

Changing battery on 06 BMW 520d

Bought a Yuasa 100Ah 900A battery from Halfords yesterday that was recommended for my car spec.
The battery previously in the car was a BMW 80Ah 640A. It is also recommended in some circles that you upgrade the battery in these cars due to the original not been powerful enough.
Height and width of these 2 batteries are identical, with the new battery being 43mm longer. This is not a problem as the car has 3 battery locking positions and the Halfords battery is the middle size allowed with the original been the smallest.

The problem lies when I go to modify the cars program to tell it it now has a 100Ah battery installed and to charge at this rate.
There are only a certain amount of options available to me using the coding program “NC expert” to change the battery Ah.

Starting from 80Ah, there is 80Ah, 90Ah and 110Ah. Considering I was sold a compatible battery from Halfords, the option to code the car for 100Ah is not there??
I have coded the batter to 90Ah and registered the new battery program “DIS v57” but the questions I have are as follows:

a) Should I code the car to charge at 90Ah or at 110Ah, issues been under and overcharging.
b) Should I go back to Halfords and tell them they are selling the wrong batteries for my car and get my money back
c) Should I not be concerned at all and the ± 10Ah of charging will make no difference to the life expectancy of the battery.

Thanks.

jimgoose · 20-01-2014 12:56pm

Cheeses, talk about unnecessary complication! Leave it on the 90aH setting, and as long as the car puts 14.3v or so across the battery at idle it'll be grand.

irish bloke · 20-01-2014 1:03pm

jimgoose wrote: »

Cheeses, talk about unnecessary complication! Leave it on the 90aH setting, and as long as the car puts 14.3v or so across the battery at idle it'll be grand.

I was looking for a more technical answer than "it will be grand" or the obvious sarcasm.

If you don’t know the answer, that’s fine.
If you do know, please let me know.

Thanks

jimgoose · 20-01-2014 1:05pm

irish bloke wrote: »

I was looking for a more technical answer than "it will be grand" or the obvious sarcasm.

If you don’t know the answer, that’s fine.
If you do know, please let me know.

Thanks

I do know the answer. See above. And, please point out the sarcasm in my reply?

irish bloke · 20-01-2014 1:17pm

Sarcasm = Cheeses, talk about unnecessary complication!
So you are intimating I set the battery to undercharge at -10Ah. Can you please provide a technical explanation as to how this will have zero impact on the life expectancy of the battery.

Regards

jimgoose · 20-01-2014 1:22pm

irish bloke wrote: »

Sarcasm = Cheeses, talk about unnecessary complication!
So you are intimating I set the battery to undercharge at -10Ah. Can you please provide a technical explanation as to how this will have zero impact on the life expectancy of the battery.

Regards

"as long as the car puts 14.3v or so across the battery at idle".

A modern automotive regulator adjusts alternator output by varying the current to the armature windings within the generator itself (this contrasts with the primitive shunt regulator used by most motorcycles) and, with regulators typically set to about 14.3v, this happens automatically and relatively simply without the requirement for further complication. This is considered the correct voltage for charging the six voltaic cells within a typical automotive battery, and any more brings the risk of overcharging and damaging the unit. Hence, I would tell the computer it's a 90aH unit and measure the actual charging voltage across the terminals myself.

irish bloke · 20-01-2014 1:44pm

jimgoose wrote: »

"as long as the car puts 14.3v or so across the battery at idle".

A modern automotive regulator adjusts alternator output by varying the current to the armature windings within the generator itself (this contrasts with the primitive shunt regulator used by most motorcycles) and, with regulators typically set to about 14.3v, this happens automatically and relatively simply without the requirement for further complication. This is considered the correct voltage for charging the six voltaic cells within a typical automotive battery, and any more brings the risk of overcharging and damaging the unit. Hence, I would tell the computer it's a 90aH unit and measure the actual charging voltage across the terminals myself.

Do you think the IBS (Intelligent battery sensor) installed in the BMW for monitoring and controlling battery current, voltage etc will have any problem performing now that I have told the car there is a lower Ah battery installed.

If it were not an issue to put in any Ah powered battery, then why would BMW code these cars to their specific Ah outputs, also why would they need to tell the ECU that the battery is new if the system was not be consistently monitored and controlling for maximum performance.

jimgoose · 20-01-2014 3:24pm

irish bloke wrote: »

Do you think the IBS (Intelligent battery sensor) installed in the BMW for monitoring and controlling battery current, voltage etc will have any problem performing now that I have told the car there is a lower Ah battery installed.

If it were not an issue to put in any Ah powered battery, then why would BMW code these cars to their specific Ah outputs, also why would they need to tell the ECU that the battery is new if the system was not be consistently monitored and controlling for maximum performance.

IIRC the IBS does little more than measure the battery terminal voltage via a shunt, and advise the car's main computer about turning off various accessories to prevent the car getting "paperweighted". The shunt reading tells it all it needs to know about the state of charge regardless of the battery's rated capacity. I don't believe it even has any input into the charging process.

irish bloke · 20-01-2014 5:03pm

jimgoose wrote: »

IIRC the IBS does little more than measure the battery terminal voltage via a shunt, and advise the car's main computer about turning off various accessories to prevent the car getting "paperweighted". The shunt reading tells it all it needs to know about the state of charge regardless of the battery's rated capacity. I don't believe it even has any input into the charging process.

I thought current feed to the batt was regulated via constant current monitoring via IBS or other, but also not sure about this.
Assuming the charging sequence just works via the voltage regulator, i.e. keeping the battery at a steady 14.3v for instance. Why would there be preset Ah settings inside the control module.

My guess is this is to charge the batt at the correct current load in the correct time. If the batt is charged at 10% less current it will take longer to charge than expected, thus confusing the power management circuit and potentially diminishing the battery life expectancy.

fleet · 20-01-2014 5:11pm

Battery capacity varies (falls!) depending on conditions such as age, temperature and condition.

I don't know anything about BMWs, but I doubt they are doing anything fancy with the battery beyond measuring output voltages.

bmstuff · 20-01-2014 5:18pm

Code the cas module to 110ah, not 90.
Dis to register a new battery is overkill. Used to be the way alright.

jimgoose · 20-01-2014 5:19pm

fleet wrote: »

Battery capacity varies (falls!) depending on conditions such as age, temperature and condition.

I don't know anything about BMWs, but I doubt they are doing anything fancy with the battery beyond measuring output voltages.

At worst, I believe the car might start shutting down non-essential accessories a little before strictly necessary. This will not be a problem unless a fault develops with the charging system or the battery. The important thing with that IBS system is to reset it so that it starts gathering fresh stat data about the new battery, particularly with regard to voltage vs. current draw.

jimgoose · 20-01-2014 5:33pm

bmstuff wrote: »

Code the cas module to 110ah, not 90...

Would that not have the thing expecting higher currents for given voltages, and thus lead to excessive whine from the iDrive??

SleeperService · 20-01-2014 5:58pm

fleet wrote: »

Battery capacity varies (falls!) depending on conditions such as age, temperature and condition.

I don't know anything about BMWs, but I doubt they are doing anything fancy with the battery beyond measuring output voltages.

ARM microprocessors might be overkill for measuring a voltage....

http://www.autoblog.com/2006/10/18/sae-convergence-2006-bmws-intelligent-battery-monitoring/

irish bloke · 20-01-2014 7:53pm

bmstuff wrote: »

Code the cas module to 110ah, not 90.
Dis to register a new battery is overkill. Used to be the way alright.

Used DIS to register batt as don't have Toolset 32 and my INPA program is the wrong version for my car.

Would 90Ah not be better than 110Ah here??

bmstuff · 20-01-2014 8:20pm

jimgoose wrote: »

Would that not have the thing expecting higher currents for given voltages, and thus lead to excessive whine from the iDrive??

Absolutely not. If you do some digging you will find out those batteries are never fully charged. About 80%. That's the way it has been designed by bmw.

bmstuff · 20-01-2014 8:23pm

irish bloke wrote: »

Used DIS to register batt as don't have Toolset 32 and my INPA program is the wrong version for my car.

Would 90Ah not be better than 110Ah here??

Any version of inpa will do for your car. Your files are bad that's all. Any of those packages you buy from the Internet lack some serious updates.
110ah is what you should go for.

jimgoose · 20-01-2014 8:29pm

bmstuff wrote: »

Absolutely not. If you do some digging you will find out those batteries are never fully charged. About 80%. That's the way it has been designed by bmw.

So I heard. That's to do with the regenerative braking thing, is it not?

irish bloke · 20-01-2014 9:57pm

bmstuff wrote: »

Any version of inpa will do for your car. Your files are bad that's all. Any of those packages you buy from the Internet lack some serious updates.
110ah is what you should go for.

Using BM technic package. It's a tidy piece of kit with most applications included. Decent OBD2 cable also. Maybe the INPA will as I may not be fully familiar with it yet. Either way I got the result I wanted

bmstuff · 20-01-2014 10:40pm

jimgoose wrote: »

So I heard. That's to do with the regenerative braking thing, is it not?

That's it yeah if you run an history on the battery charge using ista for example you will see it is more or less 80-85%.
I discovered that recently myself while diagnosing an overcharging issue on a e60.

bmstuff · 20-01-2014 10:44pm

irish bloke wrote: »

Using BM technic package. It's a tidy piece of kit with most applications included. Decent OBD2 cable also. Maybe the INPA will as I may not be fully familiar with it yet. Either way I got the result I wanted

It is good yeah but has many flaws especially around daten files.
And I did not like the way the guy behind it locked many things, with password etc and even hide some executables so you could not find them on the file system without going to some advanced properties.
Anyway plenty of versions out there.

irish bloke · 20-01-2014 10:49pm

bmstuff wrote: »

It is good yeah but has many flaws especially around daten files.
And I did not like the way the guy behind it locked many things, with password etc and even hide some executables so you could not find them on the file system without going to some advanced properties.
Anyway plenty of versions out there.

Must take a look for some other versions.

FYI. The BM technic business ceased trading a few months ago. Not exactly sure why but there are a few rumours floating around.

bmstuff · 20-01-2014 11:33pm

irish bloke wrote: »

Must take a look for some other versions.

FYI. The BM technic business ceased trading a few months ago. Not exactly sure why but there are a few rumours floating around.

Yeah bmw went after a few of those sites recently.
To my knowledge bmw tools are probably ones of the most shared online.

Halfords BMW 520d battery not the correct spec?

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