E89 battery question

S

Stealth00

Member
Hi everyone, I'm new to the forum, but I think there's a fair chance I'll be posting a few questions over the coming week. I'm a new Z4 owner, having just picked up a 2010 2.3i. Loving the car and it's my first 6-cylinder engine which is an absolute joy.

I was sat in it last night for about 5 minutes with the internal lights on and I noticed either a yellow or amber battery light was displayed on the dash. It still started and drove okay, but it's got me concerned now. I bought a smart charger off Amazon last night thinking I should charge and condition the battery, so I'll give that a go anyway, but today I thought I'd have a nose to see what battery was in there. It's a Trade club 096 battery, which looks newish? but looks far from high-end and doesn't appear to be an AGM type.

What's the advice here? Shall I just swap it out for an AGM type? Can anyone recommend one? I've seen in the past that sometimes it's actually cheaper going to the dealer than getting one online etc. Also, I understand there will be some coding involved.

Thanks.
 
AGM is defintely what is required..the battery needs to be 'registered' and 'coded' if its a different AH from the original one..not the one fitted..

So its either

main dealer likely to be very expensive

halfords/quick fit etc who can fit and register

buy yourself and register it yourself /find a friend

Exide, Yuasa, Varta, Bosch are tier 1 suppliers

70ah is the default capacity some cars were fitted with 80ah..in the UK either is OK 70ah cheaper
 
On the E89, the battery condition is essential for keeping so many things functioning; one fault can make lots of others appear (wrongly), as it floods the CAN (data) bus with fault codes.

You can fit something like this https://www.amazon.co.uk/gp/product/B09YTWJ6BL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 for £20 and leave it in place. It will send you a daily battery status report.

It is also a VERY good idea to get yourself a code reader. ProTool https://www.bimmergeeks.net/protool is one of the best and will display fault codes and register / code a new battery, but also clear fixed faults and set options for you. It can only connect to an Android phone, but you can pick up a very cheap second-hand one and keep it in the car - it doesn't need a SIM card for an Internet connection.

Coding / registering a new battery is important as the car has intelligent charging and so needs to know the capacity and age of the battery. The car will work without doing so, but you won't get the best out of it.
 
Give a good run first. Even with a good battery if your messing around with lights on, radio on for 10 minutes you can get the battery warning up.
But good to change about 5-6 years, might still start ok but the capacity goes down.
For instance i only operate roof where possible engine running.
Good obd can show charge history, if the last battery was coded.
 
Stealth00 said:
B21 mentioned the 70 or 80ah. I think I know the answer, but assuming no damage could be done by running the 80ah.
Click to expand...

Various E89s were fitted with either 70 ah or 80ah..

No harm comes from the 80 ah..however as stated a change either way needs coding ..that’s separate from registration which is required every time the battery is swapped out for a fresh one..of the same capacity ..both functions are covered by s/w tools as standard procedures,,
 
B21 said:
Stealth00 said:
B21 mentioned the 70 or 80ah. I think I know the answer, but assuming no damage could be done by running the 80ah.
Click to expand...

Various E89s were fitted with either 70 ah or 80ah..

No harm comes from the 80 ah..however as stated a change either way needs coding ..that’s separate from registration which is required every time the battery is swapped out for a fresh one..of the same capacity ..both functions are covered by s/w tools as standard procedures,,
Click to expand...

Thanks for confirming.
 
One other thing, before buying an 80ah one, the dimensions will be longer, I'm assuming this will fit okay and the battery holder clamp will just move over to the other bolt hole further to the right?

Oh, and the fact that I'm buying a battery that's designed for cars with start/stop is irrelevant?

PXL_20241112_172056989.png
 
Probably no bigger.
When i asked BMW if i could add Servotronic to my car, was £200 option, they said i would need to up-rate the alternator and fit 80ahr battery.
My car came with 70ahr battery.
 
Stealth00 said:
One other thing, before buying an 80ah one, the dimensions will be longer, I'm assuming this will fit okay and the battery holder clamp will just move over to the other bolt hole further to the right?

Oh, and the fact that I'm buying a battery that's designed for cars with start/stop is irrelevant?

PXL_20241112_172056989.png
[/quote

Correct 80ah slot is to the right as you highlighted..

It’s important that it’s AGM..stop /start doesn’t guarantee it’s AGM….

Some E89s are stop/start but all E89s need an AGM battery..
Click to expand...
 
peter2704 said:
need to get an AGM for mine ,think its running standard lead
Click to expand...
AGM is just an abbreviation for Absorbent Glass Mat. They are still lead-acid. The 'AGM' just have the ability to store more electrickery for a given physical size. There is no witchcraft, or special voodoo. :D
 
peter2704 said:
Thought they had better cranking my capabilities
Click to expand...
Yes they will, for a given pysical size. The CCA , or Cold Cranking Amperage rating will be stamped on the battery. Those are rated at 0oF or -18oC for 30 seconds continuously. Very unlikely to get to -18 C in the UK (especially with global warming :) ).

I am no battery expert but from what I can gather, an AGM (there are other similar technologies called different names) is favourable with 'stop start' and high cranking amp engines, as they can 'recover' quite quickly.

The battery world has moved on from AGM- type batteries for stop-start. A lot of modern cars use a small Li-ion battery to control the stop-start in addition to the main battery. These can also perform other functions, hence the MHEV was born! :D
 
Speaking of batteries has anyone gone the lithium route? I know it might be a bit overkill, but curious whats out there that would work for our cars
 
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