R230 Supply Battery AGM or Standard Lead Acid?

[DickieG]

First post so hello to everyone, a few weeks ago I bought an SL55 (07 reg fitted with the F1 Performance Package), as is common with SL's I've been having the consumers offline message showing when starting the car after a few days rest so having charged the battery in the boot I've tested the battery several times using my Midtronics tester which shows the battery to be in good condition.

However rather than the battery being an AGM (as specified in the USA Mercedes technical info document http://http://www.mercedestechstore.com/pdfs/507%20Systems%20I/507%20HO%20R230%20Dual%20Battery%20System%20%2011-28-02.pdf) the car is fitted with a standard (genuine Mercedes) lead acid one so today I visited a dealer Mercedes Colindale to purchase the "correct" AGM battery but the parts computer (using the chassis no) gave a part no of A 000 982 31 08, the very same lead acid battery as presently fitted to the car.

As I had a copy of the above technical document with me I presented that to the staff who then carried out further investigations with their technicians but they came back with the same answer as in the correct battery being the above mentioned lead acid battery rather than an AGM one which has left me rather confused to say the least.

Can someone confirm what battery would have been fitted to the car originally as I'm now wondering whether the technical document might only apply to cars built to US specifications.

 

[8678aggy]

bttery lead acid or gel

hello,i have a 2007 sl 350 and went through the same experience as you with the merc dealers,i went to andrew page who told me the car should be fitted with a gel battery,not cheap around 110 £ but was a lot better at retaining charge and was guarenteed for 6 years,unfortunately after a while this battery now loses charge but i think there is a drain on the car but it is looking for a needle in a haystack,mick

 

[SL63 Mark]

Well, the earlier 230s certainly have an AGM battery, that is what I bought from MB. The later ones may be lead acid.

 

[Monday]

My 2007 SL350 had an AGM consumer battery in the boot and a lead acid starting battery under the bonnet. As far as I know that's the standard arrangement for a 230 but I could imagine that an SL55 might be different?

The R231 still has an AGM battery but only one battery altogether, in the boot.

 

[John Laidlaw]

My 230 was a 2008 and had AGM front and back

 

[alexanderfoti]

My 2007 SL350 had an AGM consumer battery in the boot and a lead acid starting battery under the bonnet. As far as I know that's the standard arrangement for a 230 but I could imagine that an SL55 might be different?

The R231 still has an AGM battery but only one battery altogether, in the boot.

Front battery is for braking system only in normal use.

Rear battery is for everything else.

 

[BRABUS R230]

I just installed an 019 with CCA 850 lead acid battery which replaces the 4 year old AGM battery. Let's see how it goes. I was wondering if it's a choice between AGM or Lead acid battery - the question i have is does the charging rate on the R230 adjust to suit which battery has been installed.

 

[Biggus-Dickkus]

Front battery is for braking system only in normal use.

Rear battery is for everything else.

I was under the impression the front battery was for starting the engine and powering the minimum basic functions including the braking system (all be it at reduced power) to get the car going, and the rear battery powers all the ancillary equipment. That is how it appears to work in my 2009 SL350. The battery in the back can be almost dead but the car still starts very easily.

 

[John Laidlaw]

I was under the impression the front battery was for starting the engine and powering the minimum basic functions including the braking system (all be it at reduced power) to get the car going, and the rear battery powers all the ancillary equipment. That is how it appears to work in my 2009 SL350. The battery in the back can be almost dead but the car still starts very easily.

Welcome, correct and that’s wot he said...

 

[Tony Dyson]

Whatever type of battery was designed as the original should be maintained throughout the life of the vehicle as the design characteristics of the demand have been matched with the performance characteristics of the battery, additionally, the in-car charging characteristics are matched with the relevant battery technology and changing a battery type without matching the charging algorithm will result in reduced charge levels, performance and lifespan of the replaced battery.

Some intelligent out-of-car battery chargers have the capacity to identify the connected type of battery and will change the Charging Algorithm to suit but I am unaware of any such technology that exists in-car, unless of course it is mentioned specifically in your handbook!

You can increase the overall performance of a typical Wet or Flooded Lead Acid battery by utilising an EFB (Extended or Enhanced Flooded Battery), this uses the same Charging Algorithm. As for Gel batteries? I wouldn’t personally entertain the use of a Gel Battery in any automotive environment as they don’t perform well with the demanding duty cycles especially in winter, the gel easily burns and once burnt will never repair and often leads to a premature deterioration and loss of overall performance.

 

[kid-jensen]

I baulked at the price of the AGM replacement for mine and put a standard Heavy-Duty Varta one in (100 A-H) in for less than half the price

That was a few months ago, so I guess I'll see soon enough if it was false economy....

 

[LostKiwi]

AGM and Lead acid have different charging requirements. I suspect you will end up overcharging the battery if it's the wrong one.

 

[kid-jensen]

I guess I'll then find out if the 4 year Guarantee is any good.

It was Tayna Batteries who quoted it as the correct one for my car, so I hope they'll stand by it.

 

[BRABUS R230]

It's about that time for an update. AGM, GEL or Lead Acid for consumers?

 

[John Laidlaw]

AGM

 

[LostKiwi]

AGM

+1

 

[kid-jensen]

Lead-Acid (with a Supplier's Guarantee) is working fine for me so far (> 1 year).

Price was just under £100 delivered for a 95 Amp-Hour Varta.

 

[Wighty]

My AGM (for the E320cdi) from Grangemouth MB last year (ish) was £130 delivered , considering the previous battery lasted 9/10 years I thought this was a fantastic deal

 

[kid-jensen]

That's a great price. When I looked for the W164 last year, there was nothing below £240.

I'm assuming the requirements are similar.....if I could have got an AGM battery for £130, I would have!

 

[Wighty]

That's a great price. When I looked for the W164 last year, there was nothing below £240.

I'm assuming the requirements are similar.....if I could have got an AGM battery for £130, I would have!

MB Grangemouth do a forum discount , and deliver for £5