Is this a record for battery life.

[BTB 500]

Have just sorned the car whilst the lockdown continues and didn't want to trust 12 year battery to let me back into the car after standing.

Ah, OK. My SL (with the 16 year old battery) sometimes goes for months without moving, but is kept on a maintenance charger. I guess that's not an option for you? Quite a few cars have a reasonable parasitic drain from the electronics while parked up now, so you could eventually have issues even with a new battery.

 

[Gbrowncls55]

I have both a w219 cls and a 2005 r230 and as I understand it/ was told somewhere, the role of the front battery is different in each. In the 219 (and 211for that matter) the front battery maintains voltage for the systems should the rear battery voltage drop too low, but on the r230 i thought it only satrted the car. Certainly after a long break and a rear battery so flat it wont even open the locks the car will still start easily. But could well be wrong.
Incidentally I only replaced the front secondary battery in the cls (55plate) last year and the old one was the original, so 14 years old .

 

[Monkeylegend]

Not according to the traffic light indicator which goes to amber whilst rear battery is green.
Also when the main battery is on charge for some time boot battery goes to red as a result of me opening & closing the boot etc. Main battery is marked 2019 (see photo) and is a normal lead acid battery whereas the boot battery is AGM so I have to re set the Cetek accordingly.

I have a 2004 SL350 and was told by a very well respected indy that attaching the charger to the auxilliary battery will also keep the starter battery fully charged. I have done this for 4 years now and he has so far been proven to be correct.

However I have also found that attaching the charger to the starter battery does not also keep the auxilliary battery charged.

 

[Larkone]

Ah, OK. My SL (with the 16 year old battery) sometimes goes for months without moving, but is kept on a maintenance charger. I guess that's not an option for you? Quite a few cars have a reasonable parasitic drain from the electronics while parked up now, so you could eventually have issues even with a new battery.

Can't use a maintenance charger as the lead would have to across a lot of gravel driveway and either the postman or the wife will argue with it at some point. I know there is a certain amount of drain with these (alarm etc.) but the point of a nice new battery is that it is likely to have a bit more life in it than a 12 year old battery. I intend to check at regular intervals anyway. Having been locked out of the boot once and the key not working it was only the fact the doors were unlocked that I could open the bonnet and connect a battery into the fuse box to get the boot open. Don't want that happening with all of the doors locked. If I could be bothered I would fit a charge lead to the battery that could be accessed from outside, but that would need to be waterproof etc etc Can i be bothered??

 

[BTB 500]

Yep I can see you would be better off with a new battery, and you definitely don't want a power cable running across the drive. As an aside, our Vito and C Class (both 2007) have uprated (higher capacity) batteries. This was a factory option ... wonder if it also applied to the CLS, and whether it can be retro-fitted (assuming your car doesn't already have it)?

 

[Will]

Strange to think that so many people struggle with access to power for a maintenance charger, but in the not too distant future it is expected that most will have plug in EVs!

 

[anglaslt]

With current restrictions I've been watching a bit more tele than usual. I was recently watching an American classic car programme where a 1923 Stutz Bearcat had been found stored and unused for around the past 70 years. Apart from some minor engine work the car was up and running and everything worked.
The battery was the original fitted in 1923. Now that may well be a record .

 

[BTB 500]

With current restrictions I've been watching a bit more tele than usual. I was recently watching an American classic car programme where a 1923 Stutz Bearcat had been found stored and unused for around the past 70 years. Apart from some minor engine work the car was up and running and everything worked.
The battery was the original fitted in 1923. Now that may well be a record .

I watched that last night (Chasing Classic Cars, it was a 1921 car btw!), but missed the bit about the battery. I know there have been WW2 aircraft recovered from the bottom of the sea with batteries that weren't completely flat and recharged fine!

 

[Merc220cls]

As regards to the much older vintage batteries, they are built much stronger than most modern ones of today where they are considered a dispensable item.
I remember as an HGV mechanic our electrician used to wash out batteries and re fill them with fresh electrolyte (acid) then re charge them where they would still give a reasonably active life.

I’ve looked through the invoice folder for my car and I have an invoice dated Nov 2007 where the battery was replaced “due to a defective cell” at a cost of £99.57 plus Vat but it doesn’t say which battery, mileage was only 6,669
Battery part number MA004 541 86 01/26

 

[anglaslt]

I watched that last night (Chasing Classic Cars, it was a 1921 car btw!), but missed the bit about the battery. I know there have been WW2 aircraft recovered from the bottom of the sea with batteries that weren't completely flat and recharged fine!

You're quite right it's a 1921. Just found this article that suggests the car has now been sold on at a cool profit of $ 1/2 million. So Wayne's dream of owning a Stutz Bearcat didn't last long

Stutz Bearcat

 

[jc62b]

I’ve had my 2004 350SL for a year now and just prior to purchase a new starter battery was fitted to the front.
The rear auxiliary battery which is an AGM battery is a 2008 and I have the receipt when it was fitted.
I have a Cetek charger with the traffic light connectors on both batteries and during the winter I’ve alternated the charger between both batteries to keep them topped up.
I’ve now used the car on few trips already this week and everything’s running tickety boo with the roof working fine and vacuum locks etc all working.
I’m really surprised this 2008 battery has lasted so long so is it a record. ?

View attachment 97421

 

[jc62b]

Sorry, but no it’s not a record, this is a record. Apologies,I couldn’t resist.

 

[190]

Not so , hot weather- excessive under bonnet heat - can cause (older type) batteries as many problems as cold weather.

No question that heat is a battery killer. If we all lived in Texas there would be nobody claiming 12 year battery life, it would be more like 3 - 5 years at best.

Perhaps one reason our batteries are lasting so well is that they are located in their own compartment and protected to some degree from under bonnet temperatures.

 

[219]

Sadly , that isn’t a record .
When a Fairey Barracuda seaplane was recovered after 76 years on the seabed , one of its batteries was found still to hold a charge ( albeit not much ) .

Batteries inside sea plane that sunk in 1943 still work

The Royal Navy Fairey Barracuda sea plane was found by accident during a seabed survey of the Solent and was recovered from the waves in June this year.

www.dailymail.co.uk

 

[219]

Can't use a maintenance charger as the lead would have to across a lot of gravel driveway and either the postman or the wife will argue with it at some point. I know there is a certain amount of drain with these (alarm etc.) but the point of a nice new battery is that it is likely to have a bit more life in it than a 12 year old battery. I intend to check at regular intervals anyway. Having been locked out of the boot once and the key not working it was only the fact the doors were unlocked that I could open the bonnet and connect a battery into the fuse box to get the boot open. Don't want that happening with all of the doors locked. If I could be bothered I would fit a charge lead to the battery that could be accessed from outside, but that would need to be waterproof etc etc Can i be bothered??

A solar charger left on the parcel shelf or dashboard ( whichever better gets the sunlight ) will keep your battery topped up

 

[rf065]

No question that heat is a battery killer. If we all lived in Texas there would be nobody claiming 12 year battery life, it would be more like 3 - 5 years at best.

Agree, my 2005 CLK still has the original battery and in all those years of ownership I have only ever had one instance of battery trouble, i.e. certain functions shutting down etc. This was in S. France at a time when I was doing hundreds of miles every day in temps of 40-44C, never had a problem before or after.

 

[Petrol Pete]

Back to my post regarding hot battery failing. I said I replaced the original battery in my 2006 C55 as a 'precaution' I have also mentioned (many times ) that the car has never failed to start in cold conditions even after standing for many weeks.

What prompted me to replace it was on a few occasions last summer the car - when very hot after a 'spirited' drive - had real trouble cranking over , just like you would expect to experience in only the coldest of mornings. The first time was after the car stood for about 10 minutes after re fuelling, it felt like I might need a jump start right there by the pump ! but she fired up.

This was not excessive cranking al la CPS fault as I had already replaced the CPS a few weeks before, but very slow ,flat battery style cranking.

The C55 AMG holds a LOT of heat under the bonnet and that got me thinking , this was the first time for me that any vehicle I have driven or ridden had trouble cranking over when hot. A quick search on the internet promoted me to change the battery.

A battery that had never hinted that it would ever let me down in the very coldest of conditions ...but might fail me when hot.

As soon as the new battery went in the 'fault' went away.

 

[Larkone]

A solar charger left on the parcel shelf or dashboard ( whichever better gets the sunlight ) will keep your battery topped up

Agree and I have a solar charger but it doesn't work when it is under a car cover to keep the endless pigeon sh*t off.

 

[190]

When mentioning battery in use at elevated temperatures I was thinking of the long term effect on battery life. As in any other chemical reaction the internal self discharge rate increases with temperature. There is a rough rule of thumb that for every 10 deg increase in temperature above 25 C the battery life is halved. I know someone who lives in Arizona where the temperature regularly rises into the mid 40's and his experience is that a battery will only last 3 years.

 

[BTB 500]

When mentioning battery in use at elevated temperatures I was thinking of the long term effect on battery life. As in any other chemical reaction the internal self discharge rate increases with temperature. There is a rough rule of thumb that for every 10 deg increase in temperature above 25 C the battery life is halved. I know someone who lives in Arizona where the temperature regularly rises into the mid 40's and his experience is that a battery will only last 3 years.

On that basis we should see a huge difference between the lifespan of batteries mounted in the engine bay (where they are exposed to high temperatures whenever the vehicle is driven for any length of time) and those in the boot (which aren't)??