Why so hard on batteries info..

[ArmyRn33]

As a new owner of a x5 50i I had read about the need for batteries due to it being hard on them, found an article detailing why the need and the technical reasons. Hopefully this will help new owners, if this has been shared please let me know and I'll take it down... http://www.roadandtrack.com/car-cult...ns-bmw-n63-v8/

[crackerjack15]

No clue, but I would guess it's also related to people who do short trips and use start/stop feature. They replaced mine at my last oil change. I hate the start/stop.

[P1]

Turn off the start/stop. Hard on the batteries.

[kanvas]

That's why I bought a battery tender. Hook it up every month and keep the battery in good health.

[apexit]

I wonder if this would be a concern in the F8x running in Sport+ mode. It adds a lot of extra cooling but I'm not sure if it extends the cool down period after the engine is off.

[boyce89976]

I think the real culprit is the short, frequent charging cycles the battery is subjected to due to the efficient dynamics programming. Battery life should really be defined in the number of charging cycles... it's probably the single most important battery stat behind current availability.

[Apple Corps]

Not per the article - it is the tremendous heat soak created by the inboard turbo design that requires the cooling system to run for longer periods - that draws the battery down deeply and frequently. The "efficient dynamics" design contribution was handled by the AGM battery.

[boyce89976]

Originally Posted by Apple Corps

Not per the article - it is the tremendous heat soak created by the inboard turbo design that requires the cooling system to run for longer periods - that draws the battery down deeply and frequently. The "efficient dynamics" design contribution was handled by the AGM battery.

There was another article that also cited the frequent, short charging bursts as a cause.

Batteries typically don't mind deep discharges as much as frequent, incomplete charging. For example, your cell phone battery is probably rated at 1,000 charging cycles. "Charging cycle" is defined as anytime a charge is applied to the battery, whether its a partial or full charge. Charging once a day, you should get about 3 years of battery life expectancy. Charge more than that (which most people do) and it can shorten significantly.

[Apple Corps]

If that was the primary cause than most cars would be requiring battery changes at these frequent intervals - I believe it is the massive electrical draw associated with keeping the heat under control from this engine design.

Whatever the cause - it sucks...

[boyce89976]

It definitely sucks. If I have to buy a battery at every oil change after December when my factory warranty is up, I'll be selling the vehicle.

It's both issues... deep discharge + short frequent charging cycles = battery never reaching a full charge, and an inability to keep up with the draw. After a while, there's not enough charge left in the battery.

[Habs11]

Originally Posted by kanvas

That's why I bought a battery tender. Hook it up every month and keep the battery in good health.

For those no longer under factory warranty - is there any reason this is not a good option?

[kanvas]

Originally Posted by Habs11

For those no longer under factory warranty - is there any reason this is not a good option?

What do you mean by "if there's a reason this is not a good option"?
You will still need to change up the batteries but what I'm doing is not so I don't change my batteries, but that I can lengthen its life by a little bit. The other day, I was surprised that it needed to be hooked up ~4 hours until full charge.

[Habs11]

Originally Posted by kanvas

What do you mean by "if there's a reason this is not a good option"?
You will still need to change up the batteries but what I'm doing is not so I don't change my batteries, but that I can lengthen its life by a little bit. The other day, I was surprised that it needed to be hooked up ~4 hours until full charge.

What are the negatives to what you are doing? That's what I'm asking.

[ted99]

No negatives. I put my 528i with "efficient dynamics" on the battery maintainer whenever I park it. When car went in for second service, the computer said not necessary to change battery, as most cars do. My wife's car has frequent short trips and if left to it's own devices, battery would never be fully charged. Key is a quality maintainer that doesn't overcharge. The BMW accessory charger is a CETEK, which is available on e-bay for half BMW's price. If you have a plug-in hybrid, the high voltage battery keeps the 12v battery charged up, so maintainer not necessary.

[boyce89976]

Talked to my SA about this today. The auto start/stop is the biggest drain on the battery according to her. She said the battery life is 3-4 years in the X5 with all the sensors, auto start/stop, etc... , but BMW is changing them more frequently to avoid any issues with customers.

[Dilmorecg]

I coded my auto start/stop off because I feel it puts extra strain on components...including the battery. My driving is mostly short spurts so hopefully I wont have an issue going forward once the factory maintenance is over.

[Maverik259]

I've been using battery tender plus (Amazon) for years on my R1 and now my AMG that I don't drive often and it works great. Even have a lithium option because I'm running a Li- battery on my R1 because it lasts longer than AGM/cell batteries in between starts.

[ArmyRn33]

For those who have extended warranties does the battery change out last as long as your warranty or does it end after the initial 48 / 50 k for me time frame?

[boyce89976]

^My SA said batteries are not covered by extended, or CPO, warranties since it's a customer service action and not technically a warranty issue.