The AGM Battery

[10/10ths]

If they are over rated, then why do OEMs invest in AGM batteries in their Auto Stop/Start versions of their cars?

If they didn't work better, they wouldn't spend the money to put them in those vehicles.

I bought this one:

NSB-AGM 94R/L4

I keep it alive with this:

CTEK Multi US 7002 - CTEK Battery ChargersCTEK Battery Chargers

Two years in, so far, so good. Car sits a lot.

Good luck.

[PaulE]

Originally Posted by 10/10ths

If they are over rated, then why do OEMs invest in AGM batteries in their Auto Stop/Start versions of their cars?

If they didn't work better, they wouldn't spend the money to put them in those vehicles.

I bought this one:

NSB-AGM 94R/L4

I keep it alive with this:

CTEK Multi US 7002 - CTEK Battery ChargersCTEK Battery Chargers

Two years in, so far, so good. Car sits a lot.

Good luck.

Maybe it's just overkill for an older car without auto start/stop? I am only on my second battery in my 03 S, it is an Interstate that I put in in 2009 to replace the original battery. I use the older version of that CTEK - same as the one Porsche sold at dealerships but without the "Porsche" label and premium pricing. If I can get this long out of a traditional battery (OEM -6 years, Interstate - 7 years and still kicking), what's the benefit of AGM to me?

Now that I've said that, my Boxster has been out at the body shop for a week, and then goes back to my independent garage for installation of the sport suspension. With the car off the battery tender for that long, I may have just cursed my battery!

[Gelbster]

Cursed ?
No
It is just chemistry. If the SOH is 50% or less but it still takes at least 90% charge, try to desulphating it. That is the specific problem that causes most lead+acid batteries to fail.

[particlewave]

Originally Posted by 10/10ths

If they are over rated, then why do OEMs invest in AGM batteries in their Auto Stop/Start versions of their cars?

If they didn't work better, they wouldn't spend the money to put them in those vehicles.

The 986 is not a stop/start vehicle. It's also not a hybrid or electric vehicle. AGM is overrated and your statement is a prime example of that.
When was the last time you made an AGM battery? I worked for Johndon Controls for years, so take my word for it. They are a waste of money in most cars.

[10/10ths]

...I don't understand.

How was my post an example?

[911monty]

Originally Posted by particlewave

The 986 is not a stop/start vehicle. It's also not a hybrid or electric vehicle. AGM is overrated and your statement is a prime example of that.
When was the last time you made an AGM battery? I worked for Johndon Controls for years, so take my word for it. They are a waste of money in most cars.

Well Particle I have a question then. Isn't a prime advantage of the AGM is that it doesn't outgas as much? Doesn't this help to prevent corrosion on terminals and lessen gasses in the enclosed frunk?

[Gelbster]

That is why there is a vent hose on the car. Otherwise ,yes.

[911monty]

Originally Posted by Gelbster

That is why there is a vent hose on the car. Otherwise ,yes.

I understand and this is specific to the boxster, however the statement was that it is overkill for most cars. The lack of a vent and corrosion on terminals on most other cars makes this a highly valuable feature. I'm a fan of additional protection and don't like to see corroded terminals on any car I own.