It's battery research time so many different aspects!

1 what's the difference between sealed lead acid and non-sealed (with caps where you can refill with water) lead acid batteries? My OEM one had screw caps; I notice that even the later (2010+) XK's come with OEM screw cap types. The local battery guys claim that 'screw types are the older ones and nowadays they're all sealed'. Not too sure about this claim! Any thoughts?

2 Batteries like some of the Bosch ones state that they're 'silver calcium' rather than lead acid. These apparently need higher charging voltage than lead acid. Any concerns of using these instead of lead acid ones?

Grazzi!

 

I agree with the store clerk. I prefer the sealed as there is no maintenance. If you like keeping a container of distilled water around and like diddling in this matter, then, go for the screw cap. If one has a classic car and wanting to keep it true to it's origin, then the screw cap models would be warranted.
A sealed battery allows the manufacture to place the battery in the trunk, much like my '04 XJR, as there is no out-gassing.
The more important aspect, is the "CCA" or cold cranking AMPs. I typically go for the highest available in the size I need. This is especially important for those folks in very cold climates, as they cranking interval may be needed.
When you deviate outside the lead acid varieties, there are a few challenges to consider. One being, the type of charging media may be such they special chargers to rejuvenate them.
Just my 3.5 cents. Happy Motoring....

 

Ken, what an E-type/Mustang combination! I'm sure this must be one of the enviable combination; tell us your experience to the XKR when you get hold of her!

I believe there would still be vents on the sealed batteries, though?

 

There is a vent on the standard battery, and there's a vent tube to connect to it.

 

ejjbee:

I have the same Jaguar...2009MY XKR ... I have a sealed lead acid battery and have had NO reported problems with this type of battery.

I don't think there is any need to over complicate the issue of battery replacement.

 

Ditto!

 

I think the XK is the same as the S-Type, where the battery is vented and the charging system adjusts its voltages to suit that kind of battery. It does not appear properly to suit other kinds. I expect they will work, just not optimally.

JTIS has details of the charging voltages.