I have heard some bad things about Optima since they started manufacture in Mexico.
For my $$$$, the Deka East Penn AGM is the best choice, the "Intimidator" ( Made in USA )

Deka Intimidator AGM Batteries

 

Kind of an "Intimidating-looking" battery.

 

Yea, had to get my courage up to install it when I unboxed it ( a couple of beers worked though )

 

The battery produced by Interstate is a good choice and several owners use this one when replacing the XFire's battery. But there are lots of Interstate-sourced batteries as they produce for a wide variety of aftermarket sellers. I quit trying to keep up with battery producers & who they supply batteries for.

I have a Durcell Ultra in my Coupe now, having replaced the original Varta battery after 9 years. Started getting the weird-acting spoiler function, which is an early warning signal of a battery issue. Bought the Duracell from Batteries Plus when they had a fairly good sale. Duracell is sold by either Costco or Sam's Club, don't remember which, but either source typically has good pricing.

Only decision required is whether your want a conventional or AGM design. And another thing - batteries for the XFire do vary in casing size somewhat. The so-called standards used by the battery producers is short of being a standard (MHO). What we find is the height of the case varies enough that the holddown clamp doesn't fit exact. Some folks have had to add a rubber" spacer" under the clamp to get a secure fit. In my case, the Duracell case is slightly taller and I bent the clamp to avoid excessive side pressure on the leading edge.

 

I have brought several batteries back to life with a manual charger.
Float chargers will only charge if there is some charge in them, but hook up a manual set on 10 amp for a hr, then switch to 2 amp for a day then just set a float charger on it and let it finish and gtg.

I only get agm or better.
Odyssey makes some great batteries.
Got some lithium cells to play around with and try.

 

To "restore" a battery you need a desulphating charger. Any more I only buy AGMs for my cars they last A Lot longer in Florida.


My Crossie has a Sears DieHard Gold AGMp/n 50748 bought on sale two years ago. My other cars mostly have Duracell AGMs from Sam's Club but those seem to be on sale only at Christmas.


Interstate also had good batteries but it all depends on what is on sale and where.

 

Thanks. I'll look into that one! I was considering an Interstate AGM anyway and it was more expensive. Seems to be just the ticket for guys that store the car for 5 months a year.

I was also able to confirm no Optima battery will physically fit XF without making a custom battery tray for it.

 

As in...the spoiler goes up for no reason upon start?

While in winter storage I start mine every 4-5 weeks. It does that maybe 75% of the time. Never during summer when I drive it. Makes sense it's the battery then.

 

Yes - Got to the point that the spoiler consistently would raise whenever I started the car & drove it. Figured 9 years from the OEM Varta was probably long enough.