Buy either a group 24 or 34 battery both are similar and fit. Both are a huge upgrade from the stock group 25.

Do you camp? If you don't, no real need for AGM. Normal flooded battery will be fine and cheaper.

I went for an Everstart 34 (Walmart) a couple weeks ago. No regrets on the purchase, 800 cca and 115 minutes of reserve time.

 

Buy the largest CCA batettery that will fit in the battery holder. Pay atttention to which side the positive post is. AGM are good batteries but if you maintain the water level in a lead acid they will last for years. And yes you can add distilled water to a maintenance free battery.

Remember the warning about explosive gases being produced when charging. That is the breakdown of the water molecules (H2O) into hydrogen and oxygen. As this happens the electrolyte level gets lower and plates get uncovered. The uncovered portion of the plate no longer produces electricity. Battery is weaker. Keeping the plates covered means you are using the full potential of the battery. The electrolyte stays in the battery, the water is lost due to being converted to gas. So replace it with distilled water. If some one tells you you can replace the water, ask them how it got in there in the first place. It can be done.


Electrician’s Mate (Submarines) US Navy
(and we had BIG batteries in them)

 

The only AGM I can find is Odyssey or Optima. Duracell has one, but no one carries it. Keep getting told I have an odd size battery.

 

They are looking for the 25 size (oem), which is a bit odd.

 

here are some thoughts,

http://www.subaruoutback.org/forums/104-gen-4-2010-2014/43293-gen4-bigger-battery-group-size.html


and in Gen5. as 2013-14 2.5 engines have the same weak battery the new ones do:

http://www.subaruoutback.org/forums.../138-gen-5-2015-present/391217-gen5-replacing-original-lame-battery-better.html

 

Looking at batteries plus bulbs
Going to go for the Duracell Ultra Gold SL186M or the Optima Red Top AGM or the Duralast Gold
Someone please decide for me...

Looking into actual dimensions is driving me nuts.

ecbaatz - thanks for the great lesson on batteries!

 

Duracell batteries are made by East Penn/Deka and are good batteries,

 

o'reilly in the US resells DEKA/East Penn, they are sealed and I get no corrosion so, venting seems sophisticated.

they sell an AGM also

 

Duracell has good reviews, but their regular batteries - AAA and AA leak after a year. Not sure if I trust Duracell. Duralast has a longer warranty - maybe them
Wish I could find a place that sells Bosch

 

Okay. Went with the Optima. Looked into the Duralast - bad review. Bosch - only place is Pep Boys and they do not have good reviews here. The Duracell name just gives me hives after having to clean up batteries leaking into calculators all the time. Odyssey was just over the top expensive.

 

Crap - just found out that Optima is made in Mexico.
Wonder if there is an X2 that fits

 

Don't overthink and don't buy a cheap one! My most recent purchase was a NAPA Legend Professional, because it was the shortest drive to get a good battery. Would put the same in my OB when the time comes.

 

Thank you batteries plus. Although not listed for the outback this one fit. X2 model 34

 

I'm a big fan of vmax chargetank batteries. After years of watching optima, kinetic and other high end, high price batteries fail I finally had enough. Northstar and XS Power also make a great battery but at a higher price.

Sent from my Pixel XL using Tapatalk

 

I've seen ads for Northstar datacenter and solar products, but wasn't familiar with their automotive line. Very much a small volume specialty product with more of a footprint in Europe than the US. It isn't cheap, nor will you find them on every street corner. But the specs are impressive. Another source claims the design is based on Odyssey patents.

https://www.northstarbattery.com/product/nsb-agm-24

 

The puny little CCA battery in our 17 OB 2.5 is working fine thus far. In the frigid Chicago and Pittsburgh area temperatures, it also started flawlessly sitting in the teen's for @9 to 10 days in December. However, I wanted to provide some input on Bosch Platinum AGM batteries from Pepboys. We recently (TG sale) bought three of them, one for our 87 Brat, one for the 08 OBS and one for a 13 Suzuki SX4 SB. These come with a 4 year replacement warranty and seem to be great; of course they are brand new. Not sure where the negative reviews for the Bosch are coming from (reference to post # 11 above)? It is the performance, the warranty, Pepboys or what?

 

Original is typically Group 25. Folks typically replace with Group 24 or Group 34 as they have greater capacities. You could go with the same size too - probably Group 25.

I am not convinced you "need" AGM but if it is the same price/on sale as a normal wet cell - why not. AGMs can be pretty pricey depending on the brand.

 

With the 30% off coupon and the $30 rebate per battery, the Bosch Platinum AGM's from Pepboys were a sweet deal. Cannot beat these batteries for @$100 to $105 each total, after the discount and rebates. Look out for sales at Pepboys.

 

Just beware that although on paper an AGM battery is superior to a flooded cell battery, it might not perform as well as it should when installed in a Subaru.

I would lean towards NOT putting an AGM battery into a vehicle that did not come with one as standard equipment, or that didn't have some serious thermal isolation. AGM is conceptually better than a flooded cell battery, but there are downsides. They are sensitive to heat, and charging at an aggressive rate when they are too warm can damage and short-life them. There is a very specific taper rate recommended, especially when the temperature is elevated. The alternator of our generation cars is probably not computer controlled to the level required to meet this.

Will you get away with it? Maybe. But look at cars that came with an AGM and you'll find that the battery was either in the trunk, or isolated from the engine by a partition or a thick thermal shell (and not that silly cozy that comes with the Group 25 battery).

If there is no price differential, then go for it. If you are paying 2x what a conventional flooded cell battery would cost, I'd pass.