Battery OPTIMA or Varta

I've put my trust in Varta. Previously had Bosch. I think you can put your trust in pretty much any brand if its covered by a 2-year warranty.

I remember this very interesting post a couple years back regarding AGM batteries and their charging requirements: On the one vehicle that I modified the charging circuit to run at 14.7V I have an Optima Redtop battery in it that has never been replaced. And this includes repeated discharges to near 0% SOC when the sales people at the tradeshows forget to turn the vehicle off after the show.

I always hear people talk about issues with newer Optimas but my old REDTOP is going on 13 years old and still going strong.

i have a optima red top in my drift car. its been in the car for atleast 4 years. 3 of which i have owned it. its been crushed, deformed, on fire and drained dead multiple times (always when diagnosing electrical issues or wiring up lights) and it still works great. it sits in my car hooked up and unused for weeks at a time with no issues.

We needed to replace the original German Varta battery in our '14 A4 (date code Jun '13) after the first polar vortex in early '19. OE list was $227 (non AGM), discounted to about $195 at the local Audi parts counter. Advance Auto had an equivalent H9 for about $170, but the local store only had one with a late '16 date code (and proper BEM sticker). So they sold it to me as a \"used battery\" (after running their condition test and passing) to me for $45 + tax. Two years later, so far, so good.

I have a pair of Optimas (older) and they're dead-ass solid.

They’re pricey but I’ve always sworn by Optimas

The yellow top is what I have in my car and there is one issue I have with it, the amp hour rating. The yellow top is only 38a/h where the OEM is about 45a/h. This will lead to the inverter using a lot of energy charging the 12v battery and decrease fuel efficiency.

Optimas are garbage. Mine didn't survive a 3 month work assignment. The battery was less than 2 years old, and fully charged when I left. Dead when I came back. Blew up like a football when I tried to charge it.

Service guy just stopped over and confirmed the battery was bad. Replacement installation in progress.