I finally replaced the 12v battery in my 2018 Clarity. I haven't had any problems with it, but I noticed a little corrosion on the negative terminal, it's 7 1/2 years old, and my wife and I are heading out next week for a 10-day backpacking trip on Santa Rosa Island (Channel Islands National Park) -- I didn't want to deal with a potential dead battery when we returned to the car. My local replacement options were Walmart EverStart Value ($82, 1 year warranty), Plus ($121, 2 years), or Maxx ($154, 3 years); Honda OEM ($195, 3 years, then prorated to 100 months); or Costco Interstate ($124, 3 years). I opted for Costco because of the price/warranty, I've had good luck with those batteries in all of my other cars, and I'm not a fan of Walmart. I was surprised that the Honda OEM battery was so expensive compared to prices reported by others on this forum. For me, it wasn't worth the extra $71 for a Honda warranty that I'll likely never use.