The Clarity seems to regularly draw on the 12v battery when just sitting. Plenty of posts about that scattered around. I'm partial to AGM batteries anyways to help prevent some issues like this (& also running various in-car electronics), but haven't decided on what to replace my original battery with yet. The Clarity is one car though that I will keep jumper cables in no matter what for that reason. Already had a situation where it had to be jumped in my driveway.
If you want a jump assist device that isn't jumper cables or one of the li-ion jumper batteries, check out something like this -
https://www.amazon.com/gp/product/B086L29DL9/ref=ox_sc_saved_title_6?smid=A2HH6L22S81Q7B&psc=1 It's a capacitor based device, interesting how it works. It obviously won't help with a truly dead battery, but is a pretty decent device for it's use case and doesn't rely on keeping anything charged.
I'd recommend a battery tender of some sort (Battery Tender Jr for example) - they're pretty cheap. Useful thing to have around the house. I typically put it in our batteries at least 2 times a year - when it starts getting cold out, and in the spring. If there's a forecast for a deep cold spell, I'll also put it on all our vehicles before that. Also if I let a car sit for awhile. Easy enough to put it on overnight or such - but it can take longer if the battery is particularly weak. After having to jump the aforementioned Clarity battery last week, it took a solid 2 days for the tender to finish it's job though. I've easily gotten 7-8yrs+ on all sorts of batteries doing this routine (not just auto - works well for lawnmowers too). Last winter I replaced an 8 year old battery (it was a bit weak, but mainly replaced because I'm driving that car alot less - need to sell it) and another is still going and will be 9 this winter (I'm selling it soon, otherwise would replace this winter). Had it grumble a tad last winter, but only during a particular cold snap and putting the tender on it led to no further issues the last week of that stretch (or since).
As for actual batteries, some tips -
- There are only like 2 major battery manufacturers in the US (+a 3rd smaller company if I recall). All of the brands are just relabeled typically. You can look up who makes what, but a $180 battery at one store is often just the same as a $80 battery at another place. You're just paying for a sticker, and maybe a bit of a warranty.
- The main choice is probably going to involve deciding if you want an AGM battery, and then looking at warranties & prices.
- For warranty considerations, the Honda battery as mentioned above is pretty decent. It's actually more of a 95 month battery warranty since I believe the last 4 months are 0% pro-rated (but I believe still covers any potential install costs). It's got 3yrs free then is pro-rated.
- For price or price/warranty, hard to beat a Rural King battery (made by Exide) if you have a Rural King around. I believe they stopped carrying AGM, but the EFB's aren't a bad alternative. Warranties aren't bad - the higher tier ones have longer warranties at very competitive prices. They always have a storewide 10% off on Thanksgiving & Black Friday FYI. Also, if they have an employee on duty who can do it, they'll swap the battery for you. Bonus - no hassle returns. They don't even test batteries you bring in for warranty purposes at our local stores - they just scan them on the computer and pull up your warranty info for the exchange. No hassle at all when I had an early failure on an AGM in our SUV.
- Wal-Mart batteries have a decent rep as a value buy other than that and there is a walmart everywhere. Sam's Club for AGM's isn't horrid (Duracell I think? made by East Penn) - they will sometimes run ~$25 or so off on them, I've seen it around Thanksgiving, but haven't paid close attention since we started shopping Rural King batteries.