I have a 2021 I bought just about a year ago. I had the dealer add lights and heater, stereo, wiper, etc. Mine has turned over slower than I would expect from early on. Was really surprised to find non-watertight connections in Ignition system wiring in multiple places. As my lights have started to quit working, I have torn into the whole wiring nightmare done by the "Honda Dealer" in Casper Wyoming. Not only did their guy commit several wiring sins, but Honda did a really poor job of protecting the connections from moisture, resulting in widespread corrosion at connection points. I replaced batteries figuring that was the problem at first before I really looked deeper, but it still didn't fix problem so I have been digging deeper. Many connections were corroded, and each poor connection causes resistance and voltage drop. Be sure your grounds are "Clean & Tight" all the way back to the main ones on the engine case. I use "Kopr-Shield" on all my connections as I clean them up. It will increase the electrical connectivity and reduce any future corrosion.
As for batteries, a good rule of thumb is that more lead of a higher quality will allow for more of the chemical reaction necessary to release the energy we want to see from our batteries. More lead weighs more, costs more, so if you buy a Chinese made battery of recycled lead from Harbor Feint, it won't give you the same power as a quality virgin lead battery that weighs much more in the same battery case size. Batteries are a consumable product and every charge discharge cycle causes molecules of the lead to flake off and settle in the bottom of the battery case, so more lead equals longer battery life. Also, don't let batteries get deeply discharged because that causes sulfation on the plates, and the deeper they go the more sulfation they get and it doesn't come off completely.
Just my .02 worth.
www.harborfreight.com
