Originally Posted by grim_reaper

CX-5 with i-stop needs a Q85 EFB, 650 CCA

Originally Posted by Callisto

Depends on what you are willing to do to maintain the health of the battery. Even in the best conditions without a trickle charger frequently used to maintain 13-13.5 volts constant all automotive battery will start a slow decline. Also, without the consideration to add larger or a few more batter cables the factory MAZDA cables are not the best size in the long term.
I would at least add a couple or more grounds and addition large single cable from the battery to the starter. The starter has the greatest load effect and naturally some of us it several times a day.


If not willing to do these suggestions, then.... by using the same battery load tester (load tester that show test voltage before, during and after in at least the tenth scale better 100 scale) and the exact same setting, make sure to get the temperature of the engine compart and better the battery at the time of the teat, log the results, repeat every 2 months and you WILL see if the battery is starting to decline.

Originally Posted by chickdr19

And that is just it. So much variation. In some of my cars I have used a NOCO trickle charger from time to time to top up the battery. With the current CX-5 I have done nothing so far. My 2020 Nissan Frontier is now 37mths old. Still the OEM battery as well with no maintenance done and running strong. My 06 Z4M sits unused most of the time and needs charging monthly to stay in shape. Battery seems to die every 4-5yrs with the monthly charging.