This post is for my 2021 Mazda 3 but I want to comment on my wife’s 2018 CX 5 to bring context to this post:
About a year ago, I was surprised that the CX5 was down on cold cranking power to the starter. I looked under the hood, removed the battery hold down to notice the fluid level in the battery was low (There is a cover over the battery so it’s difficult to check the battery fluid level). I always had assumed that the car had a sealed battery, which is not the case. I added distilled water to proper levels and used a quality trickle charger that claims to remove contamination from the internal plates. Anyways, the battery is still low on power but works well enough to consistently start the car.
Now, to my own car, 2021 Mazda 3. I have the same concerns with the my battery. Does anyone know if maintenance is required on the factory battery. Hoping to catch any issues before they happen. Car is 2.5 years old. Thanks!

 

Batteries should health checked every season beginning. That means at least load tested.
Anything beyond that would depend on who did the load test and their experience with looking at possible issues?
I do recommend not to go by what your batteries birthdate or guessed manufactured age is and go only by what the results of the load test are.

 

Ok thanks.
Do you know if I have a sealed or a serviceable battery on the 2021 Mazda 3 ?

 

I don't assume anything when it comes to what anyone got, should have gotten or have with their new MAZDA.
The dealer may have replaced it which is not uncommon.

 

Concerning batteries:
To my surprise I discovered that the battery fitted to my April 2023 delivery Mazda Astina is a liquid cell type,
not a sealed battery which I have always assumed is the superior type now fitted to all vehicles, because they do not emit acid fumes, and the acid level/quantity is maintained constant. (no maintenance)
However I am given to understand that the liquid cell batteries are able to provide a larger discharge current when starting a cold engine. But the acid level must be maintained in these batteries otherwise the cells will degrade
and cranking power greatly reduced.
My guess would be that Mazda fit a liquid cell battery to their vehicles because they are fitted with "Idle Stop"
and therefor the battery is in far greater usage, for those who do not cancel this silly and doubtful feature.

 

I see that my explanatory theoretical post on how to regard the internal resistance of a battery
has been removed.
I guess it has been removed at the request of someone here!!
So also has the amusing image of callisto's engine bay showing a jar of VEGEMITE

 

Battery type fitted to MAZDA was Soley based on bean counter in MAZDA corp. There is a good article about this from MAZDA. Go find it and read it.
I would recommend that you do not post grievances about any edited or removed posts from you or other members on really any forum. This is another thing you just don't do and you will learn as I understand you are new to posting on forum and don't know all the basic responding etiquette yet?

I did report you last response and also my own.

BTW the picture and response with the vegemite was to break the ice and make posting between use a little more positive not in any way negative. If you saw the smiling emo? But again I do understand you don't get the forum specifically car atmosphere of posting. But then this forum is the same as my EMT , photography, road bike, BMX Bike, motorcycle, quantum physics, diving , vegan ,etc., and few other subject forum based there is always a a nebie that post like you and there is always members that don't get along perfectly. LIVE WITH IT! LOL

 

TIME: better to spend it 'building everyone up', than tearing one down. Never ceases to amaze me that some poster's can get so cranky...
BATTERYs: plus one on the Bean Counters causing so many Issues for vehicle owners... sooner or later. AGM (advanced glass mat) batterys can have similar CCA (cold cranking amperes 'output') as the good-old Lead-Acid batterys. AGM's advantage is that 'particles' from the Plates do-not fall down into the bottom of the Case, and build up atop each other until the plates get shorted... as-much-as occurs with the Lead-Acid designs. [Why AGM batterys are used by smart MotorCyclists that enjoy more road 'bounce' than cars.]
When MFGs purchase large batches of Batterys (or any other part), they want cheapest-per-unit Cost, versus "projected possible Warranty Claims costs". The actual Engineers will test Parts, find out which will last and/or likely cause problems for Vehicle Owners down-the-road... and debate with the Bean Counters at the 'production roundtable' Meetings. Guess who gets the Bonus at year-end?

 

I smile almost all day long when I log on to forums. Very rarely EVER I pound the keyboard like I know some of my forums mates/members often do when or some other members respond to some of their internet found wisdom. LOL
As I try to often to suggest members and mostly NEW MEMBERS on forums before you start to debate with any member especially a long time veteran member of a forum with hundreds or thousands of postings it is better to find out about them. Look at what, when and where they post their responses and what kind of information they post. Not all of us are DIY and some members are actual long time experienced ,trained and educated in many fields of the automotive industry!

That said your response:
Not exactly sure where you got this information, but it is not really how it works about batteries with auto manufactures. The biggest item is you give to much credit to the bean counters and the engineers on this specific part. Maybe next time research a couple auto manufactures to find better information and good luck with them supping any information! When and if you do than you will understand why I posted this response!
I might add that you are way off with the information about Motorcycle batteries and Motorcycle manufactures. This information is fairly easy to find if you word it correctly on the internet. But you must contact or use specifc Motorcycle manufactures. Example HD uses bot wet and dry batteries in most of the models they offer in the US but those same models in other countries only a dry battery. The same with AGM vs wet depemding on where the sales and exporting of the Motorcycle is done.

If I did not when you joined... WELCOME TO THE FORUM

 

unless you do a LOT of longer trips using a good charger like the C-Tek i use will make your batteries last longer!! all my vehicles have older batteries + doing fine because they get a charge from my C-Tek charger regularly, my oldest battery is OE in a 13 Victory motorcycle!!