Battery Tester for AGM Battery

Well, here I am.  I'm reading that you can't use a carbon pile tester on an AGM battery and that's the exact combination I have.  Brilliant!

So, I'm wondering if anyone has an opinion about digital battery testers.  Are they just commodities and you'd buy the cheapest one or do ya cough up a few more bucks for something like a Topdon?   amzn.to/45orU0m

(I'm waiting for the charger to do its thing right now but even if this isn't something that requires a test of the battery, I believe the day will come.  And I assume they want some kind of proof that the battery is bad before they just hand you a brand new one.)

I'm reading that you can't use a carbon pile tester on an AGM battery and that's the exact combination I have.  Brilliant!

I've heard the same! But can't recall if there was an actual reason why.   If you've run into any actual reasoning or documentation on that, I'd love to see it.

My experience is exactly the opposite - You can and SHOULD use carbon pile testers on AGM batteries. I've come across many AGM/EFB batteries that miserably fail a carbon pile test, but capacitance testers swear up and down are 'OK'. New battery fixes it.

So, I'm wondering if anyone has an opinion about digital battery testers.  Are they just commodities and you'd buy the cheapest one or do ya cough up a few more bucks for something like a Topdon?    amzn.to/45orU0m

My coworker has that tester and likes it. We've compared it to the Launch tester I have, and the results are very similar.

www.amazon.com/Launch-Bluetooth-Charging...ycles/dp/B093Q33NVW/

I'm generally pretty happy with the performance you get at the ~$50 price point. Less than that and I'd have trouble having confidence in the results. 

(I'm waiting for the charger to do its thing right now but even if this isn't something that requires a test of the battery, I believe the day will come.  And I assume they want some kind of proof that the battery is bad before they just hand you a brand new one.)

You're talking about warrantying out the battery? Where'd you buy it from?

How much proof they want will depend on the retailer and who's behind the counter at the time.   Most big box retailers or parts jobbers won't ask too many questions, in my experience.