According to the U.S. Department of Transportation, the average American driver drives 13,474 miles per year. I drive a lot more than that.
The OEM battery gave me 170k miles.
In other terms, my OEM battery gave me 12.6 years of service based on how many miles the average American drives in a year.
My Walmart battery lasted 80k miles, which translates into 5.93 years of service.
Not too shabby for a low quality battery.
I asked about this and the answer is no. My two year warranty started when I purchased the original battery and ends two years after that date, regardless of how many replacements I have.
Think of it as a service contract or extended warranty. The contract doesn't reset every time you have service done. If it did, you could potentially have a lifetime warranty every time something broke.
Of course, consumer laws certainly can vary from state to state. I'm just telling you how it is at my local Walmart. I would imagine consumer protection laws are much different in places like California.