Yesterday I purchased a brand new, maintenance-free, 12 volt lead acid car battery. Specs: 47Ah and 450CCA.
Before I install it in my car, I measured the voltage with a catIII digital multimeter. It read only 12.33v. With the engine running, the reading is 14.2v (so the alternator works fine). After a 30min drive, the voltage was 12.72v right after I shut off the engine. After 8 hours sitting, the voltage was 12.38v.
Could this brand new battery be defective? The manufacturing date is OCT 2019 so for sure it must have been sitting on the shelf for quite a while. I also know that my car's drain is about 39mA-40mA.
What is the minimum voltage reading for a typical brand new battery?