The temperature outside affects the voltage of the battery. Remember that category iii is up to a 1,000 volts, category ii is up to 600.
I think for a 12v dc battery (you mean like a car battery?) you can measure the voltage, and with certain battery chargers it can tell you more, but otherwise you are going to need more than a multimeter to measure the amps.
Car battery amps multimeter. You can also use a digital multimeter to check your battery’s current power. Note battery voltage with the engine off. Depending on the model they provide the user with the live voltage reading through a set of led’s, on a digital display or with the more advanced versions via bluetooth direct to your smartphone.