Are these numbers on the battery terminal and tyre inflation compressor (10/16) dates of manufacturing ? How long does a battery last? I didn't use the car for 4 days and the battery went down to the point that the engine wouldn't turn over. The car was delivered to me on June 27th 2016, so i can't understand how its fitted with a battery and compressor from October 2016 if the numbers are indeed manufacturing dates as i suspect. Unless they were changed during service.