The RAC is warning drivers to make sure their first day back in work after the Christmas break is not a case of what it has coined the ‘flat battery blues’ on ‘back to reality day’. It says the first day of the first working week after New Year is “notorious” for vehicle breakdowns. That’s because thousands of cars have been left idle over the holiday period, leading to older, weaker batteries slowly draining to zero and failing. The RAC says it is expected to be especially problematic this year given colder temperatures which will “test the chemical reaction of car batteries to the limit.” RAC mobile servicing and repairs team leader Nick Mullender said: “A flat battery at the start of the new year is more than enough to drain away the last of the Christmas spirit. “If you’re one of the millions of drivers taking to the roads on Monday, make sure you’ve given your car a really good run in the days beforehand, even if it’s just to fill up with fuel. …