Drivers are paying more than they have to for replacement car batteries because they don’t realise that cars featuring eco technology need specialist equipment. Frequently, cheap batteries bought for start-stop cars then fail relatively swiftly because they aren’t up to the job they’ve been bought for.
Nearly two thirds (60 per cent) of the cars sold in Europe now have either start-stop or energy recuperation technology. This is where the engine automatically shuts down when the car comes to a rest. It then fires up again as soon as the driver dips the clutch, or in an automatic, releases the foot brake. Start-stop is estimated to cut fuel use by between five and 10 per cent. Energy recuperation harvests the kinetic energy that’s usually wasted as a car slows down.
But in order for these smart technologies to work, cars need to have special batteries. These Absorbent Glass Mat (AGM) and Enhanced Flooded Batteries (EFB) last longer than regular lead acid cells. This is because they’re designed to retain sufficient charge to be strong enough to power a car’s various electrical systems such as the windscreen wipers, ventilation and sound system while the engine is turned off.
Spares company Euro Car Parts has reported a 100 per cent year-on-year increase over the first three months of 2016 in sales of AGM and EFB batteries. But it warned that some drivers ignore their car’s requirement for a special battery. Company CEO Martin Gray said: “It is no longer a case of any old battery will do. It’s about choosing the right battery. If you fit an incorrect battery to a car with start-stop, it might work initially but certain systems will soon begin to fail, starting with things like the radio, air con and electric windows, and then more vital systems, such as the start-stop function itself.”
Understandably, drivers are being tempted to choose cheaper batteries by the difference in price between regular and start-stop batteries. A battery for a Volkswagen Golf-size car without start-stop will cost £85 including a four-year guarantee, from motor retailer Halfords. However, an AGM battery for the same size car will cost £149. And it will cost around £15 more to fit an AGM battery compared to the less sophisticated sort. While the majority of batteries are guaranteed for four years and can go on to last between five and seven years, a regular battery that’s fitted to a car needing an AGM type may struggle to outlast its guarantee.
Find out if your car needs a special battery by looking in the handbook. This should give the exact specification of battery that it needs.