AGM batteries – the best choice for start-stop vehicles

EFBs lag in performance, durability.

OEMs in the U.S. are rapidly introducing start-stop technology to reduce CO2 emissions and increase miles per gallon. In fact, by 2025, nearly 20 percent of cars on the road are expected to be start-stop vehicles. And to power these vehicles, along with their ever-growing electrical load, OEMs are selecting absorbent glass mat (AGM) batteries over EFB (enhanced flooded batteries).EFBs lag in performance, durability

Clarios lab and fleet tests show AGM batteries deliver double the cycling performance and corrosion resistance compared to EFB. In start-stop applications, EFBs lost six times more water and lost 60% more capacity than AGM batteries, signaling increased warranty claims and reduced consumer satisfaction.

What’s more, Clarios AGM batteries can support nearly 90 percent of U.S. vehicles that have high electrical loads, including all start-stop vehicles. OEMs have embraced AGM technology for its reliability and durability, to the point where the number of vehicles in the market using AGM batteries will nearly triple by 2025. 

While standard flooded batteries and EFBs do offer some benefits, they miss the mark in the following key areas.

Performance. Today’s start-stop vehicles require a battery that can deliver power during the engine-off sequence—and at the same time, power everything from the latest safety features to infotainment systems during engine-on. EFBs lag in performance for power-hungry vehicles; they were designed for low to medium start-stop vehicle functionality, and never intended for conventional vehicles. AGM batteries, on the other hand, are designed to handle all start-stop applications as well as conventional applications, including those with the highest demands, recovering (recharging) quickly from low charge conditions for reliable operation again and again.

Service life. Market research shows battery failure is now the third most commonly reported new vehicle problem—and the 10 models with the highest battery replacement rates all used a flooded battery. An AGM battery, however, stands tough in the most demanding conditions. Clarios AGM batteries feature a proprietary valve and unique AGM separator to resist breakdown and help ensure water regeneration, extending service life in high heat.

Warranty claims. When an EFB is used to replace an AGM battery, acid stratification can cause the vehicle’s battery management system to misread the state of charge, giving a false positive.

Safety. An AGM battery’s non-spillable design gives automakers the flexibility to place the battery in a wheel well, under the passenger compartment, or in the vehicle’s trunk. Replacing AGM batteries with EFBs in these locations introduces a clear safety risk: an accident could result in EFB acid leaks, spills or worse. AGM offers consumers the greatest peace of mind that the battery in their vehicle is safe.

As a global leader in energy storage, powering 1 in 3 of the world’s vehicles, Clarios has in-depth knowledge of battery design, gained from rigorous lab and fleet testing as well as extensive in-market experience. Engineered with that expertise, Clarios AGM batteries consistently outperform EFBs. AGM batteries are the right solution for start-stop and high electrical load vehicles—powering today, into tomorrow.