Most fashionable autos on the highway within the US are geared up with Absorbed Glass Mat (AGM) batteries, which have lengthy been accepted because the go-to choice for start-stop fashions. The best battery expertise is crucial for powering battery-draining autos with options comparable to infotainment methods, voice recognition capabilities and anti-theft methods. There’s a newcomer on the town, nevertheless, that threatens AGM’s place within the US market: Enhanced Flooded Batteries (EFBs). New analysis exhibits that EFB expertise surpasses AGM in vital areas together with battery life and warmth tolerance, amongst others.
If AGM batteries appear to be working simply superb, why ought to automotive producers care? EFB expertise is reasonably priced. Coupled with higher efficiency, affordability is more likely to make all of the distinction sooner or later.
Classes from Europe
Whereas newer to the US market, EFB has been in Europe since 2008. The US automotive business basically tends to observe Europe by about ten years, a sample which appears to be like to be repeatable for EFB. In Europe, there may be an roughly 50/50 cut up between AGM and EFB for powering start-stop autos, nevertheless it didn’t begin out that method. Europe used to closely depend on AGM however as the advantages of EFB have been more and more realised, it gained floor.
Not solely did EFB match AGM efficiency in a number of key areas, nevertheless it additionally outperformed the expertise when it comes to battery life, warmth tolerance and mid-depth biking resilience
In distinction, AGM’s dominance in North America comes courtesy of its early backing by a number of vital proponents. Clarios, previously Johnson Controls, for example, devoted US$245m again in 2016 to double its AGM manufacturing capability by 2020. It projected on the time that round 50% of vehicles in North America would have a start-stop system by that date. This enthusiasm and heavy adoption imply it’s now far and away the principle battery utilized in start-stop autos within the US right this moment.
Nevertheless, a analysis research commissioned by Stryten Manufacturing and carried out by an unbiased third-party analysis firm and battery testing lab suggests AGM’s dominance is underneath risk. Not solely did EFB match AGM efficiency in a number of key areas, nevertheless it additionally outperformed the expertise when it comes to battery life, warmth tolerance and mid-depth biking resilience.
Face to face
Battery returns within the US are monitored each 5 years to find out why batteries exit of service. Between 1965 and 2010, the typical battery life span elevated yearly. Then, between 2010 and 2015, battery life began declining. Previously 5 years, the US market noticed a 30% enhance in battery failure with biking, brought on by the rising inclusion of further digital options in cars.
To measure mid-depth biking resilience, the research included a 17.5% Depth of Discharge Check, which is the business normal for characterising the power of a battery to function underneath a partial state-of-charge software. This take a look at is just not solely a easy measure of a battery’s mid-depth biking functionality, however can also be designed to emphasize the cycle-to-cycle recharge functionality of the battery. Partial state-of-charge operation is widespread in stop-start functions. On this take a look at, over an 18-week interval, the whole common capability output of EFB was 50% better than AGM for an equally-sized battery. This means that EFB not solely can yield as many cycles as AGM however may maintain its whole capability to the next degree with out decay.

An space the place EFB significantly outperformed AGM was in temperature checks. AGM batteries have traditionally suffered from an absence of thermal stability, which ends up in shorter battery life in excessive temperatures. That is why the US Army has integrated an overcharge-thermal runway take a look at to its AGM take a look at requirement course of. One research confirmed that when this take a look at is run at 50 levels Celsius, an EFB battery was capable of blunt the temperature rise and soak up 52% extra power than a comparable AGM battery. When translated into an operations atmosphere, the implication is that an EFB will final 52% longer than an AGM battery in high-temperature environments.
One other battery characteristic rising in significance is the power to simply accept recharge after a discharge occasion. This can be a measure of how ready the battery will probably be to help the subsequent discharge cycle want. That is presently measured by a take a look at often known as Dynamic Cost Acceptance. Briefly, the take a look at measures a battery’s cost acceptance functionality underneath typical states of operation. In essentially the most demanding section, which is supposed to copy real-world stop-start utilization, EFB yields cost acceptance functionality on par with AGM batteries.
Implications for the longer term
Based mostly on greater than a decade of proof in Europe and this newest research within the US, is EFB nearly as good as AGM? More often than not and within the vital checks that matter for automotive battery efficiency, sure. Is EFB higher than AGM? Typically, sure, however not in each case.
Over an 18-week interval, the whole common capability output of EFB was 50% better than AGM for an equally-sized battery. This means that EFB not solely can yield as many cycles as AGM however may maintain its whole capability to the next degree with out decay.
If the outcomes are comparable, why would the US automotive business undergo the difficulty to change from AGM to EFB? That’s the million-dollar query, and the reply is value plus efficiency. AGM continues to be the selection for powering deep cycle wants, which is a distinct segment use of an automotive battery. Nevertheless, for almost all of shoppers, EFB presents a greater, longer-lasting battery for the circumstances they’re most definitely to come across whereas driving, comparable to battery life, warmth tolerance and mid-depth biking resilience. EFB offers a greater shopper expertise in comparison with AGM which is a major differentiator and it offers a aggressive benefit for gamers within the US automotive business that embrace EFB expertise.
It’s too quickly to inform what expertise will win the US automotive battery battle, however one factor is for certain: this could possibly be an actual game-changer.
John Miller is Senior Director, Product Improvement at Stryten Manufacturing.