EFB Battery Guide: Everything You Need to Know About EFB Technology


Nowadays, motor vehicles come with start-stop systems that are designed to improve fuel economy. The start-stop system does so by limiting the engines idle time. This is made possible by subsequently shutting down and restarting the engine’s internal process.

As a result, it is necessary to have a car battery with improved deep cycle durability for a reduced charge state (which is normal with start-stop systems).

Ideally, most motorists would assume a typical flooded battery would suffice but this is not the case. An EFB battery is required.

If you do not know what this technology entails, keep reading. You will learn about the different battery technologies as well as the features that make EFB special.

What Is An EFB Battery?

EFB stands for Enhanced Flooded Battery. It is typically an improved version of a wet battery.

What a wet battery? A wet battery is a rechargeable battery that contains a liquid electrolyte. For vehicle batteries, the electrolyte used is sulfuric acid. If you are not conversant with battery terminology, kindly have a look at this article for a basic guide to batteries

Depending on which country you live in, this type of battery also goes by the terms Improved Wet-Flooded Battery (IFB) and/or Advanced Flooded Battery.

These batteries come specifically designed as a lower option to the Absorbed Glass Mat (AGM) batteries in terms of durability and output. As a result, EFB often gets mistaken for AGM and standard wet-flooded batteries.

Start-Stop EFB

EFB VS Standard Flooded Battery

Compared to wet-flooded batteries, EFB technology has better performance and durability.

Let’s start by comparing the total number of engine starts each battery can provide before a recharge is required.

On average, EFB batteries provide up to 85,000 engine starts while standard wet-flooded batteries have a max of 30,000 engine starts. By approximation, EFB batteries provide up to 50,000 more engine starts than the standard flooded batteries.

Hence when using a start-stop system, it is evident that an EFB will have a far better duration than standard wet-flooded battery technology.

EFB Vs AGM Batteries

EFB batteries are designed as a mid-tier battery between the lower tier wet-flooded battery technology and the higher tier AGM battery.

In a nutshell, EFB is based on the improvement of flooded battery technology. The improvement consists of additional carbon additives during the manufacturing of the battery plate.

On the other hand, AGM batteries are based on an entirely different design. The AGM design consists of recombinant lid technology, glass mat separators and higher pressure pack. All this provides better cyclic lifespan compared to the Enhanced Flooded Battery technology.

As a result, the AGM battery is better suited for high specification vehicles that have a higher energy demand. The high demand could be as a result of the vehicle having multiple technologies such as passive boosting, regenerative braking as well as start-stop systems altogether.

It is for this reason that EFB batteries are considered the second tier to AMG batteries. The can only suffice for a limited number of high output demanding systems.

Key Features Of EFB Technology

Enhanced flooded batteries have two main characteristics, namely scrim and acid circulator.

The Scrim is a polyester element added between the plate and the separator. Its purpose is to prevent the erosion of mass by holding the reactive material in its place.

This results in an enhanced deep cyclic resistance and a superior charge acceptance.

The acid circulator prevents the stratification of the acid. This modification utilizes the inertial movements of the vehicle to maintain a constant circulation of the acid.

Due to the homogenous density levels of the acid, charge acceptance and overall battery life are improved.

Does the Technology Truly Live Up to Its Reputation?

Well, yes it does.

Enhanced Flooded Technology has become a cost-effective mid-tier option for vehicles that come with entry-level start-stop systems. The technology is also designed to meet OEM vehicle standards and now comes factory fitted in a variety of vehicles with entry-level start-stop technology.

Additionally, emission standards on start-stop vehicles are set lower than high-performance vehicles. Hence, EFB manufacturers have met the demand for batteries that provide a higher state of charge than AGM batteries, while at the same time providing a lower state of charge than entry-level wet-flooded batteries.

Advantages Of EFB Technology

Benefits for Small Vehicles

  • The technology provides two-times the deep-cycling performance and partial state of charge found in conventional batteries.
  • The number of engine starts is higher and so is the extended periods of engine-off time.
  • Compared to regular flooded batteries, the charge acceptance of EFB batteries is better.
  • The technology comes with adequate thermal stability. This makes it perfect for use in hot climates such as Africa and the Middle East.
  • The technology is ideal for a vehicle with start-stop technology minus regenerative braking systems. It is also very efficient for vehicles that have higher than normal energy demands. The demand can result from a tough driving schedule or multiple electronic components installed in the vehicle.

Benefits for Commercial Vehicles

  • The guarantee of a high cyclic ability due to the improved grip-to-mass adhesion and positive paste.
  • Very low water consumption due to the unique lid design.
  • Optimum performance guarantee due to high vibration resistance, and best-in-class hot melt.
  • The extra carbon addition to the plate reduces the stratification of the acid. This provides an optimal solution for deep discharge solutions.

FAQs About EFB

Can an EFB Be Tested with a Regularly flooded Battery Tester?

For some, yes. However, most EFB batteries will test inaccurately with the standard flooded test algorithms. This will lead to a misdiagnosis of the battery due to over-reading the CCA value.

Will the EFB Battery Freeze If I store It in the Garage During Winter?

Provided the battery is kept in a charged state, you have nothing to worry about.

Final Verdict On EFB Technology

The technology is designed to bridge the gap between standard flooded batteries and AGM batteries. Its mid-tier capabilities make is suitable for vehicles that operate start-stop systems because they require Cyclic durability.

Additionally, the technology comes with adequate thermal stability which is ideal for hot temperate regions such as Africa, The Middle East and Asia.

As a final point on this article, it is essential to confirm that your vehicle uses EFB battery before replacing it. If you have a start-stop system it is likely that you have an EFB under the hood.

We appreciate you taking the time to read about EFB battery technology and we hope you have gained some insight on the topic.

For more information on battery products and maintenance tips, please visit our website and let us cater to all your battery needs.

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