CALCIUM, EFB OR AGM?
R&J Batteries tries to answer the question of ‘which one you should choose’

The automotive industry is known for its complexity, and the aftermarket sector is no different.
Customers are often overwhelmed by the abundance of choices available.
The automotive battery category alone has various options for customers to consider based on power requirements, budget and lifestyle needs.
The three main types of automotive batteries commonly available are Maintenance Free (Calcium), Enhanced Flooded Battery (EFB) and Absorbent Glass Mat (AGM) batteries.
It is imperative to understand the key differences between these types to understand which battery is right for your vehicle.
Calcium batteries are the most widely used among the three.
These lead acid batteries have small amounts of calcium added to the positive and negative grids which enhances grid durability.
Calcium batteries are called maintenance free because the water in the electrolyte doesn’t evaporate like it does in conventional lead acid batteries, which eliminates the need for regular maintenance to top up (replace) the water.
EFB batteries are a mid-range option which are relatively new to the market and have been specifically designed to meet the needs of modern Idle Stop Start (ISS) vehicles.
Built on the Calcium battery design, EFB batteries benefit from improvements which increase charge acceptance, cranking power and the ability to constantly function at a Partial State of Charge (PSoC).
EFBs are considered to be an entry level option for vehicles with ISS technology.
R&J Batteries say AGM batteries are the ultimate choice for premium and prestige vehicles, including those fitted with ISS systems.
AGM batteries differ from flooded batteries in several ways, though the basic chemical reaction remains the same.
They use a compressible glass mat to separate the positive and negative plates; these glass mats also absorb and suspend the electrolyte needed for the battery to function.
This design improves durability and resistance to vibration, resulting in a longer service life when compared to Calcium and EFB batteries.
AGM batteries are well suited to vehicles with high accessory and technology demands, as well as those with ISS systems to help save fuel.
In terms of cost, AGM batteries are more expensive than Calcium and EFB batteries because they are more complex to manufacture.
While it is possible to upgrade a battery to a higher construction type, downgrading is never advisable, says R&J Batteries.
A vehicle initially fitted with a Calcium battery can almost always be upgraded to an EFB if the case size matches.
Downgrading from an EFB battery to a Calcium battery however will lead to premature failure.
The installation environment also plays a crucial role, particularly in terms of temperature.
Flooded batteries are better at managing heat compared to AGM batteries, as the electrolyte helps transfer heat to the outside of the case.
It is also sometimes possible for ISS vehicles to upgrade from an EFB to an AGM, depending on the battery location and the charging system of the vehicle.
If the original battery had a heat shield installed, it must always be installed around the replacement battery as this reduces the heat transferred to the battery which extends battery life.
R&J Batteries is a leading distributor of batteries in Australia with 24 branches across the nation and a wide network of more than 18,000 stockists.
Its comprehensive automotive battery range includes Calcium, EFB and AGM batteries from brands such as ACDelco, Delkor, Predator, Koba, Optima, Fullriver, and more.
For more information, visit www.rjbatt.com.au or visit your local R&J Batteries branch.