For the average punter, your car battery might seem like a simple box under the hood that gets things started, but there's more to it than meets the eye. Did you know there are two main types of car batteries available: AGM and flooded. Understanding the critical differences between these two battery technologies can help you choose the correct battery for your vehicle's needs when it comes time for a replacement battery.
How are AGM batteries different from flooded batteries in their construction?
Flooded Battery
This traditional battery features lead plates submerged in a liquid of sulfuric acid electrolyte. Separators keep the plates from touching, and vent caps allow gas to release during charging. Flooded batteries often require an upright position to maintain proper electrolyte level.
AGM Battery
A newer innovation, AGM batteries use a fibreglass mat saturated with electrolytes, which surrounds the lead plates. This sealed design eliminates the need for liquid top-ups and allows for more flexible mounting positions in your vehicle.
Maintaining flooded batteries vs AGM batteries – what’s the difference?
Flooded Battery
Flooded batteries will require a little more regular TLC than their AGM counterparts. You'll need to check the electrolyte level every few months and top it up with distilled water if needed. Additionally, corrosion buildup on the terminals is a common concern, meaning you may need to occasionally clean the terminals.
AGM Battery
Here's where things get easier when it comes to maintenance. AGM batteries are virtually maintenance-free. The sealed design minimises corrosion, and there's no need to check or add electrolytes on a regular basis. So whilst AGM batteries may cost you a little extra, they reduce the need for regular maintenance.
Battery performance: Starting Strong and Lasting Long
Not all car batteries are created equal! When it comes to performance, there's a pretty clear line between AGM and flooded batteries. AGM batteries give much better cranking power for starts, especially in cold weather. They also handle deep discharges better and recharge faster, which means they’re ideal for vehicles with stop-start technology or those that use onboard electronics.
Flooded batteries, while still a solid option for some, may struggle with these demands. Let's delve deeper into the specific advantages of each type to help you choose the battery that best suits your driving needs.
Starting power
AGM batteries will usually boast higher Cold Cranking Amps (CCA), which translates to better starting performance in cold weather or for engines that need a little more cranking power.
Deep discharge
If you regularly take deep discharges from your battery (like using car electronics for extended periods with the engine off), AGM batteries are going to be your best bet. They can handle deeper discharges and recover better than flooded batteries.
Recharge cycle
AGM batteries can generally recharge much faster than flooded batteries.
Vibration resistance
Hitting the rough roads and out of the way tracks? AGM batteries are champions of vibration resistance due to the absorbed electrolyte within the fibreglass mat in their internals. Flooded batteries – particularly those with low electrolyte levels, can be more susceptible to vibration damage when things get a little rough.
What about safety?
AGM batteries have a sealed design that helps prevent leaks of acid or flammable gas emissions. This helps reduce corrosion and also reduces the chance of an explosion when compared to flooded batteries. For drivers concerned about passenger safety and overall peace of mind, AGM batteries offer a clear advantage.
AGM battery
The sealed design of AGM batteries prevents leaks of acid or gas emissions, making them a safer choice for passenger compartments or enclosed areas. They also pose a lower risk of explosion due to gas buildup.
Flooded battery
Flooded batteries vent hydrogen gas, which is flammable and requires proper ventilation to avoid potential explosions. Additionally, if the battery casing cracks or breaks, there's a risk of acid spills.
Which battery lasts longer – flooded batteries or AGM batteries?
The simple answer is that AGM batteries will generally last much longer than flooded batteries - here’s why.
AGM battery
Generally, AGM batteries offer a longer lifespan (sometimes even double) compared to flooded batteries, especially with proper use. This is mainly due to:-
- Reduced sulfation
- Minimised water loss
- Vibration resistance
- Deep discharge tolerance
- Sealed design
Flooded battery
The lifespan of a flooded battery depends on maintenance and usage patterns. Frequent deep discharges or high operating temperatures can shorten the life of flooded batteries.
Cost considerations: Balancing price and performance
It’s no secret that AGM batteries typically cost more than flooded batteries, but there’s a very good reason for this.
AGM batteries typically have a higher upfront cost due to their advanced technology and features, plus they also tend to last a lot longer than flooded batteries.
Whilst flooded batteries are the more affordable option, you need to remember to factor in the ongoing maintenance costs like distilled water and potentially more frequent replacements.
Choosing the right battery for your ride
AGM Batteries are the perfect choice for newer vehicles with stop-start technology as they can handle frequent deep discharges and fast recharges. Also, their durability and vibration resistance makes them great for high-performance engines, motorcycles, sports vehicles and off-road applications. They're also a much safer option for passenger compartments.
Flooded Batteries are suitable for older vehicles with conventional starting systems and minimal electronics. They're also the more budget-friendly option, which is why people like them.
Choosing the correct battery for your car doesn't have to be a painstaking experience. By understanding the differences between AGM and flooded batteries, you can figure out which battery best suits your vehicle. If you still need advice on a replacement battery for your vehicle, visit one of our stores or contact us today to find the perfect battery for your needs!
