AGM Batteries Compared. Lead Acid Batteries

Your car’s starting battery is likely one of two rechargeable types: flooded lead acid or AGM.

But how do these two batteries vary from one another?

This essay will compare AGM versus lead acid batteries and see how they differ.

Let’s get started.

5 Key Differences Between AGM and Lead Acid Batteries

Before we get started, it’s worth noting that the AGM battery has its roots in the classic lead acid battery. As a result, they do have some parallels.

Let’s compare each battery kind, starting with its inner workings.

1. The Difference Between AGM and Lead Acid Batteries

When it comes to their base chemistry, AGM batteries and ordinary lead acid batteries are identical. Both employ lead plates, an electrolyte mixture of sulfuric acid and water, and a chemical process that creates hydrogen and oxygen as a byproduct.

This is when they begin to differ.

Here’s how it’s done:

A. Lead Acid Flooded Battery

FLA battery works by immersing lead plates in liquid electrolytes. The gases created by the chemical reaction are released into the atmosphere, resulting in water loss. As a result, electrolyte levels must be replenished regularly.

B. AGM Battery

AGM batteries are made up of fiberglass matting placed between lead plates. From this, the battery derives its name – Absorbent Glass Mat (AGM). The glass mat wicks the electrolyte solution, keeping it suspended and preventing it from flowing freely.

Because the AGM battery is encapsulated, there is little to no off-gassing.

The electrolyte was recombined with gases created during the chemical process.

If there is too much gas (like when the battery is overcharged), a vent lets it out to maintain internal pressure.

2. Maintenance Requirements

Because there is no off-gassing save for the occasional venting, the AGM battery requires no maintenance and may be installed in more confined spaces. It’s ideal for use in vehicles with batteries in trunks and beneath seats and in situations where care is complex.

On the other hand, the flooded battery requires frequent electrolyte service and must be kept in a well-ventilated place since it emits fumes and steam.

3. Durability, Vibration Resistance, and Shock Resistance

Because it was initially designed for military and aviation applications, AGM batteries are often stronger than flooded lead acid batteries.

The AGM battery’s sandwiched construction of glass mat and battery plates results in components that do not easily come apart. This arrangement produces a battery resistant to stress and vibration, making them popular in race vehicles and motorbikes.

Forceful movements and heavy vibrations can damage flooded battery plates; therefore, they must be firmly attached to limit these effects.

4. Mounting Spillage And Flexibility

The AGM battery’s glass mat technology makes it spill-proof and position insensitive. You may mount it in various ways (don’t turn it upside down).

However, because the flooded cell battery contains a liquid electrolyte, it must be kept upright to avoid leaks. If spilled electrolyte is not cleaned up, it can cause corrosion.

5. Power Output and Internal Resistance

The internal resistance of an AGM battery is among the lowest of any lead acid battery. While a fresh flooded lead acid battery may have an internal resistance of 10-15%, a new AGM battery may have as little as 2%.

Low internal resistance means higher battery voltage output.

It also implies less heat loss as electricity cycles through the system.

AGM batteries are more responsive to loading than flooded lead acid or gel batteries. They tolerate high power demands so well that they are the lead acid choice for start-stop cars.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s