Lead acid battery

Lead Acid Vs Agm Battery

Here, we’ll uncover the pros and cons of Lead Acid and AGM batteries.


Lead Acid and AGM batteries are commonly used in cars, industrial settings and recreation activities. Although they have the same purpose, storing energy and providing power, they have different chemistries. We will go over the lead-acid battery and how it compares to AGM. We’ll look at capacity, cycle life, safety, charging requirements, power delivery, charge retention and more. Comparing their strengths and weaknesses allows us to make informed decisions about which battery to use.

History of Lead Acid and AGM Batteries

Lead Acid and AGM batteries have been around for a long time. Lead Acid was invented in 1859 by French physicist Gaston Plante. It became the standard for powering cars, trucks, boats, motorcycles and lawn mowers.

AGM (Absorbed Glass Mat) technology was developed in 1970s Germany for military applications. Both battery types are still popular.

Lead Acid batteries have two lead plates made of lead oxide grids wound together. A sulfuric acid and water electrolyte solution is between the plates. When charge is applied, electrons split and form a current.

AGM batteries also use sulfuric acid, but a different setup. The electrodes are kept in close contact with an absorbent glass mat. This keeps maintenance low and prevents spillage or gas release if the battery is overcharged.

  • AGM batteries are safer and better at deep cycling than other car batteries. They can also handle extreme temperatures.
  • They can be recharged up to 7000 times, making them great for travel or off-the-grid projects. They also offer fast charging times.

Construction of Lead Acid and AGM Batteries

Lead acid and AGM batteries are similar. They both use lead plates and electrolyte solution to create electricity. However, the way they are constructed differs dramatically.

  • Lead Acid Batteries: include lead plates that are immersed in a mostly sulfuric acid-based electrolyte liquid. The battery’s casing has grids or cells which separate the electrodes. When these cells are connected in series or parallel, they react chemically to either charge or discharge the battery’s charge.
  • Absorbed Glass Mat (AGM) Batteries: use moisture-absorbent fiberglass mats instead of liquid electrolytes. They are sealed, so oxygen cannot come into contact with the chemicals. This allows for a more efficient energy storage system, with a longer shelf life compared to lead acid batteries. AGM’s need less maintenance since they are spill-proof and don’t generate gasses during charging cycles. Plus, since no liquid is used, these batteries can be installed at any angle without risk of leaking.

Both batteries offer unique benefits when it comes to power and efficiency. Knowing how they work will help you decide which one is best for you.

Advantages and Disadvantages of Lead Acid and AGM Batteries

Lead acid batteries offer a great cost-capacity balance. However, they need more maintenance as they can lose water over time. Also, they have high thermal performance, better cycle life performance and can be discharged deeply. These features make them popular for many applications.

Advantages of Lead Acid Batteries:

  • Low Cost than AGM batteries
  • Easy to service
  • High starting power
  • Good cycle life performance

Disadvantages of Lead Acid Batteries:

  • Heavier than AGM batteries
  • Poor thermal performance
  • Prone to acid leakage if not installed correctly

AGM (Absorbed Glass Mat) batteries are lead acid batteries with superior thermal properties, deep discharge capabilities and longer shelf life. They use AGM material, making them heavier than wet cell lead acid batteries, and also a sealed unit. They emit less gas during charging. This makes them suitable for enclosed spaces, such as vehicles, boats or devices that may be affected by shock or vibration, as they won’t leak like conventional trickle charge wet cells.

Advantages of AGM Batteries:

  • High Starting Power & Deep Discharge Resistance
  • Better Cycle Life Performance & Shelf Life than Wet Cell Lead Acids
  • Reduced Risk of Gas & Vapour Emission during Charging

Disadvantages of AGM Batteries:

  • Limited Availability in Larger Capacities
  • Higher Cost Than Wet Cell Lead Acid Battery Designs

Applications of Lead Acid and AGM Batteries

Lead acid and AGM (Absorbed Glass Mat) batteries are two of the most commonplace rechargeables. They are used in a range of applications, including alarms, emergency lighting, RVs, golf carts and solar energy installations.

Lead acid batteries have several pluses. They have higher cycle life and peak amp draw capabilities and are cheaper when compared to similarly sized AGMs. Additionally, they are more robust due to their construction – heavy-duty positive plates suspended by neoprene spacers. The downside is that they must be often checked for moisture content as they have open cell tops.

AGMs are newer tech than lead acid. They utilise an absorbent glass mat separator between plates, allowing for a powerful output. They are also maintenance free as they have sealed compartments and high cycling capability – making them perfect for RV or golf cart applications that require start-stop usage. They do come with a cost premium, but the optimised internal design makes them worth it in the long run, as they need replacing less often.

Cost Comparison of Lead Acid and AGM Batteries

Lead acid and AGM batteries are both popular stored energy sources for homes, businesses, vehicles, and entertainment systems. To decide which type is best, compare cost, life expectancy, and energy efficiency.

  • Cost: Lead acid batteries are cheaper upfront. They’re usually one-third to one-half the cost of AGM ones. But consider total cost of ownership. Lead acid batteries need more frequent replacements and maintenance, such as topping up with distilled water or replacing lead plates.
  • Life Expectancy: Lead acid batteries can last 4-6 years. AGMs may last 8-10 years, depending on usage. For instance, power sports vehicles and solar off-grid applications draw heavily on battery life. On the other hand, cars and remotes draw small amounts, so AGMs last longer.
  • Energy Efficiency: Lead acid batteries need higher charging currents than AGMs. Tests have found that AGMs deliver 2-4% more energy when calculating amp/hour capacity. This means they are slightly more efficient per KWh.

Maintenance of Lead Acid and AGM Batteries

Lead Acid batteries need periodic maintenance, such as checking and topping electrolyte levels and cleaning terminals. If not maintained properly, corrosion builds up on terminals and decreases battery life.

AGM batteries have almost no maintenance needs, even though it is recommended to check electrolyte levels. They give better performance in deep discharge applications than Lead Acid type. However, AGM batteries still should not be deeply discharged.

AGM batteries are the preferred choice for most applications. They offer better performance than Lead Acid batteries, with no maintenance required. The main differences between them are performance and convenience. Lead Acid cells need regular maintenance, but are cheaper. While AGM cells offer superior performance and no maintenance, but are more expensive.


Lead Acid and AGM batteries have both been used for many purposes. Lead acid batteries are cheaper, but AGM batteries give better performance.

It’s important to pick the right one for the application. AGM batteries are good when you need quick performance, less maintenance, and a small size. Lead acid batteries may be best if you need low current use and are on a budget. Do research on the requirements for the application before you choose.

Frequently Asked Questions

Q1: What is the difference between Lead Acid and AGM batteries?

A1: Lead Acid batteries are more cost effective than AGM batteries, however AGM batteries are more efficient and require less maintenance. Lead Acid batteries have a liquid electrolyte and AGM batteries have an absorbent fiberglass material which acts as the electrolyte.

Q2: What are the advantages of AGM batteries?

A2: AGM batteries are more efficient than Lead Acid batteries, as they can be discharged deeper and recharged faster. They also require less maintenance, as they are sealed and spill-proof. Additionally, they are more vibration resistant and have a longer life-span.

Q3: What are the disadvantages of Lead Acid batteries?

A3: Lead Acid batteries are more susceptible to vibration damage and require more frequent maintenance than AGM batteries. They also have a shorter life-span and are less efficient, as they cannot be discharged as deeply or recharged as quickly.


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