AGM Battery vs. Lead Acid: A Beginner’s Guide 2024

Renogy

Oct 5th 2024

There are tons of battery categories in the market, each promising better performance, safety, and durability. Among the numerous battery choices in the market, are the AGM and lead acid batteries. Both battery types are quite popular in various applications.

Although AMG and lead acid batteries have a few similarities, they differ in performance, construction, safety, and sustainability. So, which is a better choice between AGM battery vs. lead acid battery?

This helpful article will guide you through understanding each battery type, and their differences, advantages, and disadvantages. Keep reading!

What is an AGM Battery?

What is AGM battery

Absorbent Glass Mat (AGM) batteries are similar to lead-acid batteries, in that they also have six cells each with an insulating separator.

However, they feature a fiberglass mat material that absorbs electrolytes, as a substitute for the electrolyte liquid used in standard batteries.

Additionally, in AGM batteries, the cells are compressed to keep the acid solution pressed between plates.

Advantages of AGM Batteries

Improved Safety- Due to the immobile electrolyte, there are no acid leaks or spillages, making AGM safer than lead-acid batteries.
Longer Lifespan- Due to the immobile electrolyte, AGM batteries do not experience internal corrosion or damage. As a result, AGMs serve you longer thus saving you a decent amount of money in the long run.
Outstanding Performance- AGM batteries have high power output and provide more energy than the lead-acid batteries. With the great power output, AGM batteries are excellent for applications demanding high and sustained power such as solar systems or larger vehicles.
Fast Charging- AGM batteries charge faster than lead acid batteries, thanks to their enhanced internal conductivity. They are ideal in applications where fast charging capabilities are essential, like in high-demand situations or in emergency power systems.
Enhanced Durability- Due to immobilized electrolytes and an extremely strong construction, AGM batteries are highly resistant to shocks and vibrations.

Disadvantages

High Costs- Due to high-quality construction and enhanced safety features, AGM batteries come at a higher price, compared to lead-acid batteries.
Sensitive to Temperatures- AGM batteries do not perform well under extreme temperatures. Their performance reduces if exposed to extremely cold or hot conditions. Additionally, it could lead to damage.

What is Lead Acid Battery?

What is Lead Acid battery

Lead-acid batteries are the most prevalent and are readily available in various parts of the world. Lead acid batteries are used in several types of applications such as motor vehicles, backup power systems, solar systems, among others. They are highly affordable and they feature a simple structure, thus making them more common with consumers.

Lead acid batteries utilize the reaction between lead acid and sulfuric acid. To trigger a chemical reaction, lead is saturated in sulfuric acid. Through the reaction process, the battery generates electricity. During the recharging of the battery, this reaction process is reversed.

Advantages Lead-Acid Batteries

Affordability- Lead acid batteries are fairly priced compared to AGM batteries. Their low-priced nature makes them suitable for low-budget applications.
High Capacity- Lead-acid batteries have a relatively higher capacity. They are capable of storing more energy, which is suitable for applications such as long-distance travel, off-grid systems, or in applications requiring relatively longer run time.
Easily Accessible- The most common battery type globally is lead-acid. Their ease of availability makes them an attractive choice in remote areas and during emergencies.

Disadvantages of Lead-Acid Batteries

Lower Output- Lead-acid batteries have a lower output compared to AGM batteries. In applications requiring long run times, lead-acid may not be a sustainable choice.
Safety Concerns- The liquid electrolyte in lead-acid batteries may accidentally spill or leak, thus posing health and safety issues.
Reduced Durability- Lead-acid batteries have a shorter life expectancy than AGM batteries. They easily get damaged due to vibrations, extreme temperatures, and shock.
Slow Charging Rate- Lead-acid batteries have a slower charging rate than AGM batteries. This is due to low internal conductivity. When it comes to emergency power systems, they are not dependable.
Regular Maintenance- Lead-acid batteries need maintenance more often than AGM counterparts. You must clean the terminals and top-up the electrolyte liquid often which is time-consuming.

Key Differences: AGM Battery Vs. Lead Acid Battery

Here are some major differences between AGM batteries and lead acid batteries.

1. The Working Principle

AGM batteries have a special element between the plates which reacts with the electrolyte solution. When the material saturates the electrolyte, a current is formed.

Therefore, it is capable of storing power in suspension mode, unlike the liquid electrolyte batteries. When the battery is activated, ionized electrolytes are transferred from the AGM material to the plates.

Lead acid batteries feature a simplistic construction. The liquid electrolyte facilitates a chemical reaction in the battery which supplies power to the circuit.

2. Durability and Resistance

AGM batteries have a tougher construction than lead acid batteries. They are resistant to vibrations and shock. Due to their internal and electrolyte composition, they are resistant to damages.

Lead acid batteries are more suitable for stationary applications because they are predisposed to damage. They are less resilient to vibrations and shock. The electrolyte leaks easily which can be hazardous.

3. Charging Duration

AGM batteries charge faster than lead acid batteries due to their low internal resistance. Lead acid batteries are almost 5 times slower than AGM during charging.

4. Discharge

Typically, AGM batteries have a depth of discharge of 80% higher than lead acid batteries. AGM batteries are a better choice for deep-cycle applications.

Lead acid batteries have a 50% depth of discharge. If the battery falls below 50% of its capacity, it loses its effectiveness and its performance is affected. Therefore, lead acid batteries demand charging more frequently than AGM batteries.

5. Extreme Temperature Tolerance

AGM batteries have a high tolerance against extreme temperatures. Due to the nature of their electrolyte, AGM batteries are not badly affected by harsh environmental temperatures.

In cold weather, the electrolyte liquid in lead-acid batteries can freeze on the plates. Freezing of the electrolyte can cause damage to the plates and cracking on the casing resulting in leakages. During hotter temperatures, the electrolytes on lead-acid batteries can evaporate.

The following comparison table demonstrates the difference between AGM battery Vs lead acid.

Feature	AGM Batteries	Lead Acid Batteries
Electrolyte	Immobilized Absorbent Glass Mat	Liquid solution
Spill or leak-proof	Yes	No
Durability	Better resistance to vibration and shocks	Less durable and more susceptible to damage
Performance	Long life span, faster charging rate, and high power output.	Slower charging rate, shorter life span, and lower power output.
Cost	Expensive	Affordable
Temperature Sensitivity	Sensitive to extreme temperature	Highly Sensitive to extreme temperature
Capacity	Low capacity	Higher capacity
Maintenance	Low maintenance needs	High maintenance requirements
Lifespan	4 to 7 years	3 to 5 years
Weight	20-30 kg (44-66 lbs)	25-40 kg (55-88 lbs)
Dimensions	Larger (13 x 7 x 8 inches)	Larger (10 x 6 x 8 inches)
Operating Temperatures	-20°C to 50°C (-4°F to 122°F)	-10°C to 50°C (14 °F to 122°F)
Safety	Zero leakages or spills	Risk of leakage and emitting gasses
Price Range	$150-300 per battery	$50-150 per battery
Application	Automotive, marine, backup power, etc.	Automotive, marine, backup power, golf carts etc.
Environmental Friendliness	Recyclable, less harmful	Recyclable, harmful materials
Cycle Life	1200 charging cycles	300 charging cycles

The Differences in Power Output of AGM Vs. Lead Acid Batteries

AGM batteries have a higher power output than lead acid. They are capable of delivering more energy, which translates to robust performance in applications demanding higher power, such as solar systems or high-performance vehicles.

AGM batteries require between 14.6v and 14.8v when performing a full charge from the state of discharge. On the other hand, lead acid batteries require between 13.8v to 14.4v.

Additionally, AGM batteries have a lower internal resistance, which allows them to discharge power proficiently. Conversely, lead acid batteries have lower power density due to their higher internal resistance. They are incapable of delivering large current bursts as compared to AGM batteries.

AGM batteries maintain a stable voltage throughout their discharge cycle. They tend to have a consistent power output even during high-drain situations. On the other hand, regular lead acid battery voltage is usually unstable during discharge and high-load conditions, resulting in inconsistent power delivery.

Are AGM Batteries Safer Than Lead Acid?

Yes. AGM batteries are safer compared to lead-acid batteries. During charging and discharging processes, lead acid batteries discharge hydrogen and oxygen gasses which is dangerous when inhaled.

You need good ventilation when using lead-acid batteries to prevent the risk of inhaling these toxic gasses. The liquid electrolyte in lead-acid batteries may leak or spill if not well maintained or handled.

AGM batteries are well-known for their improved safety. They have recombination capabilities, meaning the gasses emitted are recombined during charging. The recombination process eliminates any gas emission. As such AGM batteries are safe to use in enclosed spaces. Additionally, AGM has immobilized electrolytes, thus no risks of spillage or leakages and corrosions.

Which is More Expensive, AGM or Lead Car Batteries?

Which one is more expensive, AGM battery vs lead acid? Ordinarily, AGM batteries are more expensive than lead-acid batteries. The cost difference is quite significant, ranging between 40 to 100% of the cost of lead-acid batteries.

Although AGM batteries are pricier, they last longer hence saving you money in the long term. Additionally, AGMs are more efficient than lead acid. Note, the cost of the batteries vary depending on the brand.

Environmental Adaptability: Which Battery Performs Better?

AGM batteries are designed to perform better in harsh environmental conditions than lead acid batteries.

In colder temperatures, AGM batteries are resistant to freezing because they are completely sealed and have immobilized electrolytes. Lead acid batteries freeze when exposed to chilly environments due to the presence of liquid electrolytes. The freezing may lead to battery cracking causing permanent damage.

In hot climatic conditions, AGM batteries are equally less sensitive to high temperatures, which minimizes the risk of damage. When exposed to hot environmental conditions, lead acid batteries are susceptible to damage and reduced performance.

AGM batteries have been proven to be resistant to vibrations, making them favorable for applications such as marine or off-roading conditions. Lead acid batteries are susceptible to damaged plates due to vibrations and swishing of the liquid electrolyte.

Choose the Right AGM Battery: Renogy AGM Battery

There is no doubt that AGM batteries are superior to lead acid batteries. They are suitable for a wide range of applications where safety, durability, and high performance are critical requirements.

When looking for an AGM battery, one of the main factors to consider is your budget. Here is an AGM battery we recommend:

Renogy Deep Cycle AGM Battery 12 Volt 100Ah

Renogy is a leading brand trusted by customers globally. In the past six years, it has sold over 230,000 units of 12V Deep Cycle AGM Battery.

Renogy's AGM battery is designed for exceptional performance across extreme temperatures, from -4 to 140°F. Its sealed design minimizes troubleshooting, making it ideal for solar systems and diverse applications. With an electrolyte formulated for high chemical stability, it ensures enhanced safety, even in confined spaces.

To prolong battery life, it's recommended to use the Renogy 500A Monitor and maintain a depth of discharge below 50%. Reliable and highly efficient, this battery is suitable for vehicles, household emergencies, and solar energy solutions.

Conclusion

After reading through our guide, which battery type would you choose for your applications? Looking to upgrade your regular lead acid battery, consider the Renogy Absorbed Glass Mat batteries.

AGM batteries boast superior technology and improved safety than lead acid batteries. Although expensive, they are more durable, thus saving you significant money in the long run.

Frequently Asked Questions About AGM Battery vs. Lead Acid

1. How long do the AGM and Lead Acid batteries last?

Generally, the lifespan of any battery is dependent majorly on usage, environmental factors, and maintenance. AGM batteries have a lengthier lifespan than lead-acid batteries. The average lifespan of AGMs is four to seven years, while lead acid is three to five years.

2. Can I swap a lead acid with an AGM battery for my vehicle?

In most cases, AGM batteries are compatible with lead-acid batteries. However, remember not all cars are compatible with AGM batteries. Before swapping the batteries, consult with a professional technician.

3. Are AGMs a better choice if I live in colder climates?

AGM batteries have a high cold-cranking amp rating. It means they can survive through extremely colder temperatures better than lead acid batteries. The immobilized electrolyte in AGMs is slow to freezing, compared to the liquid electrolyte in lead acid.

4. Are both Lead-acid and AGM batteries recyclable?

All lead acid batteries, including the AGMs, can be recycled. All components of these batteries can be reprocessed into usable parts. So, it is safe to say these batteries are eco-friendly.