AGM vs. Flooded Batteries

Chances are that you are using rechargeable batteries in some capacity within your home or car. According to some sources, almost half of all battery sales are categorized as renewable batteries, such as AGM batteries or flooded batteries. If you are trying to understand the difference between these two types of batteries, here is everything you need to know about AGM vs. flooded batteries for your home:  

AGM vs. Flooded Batteries: The Basics


Before we dive into the difference between AGM and flooded batteries, it is important to note their similarities. Both types of batteries are considered lead batteries because they contain an electrolyte solution. This solution presents in different forms (dry in AGM batteries and liquid in flooded batteries). 


The electrolyte solution causes a chemical reaction with the production of electrons. The battery charges itself when it comes into contact with a reverse current. However, this is where the similarity between the two types of batteries comes to an end. 


Let’s take a closer look at how each of these batteries functions to help you decide which one is the right pick for your home: 

AGM Batteries


Absorbed glass mat (AGM) batteries are a great option for those who want maintenance-free upkeep with their rechargeable batteries. They are designed with a glass mat separator which is where their name is derived. In this battery style, the separator serves as a wick for the electrolyte solution that must move between battery plates. The electrolyte solution is stored in a dry state as opposed to a liquid state. 


When you want to tap into the energy of your battery, that electrolyte solution is then moved from the separator to the battery plates and can deliver at optimal capacity. 


AGM batteries are great because they don’t require any maintenance, whereas flooded batteries do. Performance-wise, AGM batteries tend to do better than flooded batteries due to the fact that they have no liquid and only minimal gassing. They are also spill-proof, so you won’t deal with any electrolyte loss if the battery gets flipped over. 


On the other hand, there are some disadvantages to using AGM batteries. They tend to be a bit more sensitive to both over and undercharging. This sensitivity can impact how long the battery will last and perform at optimal levels. 


These batteries are commonly used in off-grid power systems with renewable energy systems such as solar power. 

Flooded Batteries


While AGM batteries have a lot of benefits for off-grid systems, it’s still more common to see flooded batteries on the market. They are sometimes referred to as wet cell batteries because they use a liquid electrolyte or acid. This liquid must be regularly maintained if you want your flooded batteries to perform at their highest level. 


You will need to have flooded batteries maintained by a professional on a regular basis to ensure that they have the proper acid levels. This is an added cost to maintain your home on this type of battery, but they do tend to last longer than AGM batteries when maintenance is performed. 


These batteries are most commonly used for backup power applications and energy storage from the grid. 


You must be extremely careful with flooded batteries in a way that you don’t have to be with AGM batteries. In addition to having routine maintenance done on flooded batteries, you also have to be cautious with them. Any type of harsh movement can impact its ability to function at the highest level. 


Be sure to store your flooded batteries in an area that is mostly protected from the elements. The extreme temperatures found in Winnipeg, particularly during the winter months, can spell major problems for your flooded batteries. The acid inside the battery can actually freeze in cold weather. Similarly, it can also evaporate in the brutal heat of the summer. 

Should You Use AGM Batteries or Flooded Batteries? 


Both of these prominent types of batteries are great for use with solar systems that are designed to take your home off-grid. If you don’t mind the maintenance and upkeep required with flooded batteries, then you might like the idea of the longevity of the battery. 


On the other hand, an AGM battery is more durable due to the dry electrolyte solution. It is less influenced by the weather conditions or movement from one location to another. However, you may have to replace it more frequently than you would with a flooded battery. 


If you are thinking about installing solar power in Winnipeg and aren’t sure what type of battery backup to use, Powertec Solar can help you figure out the best option based on your needs and the needs of your home. Allow us to conduct a solar feasibility analysis to guide you through the process of finding exactly what you need to make the switch to solar!