What is the Difference in a Flooded Lead-Acid Battery and a Sealed Lead-Acid Battery?
Understanding battery types and chemistries can be confusing for those new to solar energy. It’s important to understand the basics of how they are different so you can choose the right battery type for your solar power application. Today we will address the difference in a flooded lead-acid battery and a sealed lead-acid battery.
A flooded battery with lead-acid chemistry is the most common in the industry compared to a sealed lead-acid battery, which are sometimes referred to as a valve regulated battery, an AGM battery (Absorbed Glass Mat) or a gel battery. On paper, there are many similarities between the two battery types. Most of that has to do with their performance, their depth of discharge abilities, their warranty and their cycle life.
The largest difference between the two battery types is the issue of battery maintenance. With a flooded lead acid battery, water needs to be added every so often, periodic equalization needs to be performed and the specific gravity of the electrolyte needs to be measured on occasion with a hydrometer. Another distinguishing factor with a flooded battery is that they can off-gas hydrogen in certain battery charging conditions, resulting in the battery needing to be vented to release the fumes. In stark contrast to the flooded battery, a sealed lead-acid battery requires no maintenance and do not require venting which is a large selling point for those that do not want to deal with battery maintenance. One potential drawback of a sealed lead-acid battery is that due to the inability to maintain the battery, it may not perform at optimum levels as its flooded counterpart.
Aside from the maintenance aspect, the two types of batteries are similar in size, weight, performance and efficiency. There are some minor pros and cons between the two, but the maintenance factor is the largest and most noticeable difference when customers decide on which battery type to purchase.