Gel Vs. Lead Batteries

Both flooded lead-acid batteries and gel cells have marine applications.

Gel-cell and flooded-cell lead-acid batteries are both based on the same lead-acid technology that dates back to the late 1800s. Gel cells are fully sealed and spillproof. Flooded batteries are more commonly used and less expensive than gel cells.

Flooded Battery

A standard lead-acid battery, called a flooded battery, immerses chemically treated lead plates in a sulfuric acid electrolyte. The reaction between the lead and the electrolyte solution produces a strong electric current. Flooded batteries vent gases into the air while charging.

Gell Cell

Gel cells also use lead and sufuric acid, but the acid is combined with a silica material in a semisolid state. Since these batteries are sealed, you must carefully match the battery with the charging system. Gases given off during overcharging may build up and explode the battery.

Position

Lead-acid batteries must be kept upright. The liquid acid sloshes in the battery and may leak if you tip it. Gel cells can operate in any position, though they may work at lower efficiency when tipped.

Self-Discharge

Virtually all batteries slowly lose charge with time, even sitting on the shelf. Flooded batteries self-discharge about 1 percent per day. Gel batteries discharge at a rate of 1 percent to 3 percent per month.

Safety

Gel batteries are sealed and won't leak if the case is cracked. The silica immobilizes the acid. Flooded batteries may leak sulfuric acid, a corrosive liquid, if tipped or punctured.

References

• BD Batteries: Battery Type Comparison

Resources

• Von Wetzel: Flooded vs AGM and Gel Batteries