What is a maintenance-free battery?
A maintenance-free battery is a battery that typically comes sealed for life from the manufacturer and does not require any maintenance of the electrolyte levels.
- Maintenance-free batteries are also called Valve Regulated Lead Acid Batteries.
- There are two main types of maintenance-free battery: Gel Medium and Absorbent Glass Mat.
- Maintenance-free batteries tend to have a longer lifespan than maintainable batteries.
Understanding maintenance-free batteries
Maintenance-free batteries are batteries that arrive from the manufacturer in a sealed state and do not require any maintenance of the electrolyte levels. They are also called Valve Regulated Lead Acid Batteries, or VRLA batteries.
There are two main types of maintenance-free batteries: Gel medium, where the acid is in a gel form; and Absorbent Glass Mat where the electrolyte uses glass fibre mats.
Maintainable and maintenance-free batteries both function in similar ways: they both are filled with an electrolyte through which an electric current flows from terminal to terminal. The main difference is that maintainable batteries come with removable caps that allow you to check the electrolyte levels manually, while maintenance-free batteries come sealed from the manufacturer.
Maintainable batteries often lose their electrolyte solution due to overcharging, heat exposure, or simply due to evaporation. The electrolyte levels will need to be topped up using distilled water in order to extend their lifespan.
Maintenance-free batteries, on the other hand, do not require any maintenance of electrolyte levels and therefore tend to have a much longer lifespan over their counterparts so long as they are stored properly and kept fully charged.
Battery – A storage device for electrical energy, typically in a chemical solution, that can be used as a source of power.
Battery Cycle Life – The typical number of charge and discharge cycles that a battery can undergo before it reaches the end of its useful life.
Battery Life – The length of time a device can continue to work before it needs its battery to be recharged.