In addition to the traditional, ‘wet’ batteries and in response to market demand for batteries that no longer require to be topped up, maintenance-free batteries have been introduced. We call these fully maintenance-free batteries. They are also called VRLA, or “Valve Regulated Lead Acid” batteries.

Maintenance-free batteries should never be topped up, therefore there are no filler caps on top. The filler cap is replaced by an over-pressure valve that is normally closed. Any gas that forms ends up being recombined in the cell as water. This way there is always sufficient electrolyte in the battery. Good quality maintenance-free batteries have the advantage of being guaranteed for life! Naturally the user never forgets to carry out maintenance. Maintenance-free batteries have to be charged up with a charger that is suitable for this type of battery.

The maintenance-free group of batteries includes types where the acid is in a gel form (Gel) as well as batteries that use glass fibre mats (AGM = Absorbent Glass Mat).

What is the difference between GEL and AGM?

AGM batteries use separators consisting of a sponge-like glass fibre mat that is squeezed between the flat battery plates. The electrolyte is incorporated in the glass fibre mat. The first AGM batteries were developed during the 1980’s in Japan and were used mainly in the UPS market. In the meantime development has continued and there are now AGM batteries for the cyclical battery market.

GEL batteries use traditional separators, except that a silicate is added to the acid whereby the acid becomes a gel after initial filling. Gel batteries have been in existence since the 1950’s and have in the meantime created a good reputation for maintenance-free batteries.

For advice about the various technologies available, simply contact Emrol. You don’t have to be a battery expert yourself, because we’ll carefully guide you through the selection process and at the end present you with various price options based on ‘good – better – best’. Contact us today with your battery queries. If necessary we will visit you on-site. Ex stock batteries delivered within 24 hours. We can meet your demands immediately 95% of the time.

The real difference between maintenance-free semi-traction, deep-cycle, traction and 2 volt cells lies in the number of charging cycles possible. The intensity of usage of the machine (day/night, daily, weekly, etc.) largely determines the type of traction battery you should choose.

The following diagram can be used as an aid for making the choice between the various types of maintenance-free batteries. It rates the different types according to the application, life-span, budget and guarantee. The overview acts simply as a guide in your search for the correct maintenance-free battery. The product description pages go deeper into the properties of the maintenance-free semi-traction, deep-cycle, traction and 2 volt cells.

Semi-traction Deep-Cycle Traction 2V Cells
Usage 1 x week 2-4 x week 4-7 x week 1-7 x week
# Cycles 300 400-500 600-800 1000
Warranty 2 years 1 year 1,5 year 1 + 3 years