It is estimated that only 1 in 3 batteries sold today live to see their 5th birthday. The most common failure (80%) is from plate sulfation. This build up occurs when the battery is so deeply discharged that molecules in the electrolyte begin to coat the batteries lead plates. Before long the coating is so thick that the battery dies. There are several common causes of plate sulfation.

1. Fluid or electrolyte level too low- Battery plates exposed to air will immediately sulphate

2. Sitting too long between charges. As little as 24 hours in extreme hot weather or several days in cooler temperatures.

3. Some engines have a constant drain or parasitic load, e.g. a clock. As energy is depleted, sulphatingIt is estimated that only 1 in 3 batteries sold today live to see their 5th birthday. The most common failure (80%) is from plate sulfation. This build up occurs when the battery is so deeply discharged that molecules in the electrolyte begin to coat the batteries lead plates. Before long the coating is so thick that the battery dies. There are several common causes of plate sulfation.

1. Fluid or electrolyte level too low- Battery plates exposed to air will immediately sulfate

2. Sitting too long between charges. As little as 24 hours in extreme hot weather or several days in cooler temperatures.

3. Some engines have a constant drain or parasitic load, eg a clock. As energy is depleted, sulfation occurs.

4. Undercharging of the battery. Charging a battery to 85% of capacity will allow a chemical reaction where the 15% of electrolyte not full reactivated will allow sulfation to occur.

5. High temperatures of 38c plus (such as locking your mower in a closed shed during summer) increases the internal battery discharge. A new fully charged battery left standing at 38c for 30 days would most likely not start an engine.

6. Cold weather. A deeply discharged battery can freeze solid in sub zero temperatures.

If you have a volt meter here's a handy reference chart which will give you a good idea about the state of your battery. Simply read off the output voltage of your battery when not under load. occurs.

4. Undercharging of the battery. Charging a battery to 85% of capacity will allow a chemical reaction where the 15% of electrolyte not full reactivated will allow sulfation to occur.

5. High temperatures of 38c plus (such as locking your mower in a closed shed during summer) increases the internal battery discharge. A new fully charged battery left standing at 38c for 30 days would most likely not start an engine.

6. Cold weather. A deeply discharged battery can freeze solid in sub zero temperatures.

If you have a volt meter here's a handy reference chart which will give you a good idea about the state of your battery. Simply read off the output voltage of your battery when not under load.