Leoch Battery UK

What causes batteries to fail prematurely?


If you’re a regular user of high performance leisure batteries, you’ll know that there’s nothing more frustrating than seeing the battery fail prematurely or even quicker than expected.

The technology incorporated into today’s batteries is such that they should provide a long-term solution to your energy requirements, if looked after carefully and monitored regularly. However, problems can arise if you fail to maintain the battery effectively…

Avoiding acid stratification

The Depth of Discharge for a standard leisure battery should be 50-60% at most (rising to around 80% for Gel Tubular batteries). However, you need to give the battery a reasonable level of charge to excite the acid or this can lead to acid stratification.

Acid stratification is a common cause of battery failure. In a stratified battery, the strength of the electrolyte becomes more concentrated at the bottom of the cell. This can be prevented by a reasonably high level of charge – approximately 15% of the Ah.

However, with a high level of charge heat created also expands the plates. Over time expansion and contraction of the plates causes the paste to fall away from the plates. One of the benefits of AGM and Gel Tubular batteries is that the Glass Fibre matting, or the GEL helps to hold the paste on the plate by keeping it compressed.

Partial State of Discharge leads to sulphation

Another major factor for early battery degradation is sulphation – brought about by a Partial State of Discharge.

This is when the lead acid battery is discharged, but not fully recharged. During discharge, small crystals of lead sulphate are created on the battery plates and are dissolved again during recharge. Leaving the battery partially charged, creates Sulphation, which is difficult to dissolve. This is known as PSOC failure (Partial State of Charge)

Consequently, it is important for lead acid batteries to be maintained fully charged.  If you only bring the battery back to 90% charge, sulphation starts to build and with each subsequent charge, you will see a slow deterioration.

The Latest Lead Carbon Batteries help prevent the above issues. Carbon added to the negative plate reduces sulphation, and the latest AGM Double separation helps prevent Acid Stratification.