Over time the sulphate deposits on the plates become hard and crystalline. When in this condition, plates will not accept a charge under normal conditions, and the accumulation of lead sulphate may cause short circuits during recharging or other mechanical damage to the battery. Often, hairline cracks appear in the plates causing open circuit conditions.

When a lead acid battery discharges or remains inactive, lead Sulphate forms on the battery plates. Over a short period of time, sulphate gradually accumulates and crystallises clogging the plates to the point where the battery will not accept or hold a charge. This process, known as sulphation happens to all lead acid batteries in all application. It is the leading cause of battery failure. Megapulse technology reverses sulphate accumulation in all lead batteries and it prevents sulphation from ever developing in new batteries. By pulsing a carefully controlled DC current into the battery, it re-energises crystallised sulphates deposited on the plates and returns them to the electrolyte as active sulphur molecules. With the plates kept clean, batteries will provide more power, faster recharge and longer battery life.

Batteries commonly fail because of sulphation. Sulphation occurs when a battery is discharged. The deeper the discharge, the more serious the sulphation. A battery relies on clean plates and strong electrolyte to both receive charging current and offer discharge current. A Sulphated battery can do neither. Sulphation also occurs when batteries are in an undercharged state. Battery theory states that cell voltage should read 2.45 volts per cell (i.e. 14.7 volts in the case of a 12 volt battery) from time to time to allow the negative plate to "form". If this does not occur, the negative plate remains mushy and subject to erosion from motion, vibration, etc. In automotive systems, alternators seldom exceed 14.2 volts. Battery theory states that 12-volt batteries must receive a minimum of 14.1 volts to maintain a charged state.