Lead-Acid battery facts
Batteries are the heart of DC electrical systems. To understand why Pulse Technology helps overall vehicle performance, it is important to understand the functions of a battery:
Functions of a battery
- Supply power to starter and ignition systems to crank and start the engines.
- Supply extra power when vehicle's loads exceeds supply from the charge systems.
- Act as voltage stabilizers in DC electrical systems, reducing temporary voltage spikes.
- Act as energy storage devices to power DC applications where AC power is not available.
Sulphation occurs and increases every time batteries are used. It is part of the chemical reaction, which takes place in Lead-Acid batteries. When a battery is sulphated, its voltage is depressed. The battery no longer meets the demands of the electrical system. Electrical components are then subject to over-voltages, resulting in premature failure of components.
A lead acid battery is an electrochemical storage device. This chemical energy is converted to electrical energy when the battery is connected to an external load. The chemical energy is created by the chemical action between the materials which form the positive and negative plates of the battery, and the electrolyte:
The Positive Plate is made of Lead Dioxide (PbO2)
The Negative Plate is made of Sponge Lead (Pb)
The Electrolyte is made of Sulphuric Acid (H2SO4)
A battery relies upon clean plates and strong electrolyte to receive full charging current and offer full discharge current, a sulphated battery can do nither.
The Battery specific gravity (the unit of measurement of the sulphuric acid content of the electrolyte) of a fully charged 12-volt battery is 1.295 at 26 deg Celsius, this means that the sulphuric acid of a fully charged battery is 1.295 times heavier than pure water. As a battery becomes discharged, the strength of the specific gravity decreases because sulphur is leaving the electrolyte as it forms lead sulphate which adheres to the battery plates.
State of Charge / Specific Gravity Table (12V battery)
- Please note: values are approximate / indicative only as they vary marginally with temperature and battery type.
By the time the battery is discharged, the acid becomes dilute as the sulphur has adhered to the plates of the battery as lead sulphate crystals. When a discharged battery is recharged, the chemical processes within the battery should operate in reverse. The majority of the sulphate leaves the plates of the battery and returns to the electrolyte. However, a residue of sulphate remains on the plates of the battery. The quantity of this residue increases with each charge/discharge cycle of the battery. Over time, the battery plates become coated with an insulating layer of sulphate and the electrolyte is weakened because of the loss of Lead sulphur molecules from the solution. Both these factors inhibit the electron transfers and thus the energy producing function of the battery.