What is a Lead-acid battery and the things you need to know

What is a Lead-acid battery and the things you need to know />


At BatteryPower Zone (BPZ) we pride ourselves as being a transparent company who educates our customers about our products so that they can make informed decisions when it comes to buying the best batteries.

The lead-acid battery is the most widely used car battery in today's market. If you look under your hood you will most likely have one in your car.

In this article, we will cover the lead-acid battery basic definition, its working principle, and its benefits.

What is a lead-acid battery?

In simple terms, a lead-acid battery makes use of a reaction between lead oxide, sponge lead and acid (normally sulphuric acid) to convert chemical energy into electrical energy. The working principle of the lead-acid battery relies on a chemical reaction known as electrolysis. The reaction occurs differently during charging and discharging.

During charging, when a voltage is applied to the two lead electrodes i.e. The anode (positive) and the cathode (negative). The charge splits the sulphuric acid into hydrogen and sulfate ions. The subsequent reaction leads to the anode staying as it is in the form of sponge lead while the cathode reacts with the oxygen to form lead oxide.

During discharging i.e. when the load is connected to the battery, another similar reaction occurs which results in the formation of lead sulphate and water. The reaction itself creates a flow of electrons or current through the load.  During discharge the sulphate is absorbed into the positive and negative plates forming what is commonly known as sulphation, resulting in the liquid becoming H20 (water).  The charge current dispels the sulphate off the plates back into the water reforming the electrolyte (sulphuric acid).  It is imperative that the charge process happens as soon as possible after discharging the battery.  Failure to do this and if the battery is left in a discharged state the sulphation process may become permanent and may cause the battery to fail prematurely.

What are lead-acid batteries used for?

Lead-acid batteries are used extensively in cars and trucks where they serve the Starting, Lighting, and Ignition (SLI-batteries) functions in the vehicle.

Generally, they are affordable and reliable options for this purpose. Different variants of lead-acid batteries can be used for UPS, Renewable Energy, Stationary Applications, Motive applications such as Golf Carts and Wheelchairs, Marine and Leisure etc.  It must be noted that batteries used in these applications vary considerably in their design when compared to SLI batteries. It is not advisable to use SLI batteries in auxiliary power applications.

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