How do car batteries work?

Car batteries convert chemical energy into electricity. Most car batteries rely on a lead-acid chemical reaction. These batteries falls into the “SLI” category, “Starting, Lihting, Ignition”. This type of battery provides short bursts of energy to power your lights, accessories and engine. The battery jolts the engine to life and the alternator supplies the rest of the power. 

A typical car battery has six cells, each cells can make 3 volts of energy, that makes it a 12V battery. Each cell has a lead and lead dioxide plate. The plates are submerged in sulphuric acid, this triggers a reaction between the two plates. The sulphuric acid acts as a catalyst. The acid triggers a reaction on the lead dioxide plate, causing the plate to produce lead sulphate and ions. The ions produced by the lead dioxide plate react with the adjacent lead plate to produce to produce hydrogen and lead sulphate. The chemical reaction produces electrons that race around the plates and generate electricity. This electricity flows out of the battery terminals to start your engine, turn on your lights and play the radio. This chemical reaction is entirely reversible, this allows you to charge your battery. 

Car battery care and life expectancy

The average life expectancy of your car battery is expected to be between four to six years, but can be up to ten years. There are several factors that can affect the lifespan of your car battery, such as weather conditions, vehicle type and driving habits. 

Why is your car battery flat?

– Check all of the electrical connection and make sure the battery is kept clean and dry.   If corrosion has built up on your terminals over time, you can use a solution of baking   sofa and water with a toothbrush to clean the corroded terminal. Make sure you      disconnect the negative terminal first. And when reapplying the terminals, connect the       positive terminal first.

– Frequent short car trips contribute to a shorter lifespan for car batteries. It takes    approximately 8 hours of continuous driving for the alternator to fully charge the battery.   If the the battery doesn’t often receive a full charge, crystalline deposits can form on the   negative plates and consequently prevents the battery from charging properly, this is   called sulphation. If daily short drives make up the majority of your driving, avoid using  auxliary controls unecessarilly. This will prolong the lifespan of the battery and save on  fuel.

– Cold weather makes it more difficult for an already weakened battery to hold it’s   charge. Storing your car in a garage during when the weather gets colder will keep the   battery warmer and easier to charge.

– If your car isn’t in use for long periods of time, you can disconnect the negative    terminal. This will help extend the life of your battery.

-The electrolyte (water/acid) solution levels may be low. If your battery is not          maintenance-free, you may need to change the solution levels. If the levels are low,    make sure to use the necessary safety precautions when you are handling battery acid.   Only use distilled water, or you risk damaging your battery.

Charging your battery

– The type of charger you own is important when it comes to the safety of charging your   vehicle. Make sure you choose a charger specific to the needs of you car from an MTA     member

– It is safer and better for your battery to choos a slow charging method. A fast charge    increases the potential of overcharging your battery and can permanently damage it.

Replacement and recycling 

– It is illegal to dispose of your car battery with normal household waste, as the battery     parts can be very toxic. Your local car garage, car wrecker or recycling centre will take     care of it for a small fee

– If the battery is still in reasonable condition, it can be reconditioned for use or the    components will be extracted and melted for recycling. 

We can recycle or recondition your second hand batteries, we can also supply you with a great quality second-hand battery. Contact us today to see how we can help you.

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