Know Your Car Battery

With the various types of batteries to choose from, it is good to have a basic idea of their design and composition. Given below is a summarised description of the commonly used batteries:

Know Your Car Battery

Know Your Car Battery


There are different types of batteries used in the car industry. Essentially, an automotive battery starts the vehicle, powers its lamps and supplies current to devices such as audio system, AC and power windows. As you drive, the engine continually recharges the battery. It is also important to remember that these batteries have a certain life and at some of time you may need to replace the battery of a used car.

With the various types of batteries to choose from, it is good to have a basic idea of their design and composition. Given below is a summarised description of the commonly used batteries:



Wet/Flooded Battery: This is the oldest one of the most popular varieties of batteries. What makes it popular is its low price. It is also easy to maintain. The design uses some plates that are freely suspended. These plates are also insulated from each other with the negative plate being completely sealed in a separator bag. The fluid in the battery lasts until the battery dies and there is no need to keep topping it up.

The downside of wet battery is that it cannot take much load by powering too many systems. Also it can cause trouble in starting the car in winter or in cold regions.

This battery costs between Rs 2500 and 8000.


Calcium Alloy Battery: This battery gets a calcium alloy on its different charged plates. The calcium lessens the amount of fluid loss and the rate of self discharge is also very slow. Calcium alloy batteries are easy to maintain and do not need much care. They last for pretty long time.

It does have some disadvantages – the most crucial is that you can damage the battery seriously if you overcharge it. The bubbles that circulate through the fluid of battery are important and are responsible for mixing the various acid densities.

A calcium alloy battery can be bought for prices between Rs 3500 and 15000.


VRLA Battery: VRLA is an abbreviation for valve regulated lead acid battery. It is known to be a low maintenance and safe unit - the very name describes the safety valves on the battery box. All safety valves are pressurised. The mixture of fluid and gas helps in retaining the pressure and prevents any damage to the battery. Furthermore, it adds to the power output of the battery.


VRLA batteries are colloquially called sealed lead-acid batteries but they always have a safety pressure relief valve. As against flooded batteries they cannot spill their electrolyte if overturned. Because they use considerably less electrolyte than conventional lead-acid batteries, they are also known as acid starved batteries.

There are 2 broad sub categories of a VRLA battery:


1) Absorbent glass mat (AGM) battery – As the name suggests it uses glass mats that are very thin and keep the internal resistance in battery very low. The design makes a great battery to start the car because of a lot of power output comes from a very small volume.


2) GEL battery – It uses silicon to solidify the acid like a gel. This type of battery is tad inferior to the AGM but is much better than conventional wet/flooded battery.


VRLA units cost between Rs 8000 and 20000.


Lithium Ion Battery: This is a powerful and dynamic battery while also being light in weight. It is typically used in electric and hybrid cars because of its ability to store more energy. Lithium Ion battery or Li-ion battery gives considerable range to the vehicle making it fuel efficient. Some high performance or limited edition cars also use this battery type. An example is the Porsche 911 (2010 model) that has lithium ion battery to start the engine.

Lithium ion batteries are very expensive and this is why even the small electric vehicles (EVs) they power also become pricey in the market.

The price of this battery ranges between Rs 50,000 and 200000.


Taking care of your car battery

Cars are globally manufactured with compatibility to a certain kind of battery. You therefore need to choose yours as per the recommendation of the company that your car comes from. The charging relay and fuses are fitted according to the kind of battery used in a vehicle. The power output is also calculated accordingly. Changing the size of battery or using an incorrect battery type can cause serious problems with the electrical devices in the car. It also nullifies the manufacturer’s warranty.


As you care for other parts of your car, also keep a check on the battery. It should not show any signs of leakage and there should be no carbon deposits over it. If you notice any carbon specks or white / greenish spots on the battery wires, wipe them off with a cloth dipped in lukewarm water. After this, you can apply some grease on the surface to prevent such deposits in future.


Ensure that your battery wires are screwed in well because loose wires can get heated and in extreme cases may lead to a short circuit. Incorrectly attached wires will also affect the performance of battery adversely.


The entire unit of the battery should fit compactly in its case. A wobbly battery can get damaged easily. Once again, see that its wires are not exposed. Particularly, the positive (+) point of the wire must be covered - if it comes in contact with car body or any other wire in the engine bay, there may be a short circuit. Do not try to connect any other wire to the battery.


Taking your car for periodic services at authorised centres and driving in compliance with safety rules will help to improve the longevity of the vehicle and its parts. Happy Driving!