The auto market is filled with a vast array of batteries which makes choosing the best car battery for your car and for your use-case a confusing business. There are no strict rules that can say that one battery is better that the other. It all depends on what you need. Obviously, when it comes to things like durability and longevity, some batteries are better than the other. But when it comes to the cost, maintenance, casing and other parameter, it all comes down to what you need.
How a Car Battery Works?
Car batteries are typical lead-acid batteries that are not so different from general household power supply batteries. Car batteries are generally used for three things – start, lighting and ignition. These are called SLI in short. Once the ignition happens and the car starts running, the power to the car is supplied via the alternator.
Most modern car batteries have six cells that are serially connected. They output a total of 12 volts. The best car battery will maintain this constant voltage for a long time as it discharges. A voltage regulator is attached to them so even out voltage sparks. Most other automotive accessories, like phone chargers run with 12 volts input.
Lead-acid batteries are typically very heavy and provides low energy output even though they have a large volume. These batteries are one of the most ancient types, but they are still in use because they can provide a large amount of surge current. These high currents are very much essential in automobiles. Moreover, they are cheaper than any other battery technology.
Lead acid batteries also need maintenance. When charged, the anode is lead, the cathode is lead oxide and aqueous sulphuric acid is used as an electrode. When discharged completely, both the anode and the cathodes become lead sulphate. Once in the while, the electrolyte is needed to be replaced or distilled water is to be added. Nowadays, most car batteries are maintenance free.
Car Battery Specifications
If you are trying to find out the best car battery for your car, you need to be aware of a few specifications that are particular to car batteries only.
- Physical Size: Each automobile has their battery group size. It is similar to how AA or AAA batteries are used in home electronics. Similarly, cars too have battery group sizes. Even though all batteries provide the same voltage and current, the different size determines a different value of the totally energy output that it can give. More importantly, not all batteries will fit in all cars.
- Ampere Hours: This is the energy storage capacity. The higher the value, the slower it will take to completely discharge. The best car battery will have a very high Ah rating, but the price is also exponentially high.
- Cranking Amperes: An important specification is you live in cold areas. CA determines the current that the battery can provide at 0 °C. CCA or Cold Cranking Amperes is the current it can provide a -180 °C. Most cars with computer controlled fuel injection systems only takes a few seconds to start though. Similarly, there is also an HCA or Hot Cranking Amperes.
- Reserve Capacity Minutes: RCM is the batteries ability to sustain a minimum electrical load. It’s generally expressed in minutes and says how many minutes the battery can give 25 amperes before the voltage drops to 10.5V.
- Terminal Location: Usually batteries with terminals at the top provide easier cleaning and maintenance.