WHAT IS BATTERY?

A battery is an electro-chemical source of energy, which releases electrical energy at a controlled rate. The typical battery is made up of positive and negative plates immersed in an electrolyte, the whole assembly being within a container.

All Battery Factory Sombor batteries are lead-acid batteries, which mean that they have positive and negative electrodes made of lead compounds in a dilute sulphuric acid electrolyte. Lead-acid batteries belong to the group of secondary batteries, which means that they can be recharged after they have been discharged. Primary batteries can be discharged only once and then have to be thrown away; examples are some types of torch and radio batteries.

WHAT DOES THE BATTERY WORK?

The positive electrode is made of lead dioxide and the negative electrode is of porous lead. When a consumer is connected'to the battery (lamp or starter-motor) electric current will start flowing through the electrolyte, which will supply the consumer with electrical energy. This will trigger a chemical reaction within the battery causing formation of lead sulphate on both plate types, i.e. the battery will start discharging.

The battery may be recharged from an external source such as an alternator, dynamo or a charging unit. As soon as an external source is connected, the lead sulphate returns to starting material, i.e. into lead dioxide and porous lead.

During recharging, electricity causes decomposition (hydrolysis) of water within the electrolyte breaking it up to hydrogen and oxygen, which escape in the form of gas. That is why gas is released during battery recharge.

WHAT MATERIAL IS THE BATTERY MADE OF?

GRIDS - Grids made of lead alloy make the active material stronger since pure lead is too soft for the purpose. Apart from giving mechanical support to active material, grids conduct electricity whenever a consumer is connected to the battery.

ACTIVE MATERIAL - Active material is made of a mixture of lead oxide and lead sulphate, which turns into lead dioxide at the positive plate and porous lead at the negative plate during initial charging. The negative active material contains small quantities of additives, which facilitate better discharge performance at low temperatures. The grid with active material is called the plate.

ELECTROLYTE - The electrolyte is diluted sulphuric acid, which serves as a conductor to transport electrical ions between the positive and negative plates when the battery is discharged or recharged. The acid also takes part in the discharge as the sulphate ions react chemically at the electrodes to produce lead sulphate.

SEPARATOR - The separator is an insulator between the positive and negative plate preventing thus a shortcut. It has to be micro-porous to enable ions flowing from one to the other plate to pass through it. It also must be resistant to high temperatures as well as conditions of intensive acidicoxidation.The majority of modern separators are manufactured of micro-porous polyethylene of appropriate characteristics for use in batteries.

CONTAINER AND LID - These are normally made of polypropylene, which is a light but strong plastic. Unlike some plastics, it does not become brittle when it is cold and so can resist knocks during handling. It is not attacked by acid and it can also withstand the fluids (petrol, diesel, brake-fluid, antifreeze) normally found on a vehicle.

MAINTENANCE-FREE BATTERY?

Batteries manufactured 30 years ago were wasting water too quickly making it necessary for drivers to check water level in battery once a week. However, modern, maintenance free batteries do not need fill-up with water during their lifetime, under normal operating conditions. During the same period battery life has doubled.Earlier, 10% of antimony was added to lead alloy to improve the strength of lead in grids. However, it had a negative effect since a certain quantity of antimony dissolved in the acid, and resulted in the battery losing water.Due to improved technology, the 10% level of antimony could be reduced to 1.5% and batteries demanded maintenance once a yearonly. The present state of art in battery manufacture makes it possible that only 0.1% calcium is used in the lead alloy to create the same strength effect. Thus there is less contamination of the acid and much reduced water loss. These are maintenance free batteries,where no fill up is necessary during their lifetime.

SERVICE PROBLEMS

Overcharge

Modern car charging systems allow only a small current to flow into the battery when it is fully charged. If there is a fault in the alternator, however, a much higher current will pass through the battery all the time that the car is running. This current will cause the battery to lose water rapidly, destroying the maintenance free characteristics of the battery, and will also reduce the life of the battery by damaging the positive grids. Adark brown/black color on the bottoms of the vent-plugs is the strong sign of overcharging. If the alternator has a voltage above about 14.4 V at normal temperatures, this is a sign that the charging system is faulty.

Deep cycle

Modern charging systems of vehicles keep the battery in a high state-of-charge. However, under abnormal conditions such as when parking the vehicle with headlights turned on, the battery will discharge. Furthermore, modern vehicles contain other consumers as well such as on-board computer, alarm, clock etc., and this will cause the battery to become discharged. Vehicle batteries are designed to be recharged a certain number of times. However, they are not suitable for applications where deep cycle appears.

Such applications require batteries of other types that have a special construction to enable them to be deep cycled on a continuing basis. Continual deep cycling of vehicle batteries will cause failure as the positive active material will gradually fall to the bottom of the battery, reducing the ability of the plates to store electricity. A large number of small black/brown particles in the electrolyte are a strong indication that the battery has been deep cycled.

Sulphation

Sulphation is a process that occurs whenever a battery is discharged. During the process of recharging, lead sulphate is changed back into active material. If a battery is left flat for a period of time, sulphation slowly changes its form and cannot be changed back into active material on charging. Therefore, the battery will not return to give its original performance.

Undercharge

Undercharge occurs if the battery is not receiving enough charge to return to a full state-of-charge. This will slowly cause sulphation and occurs if the car is being used only occasionally for short journeys, or for stop-start urban motoring. Undercharging also occurs when the alternator voltage is in the region of 13.6-13.8 V.

COLD CRANKING PERFORMANCE (AMPER)

The Cold Cranking Performance (CCA) measures the starting performance of the battery. In simple terms, the higher the CCA, the easier it will be to start the vehicle. This test is starting test according to the EN 50342 standard. Other manufacturers use different standard tests such as DIN, JIS, and SAE etc.

The test specifies that the battery at a temperature of -18°C will deliver a current equal to the Cold Cranking Amps for 10 seconds with the voltage staying above 7.5 volts.

Battery performance drops off quickly with the temperature, so this test is a good check of a battery's starting ability..

AMPER-HOUR CAPACITY AT 20 HOUR RATE (Ah)

The Ampere-Hour capacity measures the total amount of electricity stored in a battery.

An Ampere-Hour represents the amount of electricity when a current of 1 Ampere passes for 1 hour.

The Ampere-Hour Capacity varies with the rate at which the battery is discharged; the slower the discharge, the greater the amount of electricity that the battery will deliver.

The Ampere-Hour Capacity is the amount of electricity that a battery will deliver during 20 hours of operation, before the voltage drops below 10.5 V. For example, a 60 Ah battery will deliver a current of 3A for 20 hours.

RESERVE CAPACITY (MINUTES)

The Reserve Capacity is the amount of time in minutes that a battery at 25°C can deliver a current of 25 Amps until the voltage drops to 10.5V.

25 Amps represents a typical electrical load on a car under normal running conditions, so the Reserve Capacity gives an indication of the time that a vehicle with a normal electrical load will run with a broken alternator or fan-belt.

Obviously, the more electrical accessories you turn off, the further you can drive the car.

WATER CONSUMPTION

Ca-Sb batteries, compared to Sb-Sb batteries, have less water loss, which ranks them among 'maintenance free' batteries.