Battery

A battery, which is actually an electric cell, is a device that produces electricity from a chemical reaction. In reality, a battery can consist of two or more cells connected in series or parallel. A cell consists of a negative electrode ( anode), a positive electrode ( cathode) and an electrolyte. . The electrolyte may be aqueous (composed of water) or non aqueous (not composed of water), in liquid, paste, or solid form.

When the cell is connected to an external load, or device to be powered, the negative electrode supplies a current of electrons that flow through the load and are accepted by the positive electrode. When the external load is removed the reaction ceases.

A primary battery is one that can convert its chemicals into electricity only once and then must be discarded. A secondary battery has electrodes that can be reconstituted by passing electricity back through it; also called a storage or rechargeable battery, it can be reused many times.

In rechargeable battery, the electrochemical oxidation-reduction reactions are reversible at both electrodes. For example, when the battery is recharged, the overall electrochemical reduction reaction at the negative electrode is identical to the electrochemical oxidation reaction that proceeded at the negative electrode when the battery was discharged.

Types of Battery:

There are several types of rechargeable batteries.

  • Nickel-Cadmium Batteries (NiCd)
  • Nickel-Metal Hydride Batteries (NiMH)
  • Lithium-Ion and Lithium-Ion Polymer Batteries (Li-ion)
  • Lead Acid Batteries (Automotive & Sealed Lead-Based)

Among the four type mentiomned above, Lead–acid batteries, are most commonly used in automobiles and inverter industries due to their ability to supply high surge currents . In this category Tubular Batteries are most popular for their ability to charge at fast rate and having long life.

Tubular Battery

Tubular batteries are rugged designs and can be used for high end applications like lifting trucks and in inverters that support heavy loads. They are designed to conveniently operate in areas with rough weather and adverse environmental conditions. Besides, these batteries are useful for applications in areas where ambient temperature range is large. Many of the other battery designs are incapable of operating within such a broad range of temperatures.

A tubular battery is prone to low loss of water and this characteristic makes these batteries more efficient than other batteries. These batteries have been proved to offer good electrical performance in different types of settings. A significant advantage of a tubular battery is its ability to charge at a fast rate. All these characteristics make tubular batteries highly recommended for applications that require high productivity, low maintenance and long life.

Battery Charging

There are three main ways of charging batteries:

  • Trickle charging
  • Float charging
  • Boost charging.

1. Trickle charging

A trickle charger is typically a low-current (500–1,500 mA) battery charger. It is generally used to charge small capacity batteries (2–30 Ah). It is used when there is no permanent load on the battery.

2. Float charging

Float charging is most commonly used for backup and emergency power applications where the discharge of the battery is infrequent. During float charging the charger, battery, and load are connected in parallel. A float charger (also called a storage charger, maintenance charger, or smart charger) will charge a battery at a similar rate as a battery self-discharges, thus maintaining a full capacity battery. However, the main difference between a trickle charger and a float charger is that a float charger has circuitry to prevent battery overcharging.

Float chargers are typically constant-voltage chargers that operate at a low voltage. Operating the charger at a low voltage, usually less than about 2.4 V per cell, keeps the charging current low and thus minimizes the damaging effects of high-current overcharging.

3. Boost charging

Boost charger generally supplied in the combination of trickle cum boost charge or float cum boost charger depending upon the load. It is designed to build the cell voltage from 2V to 2.75 V with minimum current of 10%-15% of the battery capacity.

Boost charging is used when the battery is discharged and we want to build up voltage quickly. In other words if battery water gravity is low, we can increase it by Boost Charging. Boost charger can be operated in constant current mode or constant voltage mode. Boost charging can be applied weekly after discharging cycle of battery set. At the moment of boost charging, voltage applied to battery set is very high compare to rated voltage . If this voltage is allowed to appear across the load, it can damage the equipment connected . So, tapped lower voltage which can be adjusted by dropper diodes is applied to the load.

Maintenance Of Battery

Battery Maintenance is an important issue. The battery should be kept clean. Cable connection needs to be clean as well, and tightened. Many battery problems are caused by dirty and loose connections. Serviceable battery needs to have the fluid level checked regularly and only at a full charge. The fluid level will always be higher at a full charge. Don't overfill battery cells, especially in warmer weather. The natural fluid expansion in hot weather will push excess ePhotovoltaics.