Batteries are devices that store electrical energy. These devices or electrochemical accumulators are used to concentrate, store and discharge electrical energy through reversible redox reactions, making it possible for the total energy stored in a battery to be recharged by electrical sources.
Some batteries serve as a means of storing energy in large quantities, which allows a better use of the electricity supply. Through lithium-ion battery systems such as Quartux's, where electrical energy is stored in the most innovative and efficient way, it is possible to save up to 40% on electricity bills and improve the quality of the energy consumed.
The storage of electrical energy in batteries begins when they are charged and the sulfate and hydrogen ions change position so that energy is stored chemically inside them. That energy is then released in a controlled manner as direct current. Simply put, these devices have the ability to convert chemical energy into electricity.
The structure of the different types of batteries is often very similar: electrochemical cells consisting of two electrodes, one positive (or cathode) and one negative (or anode), which are immersed in electrolytes that allow ions to move between the electrodes so that current flows out of the battery and feeds an electrical circuit.
When a battery is discharged, it is possible to recharge it again by supplying it with an electric current. When it is fully charged, the chemical difference between its cells is restored and the battery is ready to supply the stored energy.
The voltage supplied by batteries is measured in volts (V) and their charge capacity is measured in ampere-hours (Ah). The charge capacity is the amount of electricity a battery can store, as well as the amount of electricity it will later be able to supply when discharged. The energy stored in a battery is measured in watt-hours (Wh), which are obtained by multiplying the charge (Ah) by the voltage (V).
It should be noted that batteries do not always maintain the same charge capacity, as this decreases with time and the number of times they are used. There are factors that directly influence the reduction of its capacity to store energy and shorten its useful life, such as the "memory effect", which occurs when a battery is charged without a previous complete discharge.
Going through a large number of charge and discharge cycles also affects a battery's energy storage capacity, as well as its exposure to high temperatures or very high current demands.
The difference between the different types of batteries lies in the materials from which their electrodes are produced, as well as the variety of their electrolytic substances.
The most commonly used batteries for energy storage are lead-acid, nickel-cadmium, nickel-metal hydride and lithium-ion batteries.lead-acid batteries have lead electrodes that are bathed in a sulfuric acid electrolyte and are among the most economical because they are easy to manufacture. Nickel-cadmium (Ni-Cd) batteries consist of cadmium electrodes and a potassium hydroxide electrolyte. They can be overcharged and withstand a large number of cycles without damage.
P ickel-metal hydride (Ni-MH) batteries have a cadmium anode and a metal hydride alloy cathode. Their capacity is higher than that of nickel-cadmium batteries, although their number of cycles is lower and extreme cold reduces their capacity.
Lithium-ion batteries are composed of electrolytes of cobalt, lithium, oxide and a lithium salt electrolyte. They are one of the best options currently available for energy storage, as their capacity is very high, maintenance is low and lithium-ion waste is easily recycled.
Using lithium-ion batteries has great advantages: they are much more resistant to discharges, have better energy density, do not have the "memory effect", are more efficient for energy saving and have a longer life cycle. While lead-acid batteries have a life cycle of 1500 cycles, lithium-ion batteries last up to 2500 cycles.
Learn more about lithium-ion batteries here.