Battery is the used widely as an energy storage device because it is a common power source for many household, commercial and industrial applications. Many challenges are unsolved to characterize and manage the battery and estimation of state of charge (SoC) is one among them.
SoC is the amount of capacity present in a battery and critical for modeling and managing batteries. If SoC is 100% then it is a full battery and if SoC is 0% then it is an empty battery.
SoC controls charging and discharging process of the batteries. A good SoC estimation has various advantages like longer battery life, battery performance and increased reliability of battery pack. There are many methods to determine SoC and few methods are Coulomb counting, Voltage estimation and Impedance measurement method. The aim of SoC algorithm predicts the capacity accurately.
The aim of this SOC Estimation of Rechargeable Batteries project is to estimate the SoC and remaining runtime of a rechargeable battery to overcome the drawbacks of existing methods. The method proposed is based on renowned Coulomb Counting technique and predicts the SoC by Coulomb Counting method and the method is simple and easy to implement.
An electric battery has more than one electrochemical cells connected in series, parallel, or series-parallel combination. An electrochemical cell delivers electrical energy from chemical reactions facilitates chemical reactions by introducing electrical energy. The important parts of an electrochemical cell are Two half cells, Electrolyte and Electrodes. Batteries are classified into Primary (or) Disposable Batteries and Secondary (or) Rechargeable Batteries.
Conclusion:
With the importance of battery in the automotive industry and the energy sector, it develops accurate algorithms for SOC estimation. SoC is estimated by Coulomb Counting method with the battery model and a PI controller. The proposed method has estimating SoC accurately when there is an error to determine initial SoC and flaws in current measurement.
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