Abstract
The battery needed to store electricity is an essential element of a photovoltaic energy production system. The place where this system element is located, during its operation, will thermally influence the way the battery works. The specialized literature presents studies on the influence of temperature on the electrical working capacity of the battery, but through this scientific paper we want to study a concrete case of a LiFePO4 battery and quantify the influence of temperature differences in the working space on the differences in the energy capacities generated by the same battery. The experimental setup allowed recording the temperature of the space where the battery is placed for a long time, so we ensured that the temperature of the battery is approximately equal to that of the working space, just like in a real case of a photovoltaic system. The monitoring of the electric power of the battery in operation was carried out only during its discharge, by imposing a constant discharge current simultaneously with the recording of the voltage at the battery terminals throughout this cycle. At the end of the experiments, we associated the average temperatures during the discharge cycles with the average powers discharged by the battery in each thermal frame. The quantification was achieved by relating the power differences generated to the temperature differences of the different thermal situations experienced. The importance of this study resides into the highlighting of importance to maintain an optimal temperature for the space where the batteries are stored, having as technical effect the maintaining the power’s functioning optimal rate of these. The design of a photovoltaic system must be oriented to a long term calculus regarding power’s rate depending by battery’s working space temperature.