Lithium batteries are the heart of every electronic device, from laptops and smartphones to electric vehicles or renewable power stations. They introduced a plethora of benefits like high energy density and durability without the need for maintenance that other technologies lead acid batteries required. However, battery operation must be constantly monitored, as it suffers from increased temperatures caused by increased charging/ discharging currents, high voltage and peak loads. These operating conditions lead to lithium deposition and partial electrolyte decomposition, limiting the total capacity (State of Health) or even leading to a possible breakdown. Hence, consistent monitoring of power, temperature and operating voltage is essential to ensure maximum lifespan without risking safety. In this paper a compact module consisting of 3 lithium batteries at 3.7V is introduced. Each battery has its own NTC thermistor and voltage sensor installed at the negative electrode, while the total Bus voltage, current and load voltage are monitored as well. The output power and other parameters are depicted through the Grafana Dashboard for quick access and graphical representation. The goal of this paper is to check how the variations of voltage and cell temperature, depending on the power required, affect battery health ensuring battery operating conditions stay within manufacturer limits to avoid damage.