Design and Construction of a 72V 20Ah Lithium-Ion BMS-Integrated Electric Vehicle Battery Pack for the Pesut EV.1 Electric Go-Kart

This research aims to design, build, and test a 72 Volt 20 Ah lithium-ion battery pack for the Pesut EV.1 Mahakam Team electric go-kart. The battery pack is designed with a 20S4P configuration using lithium-ion cells, equipped with a Daly 72 Volt 100 Ampere Battery Management System (BMS), and modeled in CAD software. Testing was carried out through three charging and discharging trials to analyze the voltage, current, and temperature parameters during the process. To enable real-time monitoring, visualization, and data logging during go-kart operation, an IoT-based telemetry system was integrated using a microcontroller and dedicated sensors communicating via the MQTT protocol. In addition, thermal simulations were carried out using FEA software. The test results demonstrated stable and consistent battery performance. During the charging process, the voltage gradually increased from 68 V to 84 V with a stable charging current in the range of 5.90 A – 12.37 A, yielding an average absorbed capacity of 21.15 Ah and input energy of 1,612.11 Wh, while the temperature remained between 25.00 °C and 28.50 °C. Meanwhile, during the discharging process, the voltage gradually decreased from 84 V to approximately 68 V, with the discharge current reaching up to 68.7 A and a maximum temperature of 43 °C. However, dynamic discharge capacity calculation using a 30-second logging interval resulted in overestimation errors due to transient current fluctuations, indicating the need for higher sampling frequencies in future evaluations. Simulation results also demonstrated an even temperature distribution and no overheating during operation. The results indicate that the developed battery pack performed reliably under the tested charging and discharging conditions for Pesut EV.1 Electric Go-Kart usage and racing applications.