Assessment of Lithium Ferrous Phosphate Battery Cells Under Series Balancing Mode—Performance and Health Behaviours

Electric vehicles have recently gained greater attention across all countries for transportation purposes in on-road and off-road forms due to their supreme performance and clean eco-friendliness status. Lithium-ferrous phosphate batteries are the primary energy storage devices in electric vehicles due to their higher energy density, longer lifespan, and lower self-discharge rate. They also possess several technical advantages, including a wider range of applications, economic affordability, an environmentally friendly nature, and, most importantly, superior electrochemical performance, which makes them a strong competitor to lead acid batteries. In the present study, a performance and health assessment of a lithium ferrous phosphate battery (LFP) pack consisting of 23 cells connected in series balancing mode with a 7360 Wh maximum energy storage capacity has been carried out at various current ranges of operation such as 3 A, 5 A, and 8 A in a typically developed battery management system to estimate their optimized performance and overall health conditions. Further study has been conducted to investigate the characteristics of LFP packs under various power-mode conditions, ranging from 20 W to 750 W. This experimental study revealed that the LFP battery pack exhibits a remarkable state-of-charge capability, achieving 58% charging in a 3.3-h runtime period. A similar decreasing trend was also observed during power-mode operations. Furthermore, the LFP battery pack was fully charged after achieving a 50% State of Charge (SOC) under every current-mode condition, providing reliable outputs under the loading conditions. It is also stated that the state of health of the lithium ferrous phosphate is significantly higher at 92% during the entire investigation, which reflects the good thermal stability of the LFP battery pack for temperature variations from 26 °C to 31 °C. Finally, it is concluded that the LFP could be one of the most favourable energy storage systems due to its longer lifespan and its great affordability in automotive applications.