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Various current control algorithms are presented in this paper to prevent vehicle cut-off and increase the range of an electric 2 wheeler based on SoC, battery temperature and motor temperature. At lower SoCs if the current demand is very high there is a possibility of cell voltage hitting the lower threshold voltage leading to cut-off. An algorithm is proposed where current (maximum allowed) derating is done based on reducing SoC, battery voltage and real time throttle demand. Lithium ion cells operating temperature has an upper cap. Rate of increase of battery temperature mainly depends on current demand by motor while the initial battery temperature also depends on ambient temperature. To prevent the battery temperature from reaching the upper threshold a battery temperature based current (maximum allowed) derating algorithm is used. As one algorithm affects the other, this leads to Multi Input Single Output (MISO) system configuration.

With the increase of electric vehicles and lack of standardization in charging infrastructure, the variance in the charger cable length, battery health, and battery capacity can result in unevenness in the charging of lithium-ion batteries (LIBs), which increases the charging time and can deteriorate the battery’s health. Enabling adaptive charging of LIBs can accelerate the commercial application of electric vehicles (EVs). Charging of LIBs is critical and can be optimized to curtail the effective charging time. In this paper, a multistage adaptive charging strategy is presented for LIB-based EV applications to boost the SOC of the battery system in the shortest time. In the proposed charging strategy, initially, multiple pre-charge CC stages are employed to bring the battery out of the deep discharge state and to simultaneously calculate the resistances of the harness (line resistance), and the battery.

Battery packs used in Electric Vehicles (EVs) pose significant safety risks and can incur additional costs and downtime when facing extreme conditions such as thermal and undervoltage hard cut-off. This article emphasizes the importance of implementing thermal and voltage based derating techniques to ensure the safe operation of battery packs. Thermal derating controls the maximum allowed battery current to prevent thermal runaway along with maintaining the health of the cells. While voltage derating prevents cut-off at low SOC regions by managing the cell voltage operating range through real time calculation of DCIR based voltage drop. By adopting these methods, battery packs can operate more safely and reliably in various environment conditions, which is essential in many applications.