Effects of Pulse Current Charging on the Aging Performance of Commercial Cylindrical Lithium Ion Batteries

Abstract

Rapid development of electronic devices, ranging from personal communication devices to electric mobility solutions, has increased demand for energy storage devices not only in the production volume but also in the product functionality. Among many functional requirements including energy capacity, safety, and short recharge time, one of the major limitations is the short charging time while maintaining the designed capacity. However, even with the most updated lithium-ion battery (LIB) technology, it is well known that fast charging with a high current rate would reduce the lifetime of batteries significantly. Recently, among the many approaches to improve the quick charging performance, a pulse current charging method while keeping the total amount of energy has demonstrated a successful fast recharging of LIB without significantly degrading the battery capacity. The essence of the idea is to stop charging in the middle stage to provide a relaxation period instead of continuously charging at a high current rate. In this study, a comparative study between a conventional charging method with 3C current rate (equivalent to 20 min of charging time) and a pulse current charging with 6C current rate (10 min of charging and 10 min of relaxation time) was carried out. While the conventional charging method showed that the capacity was maintained up to about 200 cycles, the pulse current charging method revealed that the capacity was maintained for more than 450 cycles with a Coulombic efficiency of nearly 100%.

Keywords

• li-ion battery
• fast charging
• state of health (SOH)
• solid electrolyte interface (SEI)
• aging
• pulse current charging