The Lithium Ion Batteries for Electric vehicles need to be managed, otherwise they would deteriorate like those in Mobile phones. The Battery Management System (BMS) is designed to do just that.
BMS Improving fast
Battery Management Systems have improved significantly in the past decade, the early Nissan Leafs’ BMS are considered very poor by today’s standards.
Different manufacturers use different approaches to Battery management, but the objective is to prolong the life of the battery. The main concern is when charging approaches 100% charge, as too long at 100% degrades the battery. To reduce degradation the system ‘Ramps down’ the charging rate, consequently after around 80% charge the battery charges at a much slower rate.
Understanding how charging rate varies over the period plugged in
0 to 100% charging
Unless a full charge is required it’s better for the battery not to charge past 80%. Consequently, although 0 to 100% charging times may be accurate they may not be helpful. Keeping within 20 – 80% is recommended by Topping-up.