Since this is the first mass market automotive application of a lithium battery, Mercedes and Continental are being extra careful. The battery is designed to last a minimum of 10 years and 100,000-150,000 miles so Continental has developed a sophisticated monitoring system to make sure that it operates within normal operating parameters. Each individual cell is monitored to keeps loads balanced and ensure even charging and discharging. Continental had to develop special processes to weld the copper bus bars that act as cell interconnects. The whole battery is enclosed inside of a laser-welded stainless steel case. The initial production capacity of the factory is 15,000 units a year and that can easily be doubled.