 The International Electrotechnical Commission, IEC, and the International Organization for Standardization, ISO, have been working together to develop standards for lithium ion batteries. These standards include testing procedures for determining the charge and discharge capabilities, power performance, and life cycle of the batteries. A new method was also developed to determine the life cycle of a battery in relation to its depth of discharge. This article was authored by Yuri VanMierlo, Peter VanDenBosche, Omar Heggazi, and others.