Reliability and Availability Analysis of Lithium-Ion Batteries under Multiple Failures

Energy storage solutions based on lithium-ion (Li-ion) batteries are becoming more popular. These batteries are progressively used because of their competitive performance compared to other battery types. It is an improved battery technology, and the lithium ion is the main factor of its electrochemistry. Li-ion batteries can have a very high voltage and charge storage per unit mass and unit volume, also have several benefits in comparison to other high feature rechargeable battery technologies. There are various applications of Li-ion batteries such as consumer electronics, electric vehicle, and light power industry etc. Li-ion batteries for such type of systems are the main components, which should be safe and reliable throughout the operating lifespan of the systems. The increasing energy density of Li-ion cells (Wh/L) and at the same time the increasing amount of stored total energy in various solutions accentuate the efforts on battery safety and measures to maintain a maximum on safety and reliability. The reliability of Li-ion batteries is directly related to the life and safe operation of electric drive products. For the accurate assessment of the reliability of Li-ion batteries, it is important to build a reliability model considering the dependency among cells for the overall degradation of Li-ion battery packs. This paper presents a broad summary of the reliability assessment of Li-ion batteries under multiple failures. Different reliability measures such as reliability, availability and expected cost have been investigated with the help of Markov process and supplementary variable technique.