Abstract

Lithium-ion batteries are a crucial component in many applications. Battery lifetime must be estimated accurately to prevent rapid degradation, emission of harmful gases, and fatal explosions. Thus, a mathematical algorithm was created to estimate the battery lifetime, ensuring the safety and efficiency of these systems. Once a lithium-ion battery is not able to store at least 75% state-of-health compared to a new battery, the battery has reached its end-of-life, where further use may result in catastrophes. By gathering data on the properties of the battery cell, such as premature temperature anomalies that indicate the start of declining state-of-health and end-of-life, equations that generate curves to accurately estimate the battery lifetime were created. One equation estimates lifetime as a function of average discharge voltage while the other as a function of discharge capacity. It was found that based on 75% of the 1st cycle discharge capacity, the maximum projected lifetime of the current lithium-ion battery is ~2100-4130 cycles. Also, discharge capacity will limit the battery lifetime before average voltage, but the average voltage the battery can deliver drops off significantly faster after a temperature failure. Using experimental data, an algorithm was developed that accurately estimates lithium-ion battery lifetime with greater precision than before.