Global warming is one of our most significant problems, and its impact can devastate humanity. One of the causes of global warming is the transport-related CO2 emission. EVs are believed to be a great solution to this problem. However, there are only a few studies studying this problem. Therefore, this research aims to understand the gap in the CO2 emissions and EV sales/production/users forecast and the correlation between the two variables. This research utilises the ScienceDirect search engine to gather the articles. Out of the 3,877 articles that have been collected, eight relevant papers were selected to be reviewed. All of these articles are related to EVs, with 7 of them discussing the CO2 emissions of EVs, two papers are doing assessments on the life cycle of EVs, three papers are not researching forecasting methods for CO2 emissions, five papers are directly correlating EV with their emissions, and 3 of them are doing comparative studies. Based on the articles that have been reviewed, most research was conducted in China, with four articles published. Most articles do research with minimal data; therefore, the results do not accurately represent the actual conditions of CO2 emissions. Two articles use novel forecasting methods. However, no research has compared these methods to the simpler models, such as the different types of regression models.