https://ebikereviewerdentinygraves.blogspot.com/2024/09/how-do-i-know-if-my-ebike-battery-is-bad.html

Before conducting any tests on your battery, be sure it has a full charge. This is vitally important if you want accurate results from tests conducted. Examine both voltage and current readings; these will show the battery's real-time performance. Check and clean the battery terminals as necessary; corrosion can prevent proper electrical connections, leading to reduced performance and negatively impacting performance.