Higher voltage usually means a fuller battery. But this relationship isn't linear. In fact, lithium batteries tend to hold voltage steady for much of their discharge, then drop sharply at the end. 7V reading might suggest 50% charge. or 30%, depending. Cell imbalance in a high-voltage (HV) battery pack might not throw a red flag right away, but it's often the canary in the coal mine for long-term health issues. Left unchecked, imbalanced cells can cause reduced range, premature battery degradation, charging issues, and in worst cases, thermal. What voltage difference could indicate that some cells are not as good as others? The first thing you should worry about the voltage of the cells: If one of them exceeds the max allowed (or recommended) charging voltage, which is usually 4. A 200mV (5% of max. Doctor of Science from Hubei University, Postdoctoral Fellow in Materials Science and Engineering from Central South University. Keeping lead acid much below 2. 1V/cell will cause the buildup of sulfation. In simple terms, it's the force that pushes electrons through a circuit, powering everything from electric vehicles to your smartwatch.
[PDF Version]