| Word | Description |
| E | volt |
| Electricity | The flow of electrons through conductive materials and devices. |
| Electrode | A conductor used to establish electrical contact with a nonmetallic part of a circuit |
| Electrolysis | The chemical process that breaks down the water in the electrolyte, releasing hydrogen from the cathode and oxygen from the anode. |
| Electrolyte | The dilute solution of approximately 25% sulfuric acid (H2SO4) and 75% water by volume in a lead-acid battery, it conducts electricity required for the battery to supply energy. A lead-acid battery may have a liquid, gelled or immobilized electrolyte. |
| Electromechanical | Of, relating to, or being a process or device that converts electrical energy into mechanical movement. A starter motor and an alternator are electromechanical devices. |
| Electromotive Force (EMF) | voltage |
| Electron | A negatively charged particle that orbits the nucleus of an atom. |
| Element | In a battery, a set of positive (+) plates and negative (-) plates along with separators. |
| EMF | electromotive force, which is another term for voltage |
| Energy Density | The ratio of a battery's energy-delivery capability to its weight or volume, measured in watt-hours per kilogram or watt-hours per cubic centimeter. |
| Equalizing Charge | A charging method that equalizes the specific gravity or voltage levels of individual cells in a battery or a group of batteries connected in series. |