Charge – the process of putting electrical energy into a battery where it is stored as chemical energy. This involves passing an electrical current through the battery which causes changes to its components. In a Lithium Ion battery, for example, charging causes lithium ions to move from the positive cathode…
Capacity – the amount of electrical energy available from a battery or cell of a given voltage measured in amp hours or milliamp hours. A milliamp hour is 1000th of an amp hour. 1 Ah = 1000 mAh What creates a battery’s capacity? Batteries are made up of cells (or…
Connector – some batteries or battery packs do not have visible positive and negative terminals. Instead they have positive and negative wires that are connected to the battery or battery pack internally at one end and to a plug at the other. The plug is the connector. Different devices require different…
Charge Voltage – the amount of battery voltage when the battery is fully charged or the voltage available at any given point during the charging process. Various sources describe charge voltage in two different ways, so we’ll cover both here. Voltage when the battery is fully charged For this explanation…
Float Voltage – the voltage a battery should be kept at if used in a standby application (such as emergency lighting). To understand float voltage its important to know: The voltage of a battery decreases as it is discharged and increases as it is charged All batteries gradually discharge over…
Discharge Voltage – the amount of battery voltage available at any given point while the battery is discharging. The voltage of a battery gradually decreases as it discharges. The rate of this decrease depends on the device it is powering and the battery chemistry. The voltage in sealed lead acid…
Negative Terminal – the terminal from which electrons flow in the external circuit when the battery discharges. Marked by a ‘–’ (minus) sign and/or the color black. See terminals for more details, images and diagrams of the various terminal types in use.
Overcharging – continuing the charging of a battery even after it has reached 100% capacity / State of Charge or supplying more energy to a battery than it can convert into stored energy over a given period of time. What’s actually happening during the charging process? Electrical energy is being…
Polarity – the settings of the charges found at the terminals of the battery – which terminal is positive and which terminal is negative. The positive terminal is usually marked with a ‘+’ symbol and/or the color red while the negative terminal is usually marked with a ‘-‘ symbol and/or…
Parallel Batteries – A group of batteries or cells with all terminals of the same polarity wired together – i.e. positive connected to positive and negative connected to negative. In this set up the batteries capacity (amp hours or milliamp hours) is increased, but the voltage remains the same as…
