Current in an electric circuit creates heat when the current overcomes resistance in the wire.

Voltage (V) is the electrical potential difference between two points. Electrons will flow as current from areas of high potential (concentration of electrons) to areas of low potential. Voltage and current are directly proportional in that the higher the voltage applied to a conductor the higher the current that will result.

Splicing is permanently joining two wires together. Splicing can be done with screw-on connectors or wire crimps but the preferred method for splicing is soldering. Soldering takes the most effort but results in a connection that is electrically and mechanically identical to the original wire.

A diode allows current to pass easily in one direction and blocks current in the other direction. Diodes are commonly used for rectification which is the conversion of alternating current (AC) into direct current (DC). Because a diode only allows current flow in one direction, it will pass either the upper or lower half of AC waves (half-wave rectification) creating pulsating DC. Multiple diodes can be connected together to utilize both halves of the AC signal in full-wave rectification.

Connecting the 6 batteries in series multiplies their voltage while keeping their current the same yielding a 90V 20A configuration. Connecting the 6 batteries in parallel multiplies their current while keeping their voltage the same yieleding a 15V 120A configuration. Using a series-parallel connection, 3 batteries can be connected in series and 3 can be connected in parallel resulting in a 45V 60A configuration.