This video demonstrates how to wire batteries in series and in parallel. Series means connecting a negative terminal of one battery to the positive terminal of another battery to increase the Voltage . A Parallel connection on the other hand, means connecting "like" (Positive to Positive and Negative to Negative) terminals of batteries together. This does not increase the voltage, but it doubles the AmpRating or Runtime. The video demonstrates how to get 24 and 36 volts from a series of 12 Volt batteries. Visit my website at: http://www.inspectorbots.com or email me at [email protected]