In batteries, one pole has much more electrons than one other a single. The pole with a lot more electrons is claimed to have a damaging polarity. The pole with much less electrons then has a optimistic polarity. Any time you require extra power than your vehicle's USB ports can https://full-copper-ceiling-fan66530.frewwebs.com/27278929/5-tips-about-aircraft-power-systems-you-can-use-today