Inside of battery-operated devices requiring the batteries to be stacked end-to-end, how come the batteries in the middle don’t quickly neutralized when the electrons from the negative cell flow through the positive?


For anyone that doesn’t know, and I hope I’m not relaying incorrect information, a regular voltaic battery like a Duracell or Energizer has a negatively charged end where electricity flows through the device it’s being used for, powering the device, before completing its circuit to the positively charged end and the charges cancelling out/neutralizing. The battery is dead when the there’s little to no charge difference between the cells.

When batteries are stacked end-to-end in like a flashlight, won’t the negatively charged ends in the middle flow through the positive end of the next battery? Why aren’t they more quickly neutralized then?

In: Physics

Electrons in a battery flow from negative to positive. So when the positive end of one battery connects to the negative end of another the electrons are flowing in the same direction so they add their voltages together and keep flowing.

Electricity is the flow of electrons and electrons are negatively charged. So a positive charge on a battery just means there are holes that can accept electrons. There isn’t actually any particle that is positively charged pushing out the positive end of a battery, it’s just missing electrons and ready to accept more.

when the cells are connected they act like one bigger battery. the electrons still move from negative to positive even through other cells. the overall effect is that the last negative end is that much more negative than a single cell.

Imagine if you put three pumps in series, up a hill. All the pumps are only strong enough to lift water 10 feet. The first pump pulls water from the pond and pumps it up 10 meters, where it feeds the second pump, which pumps it up to the third pump, which fills the barrel at the top of the hill, 30 feet higher.

Can you see how each pump does the same work?

This is the situation with batteries in series. Each one pushes the current through them ‘uphill’, with more energy, more pressure, then the next one adds more pressure, until you get to the top of the stack, where you have enough pressure to run your device.

So the bottom battery has its negative at 0v, and the positive at 1.5. The negative of the second cell is attached here, so is at 1.5 too – so the positive will be 1.5 volts higher at 3.0 volts. This is where the the third battery sits, with its negative at 3 volts, and the positive at 4.5. Each battery is in the same condition – with it’s positive end 1.5 volts higher than its negative end. Each battery does the same work – pulling the same current that is flowing through the whole stack and adding 1.5 volts worth of energy to it.