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  • If youve got a box of old batteries sitting around your house, that’s not the worst

  • thing you could be doing with them.

  • Hello everyone and welcome to another episode of DNews! I’m Amy and youre watching

  • thanks to the miracle of electricity, electricity weve grown accustomed to carrying around

  • with us thanks to batteries.

  • Electricity is what you get when electrons flow through a conductive path like a wire

  • to create a circuit, and batteries play a key role in that circuit.

  • A typical household battery like a AA battery has three basic parts: the negatively charged

  • anode, the positively charged cathode, and the electrolyte typically containing sulfuric

  • acid and water that sits in between them. The cathode and anode are the bits that touch

  • your device via the spring and little nobbly bit in the battery well of, say, a flashlight.

  • Theyre the pieces that close the electrical circuit.

  • The chemical reaction inside a battery causes a build up of electrons at the anode which

  • causes a difference in electrical charge between the anode and the cathode. The electrons want

  • to rearrange themselves and balance out this charge, and so they repel each other to get

  • to where there are fewer electrons. In a battery, that’s the cathode.

  • But the electrolyte in the battery stops the electrons from just hopping over to the cathode,

  • so the only way the electrons can get to where they want to go is to follow a circuit, say

  • though a wire that illuminates the bulb in a flashlight, to get to where they want to

  • go.

  • So why do batteries die? The electrochemical processes within a battery actually change

  • the anode and cathode to the point where they stop supplying electrons. When there are no

  • more electrons, there’s no more power in the battery.

  • Rechargeable batteries work by changing the direction of the flow of electrons; the electrochemical

  • processes happen in reverse, restoring the anode and cathode to their original states

  • and the battery to full power.

  • And here’s the big question: why exactly can’t you throw a non-rechargeable battery

  • away once it’s dead? Batteries are made from chemicals found in minerals of heavy

  • metals, minerals that can be poisonous even in a very small amount. You don't’ really

  • want them sitting around in your house, and you also don't want to throw them away into

  • a landfill where they can pose environmental risks.

  • It’s best to dispose of batteries properly because if it’s done right batteries can

  • be almost or entirely recycled. Recycling a battery is a multistage process. First,

  • the battery is broken apart by a hammer mill such that the lead and heavier pieces fall

  • to the bottom and the lighter, plastic pieces float. The plastic pieces are washed, dried,

  • and sent to a plastic recycler. The lead parts are cleaned and heated in a smelting furnaces

  • until it is molten. That molten lead is then poured into ingot molds and left to cool so

  • the impurities float to the top. Once the impurities are scraped away, ingots are left

  • to cool completely before being remelted and used to produce new batteries. Battery acid

  • is either neutralized and turned into water or processed and converted to sodium sulfate

  • which can then be used in laundry detergent, glass, and textile manufacturing.

  • What to do and where to go varies depending on where you live and usually means asking

  • your local government what to do.

  • So how many of you hold on to your old batteries until you can dispose of them properly?

  • Let us know in the comments below or you can catch me on Twitter as @astVintageSpace. And

  • don’t forget to subscribe for more DNews every day of the week.

If youve got a box of old batteries sitting around your house, that’s not the worst

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