If you’ve 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 you’re watching thanks to the miracle of electricity, electricity we’ve
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.
They’re 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.