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A new waste mountain?

Remember the days when most battery-powered things would send you broke?

Yes, over a lifetime I must have spent thousands of dollars on AA, C and D sized primary cells (incorrectly referred to as "batteries") for the myriad of portable electrical and electronic devices I've owned.

Time was that the only chemistry available was the good old carbon-zinc 1.5V cells which had a very limited shelf and in-service lifetime. In fact, as a youngster I would be over the moon if I managed to get my hands on one of those huge number 6 cylindrical cells that were seemingly used in telephone systems. These things would last almost forever in my little experiments and delivered enough current to make fuse-wire glow red hot.

The metal shell of these batteries was zinc which made them a great source of that metal for further experimentation with my chemistry hat on.

The carbon rods that could be salvaged from these cells could be ground up to make a key component of home-made gunpowder or sharpned and used with a car battery to produce a powerful carbon-arc light source.

Over the decades, billions or perhaps trillions of these simple, cheap and ubiquitous cells must have been made, used and thrown away.

Fortunately, at all stages of that process, these are a very safe chemistry.

Carbon is relatively inert and neither the zinc case nor the manganese-based electrolyte component pose no real toxic threat to the environment so disposal in land-fills has been an acceptable way to get rid of them so far.

The arrival and affordability of superior rechargable technologies has meant that we are no longer slavishly forking out fists-full of money to keep our portable devices working. As a result, I don't buy nearly as many primary cells as I used to and any new device you buy today is probably going to have a built-in rechargeable battery and a USB-C charging socket.

Unfortunately, many more modern battery chemistries are far from as environmentally benign.

Perhaps the worst would have been the nickel-cadmium battery. Although nickel isn't too bad, cadmium is a nasty metal that can have pretty severe effects on any biological organism. Fortunately nickel-cadmium chemistry has been largely replaced by others with superior performance.

Of course the preeminent battery technology these days is the lithium-ion cell.

Lithium-ion batteries come in many variants and while some, such as lithium iron phosphate, are not too much of an environmental risk but others contain things such as cobalt compounds which are not so life-friendly.

The problem we are about to face is that there are just so many lithium-ion cells in service right now that there is going to be a huge issue with disposal.

Recycle them?

Well from what I've been able to determine, the actual material value in many of these lithium-ion chemistries is not worth the cost of recycling. Why spend $1 to retreive $0.20 worth of raw materials?

I know a few of you will be tapping away on your keyboards right now to remind me that the cells out of EVs can be repurposed for use as domestic grid/solar-connected storage batteries and that will give them a few years more of usefull life but the reality is that eventually, they will die and at that stage, whenever it is, we'll have to do something with them.

Already it is forbidden to throw lithium cells in your domestic waste and we've seen a growing number of incidents where rubbish trucks have caught fire because someone has ignored the ban and during the compacting process a partially charged cell as combusted. So where do we send these old cells when their useful life is ended?

I'm sure that dedicated collection points will help but where to after that?

Yes, there are recycling technologies, most of which seem to involve dumping them into a conductive solution for a few hours (to make sure they're fully discharged) then grinding them up and dissolving the resultant powder using acids. Attempts are then made to extract the valuable salts and purify them.

However, this is itself an energy-intensive operation with significant environmentally harmful waste products -- so are we better off simply dumping those cells somewhere safe?

Unfortunately I believe the magnitude of this disposal problem will grow very quickly and I don't think we are going to be ready in time. Everyone is far to busy focusing on developing battery tech and manufacturing whilst conveniently ignoring the elephant in the room.

Carpe Diem folks!

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