Recycling batteries with citric acid
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> Highly efficient recycling process for NCM lithium-ion batteries
>formatting link> > Summary:
> A simple, highly efficient, inexpensive, and environmentally friendly process
> could provide a viable pathway for the sustainable recycling of depleted lithium-ion batteries (LIBs):
> No chemicals beyond citric acid need to be added to leach out and separate
> over 99 % of the lithium, nickel, cobalt, and manganese metals contained in
> NCM batteries.
> The resulting recycled material can be directly converted into NCM electrodes, reports a research team.
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> Link with more info:
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You do get some interesting chemistry with citrates not all of it good for you. Natural fruit acids is not the same as harmless. Oxalic acid of rhubarb leaves and ant stings is really rather nasty.
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Although cute the worry is much more about the metal ions than the acid used to dissolve them. The cobalt chloride pale pink "invisible ink" of our childhood which turns blue when heated is now deemed a carcinogen and all dessicants using it as an indicator were withdrawn around Y2k.Hydrochloric acid will dissolve all of the above metals a lot quicker.