
Ask HN: What do we do with used electric cars batteries? - lamentus
Hello HN!
I am looking for information about what do we do with used electric cars batteries. Do we recycle them or we just put them on garbage dump? Thank you
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speedgoose
The first step is to fix other battery packs.

Usually when an eletric car battery goes wrong, only a module do so and you
can replace the broken module and balance everything. So you can make good
battery packs using bad battery packs.

Second step is to use the battery for something else that is less critical on
energy density. If a battery pack holds only 50% of its original capacity,
it's not very nice in a car but you can still use it for energy storage at
home for example. Also if you have a 100kWh pack, you usually need 110kWh to
"fill" it. But if for some reasons this battery pack deteriorates to 50kWh,
you will need 55kWh to fill it. In other words, an old battery pack do not
waste energy compared to a new one. It just represents a lower potential of
energy. Of course you have things such as internal resistance so the
efficiency may vary over time, but it's not an efficiency disaster.

Last solution is to recycle. It's not very developed because the amount of
eletric car batteries to recycle isn't that high yet. Today a solution used at
least in France is quite simple, you burn the batteries in a large oven and
you keep the melted metals. You have to filter the fumes and the cobalt is
lost. But you get lithium, that may be more expensive than lithium extracted
from a mine. Another process I heard about is about crushing the batteries and
filtering them instead of burning them.

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boznz
Sell them, People doing EV car conversions and home powerwalls generally snap
them up as soon as they are listed. I doubt many go to landfill or re-cycling

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calabroa
Yeah they're great for grid stabilization and battery storage projects.

