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      06-01-2021, 04:15 AM   #577
M5Rick
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Quote:
Originally Posted by GrussGott View Post
Well, good news then! Cobalt isn't required for lithium-ion batteries and soon won't be used in most average vehicles including Tesla ... it works likes this:

The battery has 3 pieces, the anode, cathode, and electrolyte:

▸ The anode stores power from the charger, so the materials determine charging time and, to a much less degree, range

▸ The cathode is where the power flows to from the anode during use so the materials determine the range & performance; ~40% of the cost is here.

▸ The electrolyte is a liquid salt solution that facilitates the power transfer between the terminals (the anode & cathode)


So back to the spendy cathode ... VW, as an example, is planning on 3 different chemistries to support different classes of vehicles. Right now, most automotive batteries, to your point, are NMC (nickel, manganese, cobalt) though Tesla uses nickel, aluminum, cobalt.

Beyond the other things you stated, cobalt is $$$ and that's why that 40% of cost is in that cathode ... so VW is going to use other chemistries:

▷ FePO4 - iron phosphate, which gets rid of NMC altogether! Tesla is working on this too - the upside is WAY cheaper & can handle way more charge cycles ... but the downside is ~10-20% range/performance loss. Though for a low-cost commuter care who cares and more charge cycle durability in a commuter is a good trade-off!

▷ NM Get rid of the cobalt, cut the nickel down to minimal and use mostly manganese. VW will use this for mid-range vehicles and claims a 30% cost reduction with no compromises in terms of performance or range.

▷ NMC This one will be for niche low-volume heavy duty and high performance vehicles, but with a lot more nickel to increase the range & power.

On the anode side, VW, Tesla, and others have synthetic graphic which is cheaper and allows for fast charging (this is why Taycans can charge from 5% to 80% in 20 minutes)

Beyond that EVERYONE is working on solid state batteries, i.e., no electrolyte - beyond all kinds of other benefits, safety is a big one because current batteries can occasionally develop dendrites that are like little spikes that short circuit the battery and then

I like pictures so here's one from a QuantumScape presentation that shows the relative benefits of solid state LIons vs other chemistries:



The net-net is, I don't think cobalt will be used in any large quantities for automotive batteries going forward, and you can see a time where very little if any would be used.
Good news then as far as Cobalt is concerned which brings my attention to next can o' worms in EV self drive cars and crashes when things go wrong demonstrated by the latest double fatality with a Prius going into a tree and the occupants burnt when the batteries ignited.
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