Li2O-forbruk i EV-batterier

Fra 'How much Lithium does a Li-Ion EV battery really need?'

Lithium Carbonate Purification
Another factor that must be allowed for is the processing yield to purify raw technical grade Lithium Carbonate into purified low sodium (99.95%) Lithium Carbonate required for the manufacture of batteries. The technical grade Li2CO3 produced from Atacama contains about 0.04% Sodium (Na). This has to be reduced to below 0.0002% Na for use in batteries. In some cases ultra high purity 99.995% Lithium Carbonate is required. While yields of over 80% are possible on a laboratory scale, this is more difficult to achieve industrially particularly as purity control requirements increase. 70% may be a more realistic yield figure to use.

A real world EV LiIon battery will provide nominally some 25% of the theoretical energy capacity or 70 – 120 Wh/kg instead of 410 – 450 Wh/kg. This translates into a Lithium requirement of at least 320 g of Lithium (1.7 kg LCE) per kWh of available capacity. In addition, Lithium has to be added to this for the electrolyte, irreversible capacity loss and capacity fade. EV batteries will be 25% oversized to account for capacity fade. Then allowance has to be made for processing yields of an estimated 70% from the raw technical grade Lithium Carbonate plus inevitable losses in the use of high control purity Lithium Carbonate in the manufacture of the battery components themselves. LiMPO4 batteries operate at lower voltage than LiMO2 and therefore induce a further increase.

If one therefore allows 400 g of Lithium (2.1 kg LCE) per battery kWh with a 70% processing yield to produce that, an initial 3 kg of raw technical grade Lithium Carbonate will be required per kWh of final usable battery capacity.

At 3 kg raw technical grade LCE per kWh, current global production of some 100,000 tonnes raw LCE would be sufficient, if available, for some 2 million 16 kWh batteries per year. Even at an optimistic 2 kg LCE per kWh assuming very high purity yields, production would be sufficient for only 3 million 16 kWh PHEV batteries per year