Rio Tinto Ltd (LSE:RIO, ASX:RIO, OTC:RTNTF) is spending nearly $7 billion to acquire diverse lithium company Arcadium Lithium, a sign of confidence in the long-term demand for lithium. Earlier this week, Rio Tinto announced its plan to acquire Arcadium Lithium PLC (NYSE:ALTM, ASX:LTM) in an all-cash transaction valued at $5.85 per share, representing a 90% premium to Arcadium's recent closing price. The deal, which values Arcadium at approximately $6.96 billion in enterprise value, underscores Rio's strateg ...