The cobalt will be sourced from Glencore's Murrin Murrin nickel-cobalt mine, in Western Australia's north-eastern Goldfields.
Murrin Murrin produced 30,100 tonnes of nickel and 2500t of cobalt in 2021, which was lower than usual due to a shutdown and maintenance issues.
Glencore said the agreement built on both companies' commitments to create strong, sustainable, and resilient supply chains.
Both companies are members of the Responsible Minerals Initiative (RMI), and Glencore's Murrin Murrin operation is conformant with the OECD-aligned Responsible Minerals Assurance Process.
"We are delighted to announce this collaboration and support General Motors in delivering its electric vehicle strategy," Glencore US cobalt marketer and trader Ash Lazenby said.
"Future facing commodities like cobalt play a pivotal role in decarbonising energy consumption and the electric vehicle revolution. Glencore is already a leading producer, recycler and supplier of these commodities, which underpin our own ambition of achieving net zero total emissions by 2050."
GM has a goal to have capacity to build one million electric vehicles in North America by the end of 2025.
"GM and our suppliers are building an EV ecosystem that is focused on sourcing critical raw materials in a secure, sustainable manner," GM vice president, global purchasing and supply chain Jeff Morrison said.
"Importantly, given the critical role of EVs in reducing the carbon footprint of the transportation sector, this agreement is aligned with our approach to responsible sourcing and supply chain management."