Ms. Heather Smiles reports

VOTING NOTICE FOR SHAREHOLDERS AMID CANADA POST STRIKE

Due to the continuing Canada Post strike, the mailing and delivery of Electra Battery Materials Corp.'s meeting materials for its upcoming annual general and special meeting have been disrupted.

Your vote is important. Please cast your vote as soon as possible and ahead of the upcoming meeting. If you have not yet received your voting materials, please take immediate action to obtain your control number and vote on-line. Instructions are provided in the attached table.

Alternatively, shareholders may contact Sodali, Electra's proxy solicitation agent, at 1-833-711-5528 or assistance@investor.sodali.com, for support in obtaining control numbers and submitting votes.

The meeting will be held on Oct. 15, 2025, and votes must be submitted by 10 a.m. ET on Friday, Oct. 10, 2025.

"We want to ensure that all shareholders are able to exercise their right to vote despite the disruptions caused by the postal strike," said Heather Smiles, vice-president, investor relations and corporate development. "Partnering with Sodali provides an additional avenue to make the process straightforward, timely and accessible."

As previously disclosed, Electra is currently undertaking a restructuring of its balance sheet to strengthen the company's financial foundation and advance its strategic priorities. As part of this process, shareholder approval will be required for, among other things, the election of the company's board of directors, including the appointments of Gerard Hueber and Jody Thomas, and other resolutions related to completing the company's restructuring.

Electra encourages all registered shareholders to vote promptly to ensure their shares are represented at this important meeting.

About Electra Battery Materials Corp.

Electra is a leader in advancing North America's critical minerals supply chain for lithium-ion batteries. The company is developing North America's only cobalt sulphate refinery in Ontario as part of a phased strategy to onshore critical minerals refining and reduce reliance on foreign supply chains. Electra's strategy also includes battery recycling and the advancement of its cobalt-copper project in Idaho, Iron Creek, one of the only primary cobalt deposits in the United States. Growth initiatives include integrating black mass recycling at its Ontario refining complex and evaluating opportunities for additional nickel sulphate production in North America.

We seek Safe Harbor.