Ms. Heather Smiles reports

ELECTRA UPSIZES AT-THE-MARKET OFFERING

Electra Battery Materials Corp. has upsized its previously announced at-the-market offering program pursuant to which the company may offer and sell, at its discretion and from time to time, through H.C. Wainwright & Co. LLC, common shares in the capital of the company having an aggregate offering price of up to $25-million (U.S.). The ATM was established pursuant to an at-the-market offering agreement entered into with Wainwright and dated June 26, 2025. The $25-million (U.S.) aggregate offering amount includes the amount of sales previously made by the company under the ATM agreement pursuant to the company's prospectus supplement dated Dec. 11, 2025, covering sales having an aggregate offering price of up to $5.5-million (U.S.).

The ATM is being made in the United States pursuant to a registration statement on Form F-3 (file No. 333-288364) filed under the Securities Act of 1933, as amended, with the Securities and Exchange Commission, and declared effective by the SEC on Dec. 11, 2025, including the prospectus contained therein, together with the prospectus supplement filed with the SEC on Feb. 20, 2026.

Sales of common shares under the prospectus, if any, will be made in transactions that are deemed to be an at-the-market offering as defined in Rule 415(a)(4) under the securities act, including sales made directly on or through Nasdaq Capital Market. The common shares will be distributed at market prices prevailing at the time of sale. As a result, prices for the common shares may vary as between purchasers and during the period of distribution. No common shares will be sold in the ATM on the TSX Venture Exchange or any other trading market in Canada.

The company intends to use the net proceeds from the ATM for working capital and general corporate purposes, which may include expenditures related to the commissioning of its Ontario, Canada, sulphate refinery. Based on the company's current operating plan and assumptions, it believes that its existing cash, cash equivalents and other sources of liquidity, which may include debt financing provided by government entities, will be sufficient to finance the refinery's planned mechanical completion; however, such plans and assumptions are subject to change.

You can review the company's SEC filings, the registration statement and the prospectus by accessing the SEC's Internet site.

About Electra Battery Materials Corp.

Electra is a leader in advancing North America's critical mineral supply chain for lithium-ion batteries. Currently focused on developing North America's only cobalt sulphate refinery, Electra is executing a phased strategy to onshore critical mineral refining and reduce reliance on foreign supply chains. In addition to establishing the cobalt sulphate refinery, Electra's strategy includes nickel refining and battery recycling. Growth projects include integrating black mass recycling at its existing refining complex, evaluating opportunities for cobalt production in Becancour, Que., and exploring nickel sulphate production potential in North America.

We seek Safe Harbor.