Ad hoc announcement pursuant to Art. 53 LR

• Audited 2024 results are consistent with the unaudited preliminary figures published on April 30, 2024.
• Consolidated income reached CHF 18.4 million in 2024, with customer revenue rising to CHF 17.4 million, up from CHF 5.3 million in the first half of the year.
• Net loss reduced to CHF 67.7 million, representing a 4% improvement from the CHF 70.5 million loss reported as of December 31, 2023.
• Balance sheet strengthened, increasing from CHF 106.0 million in 2023 to CHF 109.0 million in 2024.
• Capital structure enhanced on July 10, 2024, through the conversion of CHF 84.7 million of debt into equity. An additional CHF 18 million is expected to be converted, subject to shareholder approval.
• The Company published its second Environmental, Social, and Governance (ESG) report detailing progress made in 2024 on emissions (Scopes 1–3), circularity (12R strategy), regulatory alignment (SFDR, CSRD, EU Battery Regulation), and the integration of ESG into operations, governance, and culture.

YVERDON-LES-BAINS, Switzerland, June 30, 2025 – LECLANCHE SA (SIX: LECN), one of the world’s leading manufacturers of industrial heavy-duty batteries, today announces its results for the full year ending December 31, 2024 and provides a funding update.

Summary of 2024 Financials

In 2024, Leclanché reported consolidated income of CHF 18.4 million, in line with the previous year. Customer revenue reached CHF 17.4 million, a strong recovery from CHF 5.3 million in the first half of the year. Despite overall revenue stability, the Company continued to acquire new customers and deepen relationships with strategic partners, demonstrating its ability to perform under challenging conditions. The operating loss narrowed to CHF (52.7) million, compared to CHF (65.7) million in 2023, reflecting effective cost management.

The Company’s net loss has decreased to CHF 67.7 million, marking a 4% improvement from the            CHF 70.5 million loss reported on December 31, 2023.

The Company demonstrated financial stability with a strengthened balance sheet of CHF 109.0 million as of December 31, 2024, up from CHF 106.0 million a year earlier. On July 10, 2024, LECLANCHE SA strengthened its capital structure by converting CHF 84.7 million of debt into equity. This was followed by two additional debt-to-equity conversions in March 26 and April 28, 2025, totaling CHF 25.4 million, together representing key milestones in reinforcing the Company’s financial resilience.

Funding Update

In addition, Leclanché secured a financing comfort letter with its long-standing majority shareholder, for an amount of up to CHF 40 million available until August 31, 2025. Of this amount, CHF 18 million is planned to be converted into equity through an ordinary capital increase, subject to shareholder approval at the next Annual General Meeting. This conversion will directly address LECLANCHE SA’s negative equity position as of year-end 2024.

Leclanché is making strong progress in its planned strategic collaboration with Pinnacle International Venture Capital (Pinnacle) for a transformative investment of up to CHF 360 million, expected to be disbursed in the second half of 2025. Following the successful completion of the due diligence announced on February 7, 2025, Pinnacle has taken the next proactive step by engaging a leading consulting firm to conduct an engineering review of Leclanché’s upcoming 2 GWh factory in Willstätt, Germany, and to validate the business plan. The project is advancing smoothly and remains fully on track, marking a significant milestone toward scaling Leclanché’s industrial footprint and long-term growth.

The Company is poised for strong expansion, supported by a robust five-year business plan and an expanding pipeline fueled by high-potential opportunities across its three core markets: marine, railways, and special road vehicles.

Sustainability Report

Leclanché is proud to present its second Sustainability Report, showcasing progress made in 2024 toward strategic Environmental, Social, and Governance (ESG) alignment. The report highlights strong ESG progress in 2024, including updated Greenhouse Gas (“GHG”) emissions data (Scopes 1, 2, and 3) and integration of ESG principles into its ISO-certified systems. The company is expanding its sustainability framework from the 6R (typically includes Reduce, Reuse, Recycle, Recover, Redesign, Remanufacture) to a comprehensive 12R strategy, covering circularity, value chain responsibility, and emissions reduction, while aligning with key regulations like Sustainable Finance Disclosure Regulation (SFDR), Corporate Sustainability Reporting Directive (CSRD), European Battery Regulation) for phased implementation through 2035.

A cross-functional initiative was launched to foster a sustainability-driven culture and strengthen stakeholder engagement. Leclanché’s PFAS-free and water-based battery technologies support environmental goals and anticipated regulations. In 2025 and beyond, the focus will be on executing department-level 12R action plans, enhancing sustainability metrics, and accelerating decarbonisation, reinforcing its commitment to transparency, innovation, and long-term value creation.

Pierre Blanc, Group CEO of Leclanché said: “Building on the resilience and innovation that defined our journey through 2024, our team remains energised and deeply committed to delivering exceptional value and customer satisfaction. We are firmly on course, with strong momentum in our strategic initiatives and a growing pipeline that signals a promising future. Our sustainable and fully integrated European production capabilities continue to set us apart, strengthening our competitive edge.

We are sincerely grateful to our investors for their continued trust and support. In 2024, we maintained stable revenues compared to 2023 and achieved significant growth in firm orders, especially within our core E-Mobility markets. Leclanché SA is confidently advancing on a path of innovation and sustainable growth, laying a strong foundation for the exciting opportunities that lie ahead.”

Annual General Meeting

The Company will hold its Annual General Meeting on the 5^th of August 2025 and will publish the invitations to the Annual General Meeting in due course.

For more information, write to info@leclanche.com or visit www.leclanche.com.

Full financials as well as the sustainability report can be accessed using the following link https://www.leclanche.com/financial- reports/.

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About Leclanché

Leclanché is a world leading provider of low-carbon footprint energy storage solutions based on lithium-ion cell technology. Established in 1909 in Yverdon-les-Bains, Switzerland, Leclanché’s history and heritage is rooted in battery and energy storage innovation. The company’s Swiss culture for precision and quality, together with its production facilities in Germany, make Leclanché the partner of choice for companies seeking the very best in battery performance and who are pioneering positive changes in how energy is produced, distributed and consumed around the world. Leclanché is organised into three business units: energy storage solutions, e-Mobility solutions and specialty battery systems. The company currently employs over 350 people with representative offices in eight countries around the world. Leclanché is listed on the Swiss Stock Exchange (SIX: LECN).

SIX Swiss Exchange : ticker symbol LECN | ISIN CH 011 030 311  9

Disclaimer

This press release contains certain forward-looking statements relating to Leclanché’s business, which can be identified by terminology such as “strategic”, “proposes”, “to introduce”, “will”, “planned”, “expected”, “commitment”, “expects”, “set”, “preparing”, “plans”, “estimates”, “aims”, “would”, “potential”, “awaiting”, “estimated”, “proposal”, or similar expressions, or by expressed or implied discussions regarding the ramp up of Leclanché’s production capacity, potential applications for existing products, or regarding potential future revenues from any such products, or potential future sales or earnings of Leclanché or any of its business units. You should not place undue reliance on these statements. Such forward-looking statements reflect the current views of Leclanché regarding future events, and involve known and unknown risks, uncertainties and other factors that may cause actual results to be materially different from any future results, performance or achievements expressed or implied by such statements. There can be no guarantee that Leclanché’s products will achieve any particular revenue levels. Nor can there be any guarantee that Leclanché, or any of the business units, will achieve any particular financial results.

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