#1ADVENT Acquisition of UltraCell, LLC February 22, 2021 NEXT GENERATION FUEL CELL TECHNOLOGY#2Cautionary Note Regarding Forward-Looking Statements This presentation includes forward-looking statements. These forward-looking statements generally can be identified by the use of words such as "anticipate," "expect," "plan," "could," "may," "will," "believe," "estimate," "forecast," "goal," "project," and other words of similar meaning. These forward-looking statements address various matters including Advent's acquisition of UltraCell and the impact of such acquisition on Advent including, among others, statements concerning the potential benefits, strategic plans and business expectations associated with the acquisition. Each forward-looking statement contained in this press release is subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statement. Applicable risks and uncertainties include, among others, the successful execution of the plans described in this presentation; and the risks identified under the heading "Risk Factors" in the definitive proxy statement / prospectus included in the Registration Statement on Form S-4 filed with the SEC on January 20, 2021, as well as the other information we file with the SEC. We caution investors not to place considerable reliance on the forward-looking statements contained in this presentation. You are encouraged to read our filings with the SEC, available at www.sec.gov, for a discussion of these and other risks and uncertainties. The forward-looking statements in this presentation speak only as of the date of this presentation, and we undertake no obligation to update or revise any of these statements. Our business is subject to substantial risks and uncertainties, including those referenced above. Investors, potential investors, and others should give careful consideration to these risks and uncertainties. Market & Industry Data In this presentation, Advent relies on and refers to information and statistics regarding industry data. Advent obtained this information and statistics from third-party sources, including reports by financial data firms and other firms. Advent has supplemented this information where necessary with information from discussions with its own internal estimates, taking into account publicly available information about other industry participants and Advent's management's best view as to information that is not publicly available. Such information has not been subject to any independent audit or review. To the extent available, the industry, market and competitive position data contained herein has come from official or third party sources. Third party industry publications, studies and surveys generally state that the data contained therein has been obtained from sources believed to be reliable, but that there is no guarantee of the accuracy or completeness of such data. While Advent reasonably believes that each of these publications, studies and surveys has been prepared by a reputable party, neither Advent nor any of their respective directors, officers, employees, agents, affiliates, advisors or agents, have independently verified the data contained therein. In addition, certain industry, market and competitive position data contained herein come from Advent's internal research and estimates based on the knowledge and experience of Advent's management in the markets in which Advent operates. While Advent reasonably believes that such research and estimates are reasonable, they, and their underlying methodology and assumptions, have not been verified by any independent source for accuracy or completeness and are subject to change. Accordingly, reliance should not be placed on any of the industry, market or competitive position contained in such information and no representation or warranty (express or implied) is given that such data is correct or complete. www.advent.energy ADVENT 2#3Transaction Overview Advent Technologies has acquired UltraCell, LLC from Bren-Tronics, Inc. Business Overview Key Transaction Terms Transaction Type: Cash Acquisition of Membership Units Purchase Price: Undisclosed Headquarters: Livermore, CA Founded: 2002 (UltraCell Corp. Assets Acquired by Bren-Tronics, Inc. in 2011) UltraCell HIGH POWER MICRO FUEL CELLS™ AN ADVENT COMPANY Overview of Business: Manufacturer of compact, lightweight and efficient fuel cell based power solutions for portable electronic devices Hundreds of systems, having passed stringent military testing, currently being deployed in the field being used under extreme conditions Leader in the field of methanol-based fuel cell technology Early adopter and current customer of Advent HT-PEM Closing: Deal closed February 18, 2021 www.advent.energy ● ● UltraCell will remain in Livermore, CA maintaining its "Made in USA" label lan Kaye, General Manager and Senior Vice President of Product Development for Advent lan will continue to run the UltraCell business while helping to expand the Advent product line ADVENT 3#4This Transaction Advances Advent's "Any Fuel, Anywhere" Strategy... Any Fuel 7 Multiple liquid hydrogen- carrying fuels can be used from methanol mix to military approved fuel which lowers the cost of ownership and has key infrastructure implications - Anywhere UltraCell systems have been tested and deployed in the most challenging conditions on the planet. From below zero to over 100 degrees F, these systems work in any condition www.advent.energy 67% VOL CH3OH Tahoe City -12C SATURDAY SUNDAY VERBLY TUESDAY UltraCell KRT 75 Fuel Tank AA ə 8.53 PM WEDNESDAY • THUPADEY . 9° 30 33° 1 36" 44° 46° 46 TIPU 50-70% VOL CH3OH Blue Devil WINDSHIELD WASHER 16 ADVENT 4#5And Positions Advent in Cutting Edge Stack Technology Lead Acid Batteries 759 lbs Smaller, Lighter and More Efficient Leader in Small, Portable Stacks - UltraCell's technology allows 37lb of hydrogen carrying-fuel to replace 759lbs of lead acid batteries on surveillance missions an almost 25x reduction 55W to 1,000W fuel cell stacks can be expanded to many kW for other applications Uses Advent 45-165cm² MEAS Will benefit from next-gen MEAS www.advent.energy PROCELL PROCE PROCE UltraCell: H2-carrying liquid fuel 37lbs M ADVENT#6UltraCell Enhances Advent's Commercial Capabilities Immense Potential For Drone, Portable, Aerospace Transportation & Automotive Markets - US DoD defense customers validate our HT-PEM based technology Off-grid power drives a growing portion of US Department of Homeland Security applications in surveillance & security Three EU based NATO militaries have started detailed pilot trials to plan for larger scale deployments Methane Emissions Reduction solution for Oil & Gas Solution wellheads : Can reduce methane emissions 45% in certain areas (methane has 25-84x effect vs CO2 in global warming) The lightweight technology makes it ideal for commercial remote and portable power markets Portable power generators represent a potential $2.8bn market by 2025* *Based on https://www.reportlinker.com/p05834210/Global-Portable-Generators-Industry.html?utm_source=GNW www.advent-energy.com www.advent.energy FCV ZERO EMISSION#7Advent + UltraCell = Leader in Lightweight Stacks and Systems 01 Advent MEA Inside Breakthrough benefits from next generation Advent MEAS Battery Charger vs. 121 lbs of batteries 3 Gallons of methanol 02 11 Partner Product Expands production capabilities with Advent capital. Made in USA 03 Business Expand internationally through Advent's expanding sales network www.advent.energy 04 Vision Know-how & new team propels aviation & automotive next- generation Advent products ADVENT 7#8ADVENT 33 CTTTT Thank You