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Century Lithium Reports Updated Feasibility Study with After-Tax NPV of $4.01 Billion and Operating Costs of $4,389 PER Tonne of Lithium Carbonate FOR the Angel Island Lithium Project, Nevada Feasibility Study Highlights

Economic Studies

TSXV: LCE | OTCQX: CYDVF

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NEWS RELEASE

CENTURY LITHIUM REPORTS UPDATED FEASIBILITY STUDY

WITH AFTER-TAX NPV OF $4.01 BILLION AND OPERATING COSTS OF $4,389 PER

TONNE OF LITHIUM CARBONATE FOR THE ANGEL ISLAND LITHIUM PROJECT,

NEVADA

FEASIBILITY STUDY HIGHLIGHTS

• After-tax NPV (using 8% discount rate) of $4.01 billion based on price assumptions of $24,000 per

tonne (“/t”) for lithium carbonate (“Li2CO3”) and $750/dry metric tonne (“dmt”) for Sodium Hydroxide

(“NaOH”)

• After-tax internal rate of return (“IRR”) of 27.4%

• Integrated patent-pending processing flowsheet, incorporating hydrochloric acid leaching, Direct

Lithium Extraction (“DLE”), chlor-alkali processing, and on-site production of battery-grade lithium

carbonate, validated through four years of pilot plant operations in Nevada

• Large, long-life U.S.-based lithium development project, with Proven and Probable Reserves

supporting a mine life exceeding 60 years

• Economic analysis based on a 40-year production schedule, with planned life-of-mine average

production of approximately 26,500 tonnes per annum (“tpa”) of battery-grade lithium carbonate

• Initial Phase 1 throughput of 7,500 tonnes per day (“tpd”), expanding to 15,000 tpd in Year 5 (Phase

2)

Capital and Operating Costs

• Phase I capital cost of $997 million compared to $1.537 billion in the 2024 Study

• Phase 2 expansion capital of $660 million compared to $651 million in the 2024 Study

• Average operating cost of $22.45 per tonne of mill feed, equivalent to $4,389 per tonne of lithium

carbonate, compared to $8,223 per tonne in the 2024 Study

• Project revenues from surplus sodium hydroxide equivalent to $5,393/t of lithium carbonate

produced. When treated as a co-product credit, this would result in a net operating cost below zero

Mineral Resource and Reserve

• Measured and Indicated Mineral Resources of 1.138 billion tonnes at 966 parts per million (“ppm”)

lithium, containing 5.852 million tonnes lithium carbonate equivalent (“LCE”)

• Proven and Probable Mineral Reserves of 287.65 million tonnes at 1,149 ppm lithium, containing

1.759 million tonnes LCE

February 23, 2026 – Vancouver, Canada – Century Lithium Corp. (TSXV: LCE) (OTCQX: CYDVF) (Frankfurt:

C1Z) (“Century Lithium” or “the Company”) is pleased to announce the results of an updated National

Instrument 43-101 (“NI 43-101”) compliant Feasibility Study (“2026 Feasibility Study”) for its 100%-owned

Angel Island Lithium Project (“Angel Island”) located in Esmeralda County, Nevada, USA.

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The 2026 Feasibility Study incorporates the results of continued metallurgical testing, engineering

optimization, refinement of the mine plan, and updated capital and operating cost estimates for Angel

Island. The study demonstrates strong project economics, including an after-tax net present value (“NPV”)

of $4.01 billion.

No material changes were made to the Mineral Resource or Mineral Reserve estimates used in the “NI 43-

101 Technical Report on the Feasibility Study of the Clayton Valley Lithium Project, Esmeralda County,

Nevada, USA”, dated April 29, 2024 (“2024 Study”) and are used in their entirety in the 2026 Feasibility

Study.

All currency amounts in this news release are expressed in U.S. dollars.

2026 FEASIBILITY STUDY SUMMARY

The 2026 Feasibility Study confirms the technical and economic viability of developing the Angel Island

project as a significant domestic source of battery-grade lithium carbonate in the United States.

Mining is planned as a conventional open-pit operation extracting lithium-bearing claystone

mineralization. Mined material will be processed on-site using hydrochloric acid leaching, solid-liquid

separation, Direct Lithium Extraction (“DLE”), lithium carbonate precipitation, and an integrated chlor-

alkali plant, resulting in on-site production of battery-grade lithium carbonate.

The 2026 Feasibility Study reconfigures Angel Island into a two-phase development plan, consisting of an

initial 7,500 tpd operation with expansion to 15,000 tpd. The third expansion phase contemplated in the

2024 Study was removed, simplifying project execution and reducing overall capital requirements.

Bill Willoughby, President and CEO of Century Lithium commented:

“The results of the 2026 Feasibility Study represent a material improvement. These results were made

possible by Century Lithium’s team who, through many steps of optimization including those at the

Company’s pilot plant, have delivered a more efficient development plan for the Project. In the 2026

Feasibility Study, this streamlined process is reflected in equipment and related infrastructure, importantly

in electrical demand, and is seen in the resulting capital and operating cost estimates.”

CAPITAL AND OPERATING COSTS

A Class 3 capital cost estimate was prepared in accordance with AACE guidelines, and Canadian Institute

of Mining Metallurgy and Petroleum (“CIM”) Best Practices. The updated costs were developed using

second-quarter 2025 data.

• Phase 1 (7,500 tpd) initial capital cost: $997 million

• Phase 2 (15,000 tpd) expansion capital cost: $660 million

Reductions to estimated capital costs in the 2026 Feasibility Study relative to the 2024 Study are

attributable to:

• Elimination of a previously planned third production phase

• Simplification of project scope and installed capacity

• Refinement of the mine scheduling and equipment selection

• Processing flowsheet optimization informed by pilot plant operations

• Updated vendor pricing and construction cost inputs

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Operating costs benefit materially from Angel Island’s planned vertically integrated chlor-alkali facility,

which generates hydrochloric acid and produces surplus sodium hydroxide for sale.

• Average operating cost – Phase 1: estimated $30.59/t of mill feed

• Average operating cost – Phase 2: estimated $22.16/t of mill feed

MINERAL RESOURCES AND MINERAL RESERVES

Mineral Resource and Mineral Reserve estimates used in the 2026 Feasibility Study are unchanged from

the prepared in accordance with NI 43-101 and CIM Definition Standards.

Mineral Resources (inclusive of Mineral Reserves):

• Measured and Indicated: 1.138 billion tonnes at 966 ppm lithium, containing 5.852 million tonnes

LCE

• Inferred: 187.28 million tonnes at 820 ppm lithium

Mineral Reserves:

• Proven and Probable: 287.65 million tonnes at 1,149 ppm lithium, containing 1.759 million tonnes

LCE

• Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability

ECONOMIC ANALYSIS indicates Angel Island remains economically attractive across a wide range of

commodity price and cost assumptions, with lithium price representing the most significant driver of Angel

Island’s value.

Using a base-case lithium carbonate price of $24,000/t and an 8% discount rate, Angel Island generates:

• After-tax NPV: $4.01 billion

• After-tax IRR: 27.4%

• Profitability Index: 4.0

Sensitivity analysis indicates Angel Island remains economically attractive across a wide range of

commodity price and cost assumptions, with lithium price representing the most significant driver of Angel

Island’s value.

NEXT STEPS

Century Lithium will continue to advance Angel Island toward development through submission of plan of

operations, permitting, detailed engineering, and engagement with interested parties as the Project

progresses toward a construction decision. Integral to these key steps are:

• Recent appointment of Cormac O’Laoire, PhD to advise the Company in discussions with potential

downstream partners and offtake interests. The Company continues to make inroads in

Washington DC and Nevada to convey the importance of Angel Island for a secure North American

supply chain.

• Further evaluation of the economic potential for rare earth elements (“REE”) recovery at Angel

Island.

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• Engagement of BMO Capital Markets to assist the Company in its efforts towards securing strategic

interests and development funding.

• Addition, in 2025 to the US Federal Permitting Dashboard for FAST-41 transparency status.

Inclusion to FAST-41 increases the Project’s exposure to federal agencies and stakeholders to

accelerate the permitting process.

SUMMARY OF 2026 NI 43-101 FEASIBILITY STUDY

This summary forms an integral part of this news release.

An NI 43-101 Feasibility Study on the Angel Island Lithium Project was prepared to update metallurgical

results, mine planning assumptions, and capital and operating cost estimates relative to the 2024 Study.

Unless otherwise stated herein, Mineral Resource and Mineral Reserve estimates, geological

interpretations, and environmental and permitting assumptions remain materially unchanged from the

2024 Study.

Property Description, Location, and Tenure

Angel Island is located in Esmeralda County, Nevada, USA, approximately 354 km southeast of Reno. Angel

Island comprises 503 unpatented mining claims (276 placer and 227 lode claims) covering approximately

2,286 hectares, held 100% by Cypress Holdings (Nevada) Ltd., a wholly owned subsidiary of Century Lithium

Corp. Existing royalty arrangements remain unchanged.

Geology, Mineralization, and Deposit Type

Angel Island hosts a large, flat-lying sedimentary lithium claystone deposit within the Esmeralda Formation.

Lithium mineralization occurs primarily within claystone, tuffaceous mudstone, and siltstone units. No

material changes were made to the geological model, mineralization interpretation, or deposit

classification from the 2024 Study.

Exploration, Drilling, Sampling, and Data Verification

The Mineral Resource and Mineral Reserve estimates are supported by 45 drill holes totaling approximately

3,955 meters, completed between 2017 and 2022. Drilling includes conventional core and sonic drilling.

Sample preparation, analytical methods, QA/QC protocols, and data verification procedures remain

unchanged from the 2024 Study and meet CIM and NI 43-101 standards.

Mineral Resource Estimate (Unchanged from 2024 Study)

The Mineral Resource estimate has an effective date of April 29, 2024, and remains unchanged in the 2026

Feasibility Study.

Measured and Indicated Mineral Resources:

• 1.138 billion tonnes at an average grade of 966 ppm lithium, containing 5.852 million tonnes LCE

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Inferred Mineral Resources:

• 187.28 million tonnes at an average grade of 820 ppm lithium, containing 0.817 million tonnes LCE

Mineral Resource Estimate

Domain Tonnes Above

Cut-off (millions) Li Grade (ppm) Li Contained

(million t) LCE (million t)

Measured 858.26 990 0.850 4.523

Indicated 280.33 891 0.250 1.329

Measured & Indicated 1,138.59 966 1.099 5.852

Inferred 187.28 820 0.154 0.817

1.The effective date of the Mineral Resource Estimate is April 29, 2024. The QP for the estimate is Ms. Terre Lane, MMSA, an employee of GRE and independent of Century.

2.The Mineral Resources are constrained by a pit shell with a 200 ppm Li cut-off and density of 1.505 g/cm3. The cut-off grade considers an operating cost of$20/t mill feed, process recovery

of 78% and a long-term lithium carbonate price of $24,000/t.

3.The Mineral Resource estimate was prepared in accordance with 2014 CIM Definition Standards and the 2019 CIM Best Practice Guidelines.

4.Mineral Resource figures have been rounded.

5.One tonne of lithium = 5.323 tonnes lithium carbonate.

6.Mineral Resources are inclusive of Mineral Reserves.

Mineral Resources are constrained by a pit shell using a 200 ppm lithium cut-off grade and assume a bulk

density of approximately 1.5 tonnes per cubic meter (“t/m³”). Mineral Resources are inclusive of Mineral

Reserves. Higher recoveries demonstrated through pilot-scale testing were determined to not materially

affect the selected cut-off grade or the reported Mineral Resource tonnage or grade.

Mineral Reserve Estimate (Unchanged from 2024 Study)

The Mineral Reserve estimate also has an effective date of April 29, 2024, and remains unchanged.

Proven and Probable Mineral Reserves:

• 287.65 million tonnes at an average grade of 1,149 ppm lithium, containing 1.759 million tonnes

LCE

Mineral Reserves are reported at a 900 ppm lithium cut-off grade, which is approximately 4.5 times the

calculated break-even cut-off grade, and support a mine life exceeding 60 years, with a 40-year production

schedule used in the economic analysis.

Mineral Reserve Estimate

Domain Tonnes Above Cut-

off (millions) Li Grade (ppm) Li Contained

(million t) LCE (million t)

Proven 266.39 1,147 0.306 1.626

Probable 21.26 1,174 0.025 0.133

Proven & Probable 287.65 1,149 0.330 1.759

1.The effective date of the Mineral Reserve Estimate is April 29, 2024. The QP for the estimate is Ms. Terre Lane, MMSA, an employee of GRE and independent of Century.

2.The Mineral Reserve estimate was prepared in accordance with 2014 CIM Definition Standards and 2019 CIM Best Practice Guidelines.

3.Mineral Reserves are reported within the final pit design at a mining cut-off of 900 ppm. The mine operating cost is $5.44/t milled, processing cost of $40.9/t milled, G&A cost of $2.68/t

milled and a credit for the NaOH sales of $28.95/t milled. The NaOH sales credit is proportionally applied to all the operating costs to get appropriate costs for the cut-off grade calculation.

The cut-off grade considers a mine operating cost of $2.22/t, a process operating cost of $16.69/t milled, a G&A cost of $1.09/t milled, process recovery of 78% and a long-term lithium

carbonate price of $24,000/t.

4.The cut-off of 900 ppm is an elevated cut-off selected for the mine production schedule as the elevated cut-off is 4.5 times higher than the break-even cut-off grade.

5. Mineral Reserve figures have been rounded.

6.One tonne of lithium=5.323 tonnes lithium carbonate

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Mining Methods and Production Schedule

Mining will be conducted as a conventional open-pit operation using free-digging equipment, including

dozers, shovels, and haul trucks. No drilling or blasting is required.

The mine plan reflects a two-phase development strategy:

Phase 1: 7,500 tpd of mill feed

Phase 2: expansion to 15,000 tpd

A previously planned third expansion phase was eliminated. The production schedule prioritizes near-

surface, higher-grade mineralization in the early years, reducing waste movement and improving capital

efficiency.

Mineral Processing and Metallurgy

The processing flowsheet consists of:

• High-pH attrition scrubbing

• Hydrochloric acid leaching

• Neutralization and pressure filtration with dry-stack tailings

• Direct Lithium Extraction

• Lithium carbonate precipitation, drying, and packaging

• Reagent generation via on-site chlor-alkali plant

Metallurgical assumptions are supported by multi-year pilot plant operations through mid-2025. Leach

extraction of approximately 90% was demonstrated, resulting in an overall lithium recovery of

approximately 84%. A final lithium carbonate product grading >99.9% purity was consistently achieved.

Angel Island facilities include an integrated chlor-alkali plant producing hydrochloric acid and sodium

hydroxide. Surplus sodium hydroxide, as produced in excess in conjunction with the design production of

hydrochloric acid, is expected to be sold, contributing substantial additional revenue and thereby reducing

effective operating cost.

Capital Costs

A Class 3 capital cost estimate was prepared in accordance with AACE International guidelines. The updated

costs were developed using second-quarter 2025 data:

• Phase 1 (7,500 tpd) initial capital cost: estimated $997.4 million

• Phase 2 (15,000 tpd) expansion capital cost: estimated $660.2 million

Reductions to estimated capital costs relative to the 2024 Study are attributable to the elimination of a

third production phase, simplification of installed capacity, processing flowsheet optimization, and

updated vendor and construction cost inputs.

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Estimated Capital Costs

Initial

Phase 1 ($M)

Years 5+

Phase 2 ($M)

7,500 t/d Expansion

to 15,000 t/d

Mining & Support Equipment $23.5 $43.7

Site Preparation and Roads $3.0 $4.5

Processing Facilities $611.6 $341.1

Infrastructure $167.5 $135.2

Working Capital $14.0 $0.0

Owner's Costs $88.2 $62.8

EPCM $24.1 $19.5

Freight $4.7 $3.4

Cap Cost Contingency $60.7 $50.0

Total Capital Cost $997.4 $660.2

The chlor-alkali plant cost is $481.5 million in Phase 1 and $256.8 million in Phase 2, included in Processing

Facilities, and is vendor all-in turn-key constructed costs, inclusive of indirect costs, owners’ costs and

contingency.

Operating Costs

Average operating cost estimates were updated based on refined mine scheduling, updated reagent

consumption, and pilot-validated process parameters.

Average operating cost: approximately $22.45/t of mill feed, or $4,389/t of lithium carbonate.

Sodium hydroxide by-product revenue is equivalent to $5,393/t of lithium carbonate. If credited against

operating costs (which was not done in the average operating cost above), base operating costs would be

negative.

Estimated Operating Costs

Initial Phase 1

(7,500 tpd mill feed) $(000s)/y $/t feed $/t LCE % of Total

Mining $12,648 $5.25 $1,092 17%

Process $22,272 $9.24 $1,829 30%

Process (chlor-alkali plant) $33,254 $13.79 $2,730 45%

G&A $5,583 $2.32 $458 8%

Total Operating Cost $73,757 $30.59 $6,110 100%

Expansion Phase 2

(15,000 tpd mill feed) $(000s)/y $/t feed $/t LCE % of Total

Mining $20,056 $3.66 $685 17%

Process $29,981 $5.48 $1,065 25%

Process (chlor-alkali plant) $65,353 $11.94 $2,322 54%

G&A $5,993 $1.09 $213 5%

Total Operating Cost $121,383 $22.16 $4,285 100%

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Economic Analysis

The economic analysis of Angel Island was done using a discounted cash flow (“DCF”) model using only the

first 40 years of project life. Cash flows in the model were based on second-quarter 2025 U.S. dollars with

no escalation of costs or revenues. The DCF model uses a base-case discount rate of 8%. Financing costs

were excluded from the valuation.

The analysis includes generating gross sales from lithium carbonate and sodium hydroxide, before-tax cash

flow, which is gross sales minus operating costs, and after-tax cash flow, which is before-tax cash flow

minus taxes and capital costs. The NPV and IRR were calculated from the DCF.

The economic analysis uses a base-case lithium carbonate price of $24,000/t and an 8% discount rate.

• After-tax NPV: $4.01 billion

• After-tax IRR: 27.4%

• Profitability Index: 4.0

Sensitivity to Lithium Carbonate Price

Sensitivity analyses demonstrate Angel Island economics are most sensitive to lithium price and remain

robust across a wide range of cost and price assumptions.

Sensitivity Analysis

Lithium Carbonate Price $18,000/t $24,000/t $30,000/t

After-tax NPV $2.75 B $4.01 B $5.26 B

After-tax IRR 22.2% 27.4% 32.1%

Profitability Index 2.8 4.0 5.3

Environmental, Permitting, and Social Considerations

Baseline environmental studies are complete. Permitting is expected to proceed under the National

Environmental Policy Act (“NEPA”) through the US Bureau of Land Management. Angel Island is currently

in the permitting stage, with no material changes to the permitting pathway outlined in the 2024 Study.

Interpretation and Conclusions

The 2026 Feasibility Study concludes that the Angel Island project is technically and economically viable,

with improved capital efficiency, reduced execution risk, and robust long-term economics. The simplified

two-phase development plan, extensive metallurgical validation, and integrated chlor-alkali process

support Angel Island’s competitiveness as a domestic US. source of battery-grade lithium carbonate.

In addition, the integrated chlor-alkali process also provides environmental and operational advantages

relative to sulfuric acid-based systems, including on-site reagent production.