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Flux XII

Flux XII

Private
Madison, WisconsinEnergy & Sustainabilityhttps://www.flux12.com/

Last Round

Seed

Nov 4, 2025

Total Funding Raised

$5.05M

Momentum

Top 50%

of companies Caplight tracks

Company Overview

Flux XII is an energy storage company that develops advanced materials and modules for aqueous flow batteries to transform intermittent renewable power into reliable grid capacity.

Sector

Energy & Sustainability

Verticals

Energy Storage, Advanced Materials, Sustainable Materials

Business Model

B2B

Customer Profile

Hardware Sales, Government Contracts, Services & Consulting

AI Layer

Non-AI

Keywords

aqueous flow batterylong-duration energy storageLDESgrid energy storageflow batterybattery energy storage systemsBESSorganic redox materialsadvanced materialsutility-scale storageelectrolytesion-exchange membranesrenewable energy storagemicrogridgrid stability

Historical Pricing

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Caplight Momentum Score

Proprietary index based on bid/ask volume and sentiment.

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Flux XII Comparables

Compare Flux XII with similar companies based on industry and business-model similarity.

Flux XII comparables — related companies by embedding similarity
CompanySimilarityMarket Cap
Quino Energy
94%
CarbeniumTec
89%
Otoro Energy
89%

Flux XII Funding Rounds

Historical fundraising activity

Data table
RoundDateAmount RaisedValuationInvestorsSources
SeedNov 4, 2025
AcceleratorApr 29, 2025
Pre SeedSep 1, 2023

Key People

Founding team and executive leadership

Patrick Sullivan

CEO and Co-founder

Founding Team

Flux XII Investors

Notable investors and investment history

Flux XII investors
InvestorRounds
gener8torAccelerator, Seed
Gigascale CapitalPre Seed, Seed
The Grantham Foundation for the Protection of the EnvironmentSeed
Collaborative FundPre Seed, Seed
Safar PartnersPre Seed, Seed
Desai VenturesSeed
ActivatePre Seed, Seed

Market signals

Structured signals derived from secondary market and firmographic data.

  • Jul 25, 2026

    Monthly visitors increased 30% MoM, reaching 2.9K.

  • Jan 8, 2026

    Monthly visitors increased 156% MoM, from 326 to 835.

Flux XII Filings

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Flux XII filings preview — column headings only; records require access
TypeDateAmount OfferedAmount SoldFilingPagesDownload

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Frequently Asked Questions

Common questions about Flux XII's valuation, stock price, and market status.

Is Flux XII a public or private company?

Flux XII is a private company.

What is the current stock price of Flux XII?

Flux XII is a private company with no public stock price. No recent secondary market data is available.

How much is Flux XII worth (valuation)?

Valuation information for Flux XII is not publicly available.

Can I buy Flux XII stock?

Flux XII shares may be available on secondary markets subject to transfer restrictions. Caplight facilitates secondary market transactions for accredited investors. Visit https://www.caplight.com to learn more.

When was Flux XII's last funding round?

Flux XII's most recent funding round was Seed on November 4, 2025.

Who are the main investors in Flux XII?

Key investors in Flux XII include The Grantham Foundation for the Protection of the Environment.

Will Flux XII IPO soon?

No public IPO plans have been announced for Flux XII.

How can I track Flux XII secondary market activity?

Caplight tracks bids, offers, and trades for private companies. Visit https://www.caplight.com to monitor Flux XII's secondary market activity and sign up for updates.

Firmographic Details

HeadquartersMadison, Wisconsin
Employee Range5
Year Founded2022
Last FundingNov 4, 2025

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