Provenance Record

Well-structured News piece (685 words, within the 400-1200 News range). Clean Overview / What We Know / What We Don't Know / Analysis sections. Technical depth is appropriate and the speculative boundary is handled honestly, with an explicit 'What We Don't Know' section calling out the undisclosed investment size, absent commercial-manufacturing timeline, missing production volumes, and unstated cell energy density.

All 3 source snapshots read from disk and verified. source-0.html.gz (PR Newswire, official Peak Energy/GM joint release, status 200): confirms verbatim 'GM will develop the sodium-ion cell in its Michigan battery labs and retain exclusive manufacturing rights, while Peak will incorporate the cell into its proprietary energy storage systems'; 'Backed by a strategic investment from GM Ventures in Peak Energy' with NO dollar figure stated; passively cooled platform, 20% cost reduction, >99% uptime, up to 2 TWh/year waste reduction; both quotes verbatim (Kurt Kelty, VP of Battery and Sustainability at GM; Landon Mossburg, CEO and Co-Founder of Peak Energy), release dated Jun 9, 2026. source-1.html.gz (Energy-Storage.News, status 200): confirms exclusive manufacturing rights to the Na-ion cell, prototype at Warren, Michigan / Wallace Battery Cell Innovation Center before end of 2026, 'first production of prototypes this year', 720MWh Jupiter Power agreement extending to 4GWh, 1.5GWh Energy Vault agreement, RWE 3.1MWh pilot at an R&D lab in Wisconsin, GM Ventures strategic investment. source-2.html.gz (CleanTechnica, status 200): confirms the 'Empower' event framing, Warren/Wallace R&D center, 'Sodium is also one of the most abundant elements on Earth' (verbatim), Ultium Cells JV with LG Energy Solution producing LFP, Redwood Materials ~10,000 second-life packs into energy infrastructure incl. Crusoe's AI data center in Sparks, Nevada.

Every claim, number, name, date, and quote traces to a cited snapshot. Quotes are verbatim and correctly attributed by speaker and title. CRITICAL CHECKS PASSED: (1) the GM Ventures investment amount is correctly left UNDISCLOSED — no fabricated figure appears in the article, matching the sources which state no amount; the body explicitly notes 'no dollar figure was disclosed' and dedicates a 'What We Don't Know' line to it. (2) The dropped '~1,000x more plentiful than lithium' figure (which would have rested on the single non-allowlisted source Electric Cars Report) is genuinely ABSENT from the article body — confirmed '1,000', '1000', 'plentiful', and 'Electric Cars Report' do not appear; the abundance claim is instead the milder, source-backed 'Sodium is one of the most abundant elements on Earth' attributed to CleanTechnica, which states exactly that. No hallucinations detected.

Clean APPROVE. All integrity checks pass, all three sources read and verified, every quote verbatim and correctly attributed, every specific sourced, the headline/summary/lead are each backed, no orphan body URLs, and the two judgment-call risk areas (undisclosed investment amount, dropped non-allowlisted abundance figure) are both handled correctly. Ready for publication.