Donut Lab’s all-solid-state battery delivers 400 Wh/kg of energy density

Original Article ↗ Hacker News Discussion ↗

Overall sentiment: “Huge if true” but strong skepticism

  • Many see the specs as effectively “magic battery”: ~400 Wh/kg, lithium‑free, geopolitically abundant materials, 100k cycles, 5‑minute full charge, minimal degradation, wide temperature range, safer and cheaper than Li‑ion.
  • That combination is viewed as so ideal that commenters assume there must be a catch: cost, manufacturability, cycle life, or outright exaggeration.

Credibility of Donut / Verge / Nordic Nano

  • Skeptical points:
    • Donut isn’t a known battery player; sparse technical detail, no patents or chemistry discussion, no named independent lab reports.
    • Company web presence (no physical address, “drag & drop OS” EV platform) reads as hype to some.
    • Multiple tightly linked companies (Donut, Verge, others) and Finland factory photos are seen by some as grant‑chasing or branding, not proof.
    • Solid‑state has a history of overpromising; prior bus deployments had delamination and fires.
  • Supporting points:
    • The battery is claimed to be in a real Verge motorcycle model, viewable/test‑ridable at physical stores and at CES; bike platform with conventional batteries already exists.
    • Nordic Nano connection and Finnish university spin‑out background lend some plausibility.
    • Donut already builds axial‑flux motors used by OEMs; this isn’t a pure “from nowhere” shell.

Technical questions and inconsistencies

  • Conflicting fast‑charge claims: Donut page says 0–100% in 5 minutes; Verge video claims ~50% in 10 minutes. Explanations floated: different pack sizes, cooling and packaging limits, or simple marketing sloppiness.
  • 400 Wh/kg and 5‑minute full charge imply ~megawatt‑class charging for car‑sized packs; commenters note cable cooling, voltage, and infrastructure constraints.
  • Range claims (e.g., 600 km city, dramatic drop on highway) rely on soft “reasonable approximation” language; EU‑standard tests are “TBC.”
  • Structural / “clay‑like” geometries are advertised, but others warn about thermal management and mechanical strain; structural batteries are known to be tricky.

Market, applications, and implications

  • Motorcycle debut is seen as a niche, high‑price first application (similar to Tesla’s early strategy) and a function of smaller volume and simpler bizdev than cars.
  • If validated at scale, commenters expect big impact on EV adoption, drones/VTOL, and military systems; also geopolitical implications of a non‑Chinese, lithium‑free chemistry.
  • Consensus: wait for third‑party lab tests, teardown data, and actual shipping units before believing extraordinary claims.