--- title: "Qualification" canonical: "https://anchor.is/the-hysteresis/issue/13/qualification" publication: "The Hysteresis" publisher: "The Hysteresis" language: "en-US" guide: "https://anchor.is/the-hysteresis/llms.txt" permalink: "https://anchor.is/the-hysteresis/issue/13/qualification" issue: 13 section: "qualification" description: "Pack-level requirements, test conditions, and standards by application" authors: ["Ronan Adike"] published: 2026-09-07 updated: 2026-09-04 articles: 20 --- # The Hysteresis > The Hysteresis exists to give a small cross-functional team — strategy, investment, and procurement — a shared weekly instrument for reading the battery supply chain earlier than consensus. Success means the team consistently identifies inflection points in cell pricing, supplier health, and policy enforcement weeks or months before they surface in earnings calls, annual surveys, or trade press. The commercial mechanism is internal-first: the publication proves itself as a decision tool inside the organization, then extends to paid subscribers and a practitioner community as upside. Revenue follows utility — if the team makes better-timed procurement calls and competitive assessments because of what they read here, the publication earned its place. [Read on the website]() ## Issue 13 — Qualification Pack-level requirements, test conditions, and standards by application ### The Standards Map - [Compound Stressor Gaps in eVTOL Propulsion Battery Qualification]() — By [Ronan Adike]() · Published 2026-09-04 · Format: The Standards Map EASA MOC VTOL.2440 requires trigger method, SOC, internal-short position, and heating rate to be characterized as interacting variables — the strongest compound stressor mandate any regulator has published for propulsion batteries. The FAA has no public equivalent. This card maps four consequential stressor combinations the eVTOL mission presents against what each jurisdiction governs and what the DVP must define itself. All four are program-owned in at least one jurisdiction, and two — aging severity and mission-duty conditioning before initiation — are program-owned in both. ### Application Interaction Cards Qualification standards test stressors in isolation. Mission profiles impose them simultaneously. A pack that passes thermal abuse, vibration, and altitude tests sequentially has demonstrated tolerance to each condition independently, but the operating environment delivers two or more at once, often on cells already degraded by prior duty cycles. These cards map the gap between sequential test coverage and simultaneous operational exposure across eVTOL, UAS, humanoid robotics, and subsea applications. Each card identifies the individual stressors addressed by current standards, the stressor combination present in the actual mission profile, and whether any governing document requires that combination. Three gap classifications apply: coupling gap, where individual tests exist but the combination is unaddressed; coverage gap, where no test reaches the condition at all; program-owned, where no governing standard exists for the application and the full test definition falls to the development program. - **MOC-3 Mandates Aged Article, SOC, and Thermal Combined** — [Source]() — Published 2026-09-04 Tag: eVTOL Propagation EASA MOC-3 (SC-VTOL Issue 2) requires propagation testing on aged or environmentally stressed articles at specified SOC, stabilized at 55°C or max operating temperature. Strongest published combined-stressor requirement across all four applications reviewed. Aging method and degree remain applicant-defined through EASA coordination. - **Fast-Charge After High-Rate Discharge Has No Combined Test** — [Source]() — Published 2026-09-04 Tag: eVTOL Charging CAP 3203 documents elevated pack temperature following high-rate landing discharge. Fast-charge initiation at 30–40% SOC in this thermal state raises lithium plating and T1 approach risk. MOC-3 and DO-311A treat charging and thermal conditions as separate tests. The turnaround sequence conjunction is unaddressed. Coupling gap. - **Concurrent Vibration and Discharge Has No UAS Test** — [Source]() — Published 2026-09-04 Tag: UAS Vibration Multirotor drones sustain airframe vibration concurrent with variable-rate discharge throughout flight. IEC 62619 and ASTM F3005-22 test mechanical and electrical conditions separately. No reviewed UAS battery standard requires simultaneous vibration and electrical cycling. Coupling gap — program-defined test required. - **UN 38.3 Altitude Simulation Applies Zero Electrical Load** — [Source]() — Published 2026-09-04 Tag: UAS Altitude UN 38.3 T.1 simulates reduced pressure at zero electrical load for transport eligibility. Drones discharge at operational altitude under reduced ambient pressure simultaneously. No UAS battery standard requires altitude simulation with concurrent discharge. Transport test does not represent operational conjunction. Coupling gap. - **Fall Impact at Operational SOC Entirely Program-Defined** — [Source]() — Published 2026-09-04 Tag: Humanoid Impact No dedicated humanoid battery standard exists. IEC 62619 Cl. 7.2.3 covers drop without specifying SOC, orientation, monitoring duration, or human-proximity propagation acceptance criteria. The full conjunction — fall energy, charged state, thermal observation window, proximity consequence — must be defined at program level. Program-owned. - **Locomotion Duty History as Abuse Preconditioner Is Undefined** — [Source]() — Published 2026-09-04 Tag: Humanoid Aging Humanoid packs sustain continuous mechanical shock from locomotion simultaneous with electrochemical cycling at 140–420 W sustained load. No borrowed standard mandates a humanoid-representative duty-cycle history before propagation or abuse testing. T1 and T2 reduction from realistic operational aging remains untested when fresh articles are used. Program-owned. - **Pressure Plus Electrical Duty Has No Combined Protocol** — [Source]() — Published 2026-09-04 Tag: UUV Pressure ABS Rules §10/11.5.6 require pre-service pressure testing to design depth and separate BMS functional testing. UUVs discharge continuously under hydrostatic pressure throughout the mission. No ABS clause or commercial standard specifies mission-representative electrical load during the design-depth pressure condition. Coupling gap. - **Thermal Runaway Propagation at Depth Has No Test** — [Source]() — Published 2026-09-04 Tag: UUV Propagation NAVSEA S9310 Rev. 3 specifies propagation acceptance at approximately atmospheric conditions. Venting behavior, gas expansion, and containment response depend on ambient pressure. No commercial class rule or ISO document establishes an induced-fault propagation test at design-depth hydrostatic pressure. Coverage gap — the condition itself is unaddressed. ### Non-Governing Technical Evidence - **Quantifying the key parameters of thermal runaway in aviation lithium-ion battery modules under different triggering methods** — [Source]() — Published 2026-09-04 Compared local and overall heating triggers on a 12-cell, 300 Ah pouch aviation module. Local heating yielded higher explosion hazard (TNT equivalent 307 g vs. 235 g); overall heating produced higher peak temperature (1358 C vs. 965 C) and faster propagation. Each method envelopes a different failure mode. DVP implication? Trigger method determines which failure mode the test envelopes — the DVP row must record the hazard signature being maximized, not just the method used. Source tier? Journal of Energy Storage, May 2026. Tier 3 input — informs trigger selection for airworthiness verification but does not prescribe it. - **A novel pressure compensated structure of lithium-ion battery pack for deep-sea autonomous underwater vehicle** — [Source]() — Published 2026-09-04 Analyzed pressure-tolerant vs. pressure-compensated AUV pack architectures across 300–6000 m (3–60 MPa). A piston-compensated, oil-immersed 8s9p NCM design saved at least 18.3% structural weight at 60 MPa while reducing peak battery temperature — both effects produced by the same dimethyl silicone oil medium. DVP implication? The oil medium couples pressure management and thermal management in one physical element — testing them independently leaves joint behavior at operating depth uncharacterized. Standards gap? ABS section 10/11.5.6 requires pressure testing but specifies no margin, ramp rate, hold time, or SOC condition. - **The effects of different trigger methods on thermal runaway propagation in a 6.6 kWh lithium-ion pouch-cell battery module** — [Source]() — Published 2026-09-04 Applied four trigger methods (electrical pad heating, local flame, 1–2C overcharge, 50 kW burner) to a 6.6 kWh NMC pouch-cell module. One method caused full-module propagation; another produced none. Trigger selection determined whether propagation occurred at all, not just its severity. What separated the outcomes? Four triggers on the same module yielded qualitatively different results — full propagation under one method, no propagation under another. Why cite alongside the aviation study? Corroborates on a different module that trigger-method variation can determine whether propagation occurs, not merely how fast. - **Review of pressure compensated immersion battery systems for deep-sea power applications** — [Source]() — Published 2026-09-04 Surveys pressure-compensated immersion battery architectures for deep-sea applications, covering oil-immersed thin-film and piston-compensator designs across depth ranges. Architecture selection between pressure-tolerant and pressure-compensated designs is depth- and mission-dependent; no governing class rule prescribes the choice. Architecture decision? Selection between pressure-tolerant and pressure-compensated designs varies with depth profile and mission — a DVP must document the rationale explicitly. Source tier? Applied Energy, June 2026. Tier 3 review contextualizing subsea pack architecture decisions where settled standards guidance does not yet exist. ### Institutional Coupling Gap - [SAIL III Finalized Design Assurance Without an Energy-Storage MoC]() — By [Ronan Adike]() · Published 2026-09-04 EASA's SAIL III design-assurance route is institutionally settled. Final MoCs for OSO #2, #3, #5, #6, #8, #18, #19/#20, and #24 — covering design assurance, C2 link, envelope protection, environmental conditions, and operational documentation — closed consultation in September 2025 and are published with declaration forms. An engineer filling DVP rows for these process-layer requirements has a regulatory template to cite. ### Source Access - **TR Trigger Method Alters Propagation Path and Explosion Severity in Aviation Battery Modules** — [Source]() — Published 2026-09-04 Local heating yielded ~2x power density vs. overall heating but lower peak temperatures. Trigger selection is a DVP variable. - **MIL-STD-810H Method 520.5: Combined-Environment Testing Complements Single-Stressor Coverage, Does Not Replace It** — [Source]() — Published 2026-09-04 Method 520.5 couples temperature, humidity, vibration, and altitude. DVPs need both combined and individual test lines. - **Simultaneous Temperature-Vibration Loading Exposes Failure Modes Sequential Battery Testing Misses** — [Source]() — Published 2026-09-04 Thermal expansion mismatch under concurrent vibration accelerates fatigue beyond what stacked single-stressor sequences predict. - **Cross-Standard Harmonization Review Catalogs Persistent Variability in LIB Safety Test Protocols** — [Source]() — Published 2026-09-04 Heating rates, TR-initiation criteria, and chemical abuse coverage still diverge across IEC, SAE, and UL frameworks as of 2026. - **EASA SC-VTOL MOC-5: Response-to-Comments Still Pending After October 2025 Consultation Close** — [Source]() — Published 2026-09-04 No final MOC-5 publication through September 2026. eVTOL battery safety MOCs remain in draft for DVP purposes. - **TRP Containment Requirements Diverge Sharply Between Manned eVTOL and UAV Safety Targets** — [Source]() — Published 2026-09-04 Without active TRP mitigation, conservative safety targets are met for UAVs but not manned eVTOL configurations. ## Other sections in Issue 13 - [Signal]() - [China]() - [Korea]() - [The Log]() - [Defense]() ## More - [Publication guide]() - [Issue archive]()