{"schema_version":1,"experiment_id":"eoa_inverse_innovation_exp09_archetype_breadth150_20260804","cell_id":"rate_limiting__chemistry_materials","arm":"BREADTH_PROBE_ONE_SHOT","candidate_id":"rate_limiting__chemistry_materials__P1","proposal_index":1,"version":0,"title":"Token-Bucket Powder Admission for Conductive-Carbon Slurry Mixing","problem":"During lithium-ion cathode slurry preparation, conductive-carbon powder can enter the liquid faster than the mixer can wet and disperse it. Although the total powder charge is correct, transient overfeeding can create floating rafts, dry pockets, torque excursions, and agglomerates that persist through the prescribed mixing cycle.","actors":["Slurry-mixing operator","Materials process engineer","Quality-control analyst","Powder-feeder controller","Laboratory manager and environmental-health-and-safety reviewer"],"observable_state":"The feeder or manual addition produces short mass-flow spikes; mixer torque or power rises abruptly; visible unwetted powder persists at the surface or vessel wall; and subsequent samples show coarse particles, unstable rheology, or coating defects. Powder mass admitted per rolling time window is not presently measured or enforced.","consequence":"A correct formulation can leave mixing with nonuniform conductive-carbon dispersion, prompting additional mixing, rework, or rejection and potentially producing nonuniform electrode coatings.","affected_objective":"Produce a compositionally correct cathode slurry with reproducible dispersion and coatable rheology while maintaining safe powder handling and reasonable batch duration.","intervention":"Place the conductive-carbon feeder behind recipe-specific metered admission. Count admitted powder mass against a token bucket: tokens refill at a validated grams-per-minute rate, the bucket permits a small defined burst, and the feeder pauses when tokens are exhausted. Powder denied immediate admission remains sealed in the hopper and is released only as allowance refills, without a reset-driven catch-up burst. Mixer temperature and torque retain independent safety-stop thresholds; they do not grant extra tokens during the initial test.","structural_mapping":[{"archetype_element":"Flow","domain_realization":"Grams of conductive-carbon powder crossing from the sealed feeder into the slurry mixer."},{"archetype_element":"Finite shared capacity","domain_realization":"The liquid surface, wetting kinetics, and available dispersive work can incorporate only a bounded powder flux without accumulating dry material."},{"archetype_element":"Measurement window","domain_realization":"Powder mass is totaled over rolling short and long windows rather than controlled only by final recipe mass."},{"archetype_element":"Admission-control boundary","domain_realization":"The feeder gate or screw-drive command determines whether powder may enter the vessel at that moment."},{"archetype_element":"Rate envelope","domain_realization":"A recipe-specific sustained feed rate plus a limited burst allowance bounds accepted powder flux."},{"archetype_element":"Predictable excess handling","domain_realization":"Temporarily unadmitted powder stays in the sealed hopper; the controller reports remaining allowance and estimated completion time."},{"archetype_element":"Critical-capacity preservation","domain_realization":"The cap reserves mixer wetting and dispersion capacity instead of allowing a powder surge to consume it all at once."},{"archetype_element":"Observability and auditability","domain_realization":"Feeder mass flow, token balance, pauses, torque, temperature, visible incorporation time, and sampled slurry properties are time-aligned in a batch record."}],"mechanism_mapping":[{"mechanism_slug":"token_bucket","role":"Allows a small legitimate addition burst while bounding sustained grams-per-minute admission across the complete powder-addition period.","counterfactual_removal":"Without the token balance, the feeder can reproduce the same high-rate spikes even if an operator is given an average-rate target."},{"mechanism_slug":"metered_admission","role":"Measures powder crossing the vessel boundary and pauses entry before excess material is committed to the mixer.","counterfactual_removal":"If powder is measured only after the full charge, the system controls total quantity but cannot prevent temporal overload."}],"causal_chain":["Conductive-carbon powder arrives at a rate that can exceed the mixer's current wetting and dispersion capacity.","Excess powder accumulates as dry rafts, wall deposits, or locally concentrated agglomerates.","Those accumulations require dispersive work beyond the prescribed cycle and may persist into the finished slurry.","Metering makes instantaneous and rolling powder flux observable.","The token-bucket rule bounds admitted flux while retaining a small burst allowance.","When allowance is exhausted, powder remains upstream in the sealed hopper rather than becoming an in-vessel backlog.","Keeping admitted powder within the tested incorporation envelope is expected to reduce overload episodes while preserving the specified total formulation."],"baseline":"The recipe specifies total conductive-carbon mass and a target mixing duration, but an operator pours the powder or runs the feeder using visual judgment. Instantaneous addition rate is neither logged nor enforced. The full charge is then mixed for a fixed period, with longer mixing or rework considered after torque, visual, rheology, or fineness problems appear.","nearest_rivals":["A fixed low feeder speed, which constrains equipment command but does not meter actual mass flow or provide an explicit burst budget.","Increasing mixer speed or mixing duration, which adds dispersive work after powder has already entered and may change temperature or slurry structure.","Premixing or diluting the powder, which changes the material-handling route and formulation state rather than governing admission rate.","An emergency torque-triggered feeder shutdown, which reacts to an observed overload condition rather than maintaining a standing rate envelope.","A larger mixer or higher-power disperser, which expands capacity rather than rationing use of existing capacity."],"remaining_contrastive_claim":"The candidate's distinctive claim is limited to causal placement: controlling powder mass before it crosses into the vessel, over explicit rolling windows with a bounded burst allowance, can prevent transient incorporation overloads that total-charge control and post-admission mixing adjustments cannot prevent. It does not claim that feed rate is the dominant cause of all dispersion defects or that rate limiting substitutes for adequate mixing capacity.","authority_safety":{"decision_authority":"The laboratory manager retains authorization for non-production trials, with environmental-health-and-safety concurrence for any change to combustible-dust handling; production deployment remains under the site's formal process-change authority.","authorized_first_step":"The process engineer may program an advisory token schedule and conduct two non-production benchtop batches under the existing approved formulation and containment procedure: one using the current addition schedule and one using metered admission.","excluded_actions":["Changing formulation ratios, powder grade, solvent, or binder chemistry","Bypassing dust extraction, grounding, guards, temperature limits, torque limits, or emergency stops","Applying autonomous control to production equipment","Increasing feeder or mixer operation beyond existing approved limits","Allowing paused powder to accumulate outside the sealed hopper","Treating the rate limiter as a replacement for combustible-dust or chemical-exposure controls"],"halt_rollback":"Stop powder admission immediately if containment, dust-control, temperature, torque, or equipment alarms cross existing limits. Keep extraction and the mixer in the state required by the approved shutdown procedure, secure the hopper, document the partial charge, and disposition it under the existing off-spec procedure. Remove the advisory controller and return the benchtop setup to the approved manual-feeding configuration before further work."},"negative_tests":{"strongest_counterevidence":"Agglomerates are already present in the incoming powder, or arise during later solvent loss, storage, or coating, while time-aligned records show no relationship between powder-flux spikes, incorporation delay, torque behavior, and final dispersion measures.","problem_falsifier":"Under fixed formulation, powder lot, fill level, temperature, and mixing-energy conditions, batches spanning materially different addition-rate profiles show comparable incorporation time, torque response, fineness, rheology, and coating appearance, with defects instead tracking another variable.","intervention_falsifier":"The metered batch stays within its programmed admission envelope but does not reduce visible powder accumulation or torque excursions and does not improve the selected dispersion indicators, or it creates unacceptable temperature, exposure-duration, settling, or batch-time consequences.","risks":["A cap set too low can lengthen powder-handling exposure and alter the sequence of wetting or binder dissolution.","A cap set too high will preserve the original overload.","Feeder calibration error can make commanded tokens differ from actual admitted mass.","Pauses can create feeder compaction or pulsed restart flow.","A reset or manual override can release a catch-up burst.","One recipe's safe envelope may be unsafe or unnecessarily restrictive for another powder, solids fraction, fill level, or mixer geometry.","Rate control can mask inadequate mixer capacity or defective incoming powder.","Longer addition time can change slurry temperature, solvent loss, or process chronology even when total mixing energy is held nominally constant."]},"next_evidence_step":"Run the authorized two-batch, non-production benchtop comparison using one powder lot and fixed formulation, fill level, temperature limits, mixer program, and total powder mass. Log powder mass flow, token balance, torque, power, temperature, pause duration, and time until no dry powder is visible; then apply the laboratory's existing fineness, rheology, and small coating-inspection methods to blinded samples. Treat the candidate as unsupported if the limiter fails to bound measured flux, if safety or exposure limits are approached, or if the prespecified problem and intervention falsifiers are observed. This step authorizes no production change and no inference beyond the tested recipe and apparatus.","prior_art_status":"UNSEARCHED","diversity_from_prior_proposals":"Not assessed against other proposals because runtime isolation forbids inspecting them; this candidate is derived solely from the supplied rate-limiting archetype and chemistry-and-materials domain card.","revision_record":{"parent_version":null,"progress_targets_addressed":["Initial one-shot candidate generation from the supplied archetype and domain record"],"conceptual_changes":[],"operational_changes":[],"evidence_changes":[],"claim_changes":[]}}