T1 18650 rectangular surrogate grammar#

Tier-1 rectangular battery grammar benchmark with fixed topology representation and switchable analytic, explicit-circuit, or hybrid-thermal scoring.

See Grammar Problem Catalog for the grammar family index.

Quick Facts#

Field

Value

Problem ID

battery_18650_t1_rectangular_surrogate_grammar

Problem Family

grammar

Implementation

design_research_problems.problems.grammar._battery_tiers:Battery18650T1RectangularSurrogateGrammarProblem

Capabilities

discrete-actions, external-adapter, optional-evaluator, serializable-state, statement-markdown

Study Suitability

none

Tags

grammar, battery, tiered, tier-1, rectangular, surrogate

Taxonomy#

Formulation

discrete_grammar

Convexity

not_applicable

Design Variable Type

discrete

Is Dynamic

no

Orientation

engineering_practical

Feasibility Ratio Hint

0.1

Objective Mode

multi

Constraint Nature

hard

Bounds Summary

rectangular SxP topology with explicit grid coordinates

Tags

grammar, battery, tiered, tier-1, rectangular, surrogate

Benchmark Contract#

Benchmark Question

How well do grammar methods navigate the lowest-freedom rectangular pack design space under hard requirements?

Physically Modeled

Canonical rectangular SxP pack edits; Shared pack metrics and a steady-state thermal proxy; Backend consistency checks through the shared battery cell-model path

Deliberate Surrogates

Topology is constrained to the rectangular family; Electrical performance is summarized by analytic pack equations

Representation Mode

rectangular

Default Evaluation Mode

analytic_surrogate

Supported Evaluation Modes

analytic_surrogate, explicit_circuit, hybrid_thermal

Validation Scope

Analytically checked surrogate consistency; Canonical-pack backend sanity checks

Solver Role

grammar benchmark; no packaged optimizer

Statement#

Tier 1 exposes the lowest battery-design freedom. Designers can reposition cells on the canonical grid and add or remove complete series stages or parallel branches while preserving a full rectangular SxP topology.

This is the first rung of the battery ladder and serves as the constrained baseline before richer pose, topology, and thermal decisions are unlocked.

Evaluation uses the same shared battery metric contract as optimization tiers. Core electrical relations:

  • V_pack ~= S * V_cell

  • C_pack ~= P * C_cell

  • I_limit ~= P * C_cell * C_rate_max

Thermal relation:

  • I_cell = I_load / P

  • Q_dot = N_cells * I_cell^2 * R_int

  • T_max = T_ambient + Q_dot / (G_passive + hA)

Problem Shape#

Field

Value

State Type

SeriesParallelBatteryState

Initial Transition Count

21

Initial Rule Names

add_parallel_branch, add_series_stage, move_cell

Manifest Parameters#

Key

Value

evaluation_mode

analytic_surrogate

max_depth_mm

500

max_height_mm

250

max_width_mm

500

minimum_capacity_ah

10

minimum_current_a

60

target_voltage_v

14.8

voltage_tolerance_v

0.1

Initial Transition Summary#

Rule Name

Transition Count

add_parallel_branch

7

add_series_stage

7

move_cell

7

Library Interface#

  • initial_state()

  • enumerate_transitions(state)

  • enumerate_next_states(state)

  • evaluate(state)