QualificationExact sourced interface · in-enclosure thermal behaviour unqualified
ArticleLP503562 · lithium-polymer
ProtectionIntegrated protection circuit fitted
Capacity1200 mAh at 3.7 V = 4.44 Wh
Voltage window3 V cutoff → 3.7 V nominal → 4.2 V full
Body34 × 62 × 5 mm
Swell allowance0.5 mm of pocket depth beyond the cell, reserved by the enclosure
Terminationjst-ph · 50 mm leads
Geometry authority: declared-envelope
Datum: Pouch back face at z = 0; leads exit +Y; corner at origin.
Vendor-listed envelope, mass, capacity, protection behaviour and chemistry limits for Adafruit 258. There is no manufacturer drawing or datasheet behind it: no dimensional tolerance, no cycle-life curve, no thermistor. The solid is the stated envelope as a plain slab; foil seal skirt, tab exit and protection-circuit bulge are unmodelled. swellAllowanceMm is a flat 10 % of thickness stated as a catalog rule, not a manufacturer ageing figure. Adafruit does not publish a cable length for this SKU; 50 mm is a conservative routing FLOOR, not a measured figure — the delivered cable is longer. Capacity, internal resistance, real swell over life, self-discharge and thermal behaviour remain unmeasured.