Two Stores, One Power Pack: Battery–Supercapacitor Hybrid Storage and the Patented Hybrid Power Pack. A Consolidated Scientific Monograph on the Physics, Architecture, Control, Battery Management, Sizing, Safety, Standards and Evidence

A single, consolidated monograph on pairing a battery with a supercapacitor (electric double-layer capacitor) and on the patented Hybrid Power Pack architecture (US 10,523,019 B2 and family). It brings together the author's earlier preprints on this subject and extends them with new chapters. It covers the physics of the two stores and their time scales; how a load current divides between them; the relation 1 − 1/FF² for battery-heat reduction, with partial buffering, capacitor sizing and the net-energy boundary; the claimed architecture and one realisation of its switches; controller operating states and energy management; battery management (balancing, protection, integration); five charging inputs; applications ranked by physics, with published evidence by sector; minimum-weight capacitor sizing across twelve applications, including the battery-electric car and photovoltaic smoothing; cold operation and regenerative braking; self-discharge, heat and life; safety and standards; the test record of HPP hardware; and a list of benefits and of every quantitative claim with its justification. Every number is labelled as sourced, computed or assumed, and design descriptions beyond the claims are labelled as design realisations. Not peer reviewed. AI-assisted tools were used in drafting, calculation, figure generation and reference checking; the author reviewed all content and takes full responsibility for it.