EV Battery Diagnostics by CS

ChatStick Co., Ltd.

About this app

EV Battery Diagnostics is a practical, fully offline service toolkit and technician handbook for automotive technicians, students, EV specialists, fleet teams, and serious learners who want a structured way to understand and service high-voltage battery systems.

The interactive tools, service records, quizzes, and guided diagnostics are the core of the app — and the complete EV Battery Diagnostics & Maintenance Handbook is included as a bonus reference. Everything works without an internet connection. No account, no ads, no subscriptions.

WHAT YOU CAN DO

• Diagnose with confidence — guided decision-tree flowcharts for reduced range, slow DC charging, insulation faults, and cell imbalance walk you to a likely cause and recommended action.
• Look up fault codes — a searchable DTC reference library with likely causes and links to the related handbook chapter.
• Run the numbers — eight technician calculators: State of Health, Cell Balance Analyzer, Range Estimator, Charging Time & Cost, HV Safety Timer, Degradation Projector, Insulation Resistance, and Pack Configuration. Metric or imperial.
• Keep service records — add vehicles (NMC, LFP, or solid-state), log sessions with mileage, SOH, capacity, and cell spread, watch the SOH-vs-mileage trend chart against a 70% threshold, and export a PDF service report.
• Work the procedure — a four-phase service checklist (safety & preparation, data collection, capacity & balance evaluation, service & disposition) that saves your progress.
• Prove your knowledge — per-chapter quizzes, a 20-question certification exam with a shareable completion certificate, missed-question review, a glossary, and quick-reference cards.
• Read the full handbook — twelve offline chapters with images, bookmarks, personal notes, adjustable text size, resume-where-you-left-off, and full-text search.
• Stay sharp — a home-screen widget rotates daily EV battery service tips, plus an optional daily learning reminder.

BUILT FOR THE BENCH

• 100% offline — all content ships inside the app.
• Light and dark themes, adjustable text size, metric/imperial units, and haptics.
• Phone and tablet layouts.
• Your data — progress, notes, vehicle records, quiz and exam history — stays on your device.

This app is a learning and workflow aid. It does not replace OEM service information, certified high-voltage training, shop safety rules, or vehicle-specific repair procedures. Always follow manufacturer documentation and applicable safety regulations before working on any high-voltage system.

© ChatStick Company Limited

What’s new

Version 1.0