Lesson 1Battery repair process workflow: isolation, safe disassembly, cell verification, balancing, reassembly, and test cycleFollow a safe step-by-step battery repair flow. You will do isolation, open packs safely, check welds and covers, change cells, balance again, seal up, and test after repair before giving back scooters.
Isolation, PPE, and workbench preparationOpening packs without causing new damageCell replacement, welding, and insulationFinal balancing, sealing, and test ridesLesson 2Cell-level diagnostics: IR measurement, capacity estimation using simple timed load test, and spotting cell imbalancesGo deep into cell testing ways. You will measure inside resistance, guess capacity with time load tests, find uneven cell groups, and choose which cells to save or throw away for safety or cost.
Using ESR meters and four-wire techniquesTimed discharge tests for capacity estimatesFinding weak cells within parallel groupsCriteria for rejecting marginal cellsLesson 3BMS and firmware checks: extracting BMS logs/telemetry where possible, common BMS failure symptoms, and firmware reset/firmware update considerationsLearn to get and read BMS data if you can. You will check error logs, ride counts, heat history, firmware types, and know when to reset or update safely or change hardware.
Connecting to BMS apps, tools, or adaptersReading fault codes, flags, and event logsEvaluating cycle count and SOH indicatorsFirmware reset and update risk assessmentLesson 4Li-ion battery fundamentals: cell chemistry, nominal voltages, capacity (Ah), internal resistance, and state-of-charge estimationKnow Li-ion cell build, common types, and how voltage, capacity, resistance link. Learn how these change range, power, age, and how to guess charge level in workshop.
Common scooter chemistries: NMC, LFP, NCANominal, max, and cutoff voltage per cellCapacity (Ah) vs. energy (Wh) vs. C-rateInternal resistance and its measurement basicsLesson 5When to replace pack vs. repair cells: economic, safety, and longevity criteria; pros and cons of cell replacement vs. full pack replacementLearn to pick full pack change or cell fix. Compare money, safety space, life length, work time, risks so you suggest good choices for rider and your shop.
Cost comparison: parts, labor, and shop overheadRisk assessment: fire, recalls, and liabilityEstimating remaining useful life of old packsWhen to refuse repair and recommend new packLesson 6Interpreting symptoms: sudden shutdown at 40–50% and reduced range — common failure modes (capacity loss, increased internal resistance, BMS cutoff, cell group failure)Match real problems to battery faults. You will check sudden stops, less range, weak speed, bad gauge to tell capacity drop, high resistance, BMS stop, or cell group fail.
Patterns of range loss and voltage sagSudden cutoff at mid SOC and BMS triggersDiagnosing weak cell groups in series stringsDifferentiating pack vs. controller issuesLesson 7Battery management system (BMS) role: balancing, over/under-voltage protection, current limiting, and telemetry interfacesSee how BMS guards pack and rider. You will study balance ways, high low voltage cuts, current limits, heat sense, and how data goes to controllers or tools.
Passive vs. active cell balancing methodsOver/under-voltage and current protectionsTemperature sensing and thermal deratingBMS data lines: CAN, UART, and proprietaryLesson 8Preliminary non-invasive checks: open-circuit voltage, resting voltage distribution, and pack voltage vs. expected valuesDo quick no-open tests before pack work. You will measure open voltage, match specs, check rest voltage shift, and pick deep check or quick change.
Measuring pack open-circuit voltage safelyComparing measured voltage to nameplate dataMonitoring resting voltage over several hoursRed flags that justify deeper investigationLesson 9Under-load and charging checks: voltage sag under load, charge acceptance, charger output verification, and charge port/connector inspectionLearn safe battery tests on ride load and charge. You will measure voltage drop, check charger power, charge take, and look at ports for heat, rust, damage.
Simulating real-world load with test equipmentMeasuring and interpreting voltage sagVerifying charger voltage and current outputInspecting charge ports, pins, and wiringLesson 10Battery safety and customer communication: explaining thermal runaway risk, storage/charging guidance, safe transport, and warranty/legal disclaimersBuild safe habits and clear talk with customers. You will explain heat runaway danger, store charge rules, carry safe, and note waivers, limits on warranty.
Recognizing and handling high-risk batteriesSafe charging, storage, and transport guidanceCustomer education scripts and checklistsDocumenting waivers and repair limitations
