Redox reactions, electrode potential, and chemical energy explain why a battery can push current through a circuit. You will connect chemistry to measurable voltage.

Follow the path from early batteries to rechargeable lithium-ion cells and the choices that made modern phones, laptops, EVs, and grid storage possible. The chapter shows how safety problems, materials breakthroughs, and manufacturing scale shaped today’s designs.

Break down a cell into cathode, anode, separator, electrolyte, current collectors, tabs, casing, and safety vents. You will know what each part does and what can go wrong when it fails.

Lithium-ion cells usually store energy by sliding lithium into host materials rather than plating metal. This chapter explains intercalation, staging, diffusion, and why the host structure matters.

Use capacity, nominal voltage, energy, C-rate, cycle life, impedance, temperature limits, and cutoff voltage correctly. You will be able to compare datasheets without being fooled by headline numbers.

Cathode chemistry controls much of a cell’s voltage, energy, cost, and safety. This chapter covers LCO, LMO, NMC, NCA, LFP, and how crystal structure changes performance.

Graphite is the standard anode because it stores lithium reversibly and at low voltage. You will see how graphite particles, coatings, porosity, and the SEI layer affect real cells.

Electrolytes carry lithium ions, separators prevent short circuits, binders hold coatings together, and metal foils collect current. This chapter shows why “inactive” materials often decide safety and lifetime.

Cylindrical, pouch, and prismatic cells solve the same problem in different packages. You will compare their mechanical strength, heat flow, swelling behavior, cost, and pack design tradeoffs.

Charge and discharge curves reveal state of charge, usable capacity, polarization, and aging. You will practice reading voltage curves and linking their shape to chemistry and operating conditions.

Capacity fades because lithium inventory, active material, electrolyte, and conductivity are slowly lost. This chapter explains SEI growth, particle cracking, gas generation, corrosion, lithium plating, and calendar aging.

Thermal runaway begins when heat-producing reactions outrun heat removal. You will study abuse conditions, internal shorts, gas venting, flame risk, propagation, and the limits of extinguishing a battery fire.

Safe battery work starts with correct tools, personal protection, isolation, storage, labeling, and emergency habits. You will handle cells, connectors, meters, and chargers with practical caution.

Cyclers, temperature chambers, impedance meters, fixtures, and data loggers turn battery behavior into evidence. This chapter covers capacity tests, rate tests, pulse tests, EIS, leakage checks, and repeatable test plans.

Equivalent-circuit models turn voltage, resistance, capacitance, and state of charge into useful predictions. You will build simple models for runtime, voltage sag, heating, and control decisions.

State of charge, state of health, and state of power cannot be measured directly in normal use. This chapter covers coulomb counting, open-circuit voltage, Kalman filtering, impedance clues, and error correction.

A battery management system watches voltage, current, temperature, isolation, contactors, and faults. You will see how hardware and firmware keep a pack inside safe operating limits.

Cells age and charge differently, so packs need balancing. This chapter covers passive balancing, active balancing, top balancing, bottom balancing, and when balancing helps or hides deeper problems.

Heat changes power, aging, safety, and fast-charge limits. You will compare air cooling, liquid cooling, cold plates, heat pipes, phase-change materials, heaters, insulation, and thermal sensors.

Series strings raise voltage, parallel groups raise capacity, and busbars carry current. This chapter covers pack topology, fuses, contactors, precharge circuits, isolation monitoring, enclosures, service disconnects, and wiring choices.

Battery packs must survive vibration, shock, compression, swelling, water, dust, and service handling. You will connect mechanical design choices to safety, manufacturability, and repair.

Electrode manufacturing starts with powders, binders, solvents, mixing, coating, drying, calendaring, and slitting. This chapter shows how small process changes affect porosity, adhesion, loading, and cell performance.

Cell assembly brings electrodes, separator, electrolyte, tabs, seals, and casing together. You will follow winding, stacking, filling, wetting, formation, aging, grading, and the quality checks that catch weak cells.

Gigafactories depend on yield, traceability, contamination control, dry rooms, automation, and process windows. This chapter links manufacturing decisions to cost, scrap, reliability, and warranty risk.

Follow a real pack project from requirements to cell choice, electrical layout, thermal design, BMS settings, enclosure, tests, safety review, documentation, and release. You will see how tradeoffs become engineering decisions.

Fast charging is limited by heat, lithium plating, ion transport, voltage limits, and user expectations. This chapter covers charge profiles, preconditioning, anode potential, diagnostics, and practical ways to reduce damage.

High-nickel NMC and NCA cathodes raise energy density but demand tighter control of moisture, surface reactions, cracking, gas, and safety. You will see why these cells power long-range EVs and why they are harder to manage.

LFP cells trade some energy density for long life, lower cost, strong safety, and cobalt-free supply chains. This chapter covers the LFP revival, blade-style designs, LMFP, cold-weather limits, and pack-level gains.

Silicon can store far more lithium than graphite, but it swells, cracks, and consumes electrolyte. You will compare silicon oxide, silicon-carbon blends, prelithiation, binders, and the compromises behind today’s silicon-enhanced cells.

Solid electrolytes promise higher safety and can enable lithium-metal anodes, but interfaces, pressure, dendrites, and manufacturing are difficult. This chapter separates real progress from hype across sulfide, oxide, polymer, and hybrid designs.

Dry electrode coating can cut solvent use, energy cost, factory footprint, and drying time. You will see how fibrillated binders, powder handling, calendaring, and process control change electrode design.

Modern packs increasingly skip modules, use cells as structural elements, or integrate storage directly into a vehicle body. This chapter covers cell-to-pack, cell-to-chassis, blade cells, crash loads, service tradeoffs, and thermal propagation control.

Battery data now flows from cells, packs, vehicles, chargers, and cloud systems. This chapter covers fleet analytics, digital twins, predictive maintenance, anomaly detection, and the risks of bad data.

EV packs need high energy, fast charging, crash safety, cold-weather performance, long warranties, and careful thermal control. You will connect cell choices to range, power, charging networks, and pack service strategy.

Grid batteries care about cost per cycle, safety spacing, fire codes, round-trip efficiency, dispatch software, and long service life. This chapter covers containers, inverters, augmentation, degradation guarantees, and grid use cases.

Phones, laptops, power tools, drones, medical devices, and e-bikes each stress batteries differently. You will match chemistry, format, protection, charging, and certification choices to product needs.

Used batteries can be repaired, repurposed, recycled, or treated as hazardous waste depending on condition and economics. This chapter covers diagnostics, second-life packs, black mass, pyro, hydro, direct recycling, and design for recycling.

Lithium, nickel, cobalt, manganese, iron, graphite, copper, and electrolyte chemicals have real supply risks. You will connect material choices to cost, mining, refining, geopolitics, labor concerns, and environmental impact.

Battery work is shaped by UN 38.3, UL, IEC, SAE, ISO, DOT, IATA, OSHA, NFPA, local fire codes, and product-specific rules. You will know which tests, labels, documents, and safety duties appear in real projects.

Failures leave clues in voltage logs, swelling, heat marks, teardown evidence, CT scans, microscopy, and chemistry tests. This chapter teaches a careful path from symptom to root cause without jumping to blame.

Lithium-ion work spans cell materials, manufacturing, pack engineering, BMS, testing, safety, recycling, sales engineering, and research. Finish by mapping roles, proof-of-skill projects, useful certifications, lab habits, conferences, standards, and ways to keep current.