EV Charging Glossary
Every EV charger screen, dashboard, and charging app uses technical terms that can be confusing. Here they are in plain language. Find the term you saw and understand what it means.
Power and Energy
kW (Kilowatt)
A unit of power that measures how fast energy flows into your EV battery during charging.
kWh (Kilowatt-hour)
A unit of energy that measures how much electricity is stored in your battery or delivered during a charging session.
Amp (Ampere)
A unit of electrical current that measures how much electricity is flowing through the charging cable at any moment.
Volt (Voltage)
A unit measuring electrical pressure that pushes current through the charging cable and into your battery.
Watt
The base unit of electrical power, equal to one volt multiplied by one amp.
AC (Alternating Current)
The type of electricity from the power grid, used for slower home and destination charging where the car's onboard charger converts it to DC.
DC (Direct Current)
The type of electricity that batteries store, used in fast chargers that bypass the car's onboard charger to charge the battery directly.
SoC (State of Charge)
Your battery's current charge level shown as a percentage, like a fuel gauge for your EV.
SoH (State of Health)
A percentage indicating how much of your battery's original capacity remains after use and aging.
Charging Curve
A graph showing how your car's charging speed changes from empty to full, typically fast at low battery and slower as it fills up.
Taper
The gradual reduction in charging speed as your battery fills up, especially above 80% state of charge.
Peak Power
The maximum charging speed your car can accept, typically reached briefly at a low state of charge under ideal conditions.
Ramp-Up
The initial period at the start of a DC fast charging session when power gradually increases from low to peak.
Power Sharing
When two or more charging stalls share a single power cabinet, splitting the available power between connected vehicles.
Load Balancing
A system that distributes available electrical power across multiple chargers at a site based on demand and grid limits.
Connectors and Plugs
CCS2 (CCS Combo 2)
The standard DC fast charging connector used across Europe, combining AC Type 2 and DC pins in one plug.
Type 2 (Mennekes)
The standard AC charging connector in Europe, used at home wallboxes, workplace chargers, and destination chargers.
CHAdeMO
A Japanese DC fast charging standard that is being phased out in Europe in favor of CCS2.
NACS (North American Charging Standard)
Tesla's charging connector, now adopted as the North American standard. Known as the Tesla connector in Europe.
GB/T
China's national EV charging standard, used for both AC and DC charging within the Chinese market.
Three-Phase AC Charging
AC charging using three electrical phases, delivering up to 22 kW (or 43 kW in rare cases) for significantly faster AC charging.
Single-Phase AC Charging
AC charging using one electrical phase, typically delivering 3.7 kW to 7.4 kW, common at home outlets and basic wallboxes.
Plug & Charge (ISO 15118)
Automatic authentication and payment when you plug in your cable, with no app, card, or screen interaction needed.
MCS (Megawatt Charging System)
A new charging standard designed for heavy-duty electric trucks, capable of delivering over 1 megawatt (1,000+ kW) of power.
NACS Adapter
A physical adapter that lets a car with one connector type (like CCS1) plug into a Tesla NACS Supercharger.
CCS1 (CCS Combo 1)
The DC fast charging connector standard used in North America, combining a Type 1 (J1772) AC connector with DC pins.
ChaoJi
A next-generation ultra-high-power charging connector being developed jointly by China and Japan for global harmonization.
Pantograph Charging
An overhead or roof-mounted charging system for electric buses and trucks, using an automated arm that connects without driver intervention.
Protocols and Standards
OCPP (Open Charge Point Protocol)
An open communication standard that lets charging stations talk to their management software, regardless of hardware brand.
ISO 15118
An international standard defining how EVs and chargers communicate, enabling features like Plug & Charge and smart charging.
Autocharge
A simplified automatic charging start that identifies your car by its MAC address, without the full security of Plug & Charge.
eRoaming
A system that lets you use one charging app or card across multiple charging networks, similar to mobile phone roaming.
Hubject
The largest eRoaming platform in the world, connecting hundreds of charging networks so drivers can charge across networks with one account.
GIREVE
A European eRoaming platform, strongest in France, that connects charging networks and enables cross-network access for drivers.
RFID (Radio Frequency Identification)
A contactless card or key fob you tap on a charger to start a session, commonly used by European charging networks.
eMSP (e-Mobility Service Provider)
A company that provides EV drivers with access to charging networks through a card, app, or account, handling payment and roaming.
Pilot Signal (Control Pilot / CP)
A communication signal between the charger and car that negotiates charging parameters and ensures safety before power flows.
Proximity Signal (Proximity Pilot / PP)
A signal that tells the car a charging cable is physically connected and what current rating the cable supports.
Bidirectional Charging
The ability to both charge your EV battery and discharge it, sending stored energy back to your home, the grid, or external devices.
V2G (Vehicle-to-Grid)
Technology that lets your EV send stored energy back to the electrical grid, potentially earning you money during peak demand periods.
V2H (Vehicle-to-Home)
Technology that lets your EV power your home during outages or peak electricity rates using a bidirectional charger.
Charging States
Preconditioning
Your car warming (or cooling) the battery to the ideal temperature before you arrive at a fast charger, so you charge faster.
Idle Fee
An extra charge applied when your car stays plugged in after charging is complete, designed to free up chargers for other drivers.
Charging Session
One complete charging event, from the moment you plug in and authenticate to when you unplug and leave.
Charge Limit
The maximum state of charge percentage you set in your car, telling it to stop charging when it reaches that level.
Scheduled Charging
A setting that delays the start of charging to a specific time, often used to charge during cheaper off-peak electricity hours.
Departure Time
A setting that tells your car when you plan to leave, so it finishes charging and preconditions the cabin by that time.
Regen (Regenerative Braking)
Your EV's ability to recover energy when you slow down or brake, converting motion back into electricity stored in the battery.
Range Estimate
The distance your car's dashboard predicts you can drive on the remaining battery charge, based on recent driving patterns.
Liquid-Cooled Cable
A charging cable with built-in coolant circulation that prevents overheating during high-power DC fast charging sessions.
Power Module
A replaceable electronic unit inside a DC fast charger that converts AC grid power to DC power for battery charging.
Power Cabinet
The large enclosure containing the power electronics that convert grid AC power to DC for one or more charging dispensers.
Satellite Unit (Satellite Charger)
A compact charging dispenser that connects to a separate power cabinet, allowing flexible installation and dynamic power sharing.
Contactors
Heavy-duty electrical switches inside the charger and car that connect and disconnect the high-voltage DC power circuit during charging.
GFCI / RCD (Ground Fault Protection)
A safety device that instantly cuts power if it detects electricity leaking to ground, protecting against electric shock during charging.
Transformer
Electrical equipment that converts high-voltage grid power to the lower voltage levels needed by EV chargers at a charging site.
Curtailment
Deliberately reducing or stopping EV charging when the electrical grid is under stress, to prevent overloading the power supply.
Peak Shaving
Reducing the highest power peaks at a charging site, often using battery storage or load management, to lower electricity costs.
Behind-the-Meter
Energy equipment (batteries, solar panels) installed on the customer side of the electricity meter, reducing grid dependency and costs.
Payment and Billing
Ad Hoc Charging
Paying for a charging session without a subscription or account, typically by scanning a QR code or tapping a bank card.
Roaming Card
A single RFID card from one provider that works across many different charging networks through eRoaming agreements.
Contactless Payment
Paying for charging by tapping your bank card or phone on the charger's payment terminal, like paying at a shop.
Per-kWh Pricing
A pricing model where you pay for the exact amount of energy delivered to your car, measured in kilowatt-hours.
Per-Minute Pricing
A pricing model where you pay based on how long you are connected, common at DC fast chargers in some markets.
Session Fee
A flat fee charged at the start of each charging session, on top of energy or time-based costs.
Blocking Fee
A per-minute charge applied when your car stays connected after charging finishes, same concept as an idle fee.
Dynamic Pricing
Charging prices that change based on time of day, electricity costs, or charger demand, sometimes displayed in the app before you start.
Roaming
Using one charging provider's account or card to charge at another network's stations, with the billing handled between providers.
EMV (Contactless Bank Card Payment)
The global standard for chip-based bank card payments, increasingly required on public EV chargers for direct tap-to-pay transactions.
Plug & Charge Certificate
A digital certificate stored in your car that automatically identifies you and authorizes payment when you plug into a compatible charger.
MSP (Mobility Service Provider)
Another term for eMSP, the company that provides your charging account, app, or card for accessing multiple charging networks.
Subscription Pricing
A monthly fee that gives you access to lower per-kWh charging rates at a specific network, similar to a loyalty discount.
Pre-Authorization
A temporary hold placed on your bank card when you start a charging session, released and replaced with the actual charge amount afterward.
Activation Fee
A one-time fee some networks charge when you first register or order an RFID card to access their chargers.
Flat-Rate Pricing
A pricing model where you pay a fixed amount per charging session regardless of how much energy you receive.
Demand Charge
An electricity bill component based on the highest power peak drawn during a billing period, a major cost factor for charging station operators.
Time-of-Use Rate (TOU)
An electricity pricing structure where the cost per kWh changes based on the time of day, with cheaper rates during off-peak hours.
Battery Technology
LFP (Lithium Iron Phosphate)
A battery chemistry that tolerates regular full charges, lasts longer, but has slightly less energy density than NMC batteries.
NMC (Nickel Manganese Cobalt)
A battery chemistry with high energy density, offering more range per weight but benefiting from keeping daily charges below 80-90%.
400V Architecture
The standard voltage platform used in most current EVs, supporting DC fast charging up to about 200 kW.
800V Architecture
A high-voltage EV platform enabling faster charging speeds, up to 350 kW, by reducing current and heat at the same power level.
Heat Pump
An efficient heating system that warms the cabin (and sometimes the battery) using less energy than a traditional resistive heater.
BMS (Battery Management System)
The electronic controller that monitors and protects your EV's battery, managing temperature, charging speed, and cell balance.
Depth of Discharge (DoD)
How much of your battery's total capacity you use before recharging, expressed as a percentage.
Cycle Life
The number of complete charge and discharge cycles a battery can handle before its capacity drops below a specified threshold.
Cell Balancing
The process of equalizing voltage across all cells in a battery pack so they charge and discharge evenly for maximum capacity and longevity.
Thermal Runaway
A dangerous chain reaction inside a battery cell where rising temperature causes further heat generation, potentially leading to fire.
Calendar Aging
The gradual loss of battery capacity over time, regardless of how much you drive or charge, caused by chemical processes inside the cells.
C-Rate
A measure of how fast a battery charges or discharges relative to its capacity, where 1C means fully charging or discharging in one hour.
Nominal vs. Useable Capacity
The total physical battery capacity versus the portion your car actually lets you use, with a buffer reserved to protect battery health.
Solid-State Battery
A next-generation battery technology that replaces the liquid electrolyte with a solid material, promising faster charging, more range, and improved safety.
Networks and Infrastructure
CPO (Charge Point Operator)
The company that owns, installs, and maintains the physical charging stations you use.
EVSE (Electric Vehicle Supply Equipment)
The technical term for the physical charging unit, including the housing, connector, cable, and electronics.
Destination Charger
A slower AC charger installed at hotels, restaurants, or parking garages, designed for charging while you are parked for hours.
Rapid Charger
A DC fast charger delivering 50 kW or more, capable of adding significant range in 30-60 minutes.
Ultra-Rapid Charger
A high-power DC fast charger delivering 150 kW or more, capable of adding 200+ km of range in 15-20 minutes.
Charger Availability
Whether a specific charger is free to use right now, shown as available, in use, or out of service in charging apps.
Uptime
The percentage of time a charger is operational and available for use, a key reliability metric for charging networks.
Smart Charging
Technology that adjusts charging speed and timing based on grid demand, electricity prices, or renewable energy availability.
Interoperability
The ability for any EV to charge at any public charger and pay with any provider, without compatibility barriers.
Load Management
A system that controls the total power drawn by chargers at a site to stay within the building's or grid's electrical capacity.
Charging Hub
A large, purpose-built charging location with many fast chargers, amenities, and dedicated parking, similar to a petrol station for EVs.
White-Label Charger
A charger manufactured by one company but branded and operated under another company's name and network.
Charger Utilization
The percentage of time a charger is actively delivering energy to a vehicle, a key business metric for charging network operators.
OpenADR (Open Automated Demand Response)
A communication standard that lets the electricity grid signal chargers to reduce or shift power consumption during peak demand.
Grid Connection
The physical electrical link between a charging site and the power grid, whose capacity determines the maximum total power available for charging.
Vehicle Terms
Onboard Charger
The component inside your car that converts AC electricity from the grid into DC electricity that the battery can store.
Charge Port
The socket on your car where the charging cable plugs in, usually behind a small door on the front fender, rear fender, or nose.
WLTP Range
The official European range rating based on a standardized test cycle, typically optimistic compared to real-world driving.
Real-World Range
The actual distance your EV can travel on a full charge under normal driving conditions, usually less than the official WLTP rating.
Consumption (Wh/km)
The amount of energy your car uses per kilometer driven, the EV equivalent of fuel economy.
Drivetrain (FWD/RWD/AWD)
Which wheels receive power from the motor(s), affecting traction, efficiency, and performance.
One-Pedal Driving
A driving mode where lifting your foot off the accelerator causes strong regenerative braking, letting you speed up and slow down with one pedal.
Range Mode
A vehicle setting that reduces energy consumption by limiting climate control, seat heating, and other accessories to maximize driving range.
Eco Mode
A driving mode that softens acceleration, increases regenerative braking, and optimizes systems for maximum energy efficiency.
Valet Mode
A vehicle setting that limits top speed, acceleration, and access to personal data when someone else drives your car.
Battery Preheating
Warming the battery to optimal temperature before fast charging, either automatically via navigation or manually through the car's settings.
V2L (Vehicle-to-Load)
Using your EV's battery to power external devices like appliances, tools, or other electric vehicles through a built-in outlet.
Charge Rate Setting
A vehicle setting that lets you limit the maximum charging current or power your car draws from an AC charger.
Charge Port Light
The colored LED indicator around your car's charge port that shows charging status through different colors and patterns.
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