Electric Vehicles
This page answers your questions about electric vehicles (EVs), whether you own one or are just curious. It covers various EV topics, including EV fundamentals, key factors affecting charging speeds, and where you can charge your EV on the Brandeis campus.
Campus Charging Locations
Types of Electric Vehicles
There are three kinds of electric vehicles. People commonly call EVs Battery Electric Vehicles (BEVs). However, it is also important to note that other types of electric cars exist, namely Hybrid Electric Vehicles and Plug-in Electric Vehicles, which will be discussed in further detail below.
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Unlike gasoline-powered cars, battery electric vehicles (BEVs) do not have an engine that uses gasoline. Instead, they use an electric motor powered solely by their battery. BEVs are silent and emission-free. Depending on the model and year, BEVs typically travel 75 to 402 miles on a single charge, and that number is rapidly increasing.
The Tesla Model 3, Chevy Bolt, and Nissan LEAF are examples of battery electric vehicles.
A second type of electric vehicle caters to individuals who enjoy the benefits of gasoline and electric powertrains; this is known as a plug-in hybrid electric vehicle, or PHEV for short, offering a unique driving experience. The 10-40 mile electric range standard in PHEVs is well-suited to commuters with home or public charging access. When the electric car’s battery is empty, it switches to hybrid mode using its gasoline engine.
The Chevrolet Volt, Toyota Prius Plug-in, and Kia Optima Plug-in are examples of PHEVs.
Hybrid electric vehicles (HEVs) offer an alternative for those not quite ready for a fully electric car.
The power source for HEVs is an internal combustion gasoline engine, also known as ICE. Some HEVs use the ICE to recharge the battery and drive the transmission; others use it only for recharging. In both cases, HEVs are gasoline-powered cars that produce significantly fewer pollutants than conventional gasoline cars. These are perfect for anyone wanting to save money on fuel or reduce their environmental impact.
The Toyota Prius, Honda Insight, and Ford Fusion Hybrid are some examples. Since HEVs aren’t plug-in vehicles, they can’t charge at EVgo or any other public charging station.
EV vs Gas: Four Key Differences
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Charging an electric vehicle is like charging a phone. Phone charging habits vary among people, and EV charging habits vary among drivers. Many people plug in their phones overnight. Some people charge their devices at their desks at work. Others conveniently charge their devices in their cars, homes, airports, and anywhere else. Fortunately, EV charging is just as versatile as phone charging, with many options available.
Electric vehicles presently require a longer charging time than gasoline cars need for refueling. However, the time difference is getting smaller. The world of electric vehicles is diverse and constantly changing. Initially, most EV owners charged their vehicles at home or work overnight. Across the country, an extensive network of fast chargers is enabling EV drivers to charge during quick stops for errands like grocery shopping or appointments, all within 15-45 minutes.
Gasoline and fossil fuels are finite resources. Burning fossil fuels produces smog, greenhouse gases, and other harmful pollutants to human health.
Battery-electric vehicles don’t produce any emissions at the point of use. Compared to gasoline-only vehicles, PHEVs and HEVs produce far fewer tailpipe emissions due to their improved fuel efficiency, even when running on gasoline.
Many people mistakenly believe electric cars produce as many harmful emissions as gasoline-powered cars, considering vehicle production and electricity generation. Electric vehicles produce fewer emissions. Electric cars will become even cleaner as the power grids increasingly utilize renewable energy.
Electric vehicles are cheaper to fuel than gasoline cars, averaging about 35% less. Several factors determine the price of gasoline, including the cost of crude oil, taxes, and international supply and demand. The cost of electricity is mainly determined by the level of consumption. The electricity grid is strained when many people use electricity simultaneously, adding to the charging costs. As electric vehicles and charging infrastructure develop, new advancements are constantly emerging to improve charging speed and reduce costs.
Four Types of Connectors
Different countries have different power outlets. Electric cars are similar. Different EV manufacturers use different charging connectors due to their worldwide distribution. Luckily, EVgo works with most of them. However, you must still identify your EV’s charging connector to charge it correctly.
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CHAdeMO, short for “Charge de Move,” is a quick charging system developed mainly by Japanese carmakers and industry groups. Nissan and Mitsubishi, for example, favor the CHAdeMO standard.
While the CCS connector is an open standard adopted by vehicle manufacturers worldwide, its use is most strongly linked to carmakers based in North America and Europe. North American passenger EVs, excluding Teslas, will all use CCS connectors.
The North American Charging Standard (NACS), now standardized as SAE J3400, is a connector for fast EV charging. Its compact design is becoming increasingly popular within the industry. EVgo’s fast-charging network will soon include NACS connectors, benefiting more electric vehicle drivers.
This connector works with Level 1 and Level 2 AC chargers. Compared to DC fast charging, Level 1 and Level 2 charging are much slower and better suited for more extended charging periods at home or in the workplace. All electric vehicles, except Teslas, use the SAE J1772 connector (or “J Plug”) for AC charging; Teslas have an adapter for this connector.
EV Adapters
Adapters convert power from one standard to another for charging. Despite numerous industry standards, few compatible adapters are available. To avoid potential faults and maintain functional safety, it’s best to prevent adapters, as they add complexity to the electrical connection between the EV and the electrical vehicle supply system (EVSE).
Approved Adapters
To guarantee the safety of EVs and EVgo charging equipment, only adapters made by the automaker designed for your specific vehicle make and model are allowed.
Once available, certified adapters will have a UL mark. Third-party adapters that an automaker does not make are not approved for use, as they may damage chargers and vehicles.
Common Mistakes to Avoid
Do not use an AC adapter on a DC fast charger. Tesla AC adapters are not designed for DC charging. Forcing one into a DC CCS1 plug can damage the charging connector and prevent charging.
Do not use third-party or outdated adapters. Adapters designed for older EV models or purchased from unauthorized sellers may be incompatible with newer vehicles, leading to overheating, short circuits, or reduced charging speeds.
Do not attach multiple adapters to a single charging connector. Doing so can overload the connector, exceed power limits, and damage both the EV and the charging station.
For details on adapter requirements, refer to EVgo’s Terms of Service.
Charging Safety
Using the correct adapter ensures a safe charging experience for all EVgo customers. Always inspect your adapter before use and make sure it is securely connected to both your vehicle and the charger before starting a session.
Frequently Asked Questions
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Electric vehicle charging times depend heavily on the charger, battery size, and charging speed. A standard outlet will take 24 hours or more to fully charge your electric vehicle, while DC fast charging can take between 30 and 60 minutes. A home charger will typically charge your vehicle in four to ten hours.
- Battery Capacity: Larger batteries require more time to charge.
- Charger Speed: Higher kW chargers provide faster charging
Here’s the breakdown:
- Level 1 charging is the slowest, using a standard 120-volt outlet. A full charge can take 24 hours or more, with some EVs needing even longer.
- Level 2 charging, done with a 240-volt charger, is faster. Based on U.S. standards, expect the battery to charge fully within 4 to 10 hours. Rapid charging of DC provides the quickest charging times using high-voltage DC chargers. This translates to most electric vehicles being able to charge from empty to full in 30-60 minutes, providing a range of 150-400 miles per hour.
The charging speed of an electric vehicle (EV) battery slows down as it approaches full capacity for several reasons. The car's battery management system (BMS) controls the charging process to protect the battery cells, and the charging rate is typically reduced as the battery approaches 80% or higher. The battery’s internal resistance increases as it fills up, contributing to the slower charging rate.
Battery Management System (BMS) Protection:
The BMS is designed to prevent overcharging, which can damage the battery cells. As the battery nears full capacity, the BMS reduces the current to avoid exceeding the cell’s voltage limits.
Internal Resistance Increase:
As the battery fills with charge, the internal resistance increases. This resistance makes it harder for the battery to accept the same amount of current, causing the charging rate to slow down.
Charging Curve:
EVs have a specific charging curve that is influenced by the battery’s state of charge and temperature. This means the charging rate is not constant throughout the process and will naturally decrease as the battery gets fuller.
Temperature:
Battery charging speed is also affected by temperature. Extreme temperatures (hot or cold) can slow down charging, while optimal temperatures (around 68°F) allow for faster charging.
In essence, the charging speed is not a linear process. It’s designed to be slower as the battery approaches full capacity to protect the battery cells and manage the battery’s internal resistance and temperature.