ASOTU Electric Vehicle Research

Electric vehicle (EV) technology has advanced rapidly since 1996. Today there are an increasing number of plug-in hybrid and battery EV options on the market. How do EVs even work, and why would anyone want one? We'll dive into answering everything you never knew you needed to know about electric vehicles. 

Abbreviation Station: 

• EV = Electric Vehicle
• HEV = Hybrid Electric Vehicle
• PHEV = Plug-in Hybrid Electric Vehicle
• BEV = Battery Electric Vehicle
• FCV = Fuel Cell Vehicle
• EVSE = Electronic Vehicle Supply Equipment
• ICE = Internal Combustion Engine

Types of EVS — 
Hybrid Electric Vehicles (aka HEVs)

• Powered by an internal combustion engine and one or more electric motors.
• The battery is charged by the engine and regenerative braking, not by plugging in.
• Increased fuel efficiency.
• First to reach the modern vehicle market.

Plug-in Hybrid Electric Vehicles (aka PHEVs)

• Powered by an internal combustion engine and electric motor that can be recharged with a plug. 
• Before swapping to hybrid mode, the vehicle can operate in all-electric mode until the battery is depleted (typically 20-40 miles per charge). 
• PHEVs typically require a much larger battery. 

Battery Electric Vehicles (aka BEVs)

• An electric motor that runs solely on a rechargeable battery, no ICE.
• A typical driving range of 150-400 miles.
• Has the largest batteries.
• Zero tailpipe emissions.

Hydrogen Fuel Cell Electric Vehicles (aka FCVs) 

• Powered by compressed hydrogen gas that feeds into an onboard fuel cell "stack" which transforms the chemical energy into electric energy.
• The energy then powers the electric motor.
• Zero tailpipe emissions, the only “waste” produced is pure water.
• Typical 300-400 mile range.

‍All about batteries —

We first need to understand the difference between batteries and cells. While the terms are sometimes interchangeable, they are different. 

‍Cells?

Multiple cells are combined to make up a battery pack. 

There are two main types of cells: primary (non-rechargeable) and secondary (rechargeable). 

Over their lifetime, secondary cells will go through multiple discharge-recharge cycles.

Types of EV batteries: 

• Lead-Acid Battery
• Nickel Cadmium Battery
• Nickel Metal Hydride Battery (most commonly used in hybrid EVs)
• Lithium Ion Battery (high energy density)

Battery Recycling:

As EVs become more prevalent, the battery-recycling market may expand. Thankfully, due to their relative newness, most EV batteries are far from the end of their lifecycle. 

While reclaimed material from batteries varies, Tesla says they retrieve about 92% of a battery's material for reuse with each battery returned. 

Eventually, the number of batteries in circulation could dramatically affect the affordability of producing and buying EVs. 

Chargers, aka EVSE (Electronic Vehicle Supply Equipment) 
Level 1 Charger. 

• Portable cord sets.
• Run off standard 120-volt household outlets.
• Provide 2-5 miles of range per hour.
• Most affordable.
• Limited in the daily range, it can supply.
• Ideal for PHEVs with smaller batteries or BEVs for drivers with short commutes.

Level 2 Charger. 

• Provide more energy per hour than Level 1, 10-20 miles of range per hour.
• Runs off 208 or 240 volts. 
• More expensive.
• Typically installed as permanent pedestal-style or wall-mounted units .
• Ideal for long-range BEVs and public charging stations.

DC Fast Charger. 

• Most expensive and fastest. 
• 60-80 miles of range per twenty-minute charge. 
• Mostly recommended to support occasional long-distance trips.
• Frequently charging with a high power level can lead to battery degradation.