Types of EV Batteries
Hybrid, plug-in hybrid, and all-electric vehicles all use battery packs to power their electric motors. The type of battery used varies depending on the type of vehicle you are driving. Hybrids tend to have the smallest batteries, while plug-in hybrids (PHEVs) and fully-electric vehicles (EVs) have larger batteries. Unlike the battery packs in your phone or laptop, EV batteries have sophisticated cooling systems and battery-management software to ensure they deliver performance and range for many years of reliable service. Indeed, U.S. law requires battery warranties to be at least eight years or 100,000 miles; most batteries used in moderate climates will last well past 15 years, and often beyond the life of the vehicle itself.
The different types of batteries being used today are lithium-ion, nickel-metal hydride, lead-acid, and ultracapacitors. New technology such as solid-state batteries are also just a few years away from being introduced to the mass market. They have the potential to significantly enhance range and performance of EVs – and will change the way people think about electric cars. For one thing, they could offer a range of over 500 miles on a single charge.
Lithium-Ion Batteries
Most of today’s EVs use lithium-ion battery packs. It is the same technology used in smartphones and laptop computers and are known for having a high power-to-weight ratio. Very efficient and offering excellent high-temperature performance, they are currently the best option for holding a stable charge and are recyclable. However, lithium-ion batteries have come under a lot of scrutiny for the not so eco-friendly way the materials for them are mined. For instance, it takes 500,000 gallons of water to refine one ton of lithium.
There are many different types of lithium-ion batteries, with different chemical compositions. A newer type of lithium-ion battery, called lithium iron phosphate (LFP for short) contains fewer critical minerals, making them cheaper and more environmentally-friendly to manufacture. LFP batteries don't offer quite the same ability to rapidly charge and discharge, but they're making mainstream EVs more affordable than ever.
Nickel-Metal Hydride Batteries
You’ll mostly find nickel-metal-hydride (or NiMH) battery packs in hybrid vehicles that combine a gasoline engine with electric motors. These cars use gasoline power to recharge the onboard battery. Nickel-metal hydride batteries generally last longer than lithium-ion batteries and are safe to use. The drawbacks are that they are expensive to produce, generate a lot of heat at high temperatures, and have a high discharge rate. Most modern hybrids have switched from NiMH to higher-performing, lighter, and more compact lithium-ion batteries.
Lead-Acid Batteries
Lead-acid batteries are the kind of 12-volt batteries used in gasoline-powered cars to start the motor. They have been around a long time, and are inexpensive and safe to use. However, lead-acid batteries have a relatively short life, and don’t perform well in cold weather. This sort of battery is only used in EVs to power supplemental auxiliary features; providing backup power to power steering, brake boosting, and to power the safety features in EVs. They cannot actually power the electric motors themselves.
Ultracapacitors
Like lead-acid batteries, ultracapacitors are used as secondary storage devices and help to level the load of lithium-ion battery packs. They basically store polarized liquid between an electrode and an electrolyte. Ultracapacitors also give EVs an extra boost of power during acceleration.
Solid-State Batteries for Electric Cars
In the next few years, solid-state batteries may well be the battery of choice for electric cars. They can reduce the carbon footprint of EV batteries by nearly 40 percent. Solid-state technology uses solid ceramic material instead of liquid electrolytes to carry the electric current, making the batteries cheaper, lighter, and faster to charge. BMW and Ford are testing the batteries now for use in 2025 vehicles. Solid-state batteries are also capable of having a driving range of 500 miles, eliminating “range anxiety.”
