Important Shortcuts for Auto Service and Repairs

Crucial Metrics to Consider When Selecting an Electric Vehicle Battery

by Emilia Latvala

In March 2021, Australians purchased 411 electric cars, up from 248 bought in the whole of 2020. While the numbers are still low, it is a clear indication of the country's direction regarding the adoption of electric vehicles (EVs). One aspect that makes EVs popular is that the batteries are designed to last for long before replacement. However, mechanical damages can shorten an EV's battery life, warranting premature replacement. This article highlights critical metrics to consider when buying an EV battery.

Voltage 

It is essential to consider the operating voltage of an EV when purchasing a battery. Usually, the voltage is determined by a battery's electrode material. The best way to classify battery electrode materials is to categorise them as either aqueous-based or lithium-based. Aqueous electrodes, such as lead-acid, zinc-carbon, and nickel, have nominal voltages of at least 1.23V. On the other hand, lithium-based batteries rely on organic electrolytes that provide approximately 3.6 to more than 4V. Given that electric cars need enough voltage to operate the motor and electrical components, lithium-based batteries are the best choice due to their high voltage. However, you should remember that some EV batteries have a sloping discharge curve that could influence the cut-off voltage.

Temperature Range 

If you own an electric vehicle, you should drive it in any weather conditions without the battery dying. Notably, the operating temperature range of a battery is dictated by its chemical makeup. For instance, aqueous electrolyte-based batteries shut off when temperatures hit 0 C. On the other hand, lithium-based EV batteries running on organic electrolytes can efficiently operate at sub-zero temperatures. That said, the performance of lithium-based batteries drops gradually as temperatures fall further. Temperature also plays a critical role in the discharge of rechargeable lithium-ion batteries. For instance, when environmental temperatures are close to freezing, a trickle charge is recommended for lithium batteries. It helps prevent lithium dendritic plating problems, which reduces the risk of thermal runaway.

Battery Composition 

An electric vehicle's battery composition dictates the amount of power it can generate. Since different EVs have varying power needs, the battery composition depends on the type of car you own. Ultimately, EVs use batteries clustered into cells, modules and packs, where a cluster of cells forms a module, and a group of modules makes up a pack. Thus, the size of a battery pack depends on your preference. For instance, if the driving range is the most critical specification, you should choose a high-energy-density battery comprising more cells.

Contact a car battery provider to learn more.

Share