Electric car batteries that charge in 10 mins
Engineers claim to have developed a battery technology for super-quick charging of electric vehicles…
A team of engineers have developed a technology which enables lithium-ion batteries for electric vehicles to drive for up to 300 miles from a 10 minute charge.
The solution the engineers used was to rapidly heat and cool the temperature sensitive batteries before any damage could occur while they’re hot.
The technology, developed at Pennsylvania State University in the USA, also claims to protect battery life. It provides up to 2,500 charges or half a million miles of use, with less than 10% battery life loss.
This could alleviate the problem of charging time, which along with range is one of the two major performance limitations of electric vehicles today. Both are a significant source of anxiety for drivers who are worried about running out of power, spending too long charging or not finding a charging point at all.
Despite car manufacturers’ best attempts, charging times are still a huge issue, with the average modern electric vehicle taking over an hour to receive a full charge - which might only provide 300 miles of range.
Although fast-charging of lithium-ion batteries has been possible for many years, the available methods significantly reduce battery life. The issue is temperature-induced chemical reactions, which can reduce the battery life by 20% after as few as 50 charges.
These unwanted chemical reactions cause metallic lithium to coat the negative terminal, or anode, of the battery cell. This means that the lithium is no longer being used to store energy.
The engineers from Penn State tackle the trade-off between battery life and charging speed by controlling the temperature of the battery during fast-charging, so that the cells within the battery degrade as little as possible, which would normally happen at sustained temperatures above 60°C.
Their technique differs from conventional methods by charging at a higher temperature using internal heating elements, and discharging at a cooler ambient temperature, eliminating the lithium coating problem.
Interestingly and counterintuitively, they found that charging at higher temperature meant that the battery cooled down more quickly. The internal heaters generated heat at a lower rate than the battery would have naturally itself, contributing to this effect.
The team claim that adding their technology would only increase lithium-ion battery cost by half a percent.
This - alongside the fact they are using conventional lithium-ion chemistry - makes a very promising commercial case for quick adoption by one of the many electric vehicle manufacturers.
The global adoption of electric vehicles therefore depends on reducing charging times so that they’re similar to filling up at a petrol station, whilst maintaining a similar price and performance compared to vehicles powered by internal combustion engines.
However, there are important questions of ethics and sustainability - many people are already concerned about the quantity of natural resources that would be required to sustain an electric vehicle economy, and whether these could be sourced in an ethical manner.