Why solar charging prolongs the battery life for electric cars

First, some numbers: Lightyear One has a 60kwh lithium-ion battery, created from cylindrical cells, with a high energy density.

Also, because a range of 725km cannot be met if the vehicle is hampered by unnecessary weight, the battery of Lightyear One also needs to be lightweight. Luckily for us, our solar electric car is very efficient, meaning you don’t need excess power to operate it - hence the small battery system.

By having a lightweight battery, a positive feedback cycle is put into motion: a lighter battery means a lighter frame, which leads to a lighter car, which leads to a more efficient car, which leads back to not needing a lot of energy to power it. This results in the most range per kWh battery, compared to other electric vehicles.

Lightyear One is chargeable through 4 different methods: regenerative braking, solar power, normal outlet power, and fast charging, from a specialised station. Fast charging, done in excess, can be very damaging to the battery. Charging from the sun, through the five square meters of solar cells that cover the top of the car, is a slow type of charging. By making sure Lightyear One gets most of its energy through this form of (relatively) slow and steady charging, the battery life is prolonged.

This brings a major advantage to our users, who won’t need to worry about loss of range over time.

It’s also good to note that Lightyear One is researching safety features, as to how to develop a system where we keep only one single cell from becoming too hot. By containing the temperature on a cell level, we can prevent further damage to the whole vehicle, by directly inserting a fire-retardant foam into the battery.

Of course, Tom will explain more in-depth about the Lightyear One battery in the video, as well as cover the culture of Lightyear and what makes working in the Lab a great experience.