Updated: Dec 5, 2021
It’s most likely that cabbies driving the new electric cabs, which are becoming more and more prominent all around the UK, will see a decrease in the number of miles achieved on a full charge.
But it’s not just electric vehicles that feel the affects of the outside temperature. The efficiency of all vehicles, even petrol and diesel ones, are all effected and this isn’t just limited to the additional drain of features like headlights and heaters.
However, the cold does impact electric vehicles in particular because battery cells relying on a series of chemical reactions, which occur best at around room temperature. It’s the cold winter weather that can slow these reactions down.
Let’s take the LEVC TX taxi as an example. This cab circulates coolant to maintain the battery pack at the most efficient temperature, maintaining efficiency and preventing any degradation of the cells. The side- effect is that these systems require energy to power them.
As well as the driving style and conditions, the type of usage also influences the extent to which cold weather can affect the overall efficiency. Every time the vehicle is switched off, the battery cools and must then be warmed back up, reducing the range dramatically. Fortunately, most taxis are on the go all day, ensuring the residual heat in the battery is maintained.
How does temperature affect charging times and is there a best time to charge?
The temperature of the battery also influences the speed at which electrical charge can be restored. When the outside temperatures drop, it’s necessary for the on-board battery management systems to restrict the flow of charge into the battery to prevent potential damage to the cells. The extent to which this occurs depends on factors such as the temperature of the battery pack, the state of charge and the power delivered by the charge post. As a rough guide, it’s realistic to expect a decrease in charging speed of up to 30% when comparing a warm summer’s day to a freezing winter one.
It’s also worth trying to charge your battery during, or at the end of, a shift when the battery is at operating temperature to speed up charge times.
How should can I best use the heating on my EV vehicle and what’s the most effective heating method?
When charging, whether overnight at home or on- street, think about setting a pre-conditioning timer to pre-warm the cabin using the mains electricity. This means energy isn’t taken from your battery to do the same job after you’ve driven away.
Another tip is when starting from cold, particularly if the pre-conditioning feature hasn’t been used, it’s possible to operate in ‘Save’ mode for a few minutes. This runs the petrol range-extender to maintain the charge in the battery, but has the useful side effect of generating heat as a by-product of the internal combustion process, which can be used by the systems on-board to warm up the battery and cabin.
Your taxi will be nice and warm and lost miles from your electric power source is a thing of the past!
Because there’s no source of hot air under the bonnet like in an internal combustion engine vehicle, the cabin heat must be generated electrically, and this uses energy from the drive battery. Instead of heating the air in the cabin, it’s much more effective to switch on your heated seat to maintain a comfortable temperature. If you do prefer to maintain the temperature throughout the cabin, recirculate the air so you’re not constantly drawing in cold air from outside and reduce the fan speed. If there are no passengers on board, it’s also possible to turn down or switch off the rear heating zone from the central touchscreen.