Wet Weather Driving

Tips for driving your electric car this winter

Is there anything more British than complaining about the weather?

Possibly not, other than talking about how rain automatically means more traffic jams. Driving in winter weather can be a bit of a headache, and here at Octopus Electric Vehicles we like to minimise those headaches, so voila: our guide to driving your EV in the cold and wet to get you through the winter!

There are a few things to be aware of when driving an EV in cold and/or icy conditions. Let’s quickly mention the torque, then talk about your tyres and their impact on range, before looking at the impact that cold conditions can have on your EV’s range.

We go into depth on a lot of the whys and wherefores below, but here is a quick summary if you’re looking for some quick top tips:

• Check your tyre pressure before leaving. The higher the pressure, the less your range will be impacted by the rain - keep that in mind when driving.
• Remember that even though in colder weather your pressure will drop quicker, you should never over inflate your tyres.
• Your range can shorten in the rain or in cold weather. With that in mind, make sure you’ve planned out a route with plenty of chargers along the way. Also be mindful of the fact that charging speeds may be slightly slower in the cold.
• Try to heat up your car before unplugging it in the morning - nominal battery temperature will ensure you can get the most range possible.
• Be gentle with any steering or wheel movements - they can have a bigger effect when it’s slippery out on the road!

When the ground is slippery, either caused by rain or ice/snow, it’s crucial to be far more gentle with your torque as there’s a significantly reduced straight line grip. Contrastingly to petrol, the power is there instantly in an EV - meaning that, whilst the computer can help you more quickly, you should still be very careful when turning and accelerating or braking at the same time. Try to use regenerative braking as much as possible, as this won’t lock the wheels.

Moving on to the tyres: If tyres are pushing water out of their path, they’ll require more energy to do so. Accordingly, this will affect your range and so it’s doubly important to map out any long journeys and ensure you’ve planned out where you’ll be able to charge. Your range will also be affected by your tyre pressure. The lower the pressure (to a point) the more grip your tyres have on the road, which means you’ll need to use more energy to push it forward. If your tyres have higher pressure, they’ll have less grip and therefore less rolling resistance. It’s always important to constantly monitor your tyre pressure to make sure you’re not wasting energy, but even more so in bad weather. When your tyres are already having to work harder to push water out of their path, having a sub-optimal tyre pressure can compound the effect on your range. Remember, tyre treads don’t create grip, they help to ship water, mud, snow etc. away from the bits of rubber that need to touch the road.

Your driving style can have a significant effect however, so remember that if you want to get the most use out of your tyres then an aggressive driving style is not your friend.

Returning to the topic of range, it’s important to be aware of the impact that cold weather can have on your electric car, and how you can mitigate the effects of this on your car’s range.

To help explain this, let's think about battery chemistry like a sponge inside a water bottle. The better the chemistry, the better the sponge. Think of the water in the water bottle as the electricity. As the sponge becomes cold, it gets stiffer and therefore harder to push energy out. Therefore, the sides of the water bottle become less flexible and, therefore, less able to get all the water out. As much as batteries don’t physically squeeze, the experience of a cold battery is extremely similar. This is why both Tesla and Kia - part of the Hyundai Group - have added heat pumps to their future vehicles.

Keeping the battery at a stable temperature helps prevent a reduction in battery efficiency, but obviously this takes energy to create. Heating your car to temperature while still plugged in over a long period of time (through its app or on the screen before leaving the car) will not only make it nice and cosy for when you get in, but will also get the battery to a working temperature before setting off on your journey, making it easier for the battery to give and receive energy. Heating your car this way will also mean that de-icing the front windscreen is a thing of the past, so there’s an added bonus! Once you set off on your journey, to get the most efficient performance it’s a good idea to turn off the AC and just use heated seats. One thing to bear in mind is that, if your battery is cold, it’s charge capacity will be lower. Whilst this means the battery will charge faster, the total range available will be reduced. This is definitely something to bear in mind in the colder months, as you don’t want to be caught out by reduced range! Again, making sure the battery is warm when you charge it is a great way to mitigate this.