How to Prolong Electric Car Battery Charge in Winter

One of the biggest things people worry about with their new electric car is the single-charge range of the lithium-ion battery pack. Not only do people worry about the battery running out of juice with no hope of charging in sight during a warm sunny summer’s day, but they fear it even more happening in the winter as we are told that winter is like death to an EV battery.

It’s true that the overall performance of EV batteries does suffer in the cold weather, and that’s true for any device powered by a lithium-ion battery, including your smartphone. This doesn’t mean, however, that there’s nothing you can do to prolong the battery’s life and safeguard it against the effects of the cold.

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Background: Why Does Cold Affect Batteries?

The main reason for lithium-ion batteries performing much less well in cold weather is that the low temperatures cause the chemical reactions within the battery to happen at a much slower pace. It’s not a new problem for car owners, in fact. Most people who have experienced difficulty starting their internal combustion engine car in the morning do so during the winter, or at least it seems to become more likely on a winter’s morning. This is because the 12-volt battery is also suffering in the winter weather.

As long as cars rely on batteries of any sort, the winter weather will continue to be a problem, but their resistance is increasing as materials improve and battery construction becomes more sophisticated. After all, countries like Norway that are adopting electric cars at a rapid pace wouldn’t be doing so if there was no hope for them to work during the winter months. So, what can we do to keep batteries better charged in winter?

1. Keep Battery Charge Between 20 and 85 Percent

This has become the standard advice for maintaining good battery health, only charging your car to full before you undertake a very long journey, and never allowing the battery life to deplete fully or ideally never below 20 percent. Recharging from zero and all the way to 100 is not good for the chemical balance in the battery cells if it becomes a habit.

So, when charging the battery overnight or using a public charging station, use the settings in your car or on its smartphone app to limit charging to 85 percent. This is now possible on virtually all EVs, and even if not, you can monitor the charge progress from your smartphone and then unplug when the time is right.

2. Park in a Garage or Other Indoor Structure if Possible

Parking indoors will ensure that your car and battery don’t get too cold, especially during the night when temperatures drop really low. This makes it easier to warm the car and battery to optimum temperature before setting off in the morning since the system is working from a warmer starting point.

When you’re out and about, it’s also a good idea to favour indoor parking options wherever possible in the winter months, even if it costs a little more. It will help keep the battery closer to ambient temperature while you leave sitting in its parking spot.

3. Precondition the Car Before Setting Off

One of the nice features of many electric cars is how much you can with the car remotely from a related smartphone app. One such thing is preconditioning the vehicle remotely so while you’re preparing breakfast or taking your morning shower, the car can be steadily getting warmed up and ready to go in the garage. This wasn’t possible with traditional petrol cars, not because of the lack of remote features but because leaving the car warming in the cold garage (with choke on, normally) would quickly fill the garage with toxic fumes.

Preconditioning usually means getting the car’s battery, passenger cabin and seating warmed up so that the vehicle feels comfortable and ready to drive when the owner gets in. On some models, you can pre-set the car to do this automatically at a determined time so you needn’t worry about setting it off in the morning.

4. Make Use of Heated Seating

While many new-generation EV models are starting to use more efficient heat pump technology, most EVs still use resistance heaters as the main way to provide additional heat to the passenger cabin. This can be a huge drain on the battery, but in the absence of a combustion engine generating all that lovely extra heat, what should people do?

Well, a good alternative if possible is to make use instead of features like heated seating, which are much less of a drain on the battery compared to the resistance heater. Efficiency is always improving in newer models, but if you can use your heated seat to warm you instead of using the battery to warm air around you, then you can save a lot of energy in the harsh winter months.

5. Use Power-Saving Mode

It’s a pretty standard feature on electric vehicles to have some kind of power-saving mode. It’s usually called “Eco Mode” or something similar to that. Activating this will keep battery power-consuming systems to a minimum and optimise power usage. When the cold of the weather is working against you, having eco-mode as your standard drive setting is a good idea.

A general policy of not over-taxing the battery with your driving is a good policy in winter. The winter roads are typically unsafe for fast acceleration and harsh braking anyway, but just in case the roads are clear but the weather is very chilly, keep driving as steady and as even as possible.

6. Maintain Proper Tyre Pressure

Cold temperatures affect tyre pressure regardless of what kind of car you drive, with every 5-6 degrees Celsius drop in temperature losing your tyres about 1 PSI in pressure. Therefore, the colder it gets compared to an ambient temperature of about 20 degrees, the lower your tyre pressure is. That’s not good news for any car, but it affects EVs even more.

Research from ExxonMobil showed that proper tyre pressure in your EV can actually increase the efficiency of your car’s lithium-ion battery pack by 3-7 percent. Therefore, keeping an eye on falling tyre pressure and topping up where necessary is a good idea.