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Can I Leave My EV Plugged In Overnight?

Now that it is official that electronic vehicles (EVs) can be run more affordably than fossil fuel options, we can expect an even greater surge in EV car ownership in the coming years. It really does just make more sense from a financial standpoint and in the interest of the environment.

In making this switch, there is something of a learning curve to adapt to. For many EV owners, charging issues are paramount as this is what takes the place of previously being able to just fill up the tank at a service station. While commercial charging stations at parking lots, shopping centres, and service stations have become more prevalent, taking care of this task at home is still most convenient.

How Home Charging Works

Overnight charging on a home charging station is the standard practice. Once people get home, it is just a matter of plugging in the ev charging cable and leave it alone until morning. Many car brands offer apps that allow EV owners to set the charging start and end times.

This is helpful as it allows them to have the car charge during off-peak tariff hours. This is typically the least expensive time to tap into the electricity network, meaning even better savings. Most people are asleep and fewer appliances and electronics are running, allowing for more optimal and affordable use of power.

Can an EV Be Safely Plugged in Overnight?

Yes. As said, it is standard practice and with in-built battery management systems, there is no risk of overcharging. These systems will slow down the charging process when they detect that the battery is nearly full. Once the battery reaches 100%, the system switches to trickle charging. This is intermittent charging up of the battery once it is slightly drained by self-discharging.

EVs will continually use up some battery power to keep certain electric functions running even when parked. Trickle charging restores full battery charge periodically until your remove the type 1 or type 2 charging cable. It allows EV owners to find their cars full charged, but not overcharged, once they are ready to set off in the morning.

How Much Does It Cost?

If you consider a standard EV with a 60 kWh battery, it should cost about £8.40 to achieve a full charge overnight on domestic tariffs. This should provide a range of about 200 miles. Those with larger capacity batteries, such as Tesla models, will attract a higher cost to achieve a full charge. Overnight charging is the most cost-effective and practical way to keep your car charged up.

There are also some opportunities to enjoy free charging. Many shopping centres and parking areas have free charging stations you can use for the duration of your visit. There are some office and other commercial areas that also offer the same benefit to their employees and customers. The Tesla Supercharger Network has an array of charging points across the country that are free for Tesla owners to use.

There are also paid charging stations you can access in places like service stations. You can easily look up the options in your vicinity through apps. Some stations require just using the app to access, make payment and monitor charging levels. Others may require you to acquire an RFID card to access their charging points.

What About If I’ll Be Gone for A Prolonged Period?

Overnight charging is an easy routine to maintain when you typically leave home each day to drive to work. If, however, you are not going to use your car for days on end, should you still leave your car plugged in? The best option is to consult your car manual.

While leaving your car plugged in even for a few weeks may not have a bad effect, sustaining full charge for a long time may cause the battery to slightly degrade faster over time. This could negatively affect its lifespan, although not very adversely.

For the more cautious types, it may be best to fully charge the battery and then unplug. If its rate of discharge means the battery will not fall below 30% by the time you get back, it should be fine. 30% is considered the threshold to maintaining long-term performance of EV batteries.

What Is the Impact of a Prolonged Full Charge?

As said, overcharging is almost impossible thanks to the in-built battery management system. However, keeping your battery at full capacity for too long can have some slightly negative effect on its lifespan. If left plugged in for over 8 hours are 100% charge, the battery may begin to degrade slightly faster.

Battery degradation is to be expected even with the normal use of your EV, gradually reducing the range of the vehicle. On average, most EV vehicles lose about 2.3% per year. This figure should however not inspire fear as most batteries are expected to outlive the useable life of the cars themselves. The best course of action is to avoid plugging in for too long after a full charge is attained and avoid low charges of less than 30% for long periods as well.

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