If you own an electric car or are considering switching to an electric-powered vehicle, at some point you’ve probably wondered about battery charging. Common questions that new electric car owners have are: should I charge my electric car every night, and what would happen if I did?
You might also be wondering about your battery’s capacity and if you should allow it to reach a 100% charge.
The short of it all is that it is not recommended, nor is it necessary in most situations, to charge your electric vehicle every night. In fact, if you choose to charge it every night, you risk reducing the lifespan of its lithium-ion battery, as charging the battery to its maximum state of charge (SOC) can create stress on the battery that will eventually reduce its life. This may result in the need for a potentially costly replacement sooner than otherwise needed.
To find out how often you need to charge your electric car, you should refer to the user manual. Each electric car’s charging instructions, battery capacity, and range of miles will vary. How often you use your electric vehicle, and your daily driving mileage, will also factor into how often you should charge your electric car as well.
Can I Leave My EV Plugged in Overnight?
It is perfectly safe to leave your electric vehicle plugged in overnight. Today’s electric cars are built with amazing battery technologies such as built-in management systems. These systems are there to help to reduce the risk of your car being overcharged, thus reducing the risk of damaging the battery.
As the battery nears a full charge, the battery management system will kick on and take control and will cause the charging process to slow down. If the battery reaches a full charge before you unplug it, then the system will detect that and switch to a sporadic charging method. During this process, your battery will be charged intermittently, allowing the charging process to begin only when the battery drains slightly on its own.
With that being said, it is still recommended to consult the user manual just to be on the safe side on whether you can leave it plugged in overnight or not.
Thankfully, research into nightly charging itself has not shown any correlation to battery degradation. Rather, most electric vehicle batteries do not lose performance strictly by being charged nightly, and the number of times that a battery can be recharged (cycle life) continues to grow as the technology develops and improves.
A full charge cycle equates to going from 0 to 100%, which also means that not every plug-in represents a full cycle, giving you even more time with your electric vehicle battery.
Should I Charge My EV to 100%?
While having a full charge may provide you with the optimal operating time, it is not recommended to charge your electric vehicle to 100% under most circumstances. Charging your electric car to 100%, also referred to as the maximum state of charge (SOC), can cause a shortened lifespan and cost you more money in the long run.
Instead, a single charge of 80% to 90% should suffice and provide you with plenty of power for most scenarios. As an example, Tesla recommends that their cars be charged to 90% in a single charge. Having an 80% to 90% charge will give you a decent operation time, and should quell any range anxiety you might be experiencing while also ensuring that your battery’s life expectancy lasts as long as it should.
Similarly, you should also avoid letting the battery drain to 0%, as it can have the same damaging effects on your car’s battery as letting it reach a 100% charge. In fact, a good rule of thumb is that you should never let your car’s battery life fall below the 20% mark.
Many electric vehicles allow you, as the owner, to set the maximum charge for the battery, to keep it from being charged to its full capacity. Even easier than the manually-set maximums, some electric vehicles also offer advanced battery management systems. These systems prevent charging and discharging to either extreme, leaving reserves at either end of the battery ranges.
This means that, while your system may show a full 100% charge, the battery isn’t actually charging to its full 100%, but rather to a pre-determined lesser percentage, as set by the manufacturer.
Is it Cheaper to Charge Overnight?
Yes, it is, in fact, cheaper to charge your car overnight in many situations, though it may depend on where you live. Although charging stations are becoming more popular across the world, charging your electric car at home and at night still has plenty of benefits over charging them at these stations.
For example, many utility companies offer their customers a reduced rate when they use electricity during nighttime hours when peak hours are over. So, depending on your utility company’s terms of service, as well as where you live and the time of year it is, you may be able to save some money when charging your electric vehicle at night.
In some areas, electric car owners can even save up to 50% by charging their cars at night instead of during the day.
The benefit of charging it overnight doesn’t just end there, though. Having your electric vehicle charged and ready to go in the morning to take you to your job, appointment, or just to run errands will save you the headache of having to charge it last minute.
So, to answer the question, “should I charge my electric car every night?”, the straightforward answer is no. Charging your car every night can damage the battery capacity and permanently ruin the overall battery life of your electric vehicle. It very rarely requires a nightly charging session and how often you should charge your car will depend on how often you drive it, your daily range of miles, and the user’s manual.