The introduction: “The expansion of electric vehicles has shifted thought in transit from being powered by gasoline to the green alternative.” Yet a question that seems to be common among both buyers and current EV owners is: “Do electric cars lose charge while parked?” It is a fair question because knowing your car’s battery behavior when not being used may help you in strategizing your car’s range and charging schedule.
The short answer: Electric cars do lose charge while parked; however, in most cases, the amount of charge lost is quite insignificant. This article aims to explore the case of battery drain that occurs when an EV is parked, how high the charge loss can go, and what you can do about putting a stop to needless battery drainage.
The Basics of EV Battery Drain
To understand why an EV loses charge while parked, it would be necessary to shed some light on how lithium-ion batteries used in electric vehicles function. Just like your smartphone or laptop, an EV depends on a rechargeable battery pack to store energy that helps power the electric motor and the systems of the vehicle. They are advanced batteries, but they are not perfect and tend to lose charge after a while, be it when the vehicle is being driven or sitting idle.
Battery drain while parked is often referred to as “phantom drain” or “vampire drain.” These terms designate a small but steady drain on battery power due to background systems operating even with the car is not being driven. It’s a natural occurrence for any electric vehicle, but the energy lost can vary according to several parameters.
How Much Charge Do Electric Cars Lose When Parked?
Small power loss in parked EVs is generally a marginal phenomenon. Though the figure varies, the average charge lost by most EVs daily when parked and left idle is 1%-2%. There can be different variables affecting these rates: model of the vehicle, environmental conditions, and what system features are still active while parked.
1. Vehicle-Specific Considerations
Charge loss varies between different EV models according to their energy management systems. Some EVs are designed by their manufacturers with consideration to conserving energy while parked, whereas others work harder in sustaining themselves with energy consumption. For instance, high-end EVs with more sophisticated onboard tech and infotainment systems might lose charge at a slightly higher rate compared to basic ones.
2. Environmental Conditions
Environmental factors have a heavy hand in battery drain rate. Temperature extremes can also affect heavier battery drain.
Hot Condition: During hot weather, the BMS may intervene to cool down a battery so that it does not overheat, thus draining power.
Cold Condition: On the flip side, any battery chemistry will slow down in cold weather, while the heating mechanism in the vehicle will strive to make the cabin or battery warm. This necessitates increased energy usage and hence depletes the battery power while parked.
In either case, the power-consuming battery thermal management system is activated to protect the battery when the vehicle is idle.
3. Background Systems Running
EVs feature a range of background systems that are consumed by power even when the car is not in use. These systems are:
Security and Alarm Systems: Just as you would have an alarm on any regular car, EVs normally come with an active security system installed that shields the vehicle from theft. The system sips the battery a little.
Onboard Computer and Communication Systems: In some vehicles, these onboard computer systems enable remote monitoring functions; they may download software updates over the air and connect with apps such as Tesla’s mobile app or the Nissan Leaf app. Such systems keep “talking” to the car’s onboard computer, thereby causing a slight drain in the battery.
Climate Control Systems: Some EVs are capable of remotely preconditioning the cabin temperature by drawing power to heat or cool the car before one uses it. If it is left on or set to operate on automatic, a slight drain can happen while the vehicle is parked.
Battery Management System (BMS): In a car, a BMS constantly watches the battery’s parameters, balancing charge between cells, I might add, making sure that the battery always stands to function at its best. Even though these are operated at low power, they still take away some energy.
The Battery State of Health
As the U goes on, his EV battery that could hold a charge may charge much faster while parked. The cause of this is that the internal resistance increases with the number of charge cycles the battery goes through. Higher internal resistance in a battery means an older battery will lose more energy when compared to a new one.
Can Battery Drain Be Reduced While Parked?
There are a number of things you can do to minimize battery discharge during parking. Following them will increase the time between charges and will ensure that you are not surprised with a low charge.
1. Park in the Controlled Environment
Where possible, park the EV within the garages or any shaded areas where the temperature can be controlled. Extremely hot or cold conditions cause faster battery drains. Having a vehicle parked in a climate-controlled area would be quite beneficial, especially for a hot climate where excessive heat tends to discharge the batteries rather quickly. On the cold side, when temperatures tend to drop way below freezing, the heated garage takes some of the work off the battery thermal management system.
2. Shut Off Some Features
Stop using all the unnecessary features sucking battery power. For instance:
Remote access: Disable remote features that allow your car to be accessed through apps or communication systems when not in use.
Preconditioning: Keep preconditioning off unless you specifically want to keep the car cabin temperature controlled.
Climate Control: Automatic climate control should be turned off, especially in winter and summer, because it will keep drawing power trying to keep the battery or the cabin at a certain temperature.
3. Activate Energy-Saving Modes
Many EVs have inbuilt energy-saving modes that will reduce background activities, lower any unnecessary power consumption, and attempt to correctly utilize the vehicle’s battery while it is not in use. For instance, Tesla has an “Energy Saving Mode” which prevents the vehicle from draining power unnecessarily while parked for long periods. Refer to your car’s handbook to know how to enable the energy-saving options.
4. Scheduled Charging and Charging Limits
The other way to mitigate battery wear in a parked car is to have charging schedules or restrict the SOC so the car does not sit at full charge for long. If you charge the battery to 100% and leave it there for a long time, battery degradation will occur. For a long stay, it is good to keep the charge between 20% and 80% for the best battery health.
Some electric cars may allow you to set the car to charge only at certain times, usually when electricity rates are low, which is another way to avoid draining the battery while parked.
How much charge can one expect to lose?
As we mentioned earlier, charging loss will usually vary from 1 to 2 per cent every 24 hours, depending on the factors discussed. However, there are some important caveats:
In mild weather, if your vehicle enters energy-saving mode, you may be able to lose just 1% of the battery charge per day.
If it is hot or cold, and there is a climate control system working, or maybe pre-conditioning as well, you could have a few more drains, around 2% or more.
With a 60-kWh battery losing 1% charge each day, you are losing 0.6 kWh of usable energy. Over a week, that amounts to about 4.2 kWh, which translates to a range reduction of 15 to 20 miles, depending on how efficiently your car uses energy.
What Happens to My EV if I Leave It Uncharged for a Long Time?
Leaving your EV parked for longer periods with batteries in a low state of charge can lead to degradation. Most EVs are designed so that you cannot drain them completely as a safety measure. Still, keeping them at a very low state of charge for long periods can cause permanent damage to the cells.
Therefore, it is advisable:
To at least charge 30% before leaving the car unused for an extended time.
Use storage modes that some manufacturers offer to preserve the battery’s health when the car is not being used.
Conclusion: Do Electric Cars Lose Charge When Parked?
Yes, there is indeed some loss of charge in electric cars when being parked, but the quantity of charge lost is usually very minimal, about 1% to 2% per day, approximately under normal conditions. This is a natural operation of lithium-ion batteries. Mainly, all drain-on-the-battery issues are being created by background systems of the car (i.e., security, communication, and battery management systems) and environmental factors (temperature).
This being a phenomenon cannot be stopped, but there are numerous ways one can lessen the drain on batteries while parked, such as parking in a controlled environment, using energy-saving modes, and turning off functions that are not needed. Keeping in mind these factors will keep the EV ready whenever needed, keeping battery drain at a minimum.