Electric vehicle owners can unknowingly make mistakes during the charging process that can both shorten battery life and create safety risks. Below is our article on the most common mistakes and why each one is wrong.

Using the Wrong Charging Cable

There are cables on the market that are cheap, designed to different standards, or lack a certificate of conformity. These cables can lead to several negative situations:

  • The insulation material on low-quality conductors can deteriorate when heated, posing a fire hazard.
  • Data sent to the vehicle's battery management system (BMS) may be faulty, preventing the cells from charging evenly.
  • Cables that wear out quickly can eventually lead to intermittent charging or connection dropouts.

Recommended Practice:

When selecting an electric vehicle charging cable, it is crucial that it complies with the international charging standards specified by your vehicle's manufacturer (e.g., Type 2, CCS, or CHAdeMO). These standards ensure that your vehicle charges in the most efficient and safest way. Furthermore, it is essential to choose cables with safety and quality certifications such as CE, TÜV, or UL. These certifications guarantee the cable's safe use and high performance.

To ensure your cable has a long and safe operational life, it should be inspected regularly. If you notice signs such as cracks in the cable's sheath, breaks, or excessive heating, you must replace the cable immediately. Such simple yet important precautions not only enhance safety but also improve your vehicle's charging performance. Efficient charging for your electric vehicle is achieved through the right equipment and careful use.

 

Constantly Charging the Vehicle to 100%

Although filling the battery to 100% capacity every time may seem appealing, it leads to the following problems in the long run:

  • High-voltage stress: Prolonged exposure of the cell chemistry to high voltage causes microscopic degradation of the electrode material.
  • Storage losses: A fully charged battery can lose a few percentage points of its capacity in a short time, causing you to lose your initial range more quickly.

Recommended Practice:

Keeping electric vehicle batteries between 80% and 90% is the ideal charging range recommended by manufacturers. Charging to this level preserves the battery's chemical structure and extends its life. While it may be necessary to charge to 100% for long journeys, bringing the charge level back below 80% upon arrival helps maintain battery health. 

To make the charging process more efficient, you can use your vehicle's or charging unit's timer features to schedule charging, for instance, "charge to 80% by 2:00 AM." This allows you to save on energy costs and ensures the battery charges at an optimal temperature.


Leaving the Vehicle Plugged in for a Long Time

Leaving your vehicle connected to the charging cable for days or weeks, while giving users a sense of being "more prepared," can cause issues:

  • Cell heating even when the BMS is active: If the protection mode remains constantly active, the thermal equipment around the battery works overtime, and mechanical parts become fatigued.
  • Energy backflow (vampire drain): In some systems, the charging unit or the vehicle may draw a small amount of energy from the battery; a vehicle left plugged in for a long time consumes unnecessary electricity.

Recommended Practice:

It is important to take certain precautions for safety and energy efficiency during electric vehicle charging. For example, using a timer that automatically cuts off the energy flow once charging is complete prevents overcharging and saves energy. Additionally, by unplugging the cable during short-term parking, you can protect your vehicle's battery, especially in hot weather or after driving in heavy traffic.

Charging Every Day

How does daily charging, especially when it leads to excess cycles, affect battery life?

  • Every cycle causes wear: The number of battery cycles is the primary limiting factor for its lifespan; each full cycle (0-100% or even 20-80%) mechanically degrades the cell mechanism to some extent.
  • The importance of depth of discharge: Even if you perform continuous small cycles, if you do not maintain the 20-80% range, these cycles will also increase total wear in the long run.

Recommended Practice:

Developing goal-oriented charging habits is important for extending the battery life of electric vehicles and ensuring efficient use. For short-distance weekday use, keeping the battery between 50% and 70% preserves battery health and prevents unnecessary energy consumption. 

For long weekend travel plans, raising the battery level to 80%-90% reduces range anxiety and means you will need to charge less during your journey. Furthermore, periodically performing a full charge cycle and then bringing the battery back to lower levels helps balance the battery's chemical memory and reduces capacity loss. Such practices extend the battery's life and ensure your electric vehicle operates efficiently.

  

Charging at Home with an Inadequate Infrastructure

Common mistakes in home installations and their consequences:

  • Insufficient fuse protection: Circuits rated below 32A cannot handle a continuous 32A current, leading to an overload on the cable and panel.
  • Inadequate grounding: In an installation without a residual current device (RCD), an electrical leak poses a serious danger to both people and equipment.
  • Unprofessional installation: An incorrect mounting angle for a wall-box charger increases the risk of water ingress and corrosion.

Recommended Practice:

For an electric vehicle charging station to operate safely and efficiently, it must comply with specific installation standards and regulations. The IEC 61851 standard is an internationally recognized norm for electric vehicle charging systems, and compliance with this standard guarantees the station's safety and performance. Therefore, it is important to have the charging unit installed by a licensed electrician. Additionally, ensuring the grounding system is correctly installed and using an RCCB/RCD type residual current device with a fuse rated for at least 32A enhances electrical safety. Periodic checks should not be neglected; annual technical maintenance, connection resistance measurement, and a grounding test will ensure the system's long-term and safe operation.

By avoiding these common mistakes, you can optimize your electric vehicle charging process to be both safe and protective of your battery's lifespan. Proper charging habits not only contribute to your budget but also to environmentally friendly sustainability in the long run. Have a good and safe journey!