Why is My Electric Car Not Charging at Full Speed?

Battery-powered Electric Vehicles (EVs) have become game-changing in the technology and automobile industry that people love instead of traditional gasoline engines. EVs are fully electric vehicles with rechargeable batteries, just like we charge and use our smartphones and smartwatches. As battery technology has improved in recent years, more people and car lovers are gradually switching to EVs. But have you ever noticed that your Electric Car is Not Charging at Full Speed? Well, you’re not alone.

Sometimes, you may feel that you’ve plugged in your Electric Vehicle to the charging, and it’s still only at 50% of charge instead of fast charging. In that case, you may get frustrated when your EV doesn’t charge at a faster speed. A slow charging speed can also damage the battery or the charger in worse scenarios. However, there are several other possibilities applicable behind the slower charging speed, which was previously charging faster to the electric vehicle.

Charging times for electric vehicles aren’t always the same as you expect due to the actual power output of a charging station or degradation of the battery health. It’s always better to find the best way to charge your electric vehicle (EV) by calculating the maximum speed of a charger or charging station from where used to charge your EV regularly. It’s important to remember the maximum charging output which is 7 kW, 11 kW, or 22 kW (kilowatt) can be offered by home charging stations.

Why is My Electric Car Not Charging at Full Speed?
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What are the Kilowatt Differences?

kW in charging indicates the actual rate of electrical current flow which states the maximum power output of a charging station and EV charging rate. In case, there is a difference between these two metrics then the charging speed may get restricted or vary depending on the electric car’s charging capacity or the charger speed. For instance, if an EV supports an 11 kW maximum charging rate and is connected to a 22 kW charger, it will charge at a maximum speed of 11 kW due to the capacity limit. So, your EV and charging station both require fast charging support.

The more kW charging rate your EV supports, the faster your EV will get charged with a higher kW charger, respectively. So, we can expect that your electric car will take 12 hours to fully charge with the 7.4 kW charger and 8 hours with the 11/22 kW charger in general conditions.

Why is My Electric Car Not Charging at Full Speed?

Well, as we’ve already mentioned above, your electric car may not charge faster like earlier due to some limitations or degraded hardware capabilities such as a faulty charger, degraded battery life, increased battery temperature, not enough power output, the energy level of your EV (state of charge), etc.

Whereas simultaneous battery charging in a day, software limitations, using your car while charging, using a lower-gauge wire for charger, charging your EV during peak hours, using extension cables for charging, and more can also lead to slow charging speeds.

Now, you know the possibility of slow charging issues with your electric vehicle, which you need to check properly. To optimize EV charging speeds, you can check the brief details of the reasons below.

1. Conflicts with the Maximum Charging Capacity and Power Output

You should cross-check the maximum battery charging capacity of your Electric Vehicle and the maximum power output provided by the charging station that you’re using. This is the first preference to check for the common reason behind your EV’s slow charging speed, which is what you expected. If your EV was charging faster in the past, that means there is some conflict between the charging capacity and power output level.

In short, either your electric car can’t handle the maximum charging load or the charging station doesn’t have the faster charging output. This sort of mismatch can often cause multiple issues with charging speeds.

2. Battery State of Charge (SoC)

The Battery State of Charge (SoC) indicates how much energy your electric car currently has. In short, SoC means the battery percentage of the EV. Capacity and a charging station’s power output aren’t the only factors influencing charging time, another important one is the state of charge (or SoC).

Gasoline-powered vehicles fill up instantly at the same rate as how much you’ll fill up the tank. However, the lithium-ion batteries used in EVs can’t be charged instantly at the same charging speed depending on the existing battery level. So, if your EV battery is low on charge, like 0-80 percent, then it will charge faster. But after charging the battery to 80%, the next charge from 80-100 percent will take some time comparatively.

This technology is considered a trickle charging method to reduce battery damage or overheating issues over time. We should mention that most EV manufacturers don’t recommend regularly charging their electric cars more than 80 percent unless you’re having an emergency or want to charge the battery full to drive a long way. But you should avoid charging your EV to full battery percentage daily to prevent battery ageing.

3. Charging Simultaneously

It’s also expected that you’re charging the EV simultaneously daily, which eventually affects the battery charging speed because not all charging stations allow simultaneous charging to the EVs. In case the charging station uses separate units with the same transformer, the maximum power output can be reduced by half when both units are in use. You should choose a public charging station with fewer vehicles connected to get maximum charging speeds at the time.

4. Battery Temperature

Battery temperature can also affect the charging speed of an electric vehicle, which is important to avoid battery health issues. EV batteries are designed and developed to charge properly at an optimal temperature of 20° Celsius approximately. Whenever the temperature increases significantly, the EV battery can be damaged over time and the charging capacity will also be reduced.

As per reports, EV batteries are designed with a Battery Management System (BMS) that monitors battery activities and manages overall charging capacity to prolong the battery health.

5. Using Your EV While Charging

Sometimes you may also think using your electric vehicle during battery charging won’t make any huge difference. But that’s not the case because using your EV or even sitting inside the electric car while charging may impact the overall battery charging speed. Though you won’t be able to drive your EV while charging, staying inside the car and using air conditioning or infotainment system or lights can increase the energy consumption, and the charging speed may get slow enough.

6. Charging Speed Varies Season-wise

Electric car battery charging can become slower depending on the season change, such as summer or winter weather. During extreme weather conditions, the EV charging can vary, which results in slower charging speed than in optimal weather. The battery charging speed decreases, and it takes maximum time to charge fully during the cold season. An electric car can lose up to 4 per cent of its battery level when parked overnight in cold weather.

Whereas the hot humid weather conditions can easily increase the battery temperature overall which leads to slow charging speed to avoid overheating issues.

7. Degraded Battery Health

Even though EV batteries can last longer, as per the company’s claim, for a lifespan of approximately 10-15 years, they typically last slightly less than expected. Depending on the battery usage, charging cycle, other features in the car, temperature, and more, EV batteries can charge slower due to degraded battery health. So, if your EV battery has been degraded, you may have issues with slower charging most of the time. In this case, you should replace the battery or get it checked by professionals.

8. Issues with the Charger or Charging Station

Not all charging stations or chargers have similar capacities. If your electric vehicle is charging faster at home but not fast charging at any charging station, then you’ll need to try going to another location to cross-check the different charging stations. Sometimes, compatibility issues with the charger or charging station might also trouble you with the slow charging speed. So, you’ll have to check if the charger or charging station offers a fast charging limit.

If multiple EVs are connected to a charging station simultaneously, the overall charging speed may be reduced drastically. So, either you can find another charging station or wait patiently for the existing charger to charge slowly.

9. EV Software Limitations or Conflicts

Most Electric Vehicle manufacturers periodically provide technology enhancements and software upgrades to give a better experience. So, you should check for pending software updates for your EV model and install the latest firmware updates. This will help reduce battery aging issues or maintain battery health. Upgrading to the latest software version will also improve battery charging overall.

10. Using a Basic Level Charger

Well, using a basic level charger for your EV can not deliver a fast charging feature even if your EV can do so. It’s better to switch from a level 1 charger to a level 2 or rapid charger for a faster charging experience. If you’re using charging stations for faster charging, then use Level 2 superfast chargers for faster charging output, which will add a higher range (kilometers) per hour.

11. Use a Heavier-Gauge Wire for an EV Charger

This is a common thing for EV owners to have slow charging experiences at times or in some specific charging stations. Slow charging may occur if the charging unit is physically broken or faulty. Such issues are prone to happen in fast charging stations where more people prefer to charge their EVs regularly.

Even if you’re using a home charging unit, make sure to check for potential faults and the lower-gauge wire for an EV charger. So, try installing a new circuit or use a heavier-gauge wire for an EV charger to get better charging.

12. Charge your EV During Off-Peak Hours

The chances are high that somehow you’re charging your electric car during peak hours in a day when more EVs are getting charged at the same time. Additionally, the peak hours in a full day can also demand more power sources. So, try charging your electric vehicle during off-peak hours to avoid potentially slower charging speed because there will be less pressure on the electrical grid.

13. Regularly Maintain Your EV and Charger

Last but not least, you should also go through the periodic maintenance of your electric vehicle and the charging equipment for an optimised charging experience. No matter whether your EV is under warranty or out of warranty, you should visit the nearest service centre of your car’s manufacturer to get it checked thoroughly. In case, there is some loophole or potential issue with the car as well as battery, you’ll know it after the inspection & scheduled maintenance.


The battery in your electric vehicle (EV) is one of the most important and expensive components. EV batteries are built for a long last on average usage and are quite fragile too. So, you should understand all the advantages and disadvantages of your EV battery to take care properly. You can also read the user manual of the specific EV model provided by the manufacturer to know more about the process of taking care of your battery as well as charging optimizations.

That’s it, guys. We assume this guide was helpful to you. For further queries, you can comment below.

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