Why is my car charging so slowly? Good question!
The answer depends on whether your car is charging slowly at home or in public.
In any case, slow charging rarely signifies an issue with your vehicle. Most slow charging sessions are caused by the charger. In this article, we’ll look at the commonest scenarios where you might experience slow charging.
Here are the main points:
- At public chargers, slow charging can be due to cold temperatures affecting the battery/charger or shared load with another vehicle.
- Slow charging after 80% at public chargers is normal to protect the battery.
- At home, slow charging may be from the charger sharing household load or the battery being too cold.
- Software updates or power cuts can also temporarily cause slower charging.
- To increase charging speed, preheat the battery and make sure charger settings are optimal. Slow charging is rarely a vehicle issue.
Let’s jump in!
Electric car charging slowly at a public charger
If your electric car isn’t charging at the maximum speed at a public charger, it’s probably because the temperature of the battery or charging station isn’t optimal. Low temperatures slow down the rate of power transfer, restricting charging speeds.
Another possible reason is shared load if someone else is plugged into the same charger, a characteristic that affects some rapid chargers.
Electric car charging slowly after 80%
If your electric car is charging slowly after 80% at a public charging station, this is perfectly normal behaviour. It is charging slowly because the charger is restricting charging speeds, a safety mechanism designed to stop your battery from overheating.
Charging to 80% is recommended to preserve the lifespan of your battery and makes sense because the last 20% takes as long as the previous 70%.
Electric car charging slowly at home
If your electric car is charging slowly at home, there are two possible reasons. It could be because your smart charger is sharing the load with the rest of your house, or because your battery isn’t warm enough to accept the fastest charging speeds.
If it’s cold outside, try pre-heating your battery. If this isn’t the problem, check your charger app to see if the power is set to the max charging speed (32A).
Electric car charging slowly after update
If your electric car is charging slowly after a software update, this could signify a problem with the update. Try charging your car normally a few times, and if the problem persists, try reverting to the previous software version.
If you can’t revert to the previous version, contact your vehicle manufacturer for support. It is their duty to investigate such problems.
Electric car charging slowly after a power cut
If you have had a power cut and your electric car is now charging slowly, it is probably a temporary problem caused by the charger resetting itself. If the problem persists, there’s probably a circuit somewhere creating a power imbalance.
Check your charger app to make sure it is still connected to the internet and your settings are still in place. If they are, wait and see what happens for 24-hours. If you still have slow charging, speak to an electrician.
Why does EV charging slow down?
At 80%, public charging stations cut charging speeds to prevent the battery from overheating. Below 80%, you will see slower charging speeds than the maximum rate when it’s cold outside because low temperatures affect power transfer.
This is annoying, especially when you have 800V architecture that promises to get you to 80% in less than 25 minutes!
Updates and power cuts can also yield slower charging times, although the most common reason for slow charging at home is the charger being set to a slow charge speed (e.g., 16A and not 32A) and shared capacity, when the charger receives reduced power because your house is consuming more electricity than normal.
Why is my Tesla charging slow?
There are a few common reasons why your Tesla may charge slowly. At public chargers, cold weather can reduce charging speeds, as can sharing the charger with another vehicle. After the battery reaches 80% charge, the charging speed is reduced to protect the battery.
At home, the charger may be sharing electrical load with the rest of your house, resulting in slower charging. Try preheating your battery before charging, and make sure the charger settings are set to maximum amperage (32A). Software updates or power outages can also temporarily slow charging until the system resets.
Overall, slow charging is rarely due to an issue with the vehicle itself. To increase charging speed, preheat the battery, charge below 80%, and ensure optimal charger settings.
How can you increase charging speeds?
Battery temperature plays a critical role in charge speeds as this article explains. Pre-heating the battery – or arriving at a charger with an optimal battery temperature – is the best way to increase charging speeds. You can also park in a temperature-controlled car park/garage.
Looking for an EV charger but not sure where to start? Read our guide on how to choose an EV charger.