Ever plugged in your EV and returned later to find it's still only 50% charged? Us to. It can be frustrating when your EV is charging slower than it used to. You may also worry about damage to the battery or the charger. While that's a possibility, there are several other reasons why you're previously super-fast charging is getting slower.

Here are 6reasons why your EV isn’t charging as fast as before (and how to fix them).

Cause #1 - Battery degradation

Like the battery in your phone or laptop, your EV battery can degrade over time. This means that it's unable to cope with the high charge rate, which results in slower charging times. While this is fine if you're leaving your vehicle overnight, it can cause problems when you want a rapid roadside top-up.

Solution: EV battery degradation is normal. The more times that you charge your EV car battery, the less efficient it is. While there's no way to fix the issue (aside from replacing the battery), there are ways to maximize your EV battery lifespan. You should follow the recommended charging processes and avoid deep discharges (where you almost empty your battery of charge).

Cause #2 - State of charge

Your battery's state of charge (SOC) can determine how quickly it charges. When your battery is empty, your battery will charge the fastest. As it gets fuller and fuller, the charge rate slows down. For example, it can take as long to get from 0-50% as it can to get from 50-75% charge.

You may find your battery only charges to 80% and then stops (or creeps up very slowly). This is because it can take as long to charge from 80-100% as it does getting from 0-80%.

Solution: Lithium-ion batteries don’t like to be fully charged or fully discharged. Instead, they’re at their most efficient in the mid-range. If your battery isn't getting to 100%, don't worry. Instead, aim to keep your battery mid-range for optimum performance and longevity. Sometimes, it can't get to 100%, and that's just fine.

Cause #3  - Charging infrastructure issues

Not all charging stations are equal. If your EV is charging quickly at home but not at work, it could be because the station isn't as efficient. In some cases, the charging station's power output may be lower than your EV's maximum capacity, which can mean slower charging.

You may also find that charging speeds can drop when multiple vehicles are connected to a charging station.

Solution: Unfortunately, you can do little to improve charging station efficiency. You will simply have to find somewhere comfortable to sit and wait. If you are going to have to use a less-efficient charger, or one with multiple connections, plan ahead and give yourself some extra time to top-up

Cause #4  - High temperatures

We all love the sun, but sadly our EV batteries don’t! Extreme heat can have a massive impact on battery performance and limit its ability to accept a high charger ate. Why? It's all about safety. The intelligent charging system inside your EV constantly monitors its battery's health, stability, and safety. Rapidly recharging a warm battery could lead to overheating and an incredibly dangerous phenomenon known as thermal runaway, where the battery pack combusts.

Solution: You can't control the weather but can control where you park your car. Leaving it in a shady spot(under a tree or in a garage) can help lower battery temperatures. In sweltering temperatures, you may want to consider pre-cooling the battery before charging.

Cause #5  - Software limitations and upgrades

EVs are packed full of technology that is responsible for managing charging and maintaining the battery. Manufacturers regularly update their software to optimize how their vehicles operate, and you don't have a choice whether you want it or not.

Sometimes, EV builders will change the charging algorithms, affecting recharge speed. The updated software may prioritize battery health over charging speed, for example.

Solution: Stay up to date with all details on your EV software! While you don’t have any choice in the software your vehicle runs, they may provide information and advice along side details of updates that can help you to improve your vehicle’s charging performance.

Cause #6  - Faulty charging equipment

Yes, it can happen that you plug your EV into a charger that’s broken or faulty. Common causes of slow charging are damaged cables and connectors. It’s more likely to happen in high-use charging stations, such as those at offices or at service stations.

Solution: EV charging stations are complex pieces of machinery that deal with huge amounts of electrical power. If you notice a damaged charging station, safely unplug your car and inform someone. If a station is broken, the simple solution is to find another one (we hope you've got enough charge left to get there!).

Protecting your battery

The battery in your car is the most expensive component in your EV and one of the most fragile. After investing in an EV, you must learn how to care for your battery, optimizing its charging for maximum efficiency. Understanding the factors that can affect charging speed is essential for diagnosing the problem and finding a solution. In many cases, you'll simply have to wait a little longer for an EV charge, but we think it’s worth waiting for.

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