How Long Does a Portable EV Charger Take to Charge? A Complete 2025 Guide

Portable EV chargers are becoming indispensable for drivers who need flexible charging solutions at home, at work, and on the road. One of the most common questions is: how long does a portable charger take to charge an electric vehicle?

The short answer: it depends. Charging time varies by charger power, EV battery capacity, charging efficiency, and environmental conditions. In this guide, we’ll break down all the key factors, compare charging times at different power levels, and share practical tips to reduce downtime.

Key Factors That Impact Portable Charger Charging Time

Battery Capacity of the EV

A smaller EV battery, such as 40 kWh, charges much faster than a larger 80–100 kWh pack. The more energy stored, the longer it takes to recharge.

Charger Power Levels

Portable chargers usually support multiple output modes: 3.5 kW, 7 kW, 11 kW, and 22 kW. Higher power means fewer hours to reach the same charge level.

Current and Voltage

At 230V, current options can range from 6A up to 32A. Using a higher current (when your EV and grid allow it) significantly reduces charging time.

Vehicle Limits and Charging Protocols

Even if your charger supports 22 kW, your EV might only accept 11 kW. Charging will be capped by the vehicle’s onboard charger.

Environmental Conditions

High heat or freezing temperatures may trigger safety systems that reduce charging speed. Ventilation and stable temperature help ensure consistent charging.

Typical Portable EV Charger Charging Times

Here’s an overview of estimated charging times (20–80% charge on a 60 kWh EV, ~40 kWh energy added):

Note: Real-world times vary by EV capacity, grid limits, and efficiency (~85–90%).

The EV Charging Curve Explained

Charging doesn’t happen at a constant rate:

• Bulk Stage (0–70%): Maximum current, fastest charging.
• Tapering Stage (70–90%): Current decreases to protect the battery.
• Top-Off Stage (90–100%): Very slow charging, often 30–60 extra minutes.

This explains why reaching 80% feels quick, but the last 20% takes longer.

Fast Charging vs Lower Power Charging

• Low Power (3.5 kW): Works on household outlets but can take 10+ hours.
• Medium Power (7–11 kW): Balanced for daily charging, 4–6 hours for many EVs.
• High Power (22 kW): Ideal for short downtime, reducing charging to just 2–3 hours if both EV and grid support it.

How to Charge Faster with a Portable Charger

If you’re wondering how long does a portable charger take to charge, here are ways to minimize the wait:

• Use the highest supported power mode (11–22 kW).
• Ensure wiring and connectors are rated for the required current.
• Charge in a cool, ventilated environment to avoid thermal cutback.
• Avoid running other high-load appliances on the same circuit.
• Match the EV’s max acceptance rate with the charger’s output for best efficiency.

FAQs on Portable Charger Charging Time

Q1. How many hours does it take to charge at 7 kW?
Around 5–6 hours to go from 20% to 80% for a 60 kWh EV.

Q2. Why is 3.5 kW so slow?
Because the current is limited (~16A), it takes 10–12 hours to add ~40 kWh.

Q3. Can I use 22 kW if my EV supports only 11 kW?
No. Charging will automatically be limited to 11 kW.

Q4. Does temperature affect charging time?
Yes. Extreme heat or cold can cause protective systems to reduce current.

Q5. Does faster charging damage EV batteries?
Not directly. What matters is avoiding overheating, voltage drops, and unsafe conditions.

Q6. How do I estimate charging time for my EV?
Use the formula:
Charging Time (hrs) = Battery Energy to Add (kWh) ÷ Charger Power (kW) × (1 ÷ Efficiency)

Final Thoughts

So, how long does a portable charger take to charge an EV? Depending on charger power and vehicle capacity, it can range from 10–12 hours at 3.5 kW to as little as 2–3 hours at 22 kW.

By choosing the right power mode, using quality connectors, and charging under safe conditions, you can maximize efficiency and minimize downtime with your portable EV charger.